Isomerization of Light Naphtha Full and Final
Short Description
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Description
ISOMERIZATION OF LIGHT NAPHTHA
Group No. 1
Batch: 2008-2009
Names
Seat no.
MUHIB NASEER MANSURI
CH-005
WAHAJ SHAFI
CH-006
FARHAN AHMED LARIK
CH-058
KHURRAM REHMAN NIZAMI
CH-063
Internal Advisor: Sir Fahim Uddin
DEPARTMENT OF CHEMICAL ENGINEERING NED UNIVERSITY OF ENGINEERING AND TECHNOLOGY
Dedicated to Our beloved Parents & Teachers
CERTIFICATE This is to certify that the work in this project report on ISOMERIZATION OF LIGHT NAPHTHA is entirely written by the following students under the supervision of Mr. Fahim Uddin. This project is submitted to Department of Chemical Engineering for the fulfillment of the Bachelor Degree in Chemical Engineering.
Group No. 1
Batch: 2008-2009
Names
Seat no.
MUHIB NASEER MANSOORI
CH-005
WAHAJ SHAFI
CH-006
FARHAN AHMED LARIK
CH-058
KHURRAM REHMAN NIZAMI
CH-063
___________ Internal Adviser
___________
___________
Examiner – 1
Examiner – 2
DEPARTMENT OF CHEMICAL ENGINEERING NED UNIVERSITY OF ENGINEERING AND TECHNOLOGY i
ABSTRACT
Energy exploration and conservation is one of the most critical challenge faced by today‘s engineering world. Engineers of various expertises are working all over the world for developing new modes of power generation and energy conservation. This surge includes not only to find the new sources of energy but rather more significantly to enhance the efficiency of already existing resources by adopting more fruitful ways of power generation and reducing the amount of waste. Conversion of low energy fuels into high energy fuels is one of the key aspects in this regard. Petroleum refinery sector is also facing this widespread challenge. De-bottle necking of various refinery processes are being carried out. For refinery sector, bringing a maximum amount or refinery product into gasoline pool has been an attractive choice for years. This has been done by converting various straight run cuts of crude oil into the gasoline cut which is only about 7% of the feed crude. Several processes including alkylation, reforming, cracking and isomerization are carried out to enhance the production of gasoline pool. In Pakistan, the refinery sector is in practice of exporting Light straight run naphtha (LSR) which is one of the key products, where it is either used in petrochemical industries or it processed to increase its octane rating thus making it fit to be used as an automobile fuel. Isomerization of light straight run naphtha has now been done worldwide to increase its octane rating. The octane rating of LSR can be enhanced by converting the straight chain paraffins into branched chains. However the benzene present in LSR is hazardous for the environment due to its carcinogenicity. This problem can be solved by saturating this benzene into cyclo-hexane. Consequently a combination of two processes that is saturation of benzene into cyclo-hexane followed by isomerization of normal paraffin into iso paraffin under the action of Platinum based on alumina catalyst is developed. This report will discuss in detail this process for the LSR produced from Atmospheric distillation column at Pakistan Refinery Limited. This report will discuss process history, chemistry of the process, material and energy balances, equipment design, economics for the process and environmental and safety concerns.
ii
ACKNOWLEDGEMENT
Our first thanks is to Allah The Almighty, the most merciful who blessed us with the strength to achieve our task and helped us in all ups and downs during the final year project in particular and in circles of life in general. This final year project will hopefully serve us as a milestone in signifying the essence of Chemical Engineering design. This project was rather an expedition characterized by the team work, as well as by help from various personnel. Henceforth we are in debt to acknowledge their support and guidance in completion of our project. First and foremost we would like to acknowledge our project facilitator Engineer Fahim Uddin who supported us and always drew a helping hand when needed. Most importantly encouraged us to attempt this project unconventionally and provide us full autonomy to enhance our talent and abilities. Secondly, we would like to express our gratitude and acknowledgement to the support of Engineer Tariq Masood (Senior Engineer Pakistan Refinery Limited) and Engineer Rashid Hafeez (Process Manager Pakistan Refinery Limited) Apart from the above mentioned, we would also like to acknowledge the grand support of Professor Dr. Tufail Ahmed (Dean Chemical and Process Engineering), Professor Dr. Inayatullah Memon (Chairman DEC) and all the faculty members of department of Chemical Engineering especially Prof. Dr. Shazia F. Ali, Mr. Asim Mushtaq, Mr. Adeel-ur-Rehman and our class advisor Mr. Saad Nadeem for his time by time encouragement.
Authors
iii
CONTENTS ABSTRACT
ii
ACKNOWLEDGEMENT
iii
CONTENTS
iv
LIST OF FIGURES
viii
NOTATIONS
x
CHAPTER
1
INTRODUCTION
01-12
1.1
Refinery Products
02
1.2
Automobile Fuels
06
1.3
Octane number
06
1.4
Processing of heavier and lighter hydrocarbons than C7 and C8
07
1.5
What is Isomerization?
10
CHAPTER
2
ISOMERIZATION TECHNIQUES
13-22
2.1
UOP‘S Penex Process
13
2.2
Process Description
19
2.3
Octane Comparison for Different Processes
22
CHAPTER
3
PROCESS DESCRIPTION
23-42
3.1
Simple Process Description
23
3.2
Process Chemistry
24
3.3
Reactions
26
3.4
Process Variables
30 iv
3.5
Process Equipment
CHAPTER
35
4
CATALYST SELECTION
43-49
4.1
Catalyst
43
4.2
Types of Catalysts
43
4.3
Dual-Functional Isomerization Catalysts
45
4.4
Alumina Catalyst
46
4.5
Chlorinated-Alumina based Catalysts
48
4.6
Zeolites
48
4.7
Zeolite Characteristics
49
CHAPTER
5
MATERIAL BALANCE
50-65
5.1
Material Balance Equations
50
5.2
Mass Balance on Mixer M 101
53
5.3
Material Balance around Reactors R 101 & R 102
55
5.4
Material Balance around Stabilizer T 101
61
5.5
Material Balance around Scrubber T 102
64
CHAPTER
6
ENERGY BALANCE
66-93
6.1
Energy Balance Equations
66
6.2
Energy Balance Around Reactor R-101
66
6.3
Energy Balance Around Reactor R-102
72
6.4
Energy Balance Around Heat Exchanger E 101
78
6.5
Energy Balance Around Heat Exchanger E 102
85
v
6.6
Energy Balance Around Stabilizer T 101
CHAPTER
92
7
PLANT DESIGN CALCULATIONS
94-118
7.1
Reactors And its Types
94
7.2
Algorithm for determining reaction mechanism and rate-limiting step
95
7.3
Designing of Reactor R 101
97
7.4
Designing of Reactor R 102
99
7.5
Designing of Naphtha Feed Pump P 101
101
7.7
Designing of Heat Exchanger E 101
104
7.8
Designing of Stabilizer T-101
107
7.6
Designing of Hydrogen Feed Compressor K 101
113
CHAPTER
8
COST ESTIMATION
119-128
8.1
Cost Estimation
120
8.2
Cost Estimation of our plant
123
8.3
Economics of Plant Location
125
8.4
Plant Location and Site Selection
126
CHAPTER
9
ENVIRONMENT AND SAFETY
129-142
9.1
Definition of a Petroleum Refinery
129
9.2
Background
129
9.3
Processes involved in refining crude oil
130
vi
9.4
Environmental hazards of petroleum refineries
134
9.5
Material Safety Data Sheet
134
CHAPTER
10
INSTRUMENTATION AND CONTROL
143-151
10.1
Components of the Control System
144
10.2
Analysis of Measurement
144
10.3
Controller
145
10.4
Characteristics of Controller
145
10.5
Modes of Control
146
10.6
Alarms and Safety Trips
146
10.7
Control loops
146
10.8
Feed Back Control Loop
147
10.9
Feed Forward Control Loop
147
10.10 Ratio Control
147
10.11 Auctioneering Control Loop
148
10.12 Split Range Loop
148
10.13 Cascade Control Loop
148
10.14 Interlocks
148
10.15 Control of Heat Exchanger
148
REFERENCES
152
LIST OF APPENDICES
154
vii
LIST OF FIGURES Number Figure
Title
Page Number
Figure 1.1
Crude Distillation Products
2
Figure 1.2
The isomerization reactions kinetics
11
Figure 1.3
Comparison of operating Conditions of Catalyst
12
Figure 2.1
Hydrocarbon Once-Through Penex Process
15
Figure 2.2
Block flow diagram of ―one through‖ process
17
Figure 2.3
Block flow diagram of process with DIP
18
Figure 2.4
DIP-Penex-DIH
19
Figure 2.5
Penex/Molex Process flow scheme
19
Figure 2.6
BFD of Molex Process
20
Figure 2.7
Octane Comparison for different Processes {Feed RON = 60 to 70}
22
Figure 3.1
C5 paraffin equilibrium plot
26
Figure 3.2
Equilibrium composition of hexane isomers in relation to temperature
26
Figure 3.3
Iso-pentane equilibrium curve
32
Figure 3.4
2-2Dimethyl butane Equilibrium curve
33
Figure 3.5
Equilibrium Curve
33
Figure 3.6
Process Flow Diagram
42
Figure 4.1
Dependence of n-paraffins conversion on reaction temperature viii
43
Figure 4.2
Aluminum Oxide
47
Figure 4.3
Characteristics of chlorinated alumina Catalysts
Figure 4.4
48
Structure and dimension of different types of zeolite
49
Figure 4.5
Catalysts Performance Curves
49
Figure 5.1
Thermodynamic equilibrium for the isomerization of heptane
Figure 5.2
51
Thermodynamic equilibrium for the isomerization of Butane, pentane and hexane
ix
52
NOTATIONS
Rd
Fouling Factor
μ
Viscosity
Cp
Specific Heat
Q
Heat Duty
Ux
Overall Heat Transfer Coefficient
Ax
Surface area for heat transfer
Fa
Factor Area
Nt
Number of tubes
At
Area of tubes
Gt
Mass velocity
ht
Film coefficient
Wa
Mass flow rate of air
ha
Film coefficient
da
Density of air
Nmin
Minimum no. of stages
S
Separation Factor
Rmin
Minimum reflux ratio
CFS
Vapor flow rate
GPM
Liquid flow rate
σ
Surface Tension
ρv
Vapor density
ρl
Liquid density
α
Relative Volatility
R
Reflux ratio
S
Tray spacing
hct
Clear liquid height
Dh
Hole diameter
x
UN
Superficial vapor velocity based on net area
AN
Net area
SF
Derating factor
Ad
Down comer top area
At
Total tower cross section area
Dt
Tower diameter
Af
Fractional hole area
hw
Outlet weir height
hcl
Clearance under the down comer
T
Tray deck thickness
Lw
Outlet weir length
Ql
Liquid load
Adt
Down comer top area
Adb
Down comer bottom area
Ac
Active area
hd
Dry plate pressure drop
Cd
Orifice coefficient
Uh
Velocity through holes
Ah
Hole area
Aa
Active area
Hr
Residual head
how
Liquid head over the outlet weir
tr
Down comer residence time
Φ
Viscosity gradient correction
K
Thermal Conductivity
B
Correction Factor
Y
Correction Factor
F
Correction Factor
Fp
Air pressure drop factor
DR
Density ratio
N
Number of rows of tube in direction of flow
ACFM
Actual cubic feet per minute xi
NR
Modified Reynolds number
AR
Area ratio of fin tube
S
Specific gravity
de
Equivalent diameter (inch)
De
Equivalent diameter (ft)
H2
Hydrogen Gas
C1
Methane
C2
Ethane
C3
Propane
n C4
Normal Butane
n C5
Normal Pentane
n C6
Normal Hexane
n C7
Normal Heptane
i C4
Iso Butane
i C5
Iso Pentane
2 MP
2 Methyl Pentane
3 MP
3 Methyl Pentane
2, 2 DMB
2, 2 Di Methyl Butane
2,3DMB
2, 3 Di Methyl Butane
2 MH
2 Methyl Hexane
3 MH
3 Methyl Hexane
2, 2 DMP
2, 2 Di Methyl Pentane
2, 3 DMP
2, 3 Di Methyl Pentane
2, 4 DMP
2, 4 Di Methyl Pentane
3, 3 DMP
3, 3 Di Methyl Pentane
3 EP
3 Ethyl Pentane xii
C6H6
Benzene
C7H8
Toluene
CP
Cyclo Pentane
MCP
Methyl Cyclo Pentane
CH
Cyclo Hexane
ECP
Ethyl Cyclo Pentane
MCH
Methyl Cyclo Hexane
2, 2, 3 TMB
2, 2, 3 Tri Methyl Butane
H2O
Water
C2Cl4
Perchloro Ethylene
HCL
Hydrochloric Acid
xiii
CHAPTER 1
INTRODUCTION
Chapter 1
Introduction
CHAPTER # 1 INTRODUCTION
The world of today puts great emphasis on the use of the available sources of energy in the most economical way to meet the forthcoming challenges in the field of global energy consumption. This has enhanced the need of not only developing methods of efficient ways of utilizing a fuel but much more than that on developing fuels that are more equipment friendly and environment friendly. Energy sectors are working not only to find alternatives of conventional fossil fuels by replacing them with solar, wind and geothermal energy sources but at the same time already existing fuels are being made more efficient by treating them with various chemical and physical processes.
In the field of automotive the fuel consumption is increasing day by day with the decreasing prices of automotive for last few decades. This has forced the refinery sector to acquire possible ways which may increase the percentage of the crude distillate that can be used as gasoline. The gasoline cut that is obtained from the crude oil contains hydrocarbons of C7 and C8 range. This range of hydrocarbons has better compatibility with the operating conditions (temperature and pressure) of gasoline engine and thus required rate of combustion is obtained in the gasoline engine using them as fuels. This property of the fuel is distinguished by a quantity remarked as octane number. Hence in gasoline engines a major criterion for selection of fuels is its octane number.
For the reason mentioned above the crude refining sector turned its attention towards the effective ways of increasing the octane number of fractions of crude distillate (not C7and C8) by adopting different methods. The addition of small amount of TEL (tetra ethyl lead) in the gasoline pool has a remarkable increase in the pool octane number; this method was relatively very cheap and had been used for several years. However the carcinogenity of the lead urged the environmental safety organizations to put a ban on the use of TEL in the commercial gasoline. Ultimately a surge of finding the alternative methods of increasing the octane number of the gasoline pool 1
Chapter 1
Introduction
raised in the refining sectors, methods such as Alkylation and Isomerization were adopted for enhancing the octane ratings of the lighter ends of the crude distillate and method of Cracking was adopted to convert heavier ends (above C8) distillate into fractions of gasoline range. These different methods are being used in the refineries throughout the world. 1.1 REFINERY PRODUCTS: We shall firstly be discussing the types of the products that are obtained from a refinery (general fractions of crude distillate) and their classification. Raw crude oil obtained from the earth crust is pretreated to remove water and salt contents, then it is distilled at atmospheric pressure to obtain a series of products having a specific boiling range from 32 to 4300C.The residue from the atmospheric distillation column is further fractionated in a vacuum distillation column. A list of these products is given below:
Figure 1.1 Crude Distillation Products (Gary and Handwerk, 2001) Light straight run naphtha and heavy straight run naphtha constitute about 3% to 4% of the input crude. The range for naphtha is from C5 to C12. Light naphtha are the hydrocarbon fractions of range C5 to C6 (including normal, iso and cyclo pentanes and hexanes, olefins of C5 and C6 and benzene and its derivatives) whereas heavy naphtha ranges from C7 to C10 (including gasoline, jet fuels and aviation fuels). Crude oil is a complex liquid mixture made up of a vast number of hydrocarbon compounds that consist mainly of carbon and hydrogen in differing proportions. In addition, small amounts of organic compounds containing sulphur, oxygen, nitrogen and metals such as vanadium, nickel, iron and copper are also present. Hydrogen to 2
Chapter 1
Introduction
carbon ratios affects the physical properties of crude oil. As the hydrogen to carbon ratio decreases, the gravity and boiling point of the hydrocarbon compounds increases. Moreover, the higher the hydrogen to carbon ratio of the feedstock, the higher its value is to a refinery because less hydrogen is required. The composition of crude oil, on an elemental basis, falls within certain ranges regardless of its origin.
We shall be further discussing the types of the hydrocarbons that are obtained from the refining of crude oil. These different hydrocarbons are then classified according to their octane ratings. All types of crude oil give the following 4 major types of hydrocarbons.
Paraffin
Olefins
Naphthenes
Aromatics
1.1.1
Paraffins:
These are the hydrocarbons that have single bond between all carbons present in the chain. They have a general formula of CnH2n+2. The range of carbons in this type is from a single carbon to hundreds of carbon atoms.
These paraffins are further of two types:
a) Normal (n) paraffins b) Iso paraffins
Normal paraffins (n-paraffins or n-alkanes) are unbranched straight-Chain molecules. Each member of these paraffins differs from the next higher and the next lower member by a –CH2– group called a methylene group. They have similar chemical and physical properties, which change gradually as carbon atoms are added to the chain. Iso paraffins (or iso alkanes) are branched-type hydrocarbons that exhibit Structural isomerization. 3
Chapter 1
1.1.2
Introduction
Olefins:
These are the hydrocarbons that have either double or triple (at least one or more) or both types of bondings between the carbon atoms. They have a general formula of CnH2n. Olefins, also known as alkenes, are unsaturated hydrocarbons containing carbon– carbon double bonds. Compounds containing carbon–carbon triple bonds are known as acetylenes, and are also known as biolefins or alkynes.
Olefins are not naturally present in crude oils but they are formed during the conversion processes. They are more reactive than paraffins. The lightest alkenes are ethylene (C2H4) and propylene (C3H6), which is important feedstock for the petrochemical industry. The lightest alkyne is acetylene.
1.1.3
Naphthenes:
Hydrocarbons lying in this range have a cyclic or ring structure but with the limitation that all the bonds among neighboring carbons are single, they have a general formula of CnH2n. The boiling point and densities of naphthenes are higher than those of alkanes having the same number of carbon atoms. Naphthenes commonly present in crude oil are rings with five or six carbon atoms. These rings usually have alkyl substituents attached to them. Multi-ring naphthenes are Present in the heavier parts of the crude 4
Chapter 1
Introduction
oil. Examples of naphthenes are shown below
1.1.4
Aromatics:
These hydrocarbons have a cyclic structure along with alternative double bonds between the carbons joined in the ring. Benzene is a six carbon containing compound with alternative double and single bonds, benzene and its alternatives collectively constitute this group of hydrocarbons.
Crude oils from various origins contain different types of aromatic compounds in different concentrations. Light petroleum fractions contain mono-aromatics, which have one benzene ring with one or more of the hydrogen atoms substituted by another atom or alkyl groups. Examples of these compounds are toluene and xylene. Together with benzene, such compounds are important petrochemical feedstock, and their presence in gasoline increases the octane number.
5
Chapter 1
Introduction
1.2 AUTOMOBILE FUELS: The wide range of the refinery products obtained are sorted to be used as the fuel for different sectors. The cut of the refinery products used by the automobile sector is heptane and octane. This selection is governed by the combustion properties and the conditions provided by these engines to the fuel. One of the significant properties is the octane number of the fuel. 1.3 OCTANE NUMBER: An octane number is a measure of the knocking tendency of gasoline fuels in spark ignition engines. The ability of a fuel to resist auto-ignition during compression and prior to the spark ignition gives it a high octane number.
The octane number of a fuel is determined by measuring its knocking value compared to the knocking of a mixture of n-heptane and isooctane (2, 2, 4-rimethyl pentane). Pure n-heptane is assigned a value of zero octane while isooctane is assigned 100 octane. Hence, an 80 vol% isooctane mixture has an octane number of 80. Two octane tests can be performed for gasoline.
The motor octane number (MON) indicates engine performance at highway conditions with high speeds (900 rpm).
On the other hand, the research octane number (RON) is indicative of low-speed city driving (600 rpm).
The posted octane number (PON) is the arithmetic average of MON and RON. One of the standard tests is ASTM D2700.
6
Chapter 1
Introduction
1.4 PROCESSING OF HEAVIER AND LIGHTER HYDROCARBONS THAN C 7 AND C8: The range commonly used in gasoline pool is the C7 and C8 hydrocarbons. However some lighter ends and some heavier ends are converted into this range by processing to accommodate the increasing demand of the automobile fuel. Some of the common procedures are briefly discussed.
1.4.1
Alkylation:
The addition of an alkyl group to any compound is an alkylation reaction but in petroleum refining terminology the term alkylation is used for the reaction of low molecular weight olefins with an isoparaffins to form higher molecular weight isoparaffins. Although this reaction is simply the reverse of cracking, the belief that paraffin hydrocarbons are chemically inert delayed its discovery until about 1935. The need for high-octane aviation fuels during World War II acted as a stimulus to the development of the alkylation process for production of isoparaffinic gasoline of high octane number. The need for high-octane aviation fuels during World War II acted as a stimulus to the development of the alkylation process for production of isoparaffinic gasoline of high octane number.
The reactions occurring in both processes are complex and the product has a rather wide boiling range. By proper choice of operating conditions, most of the product can be made to fall within the gasoline boiling range with motor octane numbers from 88 to 94 and research octane numbers from 94 to 99. Alkylation processes using hydrofluoric or sulfuric acids as catalysts, only iso paraffins with tertiary carbon atoms, such as isobutane or isopentane, react with the olefins. In practice only isobutane is used because isopentane has a sufficiently high octane number and low vapor pressure to allow it to be effectively blended directly into finished gasoline. The principal reactions which occur in alkylation are the combinations of olefins with isoparaffins as follows:
7
Chapter 1
Introduction
The product streams leaving an alkylation unit are:
LPG grade propane liquid
Normal butane liquid
C5+ alkylate
Tar
1.4.2
Catalytic Reforming:
Catalytic reforming of heavy naphtha and isomerization of light naphtha constitute a very important source of products having high octane numbers which are key components in the production of gasoline, Environmental regulations limit on the benzene content in gasoline. If benzene is present in the final gasoline it produces carcinogenic material on combustion. Elimination of benzene forming hydrocarbons, such as hexane will prevent the formation of benzene, and this can be achieved by increasing the initial point of heavy naphtha. These light paraffinic hydrocarbons can be used in an isomerization unit to produce high octane number isomers. Catalytic reforming is the process of transforming C7–C10 hydrocarbons with low octane numbers to aromatics and iso-paraffins which have high octane numbers. It is a highly endothermic process requiring large amounts the straight run naphtha from the crude distillation unit is hydrotreated to remove sulphur, nitrogen and oxygen which can all deactivate the reforming catalyst. The hydrotreated naphtha (HTN) is fractionated into light naphtha (LN), which Is mainly C5–C6, and heavy naphtha (HN) which is mainly 8
Chapter 1
Introduction
C7–C10 hydrocarbons. It is important to remove C6 from the reformer feed because it will form benzene which is considered carcinogenic up on combustion. Light naphtha (LN) is isomerized in the isomerization unit.
Light naphtha can be cracked if introduced to the reformer. Hydrogen, produced in the reformer can be recycled to the naphtha hydrotreater, and the rest is sent to other units demanding hydrogen.
In catalytic reforming the structure of the straight run cuts are altered by using several techniques to make them lie within the gasoline range. Reforming Reactions
Paraffin Dehydrogenation
Naphthene Dehydrogenation of Cyclohexanes
Isomerization Isomerization is a mildly exothermic reaction and leads to the increase of an octane number.
Dehydrocyclization
9
Chapter 1
Introduction
Hydrocracking Reactions
1.5 WHAT IS ISOMERIZATION: Isomerization is the process in which light straight paraffins of low RON are transformed into branched chain using proper catalysts. The paraffins used are C4, C5 and C6. The number of the carbon atoms remains constant but the octane number increases. The naphtha obtained from the fractionation column of crude oil is hydrotreated and further fractionated into heavier and light naphtha. Heavier naphtha is (90-1900C) is used as a feed to the reforming unit. The light naphtha obtained (max 800C) is used as a feed for the isomerization unit. The reforming unit cannot treat lighter naphtha because the C6 component of the paraffins tends to form benzene in the reforming unit; this is an undesirable event as benzene concentrations in the gasoline pool must be maintained down to a level because of its carcinogenity. 1.5.1
Thermodynamics of reaction:
The isomerization reactions are slightly exothermic and the reactions are carried out at equilibrium (reversible reaction of significant level) the reaction equilibrium is unaffected by the pressure variation as the number of moles on both sides remain same. However kinetic studies have shown that a temperature of 125-1300C is optimum for the reaction to be carried out.
10
Chapter 1
Introduction
Figure 1.2
1.5.2
Isomerization Reactions:
Isomerization is a reversible and slightly exothermic reaction:
The conversion to iso-paraffin is not complete since the reaction is equilibrium conversion limited. It does not depend on pressure, but it can be increased by lowering the temperature. However operating at low temperatures will decrease the reaction rate. For this reason a very active catalyst must be used. 1.5.3
Isomerization Catalysts:
There are two types of isomerization catalysts
The standard Pt/chlorinated alumina
The Pt/zeolite catalyst.
Standard Isomerization Catalyst (Pt/chlorinated alumina) This bi-functional nature catalyst consists of highly chlorinated alumina (8–15w% chlorine) responsible for the acidic function of the catalyst. Platinum is deposited (0.3–0.5 wt%) on the alumina matrix. Platinum in the presence of hydrogen will prevent coke deposition, thus ensuring high catalyst activity. The reaction is performed at low temperature at about 1300C. To improve the equilibrium yield and to lower chlorine elution. The standard isomerization catalyst is sensitive to impurities such as water and sulphur traces which 11
Chapter 1
Introduction
will poison the catalyst and lower its activity. For this reason, the feed must be hydrotreated before isomerization. Furthermore, carbon tetrachloride must be injected in to the feed to activate the catalyst. The pressure of the hydrogen in the reactor will result in the elution of chlorine from the catalyst as hydrogenchloride. For all these reasons, the zeolite catalyst, which is resistant to impurities, was developed. 1.5.4
Zeolite Catalyst:
Zeolites are crystallized silico-aluminates that are used to give an acidic function to the catalyst. Metallic particles of platinum are impregnated on the surface of zeolites and act as hydrogen transfer centres. The zeolite catalyst can resist impurities and does not require feed pretreatment, but it does have lower activity and thus the reaction must be performed at a higher temperature of 250 0C. A comparison of the operating conditions for the alumina and zeolite processes is shown
Figure 1.3 Comparison of operating Conditions of Catalyst
12
CHAPTER 2
ISOMERIZATION TECHNIQUES
Chapter 2
Isomerization Techniques
CHAPTER # 2 INTRODUCTION UOP‘S PENEX PROCESS:
2.1
The Penex process has served as the primary isomerization technology for upgrading C5/C6 light straight-run naphtha feeds since UOP introduced it in 1958. This process has a wide range of operating configurations for optimum design flexibility and feedstock processing capabilities. The Penex process is a fixed-bed procedure that uses high activity chloride-promoted catalysts to isomerize C5/C6 paraffins to higher octane branched components. The reaction is conducted in the presence of a minor amount of hydrogen. Even though the chloride is converted to hydrogen chloride, carbon steel construction is used successfully because of the dry environment. For typical C5/C6 feeds, equilibrium will limit the product to 83 to 86 RON (Research Octane Number) on a single hydrocarbon pass basis. The operating conditions are such that promote isomerization and minimize hydrocracking. Operating conditions are not severe, as reflected by moderate operating pressure, low temperature, and low hydrogen partial pressure requirements. Ideally, this isomerization catalyst would convert all the feed paraffins to the high octane-number branched structures: normal pentane (nC5) to isopentane (iC5) and normal hexane (nC6) to 2,2- and 2,3-dimethylbutane. The reaction is controlled by a thermodynamic equilibrium that is more favorable at low temperature. Equipments Used in Penex Process:
Methanator feed effluent exchanger
Methanator feed steam exchanger
Methanator
Methanator knockout drum
Make-up gas dryers (2 in number)
Liquid feed dryer (2 in number)
Regenerant super heater 13
Chapter 2
Isomerization Techniques
Regenerant evaporator
Liquid feed surge drum
Charge pump (2 in number)
Chloride drum
Chloride injection pump (2 in number)
Combine feed exchanger (3 in number)
Reactors (2 in number)
Stabilizer column
Stabilizer re-boiler
Stabilizer overhead air cooler
Stabilizer overhead trim cooler
Stabilizer overhead separator
Stabilizer reflux pump (2 in number)
Net gas scrubber
Caustic circulation pump (2 in number)
Caustic tank
Water circulation pump (2 in number)
Water Tank
Water injection pump (2 in number)
Operation and Operating Conditions of some Penex Process Equipment: 2.1.1
Liquid Feed Driers Operation:
Hydro treated SR light naphtha at temperature 45 0C & pressure 4.5 kg/cm2 is passed through driers to control moisture at 1.0 ppmw in the feed. Drying medium is the molecular sieves. There are two drier, one remain in operation while the other is on regeneration. Isomerate is used as regenerant. Dry liquid feed is collected in feed surge drum. Molecular sieves are regenerated by isomerate & there replacement depends on the efficiency or after period of four year. 2.1.2
Make Up Gas Driers Operation:
Make up gas is dry by passing into dryers. Molecular sieves used as drying agents. Dry gas is control at moisture < 1.0 ppmv. Before drying of gas CO & CO2 is 14
Chapter 2
Isomerization Techniques
removed from the makeup gas. It is accomplished by passing the gas through Methanator. CO & CO2 are converted into methane in presence of Nickel oxide catalyst. Nickel catalyst cannot be regenerated. It is replaced totally; its life is 4-5 years. Temperature & pressure of Methanator is maintained 220 °C & 27 kg/cm2. 2.1.3
Reactor Operations:
Combine liquid feed & make up gas is heated in pre-heat exchangers & chloride is injected before entering the reactors. The Reactor System is typically designed to operate at a minimum pressure of 31.6 Kg/cm2 (g). Lead reactor inlet temperatures range from 131°C to 200°C and lag reactor inlet temperatures range from 142°C to 186°C. H2/HCBN mole ratio is maintained as 0.20 at reactors inlet & 0.05 at reactors outlet. 2.1.4
Stabilizer Operation:
Reactor effluents passed through stabilizer where lighter gases & propane is separated from the isomerate. Stabilizer column is operated at temperature 145 °C & pressure 18.0 kg/cm2. 2.1.5
Stabilizer Net Gas Scrubber Operation:
The purpose of net gas scrubbers is that to neutralize the net gas prior sending to fuel gas header with caustic (strength is 10%wt). Operating parameters of net scrubbers is that pressure is 6.5 kg/cm2 and temperature is 45 °C. The most common Penex process is Hydrocarbon Once-Through Penex process. 2.1.6
Hydrocarbon Once-Through Penex Process:
Figure 2.1 15
Chapter 2
Isomerization Techniques
2.1.6.1 Process Description: Hydrogen Once-Through Penex process flow scheme results in a substantial saving in capital equipment and utility costs by eliminating product separator and recycle gas compressor.
Light naphtha feed is charged to one of the two dryer vessels. These vessels are filled with molecular sieves, which remove water and protect the catalyst. After mixing with makeup hydrogen, the feed is heat-exchanged against reactor effluent. It then enters a charge heater before entering the reactors.
Typically, two reactors in series are used to achieve high on-stream efficiency. The catalyst can be replaced in one reactor while operation continues in the other. One characteristic of the process is that catalyst deactivation begins at the inlet of the first Reactor and proceeds slowly as a rather sharp front downward through the bed. The adverse effect that such deactivation can have on unit on-stream efficiency is avoided by installing two reactors in series. Each reactor contains 50% of the total required catalyst. Piping and valving are arranged to permit isolation of the reactor containing the spent catalyst while the second reactor remains in operation. After the spent catalyst has been replaced, the relative processing positions of the two reactors are reversed. During the short time when one reactor is off-line for catalyst replacement, the second reactor is fully capable of maintaining continuous operation at design throughput, yield, and conversion.
The reactor effluent flows to stabilizer after passing through the heat exchanger. The stabilizer overhead vapors are caustic scrubbed for removal of the HCl formed from organic chloride added to the reactor feed to maintain catalyst activity. After scrubbing, the overhead gas then flows to fuel. The stabilized, isomerized liquid product from the bottom of the column then passes to gasoline blending.
The Penex process (see below) uses the most active chlorided-alumina catalyst and operates in the range 120-180°C.
16
Chapter 2
Isomerization Techniques
LHSV is set during the design phase of any isomerization project and reflects the compromise between residence time and overall catalyst cost. At lower LHSVs, more catalyst is loaded resulting in a longer residence time. As a result lower temperature Operation is possible, resulting in a higher octane product.
System pressure is another variable and is considered in conjunction with the hydrogen flow rate to the reactor. Chlorided-alumina is more active at higher pressures. It requires only a slight excess over stoichiometric hydrogen, since the catalyst does not produce coke. A Penex unit operates at about 30 to 32 bar with oncethrough hydrogen.
Figure 2.2 (Block flow diagram of ―one through‖ process) To achieve higher octane, UOP offers several schemes in which lower octane components are separated and recycled back to the reactors. These recycle modes of operation can lead to product octane as high as 93 RON.
2.1.7
Penex Process/DIH (De-isoHexanizer):
This flow scheme is same as Penex Process with an addition of deisohexanizer column to recycle the methylpentanes, n-hexane, and some C6 cyclics. It is the lowest cost option of the recycle flow schemes & provide high octane isomerate product, especially on C6 rich feed.
17
Chapter 2
Isomerization Techniques
Figure 2.3 (Block flow diagram of process with DIP) 2.1.8
Penex Process With Recycle And Fractionation (DIP/Penex Process/DIH):
Separation and recycle of unconverted normal C5 and C6 paraffins and low octane C6 isoparaffins back to the reactor, produce a higher octane product. The most common flow scheme uses a deisohexanizer (DIH) column to recycle methylpentanes, nhexane, and some C6 cyclics. It is the lowest capital cost option of the recycle flow schemes and provides a higher octane isomerate product, especially on C6 rich feeds. In the Penex/DIH process the stabilized isomerate is charged to a DIH column producing an overhead product containing all the C5 and dimethylbutanes. Normal hexane and some of the methylpentanes are taken as a side-cut and recycled back to the reactors. The small amount of bottoms (C7+ and some C6 cyclics) can be sent to gasoline blending or to a reformer . The addition of a deisopentanizer (DIP) or a super DIH will achieve the highest octane from a fractionation hydrocarbon recycle flow scheme. In this scheme, both low octane C5 and normal and isoparaffin C6 are recycled to the Penex reactors.
Figure 2.4 (DIP-Penex-DIH) 18
Chapter 2
2.1.9
Isomerization Techniques
Penex/Molex Process:
Figure 2.5 (Penex/Molex Process flow scheme)
2.2 PROCESS DESCRIPTION: This flow scheme uses Molex technology for the economic separation and recycle of n-paraffin from the reactor effluent.
The Molex process is an adsorptive separation method that utilizes molecular sieves for the separation of n-paraffins from branched and cyclichydrocarbons. The separation is effected in the liquid phase under isothermal conditions according to the principles of the UOP Sorbex separations technology. Because the separation takes place in the liquid phase, heating, cooling and power requirements are remarkably low.
Sorbex is the name applied to a particular technique developed by UOP for separating a component or group of components from a mixture in the liquid phase by selective adsorption on a solid adsorbent.
Sorbex is a simulated moving bed adsorption process operating with all process streams in the liquid phase and at constant temperature within the adsorbent bed. Feed is introduced and components are adsorbed and separated from each other within the bed. A separate liquid of different boiling point referred to as ‗desorbent‘ is used to 19
Chapter 2
Isomerization Techniques
displace the feed components from the pores of the adsorbent. Two liquid streams emerge from the bed – an extract and a raffinate stream, both diluted with desorbent. The desorbent is removed from both product streams by fractionation and is recycled to the system.
The adsorbent is fixed while the liquid streams flow down through the bed. A shift in the positions of liquid feed and withdrawal, in the direction of fluid flow through the bed, simulates the movement of solid in the opposite direction. It is, of course, impossible to move the liquid feed and withdrawal points continuously. However, approximately the same effect can be produced by providing multiple Liquid access lines to the bed, and periodically switching each net stream to the next adjacent line. A liquid circulating pump is provided to pump liquid from the bottom outlet to the top inlet of the adsorbent chamber. A fluid-directing device, known as a ‗rotary valve‘, is also provided.
Figure 2.6 (BFD of Molex Process)
2.2.1
Operating Conditions Of Molex Process:
Molex unit involves three processes. a) Adsorption b) Purification c) Desorption
20
Chapter 2
Isomerization Techniques
2.2.1.1 Adsorption Operation:
The adsorbent employed in Molex is a specially prepared molecular sieve with selective pores. Molex feed enter the adsorbent chamber via rotary valve. Adsorbent chamber is operated at pressure 15 kg/cm2. 2.2.1.2 Purification Operation:
Non-normal paraffins (iso-paraffins) are removed from the adsorption chamber & purified in raffinate column. Operating temperature & pressure of raffinate column is 125 °C & 13.0 kg/cm2. 2.2.1.3 Desorption: Operating temperature & pressure of the extract column 130 °C & 16.0 kg/cm2. 2.2.2 Penex-Plus Technology The performance of the Penex process can be compromised when processing this feedstock because benzene hydrogenation is a highly exothermic reaction. The heat generated by the benzene hydrogenation reaction can cause the reactors to operate at conditions that are less favorable for octane upgrading. For these applications, UOP offers the Penex-Plus Technology.
It includes two reactor sections. The first section is designed to saturate the benzene to cyclohexane. The second section is designed to isomerize the feed for an overall octane increase. Each reactor is operated at conditions that favor the intended reactions for maximum conversion.
21
Chapter 2
Isomerization Techniques
2.3 OCTANE COMPARISON FOR DIFFERENT PROCESSES:
Figure 2.7 (Octane Comparison for different Processes) {Feed RON = 60 to 70
22
CHAPTER 3
PROCESS DESCRIPTION
Chapter 3
Process Description
CHAPTER # 3 PROCESS DESCRIPTION 3.1
SIMPLE PROCESS DESCRIPTION:
The isomerization of light paraffins is an important industrial process to obtain branched alkanes which are used as octane boosters in gasoline. Thus, isoparaffins are considered an alternative to the use of oxygenate and aromatic compounds, whose maximum contents are subjected to strict regulations in order to protect the environment. The UOP‘s Penex process is specifically designed for the catalytic isomerization of pentane, hexanes, and mixtures thereof. The reactions take place in the presence of hydrogen, over a fixed bed of catalyst, and at operating conditions that promote isomerization and minimize hydrocracking. Operating conditions are not severe, reaction takes place at moderate operating pressure, low temperature, and low hydrogen partial pressure is required.
Light naphtha feed is charged to one of the two dryer vessels. These vessels are filled with molecular sieves, which remove water and protect the catalyst. After mixing with makeup hydrogen, the feed is heat-exchanged against reactor effluent. It then enters a charge heater before entering the reactors. Two reactors normally operate in series. The reactor effluent is cooled before entering the product stabilizer. Only a slight excess of hydrogen above chemical consumption is used. The makeup hydrogen, which can be of any reasonable purity, is typically provided by a catalytic reformer. The stabilizer overhead vapors are caustic scrubbed for removal of the HCl formed from organic chloride added to the reactor feed to maintain catalyst activity. After scrubbing, the overhead gas then flows to fuel. The stabilized, isomerized liquid product from the bottom of the column then passes to gasoline blending.
Ideally, this isomerization catalyst would convert all the feed paraffins to the high octane- number branched structures: normal pentane (nC5) to isopentane (iC5) and
23
Chapter 3
Process Description
normal hexane (nC6) to 2,2- and 2,3-dimethylbutane. The reaction is controlled by a thermodynamic equilibrium that is more favorable at low temperature.
With C5 paraffins, interconversion of normal pentane and isopentane occurs. The C 6paraffin isomerization is somewhat more complex. Because the formation of 2- and 3methylpentane and 2,3-dimethylbutane is limited by equilibrium, the net reaction involves mainly the conversion of normal hexane to 2,2-dimethylbutane. All the feed benzene is hydrogenated to cyclohexane, and a thermodynamic equilibrium is established between methylcyclopentane and cyclohexane. The octane rating shows an appreciation of some 14 numbers. 3.2
PROCESS CHEMISTRY:
Isomerization mechanism and Kinetics Paraffin isomerization is most effectively catalyzed by a dual-function catalyst containing a noble metal and an acid function. The reaction is believed to proceed through an olefin intermediate that is formed by the dehydrogenation of the paraffin on the metal site. We use butane for simplicity CH3 — CH2 — CH2 — CH3 ↔ CH3 — CH2 — CH ═ CH2 + H2 These dual-functional hydro-isomerization catalysts which operate at very low temperatures have stronger acid site. In this case it is possible that the necessary carbonium ion is former by direct hydride ion abstraction from the paraffin by the acid function of the catalyst: CH3 — CH2 — CH ═ CH2 + [H+][A-] → CH3 — CH2 — CH+ — CH3 + A Then carbonium ion undergoes skeletal isomerization. However this reaction proceeds with difficulty because it requires the formation of a primary carbonium ion at some point in the reaction. Nevertheless, the strong acidity of the isomerization catalyst provides enough driving force for the reaction to proceed at high rates. + + CH3 — CH2 — CH — CH3 → CH3 — C — CH3 │ CH3 The isoparaffinic carbonium ion is then converted to an olefin through loss of a proton to the catalyst site. 24
Chapter 3
Process Description
+ CH3 — C — CH3 + A- → CH3 — C ═ CH2 + [H+][A-] │ │ CH3 CH3 In the last step, the isoolefin intermediate is hydrogenated rapidly back to the analogous isoparaffin:
CH3 — C ═ CH2 + H2 → CH3 — CH — CH3 │ │ CH3 CH3 Equilibrium limits the maximum conversion possible at any given set of conditions. This maximum is a strong function of the temperature at which the conversion takes place. A more favorable equilibrium exists at lower temperatures.
Figure 3.1 shows the equilibrium plot for the pentane system. The maximum isopentane content increases from 64 mol % at 260°C to 82 mol % at 120°C (248°F). Neopentane and cyclopentane have been ignored because they seem to occur only in small quantities and are not formed under isomerization conditions.
The hexane equilibrium curve shown in Figure 3.2 is somewhat more complex than that shown in Fig. 3.3. The methylpentanes have been combined because they have nearly the same octane rating. The methylpentane content in the C6-paraffin fraction remains nearly constant over the entire temperature range. Similarly, the fraction of 2,3-dimethylbutane is almost constant at about 9 mol % of the C6 paraffins. Theoretically, as the temperature is reduced, 2,2-dimethylbutane can be formed at the expense of normal hexane. This reaction is highly desirable because nC6 has a RON of 30. The RON of 2,2- dimethylbutane is 93.
25
Chapter 3
Process Description
Figure 3.1 C5 paraffin equilibrium plot
Figure 3.2 Equilibrium composition of hexane isomers in relation to temperature.
3.3
REACTIONS:
The C5/C6 paraffin isomerization reactions which occur in Penex unit are shown below:
26
Chapter 3
3.3.1
Process Description
Hexane Reactions Normal Hexane
2-Methyl Pentane CH3
CH3—CH2—CH2—CH2—CH2—CH3
↔ CH3—CH—CH2—CH2—CH3
24.8 RON
73.4 RON
3-Methyl Pentane CH3 CH3—CH2—CH2—CH2—CH2—CH3
↔ CH3—CH2—CH—CH2—CH3 74.5 RON
2-2 Dimethyl Butane CH3 CH3—CH2—CH2—CH2—CH2—CH3
↔ CH3—C—CH2—CH3 CH3 91.8 RON
2-3 Dimethyl Butane CH3 CH3—CH2—CH2—CH2—CH2—CH3
↔ CH3—CH—CH—CH3 CH3 104.3RON
27
Chapter 3
3.3.2
Process Description
Pentane Reaction
Normal Pentane
Iso-Pentane CH3
CH3—CH2—CH2—CH2—CH3 ↔ CH3—CH—CH2—CH3 61.8 RON
3.3.2
93.0 RON
Other Reactions
Apart from the paraffins isomerization reactions, there are several other important reactions including:
Naphthene Ring Opening
Naphthene Isomerization
Benzene Saturation
Hydrocracking
3.3.2.2 Ring Openinig: The three naphthenes which are typically present in feed are cyclopentane (CP), methyl cyclopentane (MCP) and cyclohexane (OH). The naphthene rings will hydrogenate to form paraffins. This ring opening reaction increases with increasing reactor temperature. At typical isomerization reactor conditions the conversion of naphthenes rings to paraffins will be on the order of 20-40 percent.
28
Chapter 3
Process Description
3.3.2.3 Naphthene Isomerization: The naphthenes Methyl Cyclopentane (MCP) and Cyclo Hexane (CH) exists in equilibrium. Naphthene isomerization will shift towards MCP production as temperature is increased.
3.3.2.4 Benzene Saturation: The catalyst will saturate benzene to cyclohexane. This reaction proceeds very quickly and is achieved at very low temperatures. Saturation a benzene is not equilibrium limited at the isomerization reactor conditions ant conversion should be 100%. The amount of heat generated by the saturation of benzene limits the amount of benzene which can be tolerated in the feed. The isomerization section feed can contain up to 5% benzene. The platinum function on the isomerization catalyst is responsible for benzene saturation.
3.3.2.5 Hydrocracking: Hydrocracking occurs in the reactors to a degree which depends on the feed quality and severity of operation. Large molecules such a C7‘s tend to hydrocrack more easily than smaller molecules. C5 and C6 paraffin will also hydrocrack to a certain extent. As C5/C6 paraffin isomerization approaches equilibrium, the extent of hydrocracking increases. If isomerization is pushed too hard, hydrocracking will reduce the liquid yield and increase heat production. Methane, ethane, propane and butane are produced as a result of hydrocracking.
29
Chapter 3
Process Description
Normal Heptane
Propane
i Butane CH3
CH3—CH2—CH2—CH2—CH2—CH2—CH3 → CH3—CH2—CH3 + CH3—CH—CH3
3.3.3
Chloride promoter:
The addition of the chloride promoter (perchloroethylene C2Cl4) to the process stream is intended to maintain the acid function of the catalyst with chloride atoms (Cl). At a reactor temperature of 105°C (220°F) or higher, the organic chloride will decompose to HCl in the presence of the catalyst. Perchloroethylene + Hydrogen → Hydrogen Chloride + Ethane C2Cl4 + 5H2 → 4HCl + C2H6 3.3.4
Caustic Scrubbing Reactions:
The hydrogen chloride formed in the isomerization reactors is neutralized in the Stabilizer Net Gas Scrubber, by means of an acid-base reaction between sodium hydroxide (NaOH) and hydrogen chloride (HCl). The result of this neutralization reaction is sodium chloride (NaCl) and water. The strength of the caustic should be monitored by determining the total alkalinity of the solution. Report the concentration of strong base as wt% NaOH. HCl + NaOH NaCl + H2O
3.4
PROCESS VARIABLES:
In the normal operation of a Penex Unit, having once set the operating pressure fresh feed rate and makeup hydrogen flows, it is usually only necessary to adjust the reactor inlet temperatures.
Once the catalyst has been loaded into the unit, the manner in which the catalyst it placed in seance and the treatment it receives when in service will to a large extent influence its effectiveness for making quality product as well as the length of service 30
Chapter 3
Process Description
it will give. In making any changes to the operation, the welfare of the catalyst must be given prime consideration for it can be regarded as the heart of the operation or which the quality of the results obtained will depend. 3.4.1
Reactor Temperature:
In general, reactor temperature is the main process control. A definite upper limit exists for the amount of iso-paraffins which can exist in the reactor product at any given outlet temperature, as shown in Figures 3.3, 3.4 and 3.5. This is the equilibrium imposed by thermodynamics, and can be reached only after an infinity length of time, i.e. with an infinitely large reactor. In practice, therefore, the product will contain less than this equilibrium concentration of iso-paraffins. As reactor temperature is raised to increase the rate of isomerization, the equilibrium composition will be approached more closely. At excessively high temperatures, the concentration of iso-paraffins in the product will actually decrease because of the downward shift in equilibrium curve, even though the high temperature gives a high reaction rate.
The use of temperatures higher than necessary to achieve a reasonably close approach to equilibrium accomplishes nothing other than to increase the amount of hydrocracking. Extremely high temperatures may lead to an increased rate of carbon laydown on the catalyst; however, the carbon forming propensity of the catalyst is inherently so low that excessive hydrocracking would normally be encountered before carbon formation problems would develop. It is recommended, however, that UOP be consulted before temperatures above about 204°C (400°F) are employed.
A typical C5/C6 Penex Unit has two series reactors with provision for independent temperature control. The first reactor system effects the bulk of the isomerization so long as most of the catalyst therein is still active. Any benzene in the feed it hydrogenated in the first reactor, even when the catalyst therein has lost its activity with respect to paraffin isomerization. Some conversion, ring opening, of cyclohexane and methyl Cyclopentane to hexanes also occurs, as does some hydrocracking of C7 to C3 and C4. These three reactions (benzene hydrogenation, naphthene ring opening to hexane, and C7 hydrocracking) are exothermic and, for a typical feed stock contribute more to the temperature rise in the first reactor that does paraffin isomerization, which is also exothermic. 31
Chapter 3
Process Description
Normally, the first reactor system will be operated at such a temperature as to maximize the concentration of isopentane and 2,2 dimethyl butane in its effluent. The concentrations attainable and the required outlet temperature will be influenced by the amount of active catalyst present and by the amount of C6 cyclic and C7 components present in the feed, higher the temperatures being required with high concentrations of these components in the feed. By this procedure, the required operating temperature on the second reactor system is reduced and it is possible to operate under conditions where the equilibrium is more favorable.
Figure 3.3 Iso-pentane equilibrium curve
32
Chapter 3
Process Description
Figure 3.4 2-2Dimethyl butane Equilibrium curve
Figure 3.5 Equilibrium Curve
33
Chapter 3
3.4.2
Process Description
Liquid Hourly Space Velocity:
This term, commonly shortened to LHSV, is defined as the volumetric hourly flow of reactor charge divided by the volume of catalyst contained in the reactors in consistent units. The design LHSV for C5/C6 Penex operation is normally between 1 and 2. Increasing the LHSV beyond this will lead to lower product isomer ratios. In order to avoid excessive reactor severity, the Penex reactor LHSV should always be maintained above 0.5 hr-1 overall or 1.0 LHSV minimum per reactor. 3.4.3
Hydrogen to Hydrocarbon Mole Ratio:
This ratio is defined as the number of moles hydrogen at the reactor outlet per mole of reactor charge passing over the catalyst, and is specified at 0.05 moles H2/mole HCBN. The primary purpose of maintaining the ratio at or above the design is to avoid carbon deposition on the catalyst and maintain enough H2 for the reactions to proceed. If necessary, the reactor charge rate is to be reduced to maintain the design hydrogen to hydrocarbon ratio. The H2/HCBN ratio is determined by measuring the total mole of hydrogen in the stabilizer overhead gas and dividing by the total moles of fresh feed feedstock. 3.4.4
Pressure:
C5/C6 Penex Units are normally designed to operate at 31.6 kg/cm2 gauge (450 psig) at the reactor outlet. Methylcyclopentane and cyclohexane appear to adsorb on the catalyst and reduce the rate of isomerization reactions. Higher pressure helps to offset this effect of the C6 cyclic compounds. Lowering the unit pressure or operating at a slightly lower level would not affect the catalyst life but the extent of isomerization would be influenced. 3.4.5
Catalyst Promoter:
To sustain catalyst activity, the addition of chloride is necessary. At no time should the plant be operated for longer than six hours without the injection of chloride. Whenever there is a catalyst chloride deficiency, the product isomer ratios will decrease (although not necessarily instantaneously), other things being equal. Restarting the injection of chloride will tend to return the activity of the catalyst to its previous level, but it is possible that full activity will not be restored if a decline in 34
Chapter 3
Process Description
activity as a result no chloride injection has been observed. Isomerization grade perchloroethylene (C2Cl4) is UOP's recommended source of chloride.
3.5
PROCESS EQUIPMENTS:
3.5.1
Sulfur Guard Bed:
The purpose of the sulfur guard bed is to protect the Penex catalyst from sulfur in the liquid feed. The hydrotreater will remove most of the sulfur in the Penex feed. The guard bed reduces the sulfur to a safe level for operation and serves as insurance against upsets in the NHT which could result in higher that formal level of sulfur in the feed. The guard bed is loaded with an adsorbent, a nickel containing extrudate designed to chemisorb sulfur from the liquid feed. The feedstock is heated to the required temperature for sulfur removal, usually 121 °C (250°F), and passed down flow over the adsorbent.
Once sulfur breakthrough occurs, normally after one year or so of operation, the guard bed is taken off line and reloaded with fresh adsorbent. The Penex Unit need not be shut down during the short period of time required to reload the guard bed so long as the NHT is performing properly. 3.5.2
Liquid Feed Driers:
The purpose of the liquid feed driers is to ensure that the hydrocarbon stream from the treating section is dry before entering the Penex Unit.
The driers are operated in series except when they are in the regeneration mode when at that time only one will be in service.
The hydrotreated C5/C6 stream is introduced to the liquid feed drier at the bottom and passes up flow through the molecular sieve desiccant and exits at the top. The flow is then routed through one of the drier crossovers to the other liquid feed drier. The flow through the liquid feed drier is also in the up flow pattern. The dried hydrocarbon is then routed to feed surge drum. Over a period of time, the drier in the lead position 35
Chapter 3
Process Description
will become spent as indicated by the moisture analyzer located between the two driers. At this time, it will become necessary to regenerate this drier. The driers should be regenerated on a schedule frequent enough to avoid moisture breakthrough. The spent drier is taken out of service by closing the appropriate block valves. The second series drier is now alone in service as the only drier drying the feed. The moisture analyzer tap is switched to monitor this in service drier. After the drier regeneration has been completed, it is now ready for service. A switch is made such that the regenerated drier takes the tail position with the in-service drier remaining as the lead drier. Over a period of time the lead drier will become spent and is now set up far regeneration with the tail drier now being the only one in service. This will be the manner in which these driers will be lined up for process flow.
3.5.3
Make-up Gas Driers:
Make-up gas must be dried in order to protect the catalyst. The two gas driers operate in the same manner as the liquid feed driers. The driers operate up flow, in series. The dried hydrogen is then sent to the reactor circuit on flow control. The hydrogen is also used for pressure control in the feed surge drum and, for startup, in the stabilizer. 3.5.4
Feed Surge Drum:
The purpose of this drum is to provide liquid feed surge capacity for the Penex Unit. Dried feed from the liquid feed driers is routed to this drum. The feed surge drum is blanketed with dry hydrogen gas originating from the outlet of the make-up gas driers with the feed surge drum pressure being controlled by a PRC. 3.5.5
Reactor Exchanger Circuit:
The dried liquid feed from the feed surge drum is pumped by either of the t reactor charge pumps through the reactor exchanger circuit on flow control. The reactor exchanger circuit consists of the cold combined feed exchanger, the hot combined feed exchanger and the reactor charge heater.
Prior to the entry of the liquid hydrocarbon into the cold combined feed exchanger, it combines with the makeup hydrogen stream. After combining, the mix hydrocarbon-
36
Chapter 3
Process Description
hydrogen stream passes through the exchanger circuit in the order previously mentioned. The cold combined feed exchanger is equipped with a bypass which can be used to regulate the amount of combined feed preheat. The bypass is regulated with a board mounted control valve to maintain reactor charge heater control. The combined feed is further preheated by exchange with a portion of the lead reactor effluent in the hot combined feed exchanger.
A small quantity of catalyst promoter (perchloroethylene) is added upstream of the reactor charge heater. This promoter is pumped into the process by either of two injection pumps. The catalyst promoter is stored in a nitrogen blanketed storage drum.
The combined feed is finally brought up to the desired temperature in the reactor charge heater by a temperature controller which resets the exchanger‘s heat medium flow. The charge heater is equipped with an automatic shutdown which is activated by low feed or low makeup gas flow.
After exiting the reactor charge heater, the heated combined stream then flows into the first reactor. 3.5.6
Regenerant Vaporizer:
The regenerant vaporizer uses low pressure steam to heat the regenerant stream before it reaches the electric superheater. The vaporizer is an upright heat exchanger which uses bayonet type tubes that have been strength welded and fully rolled. This heater is equipped with a level indicator and a high level alarm, and is designed to operate with the top portion of the tubes uncovered. Low pressure steam on the inside of the bayonet tubes transfers heat to the regenerant on the outside of the bayonet tubes. This arrangement allows hot stream in the tip of the bayonet tube to transfer heat to the vaporized regenerant stream, giving it several degrees of superheat. This prevents the regenerant from condensing which could damage the electric bundles in the super heater when operating.
37
Chapter 3
3.5.7
Process Description
Regenerant Superheater:
The regenerant superheater, raises the temperature of the vaporized regenerate to a temperature of 315°C (600°F). The regenerant stream is heated by Inconel electric elements, which are capable of reaching temperatures of over 600°C (1112°F).The regenerant entering the superheater must be in the vapor phase to avoid damaging the electric bundles when power is applied to the superheater.
3.5.8
Isomerization Reactors:
The reactors are the heart of the process. The operation of them is such that, reactor will be placed in series with the other reactor. At various times throughout the unit's history it will be possible to have either reactor in the lead or tail position. A single reactor bypass allows operation of one reactor only during startup or partial catalyst replacement. Thermocouples are inserted into the catalyst bed of each reactor to monitor the activity of the catalyst in conjunction with product ratios.
After exiting the reactor charge heater, the heated combined stream then flows to the first reactor. Upon exiting the first reactor, the stream then passes to the hot combined feed exchanger where the first reactor's heat of reaction is partially removed. The degree of temperature removal can be achieved by adjusting the amount of exchanger by-passing with a temperature controller. This temperature controller fixes the lag reactor's inlet temperature.
The partially cooled stream is then routed to the second reactor where the find process reactions are completed. The reactors are equipped with hydrogen purge lines which are located at the inlet of each reactor. The hydrogen purge is used to remove hydrocarbon from a reactor which is to be unloaded or to pressurize a reactor. A hydrogen quench line is located at the lead reactor inlet header to aid in cooling the catalyst during a temperature excursion as well as removing hydrocarbon. The quench is controlled by an HIC with flow indication.
38
Chapter 3
Process Description
In case of a high reactor temperature emergency, the reactors are equipped with depressuring lines to the flare system. The reactors are depressured from the outlet of the lag reactor. The depressuring line is equipped with two motorized o pneumatically operated valves which can be operated from the control room once the reactors have been isolated from the charge heater and stabilizer.
After exiting the second reactor, the stream is then routed to the tube side of the cold combined feed exchanger. The cold combined feed exchanger tube side effluent is then routed to the stabilizer on pressure control. 3.5.9
Stabilizer:
The purpose of this column is to separate any dissolved hydrogen, HCI and cracked gases (C1, C2, and C3's) from the isomerate. The feed to this column is routed hot directly from the cold CFX before entering the stabilizer.
The column is reboiled by either steam or hot oil. The reboiler heat input is controlled by an FRC on the heating medium. The amount of heat input is adjusted to maintain sufficient reflux to adequately strip the HCl and light ends from the stabilizer bottoms material. The typical design external reflux to feed ratio is approximately 0.5 on a volume basis and is recommended as a starting point.
The stabilizer column overhead vapor, consisting of the light hydrocarbon components of the column's feed, is routed to an air or water cooled condenser and then to the stabilizer receiver. To maintain pressure control on the column, gas is vented on pressure control to the stabilizer gas scrubber. Liquid is pumped from the receiver on level control with the stabilizer reflux pump. All liquid from the stabilizer overhead receiver is refluxed to the column on tray No. 1. Bottoms product is routed to storage on level control after first being cooled in the stabilizer bottoms cooler. If the stabilizer bottoms is sent to a deisohexanizer it is not cooled, but is charged hot to the column. Part of the stabilizer bottoms is used for regenerating the driers. 39
Chapter 3
Process Description
3.5.10 Stabilizer Net Gas Scrubber: The function of the Stabilizer Net Gas Scrubber is to neutralize the hydrogen chloride present in the Stabilizer off Gas prior to its entry into the fuel gas system o the flare header. The HCI is formed in the reactor section and then vented off through the Stabilizer Overhead Receiver, to the Stabilizer Net Gas Scrubber. In this vessel, the off gas from the Stabilizer Receiver is contacted through a liquid level and later with a counter current flow of caustic solution (10 wt. % NaOH) which reacts with HCl to form sodium chloride and water. The entry point for the off gas is located at the bottom of the scrubber, and consists of a monel distributor with small holes to allow even gas distribution. The bottom distributor and the inlet flange are both made of monel to prevent corrosion, resulting from contact with high concentrations of HCl in an aqueous environment. The vessel is constructed of killed carbon steel.
The top portion of the vessel is filled with 25mm (1‘‘) Carbon Raschig Rings, which provide a good contact area for the interaction of the liquid caustic and the acidic overhead gas. The packing in the scrubbing section is held in place by a support orating on the bottom and a hold down grating on the top.
The incoming gas is contacted with the caustic in the bottom portion of the scrubber or "reservoir" section. This is where most of the HCl is removed before it reaches the top portion or the scrubbing section of the column. A high level of caustic solution is usually kept in the reservoir section of the column to ensure that there is always an ample supply of caustic for circulation. A pump is used to circulate the caustic to the two infection points on the scrubber column. One injection point if located at the top of the packed section (a spray nozzle or slot type distributor) ant the other is located just below the packed section (a spray nozzle or ring type distributor). The purpose of the lower spray distributor is to direct the caustic flow to the conical walls of the scrubber to keep the walls wetted with caustic. The design flow of caustic should be continuously maintained to each distributor to ensure goof flow distribution.
40
Chapter 3
Process Description
A water wash section may be included above the circulating caustic to remove entrained caustic from the net gas. Circulating water monitored by an FI is passed over a bed of 25mm (1‘‘) Carbon Raschig Rings at design rate. Makeup water is added to overflow a chimney trap tray which replaces water lost to saturating the dry gas in the caustic inventory section. The water is typically changed out if the caustic strength reaches 2 wt. % NaOH in the circulating water or if caustic entrainment is observed. 3.5.11 Pumps: Centrifugal pumps are used for several applications in the Penex Unit. Common applications for the centrifugal pumps are for reactor charge pumps, reflux pumps for the fractionation columns, and caustic recirculation pumps. Proportioning pumps are used for chloride injection into the feed stream and make-up water to the net gas scrubber.
Pumps used in hydrocarbon service use tandem seals with API 52 seal plans. In this application the seal oil circulation is established by way of a siphon. The seal oil is contained in a reservoir where it can be pumped to and from the pump seal. The oil is continuously pumped between the two seals. In the event of a seal failure, hydrocarbon will leak into the oil system and cause a pressure increase in the reservoir. The seal oil reservoir is equipped with a pressure alarm and pressure gauge to alert the operator to a seal failure. The reservoir is usually vented to flare through an orifice plate.
41
CHAPTER 4
CATALYST SELECTION
Chapter 4
Catalyst Selection
CHAPTER # 4 CATALYST SELECTION 4.1
CATALYST:
Substance that changes the rate of reaction but does not take part in reaction.
4.2
TYPES OF CATALYSTS:
The schemes of proposing processes are analogous generally. The differences are defines by performances of usable catalysts due to their type. Main parameter which is the octane number of produced isomerate depends on process temperature. That‘s why we will dwell on the issue of thermodynamic of isomerization reaction. First of all hydrocarbons isomerization reaction is balanced reaction, and equilibrium yield of isoparaffins increases with temperature reducing, but it can be reached only after an ―infinite residence time‖ of the feed in reaction zone or an equivalent very small value for LHSV. On the other hand an increase in temperature always corresponds to an increase in reaction velocity. So that at low temperature the actual yield will be far below the equilibrium yield, because of low reaction velocity. On the contrary, at higher temperature, the equilibrium yield will be more easily reached, due to a high reaction rate. Consequently, at higher temperature the yield of isoparaffins is limited by the thermodynamic equilibrium, and at lower temperature it is limited by low reaction rate (kinetic limitation) (Figure 4.1)
Figure 4.1 Dependence of n-paraffins conversion on reaction temperature 43
Chapter 4
Catalyst Selection
Paraffin-isomerization catalysts fall mainly into two principal categories: those based on Friedel-Crafts catalysts as classically typified by aluminum chloride and hydrogen chloride and dual-functional hydro isomerization catalysts. 4.2.1
First Generation Catalysts:
The Friedel-Crafts catalysts represented a first-generation system. Although they permitted operation at low temperature, and thus a more favorable isomerization equilibrium, they lost favor because these systems were uneconomical and difficult to operate. High catalyst consumption and a relatively short life resulted in high maintenance costs and a low on-stream efficiency. 4.2.2
Second Generation Catalysts:
These problems of first generation systems were solved with the development of second-generation dual-functional hydro isomerization catalysts. These catalysts included a metallic hydrogenation component in the catalyst and operated in a hydrogen environment. However, they had the drawback of requiring a higher operating temperature than the Friedel-Crafts systems. 4.2.3
Third Generation Catalysts:
The desire to operate at lower temperatures, at which the thermodynamic equilibrium is more favorable, dictated the development of third-generation catalysts. The advantage of these low-temperature [below 200°C (392°F)] catalysts contributed to the relative nonuse of the high-temperature versions. Typically, these noble-metal, fixed-bed catalysts contain a component to provide high catalytic activity. They operate in a hydrogen environment and employ a promoter. Because hydrocracking of light gases is slight, liquid yields are high.
An improved version of these third-generation catalysts is used in the Penex process. Paraffin isomerization is most effectively catalyzed by a dual-function catalyst containing a noble metal and an acid function. The reaction is believed to proceed through an olefin intermediate that is formed by the dehydrogenation of the paraffin on the metal site.
44
Chapter 4
4.2.4
Catalyst Selection
Aluminum Chloride:
The isomerization catalysts employed during World War II were all of the Friedel Crafts type. Those which contained aluminum chloride only were either a hydrocarbon/aluminum chloride complex (the so-called sludge process) or they were manufactured in-situ by deposition onto a support such as alumina or bauxite. They were intended to operate at very low temperatures [49-129°C (120-265°F)] and to approach the very favorable equilibrium composition characteristic of these temperatures.
The catalyst tended to consume itself by reaction with the feedstock and/or product. When temperature was raised a little in an effort to compensate for loss of catalyst and to speed the reaction to effect more isomerization, light fragments were formed by cracking and these, when vented caused an excessive loss of the HCI promoter.
Corrosion of downstream equipment was also commonplace, due to the solubility of aluminum chloride in hydrocarbon, to its relatively high volatility and to the difficulty of removing it from the product by caustic washing. Aluminum chloride deposition in and plugging of reboiler tubes was not uncommon. 4.3
DUAL-FUNCTIONAL HYDROISOMERIZATION CATALYSTS:
4.3.1
Hydro-isomerization catalysts [above 199°c (390°f)]:
The operational problems which had characterized the Friedel-Crafts type isomerization plants, the advent of catalytic reforming which not only made hydrogen generally available in refineries but also demonstrated the practicality of using noble metal containing catalysts on a large scale, and the octane numbed race which postwar high compression engines initiated all combined in the 1950's to spawn a spate of hydro-isomerization processes. These catalysts generally contained a noble metal and some halide, operated at temperatures between about
299°C (560°F) and
temperatures approaching those characteristic of catalytic reforming, employed recycle hydrogen to prevent catalyst carbonization and utilized either no promoter or traces at most. In general, they did not require an especially dry feedstock but did benefit from a low sulfur content feedstock. Most achieved a close approach to the equilibrium characteristic of their particular operating temperature. 45
Chapter 4
Catalyst Selection
Because of their high operating temperatures and their necessarily low conversions to iso-paraffins, these high temperature catalysts were quickly replaced with the advent of the ―third generation‖ low temperature catalysts. 4.3.2
Hydro-isomerization catalysts [below 199°c (390°f)]:
Low temperature is considered rather arbitrarily for catalyst classification purposes as anything below 199°C (390°F) operating temperature. Typically these are fixed bed catalysts containing a supported noble metal and a component to provide acidity in the catalytic sense. They operate in a hydrogen atmosphere and may employ a catalyst promoter whose concentration in the reactor may range from parts per million to substantially higher levels. They generally all require a dry, low sulfur feedstock; however, they may differ importantly in their tolerance of certain types and molecular weights of hydrocarbons. Hydrocracking to light gases is generally slight, so liquid product yields are high. The type of catalyst used in the Penex unit is of this type.
The acid function is the support itself and some examples include acid zeolites, chlorided alumina and amorphous silica alumina. Noble metals have a positive effect on the activity and stability of the catalyst. However they have a low resistance to poisoning by sulfur and nitrogen compounds present in the processed cuts.
In order to prepare a suitable catalyst for hydroconversion of alkanes, good balance between the metal and acid functions must be obtained. Rapid molecular transfer between the metal and acid sites is necessary for selective conversion of alkanes into desirable products. 4.4
ALUMINA CATALYST:
Alumina or aluminum oxide (AlR2ROR3R) is a chemical compound with melting point of about 2000°C and sp. gr. of about 4.0. It is insoluble in water and organic liquids and very slightly soluble in strong acids and alkalies. Alumina occurs in two crystalline forms. Alpha alumina is composed of colorless hexagonal crystals with the properties given above; gamma alumina is composed of minute colorless cubic
46
Chapter 4
Catalyst Selection
crystals with sp. gr. of about 3.6 that are transformed to the alpha form at high temperatures. Figure (4.2) shows the shape of AlR2ROR3R [Ulla, 2003]. The most common form of crystalline alumina, α-aluminum oxide, is known as corundum. If a trace of the element is present it appears red, it is known as ruby, but all other colorations fall under the designation sapphire. The primitive cell contains two formula units of aluminum oxide. The oxygen ions nearly form a hexagonal close-packed structure with aluminum ions filling two-thirds of the octahedral interstices.
Typical alumina characteristics include:
Good strength and stiffness Good hardness and wear resistance Good corrosion resistance
Good thermal stability
Excellent dielectric properties (from DC to GHz frequencies) Low dielectric constant Low loss tangent
Figure 4.2 Aluminum Oxide
47
Chapter 4
4.5
Catalyst Selection
CHLORINATED-ALUMINA BASED CATALYSTS:
These are the most active and supply the highest isomerize yield and isomerize octane.
Figure 4.3 Characteristics of chlorinated alumina catalysts 4.6
ZEOLITES:
Zeolites are micro porous crystalline solids with well-defined structures. Generally they contain silicon, aluminum and oxygen in their framework and cations, water and/or other molecules within their pores. Zeolites occur naturally as minerals or synthetic, Figure (4.3) shows the shape of different types of zeolites [Matthew, 2008]. Because of their unique porous properties, zeolites are used in a variety of applications with a global market of several million tons per annum. In the western world, major uses are in petrochemical cracking, ion-exchange (water softening and purification), and in the separation and removal of gases and solvents. Other applications are in agriculture, animal husbandry and construction. They are often also referred to as molecular sieves [Danny, 2002]. Zeolites have the ability to act as catalysts for chemical reactions which take place within the internal cavities. An important class of reactions is that catalyzed by hydrogen-exchanged zeolites, whose framework-bound protons give rise to very high acidity. This is exploited in many organic reactions, including crude oil cracking, isomerization and fuel synthesis [Jirong, 1990].
4.5.1
Zeolite Characteristics:
Well-defined crystalline structure. High internal surface areas (>600 m 2 /g). P
48
P
Chapter 4
Catalyst Selection
Uniform pores with one or more discrete sizes. Good thermal stability. Highly acidic sites when ion is exchanged with protons. Ability to sorb and concentrate hydrocarbons.
Figure 4.4 Structure and dimension of different types of zeolite
Figure 4.5 49
CHAPTER 5
MATERIAL BALANCE
Chapter 5
Material Balance
CHAPTER # 5 MATERIAL BALANCE
5.1
Material Balance:
Material balances are important first step when designing a new process or analyzing an existing one. They are almost always prerequisite to all other calculations in the solution of process engineering problems. Material balances are nothing more than the application of the law of conservation of mass, which states that mass can neither be created nor destroyed. Thus, you cannot, for example, specify an input to a reactor of one ton of naphtha and an output of two tons of gasoline or gases or anything else. One ton of total material input will only give one ton of total output, i.e. total mass of input = total mass of output. 5.1.1
Conservation Law:
Total flow rate of (S) into the system
+
Generation rate of (S) within system
=
Total flow rate of (S) out of the system
+
Accumulation rate of (S) within system
±
Amount of (S) exchanged with the surrounding
The quantity S can be any one of the following quantities: 5.1.2
Mass Energy Momentum Component Mass (Mole) Total Mass Balance:
Since mass is always conserved, the balance equation for the total mass (m) of a given system is: Rate of mass in - Rate of mass out = rate of mass accumulation 5.1.3
Component Balance:
The mass balance for a component A is generally written in terms of number of moles of A. Thus the component balance is: Flow of Flow of Rate of Rate of moles (A) + mole of (A) + Generation of = Accumulation of in out moles of (A) moles of (A) 50
Chapter 5
Material Balance
Basis: Naphtha Feed Stream 600 Barrel of Naphtha per stream day to be Isomerized Mass flow rate
=
25000 kg/hr
Molecular Weight
=
83.085
Density
=
660 kg/m3
Hydrogen Feed Stream Mass flow rate
=
732 kg/hr
Molecular Weight
=
7.907
Density
=
1.215 kg/m3
Equilibrium Data: Equilibrium Conversions are taken from the following curves
Figure 5.1 Thermodynamic equilibrium for the isomerization of heptane
51
Chapter 5
Material Balance
Figure 5.2 Thermodynamic equilibrium for the isomerization of Butane, pentane and hexane
52
Chapter 5
5.2
Material Balance
Mass Balance on Mixer
Stream 3 Molecular Mass
Mass Fraction
Mass Flow Rate
Molar Flow Rate
n C4
58.00
0.0267
667.50
11.51
nC5
72.00
0.1673
4182.50
58.09
nC6
86.00
0.1589
3971.25
46.18
n C7
100.00
0.0929
2321.75
23.22
iC5
72.00
0.1077
2693.25
37.41
2 MP
86.00
0.0750
1875.25
21.81
3 MP
86.00
0.0482
1204.25
14.00
2,2 DMB
86.00
0.0056
138.75
1.61
2,3DMB
86.00
0.0121
301.75
3.51
2 MH
100.00
0.0373
931.65
9.32
Components
3 MH
100.00
0.0373
931.40
9.31
2,2 DMP
100.00
0.0027
68.40
0.68
2,3 DMP
100.00
0.0112
279.15
2.79
2,4 DMP
100.00
0.0057
141.65
1.42
3,3 DMP
100.00
0.0018
43.93
0.44
3 EP
100.00
0.0028
69.90
0.70
C6 H 6
78.00
0.0253
632.50
8.11
C7 H 8
92.00
0.0288
719.25
7.82
CP
70.00
0.0118
295.50
4.22
MCP
84.00
0.0400
998.75
11.89
CH
84.00
0.0387
967.25
11.51
ECP
98.00
0.0028
70.00
MCH
98.00
0.0598
1494.50
Total
1.00
25000.08
53
0.71 15.25 301.51
Chapter 5
Material Balance
Stream 2
Components
Molecular Mass
Volume fraction
Mole Fraction
Mass
Mass Fraction
H2
2
0.78
0.780
1.56
0.1980
144.91
72.4569
C1
16
0.099
0.099
1.58
0.2010
147.14
9.1964
C2
30
0.064
0.064
1.92
0.2437
178.36
5.9452
C3
44
0.038
0.038
1.67
0.2122
155.32
3.5299
n-C4
58
0.008
0.008
0.46
0.0589
43.10
0.7431
i-C4
58
0.008
0.008
0.46
0.0589
43.10
0.7431
n-C5
72
0.002
0.002
0.14
0.0183
13.38
0.1858
i-C5
72
0.001
0.001
0.07
0.0091
6.69
0.0929
1.00
1.00
7.88
1.00
732.00
92.8934
Total
Stream 4 Components
Molecular Mass
Mass Fraction
Mole Fraction
Mass Flow Rate
Molar Flow Rate
H2
2.00
0.0056
0.1837
144.91
72.4569
C1
16.00
0.0057
0.0233
147.14
9.1964
C2
30.00
0.0069
0.0151
178.36
5.9452
C3
44.00
0.0060
0.0090
155.32
3.5299
n C4
58.00
0.0276
0.0311
710.60
12.2518
nC5
72.00
0.1631
0.1478
4195.88
58.2761
nC6
86.00
0.1543
0.1171
3971.25
46.1773
n C7
100.00
0.0902
0.0589
2321.75
23.2175
i-C4
58.00
0.0017
0.0019
43.10
0.7431
72.00 86.00 86.00 86.00 86.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 78.00 92.00 70.00 84.00 84.00 98.00 98.00
0.1049 0.0729 0.0468 0.0054 0.0117 0.0362 0.0362 0.0027 0.0108 0.0055 0.0017 0.0027 0.0246 0.0280 0.0115 0.0388 0.0376 0.0027 0.0581 1.00
0.0951 0.0553 0.0355 0.0041 0.0089 0.0236 0.0236 0.0017 0.0071 0.0036 0.0011 0.0018
2699.94 1875.25 1204.25 138.75 301.75 931.65 931.40 68.40 279.15 141.65 43.93 69.90 632.50 719.25 295.50 998.75 967.25 70.00 1494.50 25732.08
37.4991
iC5 2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6 H 6 C7 H 8 CP MCP CH ECP MCH
Total
0.0206 0.0198 0.0107 0.0301 0.0292 0.0018 0.0387 1.00
54
21.8052 14.0029 1.6134 3.5087 9.3165 9.3140 0.6840 2.7915 1.4165 0.4393 0.6990 8.1090 7.8179 4.2214 11.8899 11.5149 0.7143 15.2500 394.40
Mass Flow Molar Flow Rate Rate
Chapter 5
5.3
Material Balance
Material Balance around Reactors:
55
Chapter 5
Material Balance
Stream 7 Components
Molecular Mass
Mass Fraction
Mole Fraction
Mass Flow Rate
Molar Flow Rate
H2
2.00
0.0056
0.1837
144.91
72.4569
C1
16.00
0.0057
0.0233
147.14
9.1964
C2
30.00
0.0069
0.0151
178.36
5.9452
C3
44.00
0.0060
0.0090
155.32
3.5299
n C4
58.00
0.0276
0.0311
710.60
12.2518
nC5
72.00
0.1631
0.1478
4195.88
58.2761
nC6
86.00
0.1543
0.1171
3971.25
46.1773
n C7
100.00
0.0902
0.0589
2321.75
23.2175
i-C4
58.00
0.0017
0.0019
43.10
0.7431
iC5
72.00
0.1049
2699.94
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C 6 H6
86.00 86.00 86.00 86.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00
0.0729 0.0468 0.0054 0.0117 0.0362 0.0362 0.0027 0.0108 0.0055 0.0017 0.0027
0.0951 0.0553 0.0355 0.0041 0.0089 0.0236 0.0236 0.0017 0.0071 0.0036 0.0011 0.0018
37.4991 21.8052 14.0029 1.6134 3.5087 9.3165 9.3140 0.6840 2.7915 1.4165 0.4393 0.6990
78.00
0.0246
632.50
C7 H 8
92.00 70.00 84.00 84.00 98.00 98.00 18.00 94.00
0.0280 0.0115 0.0388 0.0376 0.0027 0.0581 0.0000 3.000E-06 1.00
0.0206 0.0198 0.0107 0.0301 0.0292 0.0018 0.0387 0.0000 0.0000
CP MCP CH ECP MCH H2 O C2Cl4 Total
1.00
56
1875.25 1204.25 138.75 301.75 931.65 931.40 68.40 279.15 141.65 43.93 69.90 719.25 295.50 998.75 967.25 70.00 1494.50 0.00 7.50E-05 25732.08
8.1090 7.8179 4.2214 11.8899 11.5149 0.7143 15.2500 0.0000 7.98E-07 394.40
Chapter 5
Material Balance
Stream 8
Components
Molecular Mass
Mass Fraction
Mole Fraction
Mass Flow Rate
Molar Flow Rate
H2
2.00
0.0013
0.0482
32.6411
16.3205
C1
16.00
0.0057
0.0272
147.4071
9.2129
C2
30.00
0.0070
0.0177
179.3759
5.9792
C3
44.00
0.0062
0.0107
159.0078
3.6138
n C4
58.00
0.0137
0.0180
353.4739
6.0944
nC5
72.00
0.0394
0.0416
1013.8848
14.0817
nC6
86.00
0.0362
0.0320
932.4828
10.8428
n C7
100.00
0.0072
0.0055
185.7398
1.8574
i-C4
58.00
0.0154
0.0202
396.9166
6.8434
iC5
72.00 86.00 86.00 86.00 86.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 78.00 92.00 70.00 84.00 84.00 98.00 98.00 100.00 18.00 94.00 36.50
0.2321 0.1192 0.0730 0.0455 0.0287 0.0600 0.0497 0.0162 0.0307 0.0136 0.0116 0.0045 0.0000 0.0000 0.0080 0.0252 0.0663 0.0027 0.0733 0.0072 0.0000 1.00E-06 2.30E-05 1.00
0.2451 0.1054 0.0646 0.0403 0.0254 0.0457 0.0378 0.0123 0.0233 0.0104 0.0088 0.0034
5971.2138 3066.6213 1879.3603 1171.2736 738.5866 1545.0732 1279.6610 416.6620 789.9341 350.6071 299.3171 116.3349 0.6325 0.7192 206.8498 649.1867 1707.1082 69.9999 1886.2642 185.7398 0.0000 0.0257 0.5918 25732.69
82.9335 35.6584 21.8530 13.6195 8.5882 15.4507 12.7966 4.1666 7.8993 3.5061 2.9932 1.1633
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C 6H6 C7 H 8 CP MCP CH ECP MCH 2,2,3 TMB H2 O C2Cl4 HCL Total
57
0.0000 0.0000 0.0087 0.0228 0.0601 0.0021 0.0569 0.0055 0.0000 0.0000 0.0000 1.0000
0.0081 0.0078 2.9550 7.7284 20.3227 0.7143 19.2476 1.8574 0.0000 0.0003 0.0162 338.32
Chapter 5
Material Balance
58
Chapter 5
Material Balance
Stream 9 Molecular Mass
Mass Fraction
Mole Fraction
Mass Flow Rate
Molar Flow Rate
H2
2.00
0.0013
0.0482
32.6411
16.3205
C1
16.00
0.0057
0.0272
147.4071
9.2129
C2
30.00
0.0070
0.0177
179.3759
5.9792
C3
44.00
0.0062
0.0107
159.0078
3.6138
n C4
58.00
0.0137
0.0180
353.4739
6.0944
nC5
72.00
0.0394
0.0416
1013.8848
14.0817
nC6
86.00
0.0362
0.0320
932.4828
10.8428
n C7
100.00
0.0072
0.0055
185.7398
1.8574
i-C4
58.00
0.0154
0.0202
396.9166
6.8434
iC5
72.00
0.2321
0.2451
5971.2138
82.9335
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C 6 H6
86.00 86.00 86.00 86.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00
0.1192 0.0730 0.0455 0.0287 0.0600 0.0497 0.0162 0.0307 0.0136 0.0116 0.0045
0.1054 0.0646 0.0403 0.0254 0.0457 0.0378 0.0123 0.0233 0.0104 0.0088 0.0034
3066.6213 1879.3603 1171.2736 738.5866 1545.0732 1279.6610 416.6620 789.9341 350.6071 299.3171 116.3349
35.6584 21.8530 13.6195 8.5882 15.4507 12.7966 4.1666 7.8993 3.5061 2.9932 1.1633
78.00
0.0000
0.0000
0.6325
0.0081
C 7 H8
92.00 70.00 84.00 84.00 98.00 98.00 100.00 18.00 94.00 36.50
0.0000 0.0080 0.0252 0.0663 0.0027 0.0733 0.0072 0.0000 1.00E-06 2.30E-05
0.0000 0.0087 0.0228 0.0601 0.0021 0.0569 0.0055 0.0000 0.0000 0.0000
0.7192 206.8498 649.1867 1707.1082 69.9999 1886.2642 185.7398 0.0000 2.57E-02 5.92E-01
0.0078 2.9550 7.7284 20.3227 0.7143 19.2476 1.8574 0.0000 2.74E-04 1.62E-02
1.00
1.0000
25732.69
338.32
Components
CP MCP CH ECP MCH 2,2,3 TMB H2O C2Cl4 HCL Total
59
Chapter 5
Material Balance
Stream 10 Molecular Mass
Mass Fraction
Mole Fraction
Mass Flow Rate
Molar Flow Rate
H2
2.00
0.0013
0.0479
32.3827
16.1914
C1
16.00
0.0057
0.0272
147.1509
9.1969
C2
30.00
0.0069
0.0176
178.3647
5.9455
C3
44.00
0.0060
0.0104
155.3259
3.5301
n C4
58.00
0.0041
0.0054
106.5960
1.8379
nC5
72.00
0.0079
0.0083
202.8658
2.8176
nC6
86.00
0.0029
0.0026
74.6026
0.8675
n C7
100.00
0.0004
0.0003
9.2875
0.0929
i-C4
58.00
0.0251
0.0330
647.1486
11.1577
iC5
72.00 86.00 86.00 86.00 86.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 78.00
0.2637
6784.4979
92.00 70.00 84.00 84.00 98.00 98.00 100.00 18.00 94.00 36.50
0.0000 0.0080 0.0252 0.0663 0.0027 0.0733 0.0077 1.00E-06 2.30E-05
0.2787 0.1144 0.0691 0.0531 0.0286 0.0460 0.0388 0.0132 0.0247 0.0108 0.0094 0.0037 0.0000 0.0000 0.0087 0.0229 0.0601 0.0021 0.0569 0.0059 0.0000 0.0000 0.0000
0.0026 206.8608 649.2215 1707.1996 70.0037 1886.3652 198.7522 0.0000 0.0257 0.5918
94.2291 38.6965 23.3723 17.9576 9.6730 15.5630 13.1316 4.4640 8.3641 3.6549 3.1791 1.2563 0.0000 0.0000 2.9552 7.7288 20.3238 0.7143 19.2486 1.9875 0.0000 0.0003 0.0162
1.00
1.0000
25732.69
338.14
Components
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6 H6 C7 H8 CP MCP CH ECP MCH 2,2,3 TMB H2O C2Cl4 HCL Total
0.1293 0.0781 0.0600 0.0323 0.0605 0.0510 0.0173 0.0325 0.0142 0.0124 0.0049 0.0000
0.0000
3327.8947 2010.0155 1544.3494 831.8794 1556.3009 1313.1645 446.4043 836.4138 365.4858 317.9081 125.6286 0.0019
Hydrogen to Hydrocarbon Ratio at the outlet of R-102 Should be 0.05 H2 : HC Ratio 0.05
60
Chapter 5
5.4
Material Balance
Material Balance around Stabilizer T 101:
61
Chapter 5
Material Balance
Stream 11 Molecular Mass
Mass Fraction
Mole Fraction Fraction
Mass Flow Rate
Molar Flow Rate
H2
2.00
0.0013
0.0479
32.3835
C1
16.1917
16.00
0.0057
0.0272
147.1544
9.1971
C2
30.00
0.0069
0.0176
178.3689
5.9456
C3
44.00
0.0060
0.0104
155.3296
3.5302
n C4
58.00
0.0041
0.0054
106.5985
1.8379
nC5
72.00
0.0079
0.0083
202.8706
2.8176
nC6
86.00
0.0029
0.0026
74.6044
0.8675
n C7
100.00
0.0004
0.0003
9.2877
0.0929
i-C4
58.00
0.0251
0.0330
647.1641
11.1580
iC5
72.00
0.2637
6784.6607
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6H6
86.00 86.00 86.00 86.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 78.00
0.1293 0.0781 0.0600 0.0323 0.0605 0.0510 0.0173 0.0325 0.0142 0.0124 0.0049 0.0000
0.2787 0.1144 0.0691 0.0531 0.0286 0.0460 0.0388 0.0132 0.0247 0.0108 0.0094 0.0037
94.2314 38.6974 23.3728 17.9580 9.6732 15.5634 13.1320 4.4641 8.3643 3.6549 3.1792 1.2563
C7 H8 CP MCP CH ECP MCH 2,2,3 TMB H2O C2Cl4 HCL
92.00 70.00 84.00 84.00 98.00 98.00 100.00 18.00 94.00 36.50
0.0000 0.0080 0.0252 0.0663 0.0027 0.0733 0.0077 0.0000 1.000E-06 2.300E-05 1.00
Components
Total
62
0.0000 0.0000 0.0087 0.0229 0.0601 0.0021 0.0569 0.0059 0.0000 8.096E-07 4.795E-05 1.0000
3327.9746 2010.0637 1544.3865 831.8994 1556.3382 1313.1960 446.4150 836.4339 365.4946 317.9158 125.6316 0.0019 0.0026 206.8658 649.2371 1707.2405 70.0053 1886.4105 198.7570 0.0000 2.573E-02 5.919E-01 25733.31
0.0000 0.0000 2.9552 7.7290 20.3243 0.7143 19.2491 1.9876 0.0000 2.738E-04 1.622E-02 338.15
Chapter 5
Material Balance
Stream 13
Molecular Mass
Mass Fraction
Mole Fraction
Mass Flow Rate
Molar Flow Rate
H2
2.00
0.0245
0.3332
32.6412
16.3206
C1
16.00
0.1105
0.1881
147.4076
9.2130
C2
30.00
0.1344
0.1221
179.3766
5.9792
C3
44.00
0.1191
0.0738
159.0084
3.6138
n C4
58.00
0.0779
0.0366
103.9217
1.7918
i-C4 iC5
58.00 72.00
0.4828 0.0508
644.3509
C2Cl4 HCL
94.00 36.50
1.000E-06 2.300E-05 1.00
0.2268 0.0192 8.970E-07 5.313E-05 1.00
2.440E-02 5.611E-01 1335.12
11.1095 0.9420 2.595E-04 1.537E-02 48.99
Molecular Mass
Mass Fraction
Mole Fraction
Mass Flow Rate
Molar Flow Rate
n C4 nC5
58.00 72.00
0.0001 0.0083
0.0001
0.0366
0.0097
2.1210 202.7881
nC6
86.00
0.0031
0.0030
74.6027
0.8675
n C7
100.00
0.0004
0.0003
9.2875
0.0929
iC5
72.00 86.00 86.00 86.00 86.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 78.00 92.00 70.00 84.00 84.00 98.00 98.00 100.00 18.00
0.2752 0.1364 0.0824 0.0633 0.0341 0.0638 0.0538 0.0183 0.0343 0.0150 0.0130 0.0051 0.0000 0.0000 0.0085 0.0266 0.0700 0.0029 0.0773 0.0081 0.000E+00 1.00
0.3223 0.1337 0.0808 0.0621 0.0334 0.0538 0.0454 0.0154 0.0289 0.0126 0.0110 0.0043 0.0000 0.0000 0.0102 0.0267 0.0702 0.0025 0.0665 0.0069 0.0000 1.00
6714.8678 3327.8996 2010.0184 1544.3517 831.8807 1556.3032 1313.1664 446.4049 836.4150 365.4864 317.9086 125.6288 0.0019 0.0026 206.8611 649.2224 1707.2021 70.0038 1886.3680 198.7525 0.0000 24397.55
93.2621 38.6965 23.3723 17.9576 9.6730 15.5630 13.1317 4.4640 8.3642 3.6549 3.1791 1.2563 0.0000 0.0000 2.9552 7.7288 20.3238 0.7143 19.2487 1.9875 0.0000 289.35
Components
Total
67.8235
Stream 14 Components
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6H6 C 7 H8 CP MCP CH ECP MCH 2,2,3 TMB H2O Total
63
2.8165
Chapter 5
5.5
Material Balance
MATERIAL BALANCE AROUND SCRUBBER: Material Balance Around Scrubber T-102
/ hr 48.75 kmole /hr
Stream 16
0.59 0.02
Stream 13
kg / hr kmole/hr
1334.53 48.75
kg / hr kmole/hr
64
Chapter 5
Material Balance
Stream 13 Molecular Mass
Mass Fraction
Mole Fraction
Mass Flow Rate
Molar Flow Rate
H2
2.00
0.0245
0.3332
32.6412
16.3206
C1
16.00
0.1105
0.1881
147.4076
9.2130
C2
30.00
0.1344
0.1221
179.3766
5.9792
C3
44.00
0.1191
0.0738
159.0084
3.6138
n C4
58.00
0.0779
0.0366
103.9217
1.7918
i-C4
58.00
0.4828
0.2268
644.3509
11.1095
iC5 C2Cl4 HCL
72.00 94.00 36.50
0.0508 1.000E-06 2.300E-05 1.00
0.0192 8.970E-07 5.313E-05
67.8235 2.440E-02 5.611E-01 1335.12
0.9420 2.595E-04 1.537E-02
Molecular Mass
Mass Fraction
Mole Fraction
Mass Flow Rate
Molar Flow Rate
H2
2.00
0.0245
0.3332
32.6412
16.3206
C1
16.00
0.1105
0.1881
147.4076
9.2130
C2
30.00
0.1344
0.1221
179.3766
5.9792
C3
44.00
0.1191
0.0738
159.0084
3.6138
n C4
58.00
0.0779
0.0366
103.9217
1.7918
i-C4
58.00
0.4828
0.2268
644.3509
11.1095
iC5 C2Cl4 HCL NaCl
72.00 94.00 36.50 40.00
0.0508 0.0000 0.0000 2.400E-05 1.00
0.0192 0.0000 0.0000 5.403E-05 1.00
67.8235 0.0000 0.0000 5.855E-01 1335.12
0.9420 0.0000 0.0000 1.563E-02 48.99
Components
Total
1.00
48.99
Stream 15 Components
Total
65
CHAPTER 6
ENERGY BALANCE
Chapter 6
Energy Balance
CHAPTER # 6 ENERGY BALANCE
The First Law of Thermodynamics is a statement of energy conservation. Although energy cannot be created or destroyed, it can be converted from one form to another (for example, internal energy stored in molecular bonds can be converted into kinetic energy; potential energy can be converted to kinetic or to internal energy, etc.). Energy can also be transferred from one point to another, or from one body to a second body. Energy transfer can occur by flow of heat, by transport of mass (transport of mass is otherwise known as convection), or by performance of work. The general energy balance for a process can be expressed in words as: Accumulation of Energy in System = Input of Energy into System – Output of Energy from System 6.1
ENERGY BALANCE AROUND REACTOR R-101:
66
Chapter 6
6.1.1
Energy Balance
Molar Composition
Components
STREAM IN Mol%
STREAM OUT Mol%
H2
18.3713
4.8240
C1
2.3317
2.7232
C2
1.5074
1.7673
C3
0.8950
1.0682
n C4
3.1064
1.8014
nC5
14.7758
4.1623
nC6
11.7082
3.2049
n C7
5.8868
0.5490
i-C4
0.1884
2.0228
iC5
9.5079
24.5136
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP
5.5287
10.5400
3.5504
6.4593
0.4091
4.0257
0.8896
2.5385
2.3622
4.5669
2.3616
3.7824
0.1734
1.2316
0.7078
2.3349
0.3592
1.0363
0.1114
0.8847
0.1772
0.3439
C6H6
2.0560
0.0024
C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4
1.9822
0.0023
1.0703
0.8734
3.0147
2.2844
2.9196
6.0070
0.1811
0.2111
3.8666
5.6892
0.0000
0.5490
0.0000
0.0000
0.0000
0.0001
0.00E+00
4.79E-03
HCL
67
Chapter 6
Energy Balance
6.1. 2 Heat of Formation
∆Hf° Reactants
Components
∆Hf°Products Heat of formation at 25 C
ni
∆Hf°
ni∆Hf°
ni
∆Hf°
ni∆Hf°
kmol/hr
kJ/kmole
kJ/hr
kmol/hr
kJ/kmole
kJ/hr
H2
72.49
0
0.00
16.32
0
0.00
C1
9.20
-74900
-689130.06
9.21
-74900
-690056.81
C2
5.95
-84738
-504013.73
5.98
-84738
-506670.71
C3
3.53
-103890
-366894.77
3.61
-103890
-375443.21
n C4
12.26
-126190
-1546760.31
6.09
-126190
-769057.96
nC5
58.30
-146490
-8540779.57
14.08
-146490
-2062855.48
nC6
46.20
-167290
-7728550.98
10.84
-167290
-1813915.64
n C7
23.23
-187890
-4364338.62
1.86
-187890
-348990.26
i-C4
0.74
-134590
-100066.10
6.84
-134590
-921061.70
iC5
37.52
-154590
-5799653.70
82.93
-154590
-12820832.96
2 MP
21.82
-174390
-3804360.11
35.66
-174390
-6218533.77
3 MP
14.01
-171690
-2405262.73
21.85
-171690
-3751986.83
2,2 DMB
1.61
-185690
-299724.59
13.62
-185690
-2529025.09
2,3DMB
3.51
-177890
-624452.89
8.59
-177890
-1527774.43
2 MH
9.32
-195090
-1818390.34
15.45
-195090
-3014315.96
3 MH
9.32
-192390
-1792743.05
12.80
-192390
-2461966.49
2,2 DMP
0.68
-206290
-141167.13
4.17
-206290
-859541.38
2,3 DMP
2.79
-199390
-556852.69
7.90
-199390
-1575066.62
2,4 DMP
1.42
-202090
-286391.89
3.51
-202090
-708549.55
3,3 DMP
0.44
-201690
-88633.00
2.99
-201690
-603699.30
3 EP
0.70
-189790
-132724.11
1.16
-189790
-220794.33
C6H6
8.11
82977
673167.24
0.01
82977
672.86
C7H8
7.82
50029
391303.01
0.01
50029
391.13
CP
4.22
-77288
-326415.54
2.96
-77288
-228388.25
MCP
11.90
-106790
-1270303.26
7.73
-106790
-825326.23
CH
11.52
-123190
-1419169.36
20.32
-123190
-2503582.59
ECP
0.71
-127190
-90891.70
0.71
-127190
-90850.88
MCH
15.26
-154890
-2363156.82
19.25
-154890
-2981292.20
223TMB
0.00
-204890
0.00
1.86
-204890
-380566.37
H2O
0.00
-241814
-0.19
0.00
-241814
0.00
C2Cl4
0.00
-100488
0.00
0.00
-100488
-27.51
HCL NaOH
0.00
-100488
0
0.02
-100488
-1629.40
0.00
0
0.00
0.00
TOTAL
394.58
-45996357
338.34
-50790738
68
Chapter 6
6.1.3
Energy Balance
For reactants Cp of Gas at 25° C to 170° C Components
H2 C1 C2 C3 n C4 nC5 nC6 n C7 i-C4 iC5 2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6H6 C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH TOTAL
n
x
i
i
∫CpGdT
xii∫CpGdT
kmole/hr
Mol%
kJ/kmole
kJ/kmole
72.4 9 9.2 0 5.9 5 3.5 3 12.2 6 58.3 0 46.2 0 23.2 3 0.7 4 37.5 2 21.8
18.37
4214.10
774.1861
2.3 3 1.5 1 0.9 0 3.1 1 14.78
5746.43
133.9922
9020.95
135.9811
12889.61
115.3638
16918.74
525.5668
20860.70
3082.3384
11.71
24834.86
2907.7137
5.8 9 0.1 9 9.5 1 5.5
28805.94
1695.7378
16967.58
31.9710
20771.74
1974.9472
25105.30
1387.9933
2 14.0 11.6
3 3.5 5 0.4
24821.51
881.2673
24901.95
101.8659
1 3.5 1 9.3
1 0.8 9 2.3
24640.13
219.2063
29441.95
695.4734
2 9.3 2 0.6
6 2.3 6 0.1
28781.12
679.6809
29355.81
50.9110
8 2.7 9 1.4
7 0.7 1 0.3
-4163.13
-29.4658
28781.12
103.3678
2 0.4 4 0.7
6 0.1 1 0.1
28781.12
32.0539
28781.12
51.0089
0 8.1 1 7.8
8 2.0 6 1.9
15030.04
309.0205
18801.43
372.6870
2 4.2 2 11.9
8 1.0 7 3.0
15761.36
168.6997
20285.01
611.5245
0 11.5 20.7
1 2.9 2 0.1
19945.76
582.3328
24921.30
45.1340
1 15.2 60.0
8 3.8 7 0.0
24238.46
937.2080
0 0.0 0 0.0
28927.16 0.0 0 0.0
0.0000
0 0.0 0 0.0 0 0.0 0 0.0 0 394.58
0 0.0 0 0.0 010 0
69
00 0
0.0000 0.0000 0.0000 0.0000 18577.77
Chapter 6
6.1.4
Energy Balance
For products Cp of gas at 25°C to 175°C ni
xi
∫CpGdT
xii∫CpGdT
kmole/hr
Mol%
kJ/kmole
kJ/kmole
H2
16.32
4.82
4360.15
210.336
C1
9.21
2.72
5965.68
162.456
C2
5.98
1.77
9379.74
165.772
C3
Components
3.61
1.07
13407.51
143.216
n C4
6.09
1.80
17592.94
316.917
nC5
14.08
4.16
21695.55
903.033
nC6
10.84
3.20
25828.32
827.781
n C7
1.86
0.55
29957.92
164.473
i-C4
6.84
2.02
17647.22
356.964
iC5
82.93 35.66 21.85 13.62 8.59 15.45 12.80 4.17 7.90 3.51 2.99 1.16
24.51 10.54 6.46 4.03 2.54 4.57 3.78 1.23 2.33 1.04 0.88 0.34
21607.06 26111.09 25814.45 25905.34 25632.22 30627.01 29932.92 30545.77 -4377.30 29932.92 29932.92 29932.92
5296.669 2752.097 1667.445 1042.861 650.678 1398.720 1132.194 376.194 -102.206 310.204 264.824 102.929
0.01 0.01 2.96 7.73 20.32 0.71 19.25 1.86 0.00 0.00 0.02
0.00 0.00 0.87 2.28 6.01 0.21 5.69 0.55 0.00 0.00 0.00
15649.22 19568.49 16429.78 21129.78 20790.13 25959.49 25243.14 30093.11 0.00 0.00 0
0.375 0.452 143.505 482.683 1248.866 54.808 1436.140 165.215 0.000 0.000 0.000
0.00 338.34
0.00 100
0
0.000 21675.600
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6H6 C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH TOTAL
70
Chapter 6
6.1.5
Energy Balance
Heat of reaction
∆Hrxn
=
∆Hprd
-
∆Hrea
∆Hprd
=
ni∆Hf°
+
nT CpGdT
∆Hprd
=
-50790738
+
∆Hprd
=
-43457097 kJ/hr
∫
now,
now, ni∆Hf°
∫
∆Hrea
=
∆Hrea
=
-45996357
+
∆Hrea
=
-38665890
kJ/hr
∆Hrxn
=
∆Hprd
-
∆Hrea
∆Hrxn
=
-43457097
-
-38665890
∆Hrxn
=
-4791208
kJ/hr
∆Hrxn
=
-5.E+06
kJ/hr
nT CpGdT
+
7330467.333
SO,
6.1.6
For cooling coils Components Water
ni kmole/hr 2900.00
xi
∫CpLdT
Mol% 100.00
kJ/kmole K 1510.00
Total
n∫CpLdT kJ/hr 4379000 4379000
Heat Gained By Cooling Water 4.379E+06 kJ/hr
71
= Heat generated by Reactions =
-4.791E+06 kJ/hr
Chapter 6
6.2
Energy Balance
ENERGY BALANCE AROUND REACTOR R-102:
72
Chapter 6
6.2.1
Energy Balance
Molar Composition
Components
STREAM IN Mol%
STREAM OUT Mol%
H2
4.8240
4.7884
C1
2.7232
2.7199
C2
1.7673
1.7583
C3
1.0682
1.0440
n C4
1.8014
0.5435
nC5
4.1623
0.8333
nC6
3.2049
0.2565
n C7
0.5490
0.0275
i-C4
2.0228
3.2998
iC5
24.5136
27.8671
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP
10.5400
11.4440
6.4593
6.9121
4.0257
5.3107
2.5385
2.8607
4.5669
4.6026
3.7824
3.8835
1.2316
1.3202
2.3349
2.4736
1.0363
1.0809
0.8847
0.9402
0.3439
0.3715
C6H6
0.0024
0.0000
C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH
0.0023
0.0000
0.8734
0.8740
2.2844
2.2857
6.0070
6.0105
0.2111
0.2113
5.6892
5.6925
0.5490
0.5878
0.0000
0.0000
0.0001
0.0001
0.0048
0.0048
0.0000
0.0000
73
Chapter 6
6.2.2
Energy Balance
Heat of Reaction
∆Hf° Reactants
Components
∆Hf°Products o
ni kmole/hr
∆Hf°
Heat of formation at 25 C ni∆Hf°
ni
∆Hf°
ni∆Hf°
kJ/kmole
kJ/hr
kmole/hr
kJ/kmole
kJ/hr
H2
16.32
0
0.00
16.20
0
0.00
C1
9.21
-74900
-690056.81
9.20
-74900
-689222.26
C2
5.98
-84738
-506670.71
5.95
-84738
-504081.16
C3
3.61
-103890
-375443.21
3.53
-103890
-366943.86
n C4
6.09
-126190
-769057.96
1.84
-126190
-232045.09
nC5
14.08
-146490
-2062855.48
2.82
-146490
-412970.40
nC6
10.84
-167290
-1813915.64
0.87
-167290
-145197.88
n C7
1.86
-187890
-348990.26
0.09
-187890
-17459.69
i-C4
6.84
-134590
-921061.70
11.16
-134590
-1502531.13
iC5
82.93 35.66 21.85 13.62 8.59 15.45 12.80 4.17 7.90 3.51 2.99 1.16
-154590 -174390 -171690 -185690 -177890 -195090 -192390 -206290 -199390 -202090 -201690 -189790
-12820832.96 -6218533.77 -3751986.83 -2529025.09 -1527774.43 -3014315.96 -2461966.49 -859541.38 -1575066.62 -708549.55 -603699.30 -220794.33
94.28 38.72 23.38 17.97 9.68 15.57 13.14 4.47 8.37 3.66 3.18 1.26
-154590 -174390 -171690 -185690 -177890 -195090 -192390 -206290 -199390 -202090 -201690 -189790
-14574755.94 -6751921.51 -4014954.53 -3336340.09 -1721663.04 -3037828.49 -2527762.64 -921385.12 -1668626.89 -739009.55 -641535.51 -238559.35
0.01
82977
672.86
2.04
50029 -77288 -106790 -123190 -127190 -154890 -204890 -241814 -100488 0
391.13 -228388.25 -825326.23 -2503582.59 -90850.88 -2981292.20 -380566.37 0.00 -27.51 0
0.00 0.00 2.96 7.73 20.33 0.71 19.26 1.99 0.00 0.00 0.02
82977
0.01 2.96 7.73 20.32 0.71 19.25 1.86 0.00 0.000273748 0.016214908
50029 -77288 -106790 -123190 -127190 -154890 -204890 -241814 -100488 0
1.40 -228521.45 -825807.58 -2505042.75 -90903.86 -2983030.96 -407443.50 0.00 -27.52 0.00
0 338.34
0
0 -50789109
0.00 338.34
0
0.00 -51085568
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6H6 C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH NaOOOH TOTAL
74
Chapter 6
6.2.3
Energy Balance
For Reactants Cp of Gas 25oC to 120oC ni
xi
∫CpGdT
xii∫CpGdT
kmolw/hr
Mol%
kJ/kmole
kJ/kmole
H2
16.32
4.82
2755.90
132.95
C1
9.21
2.72
3631.20
98.88
C2
5.98
1.77
5602.91
99.02
C3
3.61
1.07
7969.39
85.13
n C4
6.09
1.80
10499.69
189.14
nC5
14.08
4.16
12918.82
537.72
nC6
10.84
3.20
15382.42
493.00
n C7
1.86
0.55
17844.04
97.97
i-C4
6.84
2.02
10504.74
212.49
iC5
82.93 35.66 21.85 13.62 8.59 15.45 12.80 4.17 7.90 3.51 2.99 1.16
24.51 10.54 6.46 4.03 2.54 4.57 3.78 1.23 2.33 1.04 0.88 0.34
12837.25 15538.33 15374.77 15375.37 15219.10 18178.23 17822.99 18070.27 -2304.75 17822.99 17822.99 17822.99
3146.87 1637.73 993.11 618.96 386.34 830.19 674.14 222.55 -53.81 184.70 157.68 61.29
0.01 0.01 2.96 7.73 20.32 0.71 19.25 1.86 0.00 0.00 0.02 0.00 338.34
0.00 0.00 0.87 2.28 6.01 0.21 5.69 0.55 0.00 0.00 0.00 0.00 100
9189.32 11547.23 9515.48 12346.59 12055.61 15166.19 14782.92 17857.25 0.00 0.00 0.00 0.00 369150.25
0.22 0.27 83.11 282.04 724.18 32.02 841.03 98.04 0.00 0.00 0.00 0.00 12866.97
Components
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6H6 C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH TOTAL
75
Chapter 6
6.2.4
Energy Balance
For Products Cp of Gas 25oC to 123oC ni
xi
∫CpGdT
xii∫CpGdT
kmolw/hr
Mol%
kJ/kmole
kJ/kmole
H2
16.20
4.79
2843.26
136.147
C1
9.20
2.72
3754.15
102.108
C2
5.95
1.76
5799.15
101.967
C3
3.53
1.04
8251.04
86.140
n C4
1.84
0.54
10867.99
59.070
nC5
2.82
0.83
13374.02
111.441
nC6
0.87
0.26
15924.28
40.853
n C7
0.09
0.03
18472.49
5.074
i-C4
11.16
3.30
10875.05
358.851
iC5
94.28 38.72 23.38 17.97 9.68 15.57 13.14 4.47 8.37 3.66 3.18 1.26
27.87 11.44 6.91 5.31 2.86 4.60 3.88 1.32 2.47 1.08 0.94 0.37
13291.37 16086.56 15916.28 15920.31 15758.11 18822.99 18451.11 18714.89 -2402.39 18451.11 18451.11 18451.11
3703.923 1840.947 1100.144 845.485 450.789 866.342 716.553 247.072 -59.425 199.434 173.473 68.552
0.00 0.00 2.96 7.73 20.33 0.71 19.26 1.99 0.00 0.00 0.02
0.00 0.00 0.87 2.29 6.01 0.21 5.69 0.59 0.00 0.00 0.00
9521.25 11960.61 9867.22 12796.14 12500.07 15718.56 15319.17 18490.44 0.00 0.00 0.00
0.001 0.001 86.235 292.482 751.319 33.206 872.051 108.684 0.000 0.000 0.000
0.00 338.34
0.00 100
0.00
Components
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6H6 C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH TOTAL
76
0.000 13298.917
Chapter 6
6.2.5
Energy Balance
Heat of reaction
∆Hrxn
=
∆Hprd
-
∆Hrea
∆Hprd
=
ni∆Hf°
+
nT∫CpGdT
∆Hprd
=
-51085568
+
4499509.04
∆Hprd
=
-46586059.29
∆Hrea
=
ni∆Hf°
+
nT CpGdT
∆Hrea
=
-50789109
+
4353361.694
∆Hrea
=
-46435747
now,
kJ/hr
now,
so,
6.2.6
∫
kJ/hr
∆Hrxn
=
∆Hprd
-
∆Hrxn
=
-46586059
-
∆Hrxn
=
-2.E+05
∆Hrea -46435747
kJ/hr
For cooling coils Components Water
ni
xi
kmole/hr 95.00
Mol% 100.00
∫CpGdT kJ/kmole K 1510.00
Total
n∫CpLdT kJ/hr 143450 143450
Heat Gained By Cooling Water
1.435E+05 kJ/hr
77
=
Heat generated by Reaction
=
-1.503E+05 kJ/hr
Chapter 6
6.3
Energy Balance
ENERGY BALANCE AROUND HEAT EXCHANGER E 101:
E-101
TUBE SIDE
SHELL SIDE
0
Temperature ( C) Inlet Temperature
36.84
Outlet Temperature Boiling Point
70
93.63
5.901
44.5039
2400
2200
2370
2100
0.205
0.0917
Pressure (kPa) Inlet Pressure Outlet Pressure Average Pressure vapor Fraction in vapor Fraction out vapor Fraction avg
123
0.249
0.0678
0.227
0.07975
78945.18
87741.00
Constant Heat of Vaporization (kJ/kmole)
78
Chapter 6
Energy Balance
6.3.1 Molar Composition:
Stream No.3
Stream No.4
Stream No.10
Stream No.11
Mol%
Mol%
Mol%
Mol%
H2
18.3713
18.3713
4.7884
4.7884
C1
2.3317
2.3317
2.7199
2.7199
C2
1.5074
1.5074
1.7583
1.7583
C3
0.8950
0.8950
1.0440
1.0440
n C4
3.1064
3.1064
0.5435
0.5435
nC5
14.7758
14.7758
0.8333
0.8333
nC6
11.7082
11.7082
0.2565
0.2565
n C7
5.8868
5.8868
0.0275
0.0275
i-C4
0.1884
0.1884
3.2998
3.2998
iC5
9.5079 5.5287 3.5504 0.4091 0.8896 2.3622 2.3616 0.1734 0.7078 0.3592 0.1114 0.1772
9.5079 5.5287 3.5504 0.4091 0.8896 2.3622 2.3616 0.1734 0.7078 0.3592 0.1114 0.1772
27.8671 11.4440 6.9121 5.3107 2.8607 4.6026 3.8835 1.3202 2.4736 1.0809 0.9402 0.3715
27.8671 11.4440 6.9121 5.3107 2.8607 4.6026 3.8835 1.3202 2.4736 1.0809 0.9402 0.3715
2.0560 1.9822 1.0703 3.0147 2.9196 0.1811 3.8666 0.0000 0.0000 0.0000 0.0000 0.0000
2.0560 1.9822 1.0703 3.0147 2.9196 0.1811 3.8666 0.0000 0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.8740 2.2857 6.0105 0.2113 5.6925 0.5878 0.0000 0.0001 0.0048 0.0000
0.0000 0.0000 0.8740 2.2857 6.0105 0.2113 5.6925 0.5878 0.0000 0.0001 0.0048 0.0000
100
100
100
100
Components
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6H6 C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH Total
79
Chapter 6
Energy Balance
6.3.2 Tube Side
ni
xi
∫CpLdT
xii∫CpLdT
Mol%
liquid Fraction
kJ/kmole K
kJ/kmole K
H2
72.49
18.37
0.0170
163840.79
2784.06634
C1
9.20
2.33
0.0077
127630.87
988.271101
C2
5.95
1.51
0.0111
7264.71
80.3047805
C3
3.53
0.90
0.0090
4742.84
42.4946293
n C4
12.26
3.11
0.0360
5055.50
182.108916
nC5
58.30
14.78
0.1810
nC6
46.20
11.71
0.1469
6853.99
1006.81056
n C7
23.23
5.89
0.0745
7784.82
579.918369
i-C4
0.74
0.19
0.0021
5168.13
10.9664692
iC5
37.52
9.51
0.1160
5884.95
682.360958
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6H6 C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH
21.82
5.53
0.0691
6811.58
470.452231
14.01
3.55
0.0444
6688.65
297.186824
1.61
0.41
0.0051
6649.77
33.8243427
3.51
0.89
0.0111
6642.84
73.7434272
9.32
2.36
0.0298
7826.38
233.617288
9.32
2.36
0.0299
7701.81
230.101309
0.68
0.17
0.0022
7802.27
17.0513012
2.79
0.71
0.0089
7631.96
68.2607597
1.42
0.36
0.0045
7904.69
35.7737834
0.44
0.11
0.0014
7552.68
10.6206163
0.70 8.11
0.18 2.06
7689.52 4748.36
17.2390551 122.37503
7.82
1.98
0.0022 0.0258 0.0251
5456.22
137.127268
4.22
1.07
0.0133
4556.56
60.4014987
11.90
3.01
0.0379
5625.98
213.162185
11.52
2.92
0.0368
5477.83
201.410753
0.71
0.18
0.0023
6587.94
15.1176227
15.26
3.87
0.0490
6545.43
320.449969
0.00
0.00
0.0000
7490.68
0
0.00
0.00
0.0000
2496.55
0
0.00
0.00
0.0000
-5566.74
0
0.00
0.00
0.0004
0.0000
0
0.00
0.00
0.0000
0.0000
0
Components
TOTAL
kmole/hr
394.58
100.00
80
1.00
5890
464434.24
1065.39389
7715.01
Chapter 6
Energy Balance
Components
ni kmole/hr
H2 C1 C2 C3 n C4 nC5 nC6 n C7
72.49 9.20 5.95 3.53 12.26 58.30 46.20 23.23
xi
∫CpGdT
xii∫CpGdT
Mol%
Vapor Fraction
kJ/kmole K
kJ/kmole K
18.37
0.7923
960.45
760.9602
2.33
0.0801
1231.83
98.6947
1.51
0.0297
1871.97
55.5301
0.90
0.0088
2651.24
23.4494
3.11
0.0130
3505.53
45.4545
14.78
0.0254
4303.76
109.3437
11.71
0.0083
5125.09
42.3745
5.89
0.0018
5945.75
10.8981
i-C4
0.74
0.19
0.0010
3498.95
3.4979
iC5
37.52
9.51
0.0200
4268.77
85.4095
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP
21.82
5.53
0.0050
5172.99
25.8335
14.01
3.55
0.0029
5122.97
14.9625
1.61
0.41
0.0005
5108.03
2.3304
3.51
0.89
0.0008
5057.87
4.2946
9.32
2.36
0.0009
6035.99
5.3863
9.32
2.36
0.0009
5936.93
5.0777
0.68
0.17
0.0001
5984.00
0.5420
2.79
0.71
0.0003
-700.73
-0.1885
1.42
0.36
0.0002
5936.93
1.0988
0.44
0.11
0.0000
5936.93
0.2739
0.70
0.18
0.0001
5936.93
0.3638
C6H6
8.11
2.06
0.0013
3025.39
4.0382
C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH
7.82
1.98
0.0005
3818.32
1.8633
4.22
1.07
0.0014
3098.21
4.3221
11.90
3.01
0.0020
4049.71
8.0060
11.52
2.92
0.0016
3930.95
6.2002
0.71
0.18
0.0000
4973.82
0.2319
15.26
3.87
0.0012
4857.50
5.6009
0.00
0.00
0.0000
5931.16
0.0000
0.00
0.00
0.0000
0.00
0.0000
0.00
0.00
0.0000
0.00
0.0000
0.00
0.00
0.0000
0.00
0.0000
0.00
0.00
0.0000
0
0.0000
394.58
100.00
1.00
122577.23
300.97
TOTAL
81
Chapter 6
Energy Balance
6.3.3 Shell Side
ni
xi
∫CpLdT
xii∫CpLdT
kmole/hr
Mol%
liquid Fraction
kJ/kmole K
kJ/kmole K
H2
16.20
4.79
0.0126
-199512.06
-2514.64852
C1
9.20
2.72
0.0143
-279046.67
-3994.81536
C2
5.95
1.76
0.0136
-14568.75
-198.505567
C3
3.53
1.04
0.0095
-6659.42
-63.2080384
0.54
0.0054
-5626.65
-30.3939262
Components
n C4
1.84
nC5
2.82
0.83
0.0087
nC6
0.87
0.26
0.0028
-6894.52
-19.223717
n C7
0.09
0.03
0.0003
-7634.15
-2.48558706
i-C4
11.16
3.30
0.0324
-6170.29
-199.987136
-5.96E+03
-51.844729
iC5
94.28
27.87
0.2898
-6036.68
-1749.62666
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP
38.72
11.44
0.1221
-6805.47
-830.901233
23.38
6.91
0.0739
-6650.91
-491.458483
17.97
5.31
0.0564
-6632.83
-373.849325
9.68
2.86
0.0305
-6613.38
-201.695991
15.57
4.60
0.0498
-7801.45
-388.551913
13.14
3.88
0.0420
-7632.19
-320.811117
4.47
1.32
0.0142
-7800.55
-111.039608
8.37
2.47
0.0267
-7551.44
-201.977523
3.66
1.08
0.0116
-7890.58
-91.9132828
3.18
0.94
0.0102
-7563.20
-76.915539
1.26
0.37
0.0040
-7595.10
-30.4626677
C6H6
0.00
0.00
0.0000
-4675.81
0
C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH
0.00
0.00
0.0000
-5385.02
0
2.96
0.87
0.0092
-4701.57
-43.2365038
TOTAL
7.73
2.29
0.0246
-5691.74
-139.988369
20.33
6.01
0.0648
-5623.11
-364.213341
0.71
0.21
0.0023
-6637.69
-15.1551398
19.26 1.99
5.69 0.59
0.0618 0.0064
-6628.75 -7355.24
-409.653369 -46.8487831
0.00
0.00
0.0000
-2241.28
0
0.00
0.00
0.0000
-5566.74
0
0.02
0.00
0.0004
0.0000
0
0.00
0.00
0.0000
0.0000
0
338.33
100.00
1.00
-673158.11
-11929.58
82
Chapter 6
Energy Balance
Components
ni kmole/hr
Vapor Fraction
∫CpGdT
xii∫CpGdT
Mol%
xi
kJ/kmole K
kJ/kmole K
H2
16.20
4.79
0.3974
-768.02
-305.229
C1
9.20
2.72
0.1548
-1060.10
-164.112
C2
5.95
1.76
0.0570
-1676.96
-95.562
1.04
0.0194
-2401.60
-46.630
0.54
0.0054
-3146.11
-16.970
C3 n C4
3.53 1.84
nC5
2.82
0.83
0.0044
-3884.61
-17.250
nC6
0.87
0.26
0.0007
-4624.54
-3.431
n C7
0.09
0.03
0.0000
-5363.89
-0.254
i-C4
11.16
3.30
0.0389
-3159.54
-122.906
iC5
94.28
27.87
0.1691
-3871.29
-654.638
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP
38.72
11.44
0.0385
-4677.25
-180.028
23.38
6.91
0.0218
-4621.61
-100.737
17.97
5.31
0.0209
-4643.51
-97.089
9.68
2.86
0.0099
-4593.80
-45.345
15.57
4.60
0.0084
-5494.82
-46.326
13.14
3.88
0.0069
-5360.15
-36.822
4.47
1.32
0.0030
-5485.32
-16.370
8.37
2.47
0.0045
788.53
3.541
3.66
1.08
0.0024
-5360.15
-12.992
3.18
0.94
0.0018
-5360.15
-9.652
1.26
0.37
0.0006
-5360.15
-3.382
-2814.73
0.000
C6H6
0.00
0.00
0.0000
C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH
0.00
0.00
0.0000
-3513.06
0.000
2.96
0.87
0.0038
-2964.10
-11.284
7.73
2.29
0.0062
-3803.45
-23.468
20.33
6.01
0.0140
-3747.10
-52.430
0.71
0.21
0.0003
-4673.08
-1.360
19.26
5.69
0.0085
-4541.58
-38.697
1.99
0.59
0.0013
-5395.11
-6.827
0.00
0.00
0.0000
0.00
0.000
0.00
0.00
0.0000
0.00
0.000
0.02
0.00
0.0000
0
0.000
0.00
0.00
0.0000
0
0.000
TOTAL
338.33
1.00
83
-167.974
Chapter 6
Energy Balance
6.3.4 Calculations: TUBE SIDE
Total Enthalpy = HT
Sensible Heat of Liquid + Latent Heat + Sensible Heat of Vapor HL
=
+
HV + HG
HG
=
n∫CpGdT
HG
=
HV
=
nλ
HV
=
1370608.32 kJ/hr
HL
=
n CpLdT
HL
=
3044189.64 kJ/hr
HT
=
4533553.9 kJ/hr
HT
=
4.53E+06
118755.937 kJ/hr
∫
kJ/hr
SHELL SIDE
Total Enthalpy =
Sensible Heat of Liquid + Latent Heat + Sensible Heat of Vapor
HT
=
HL
+
HV
HG
=
HG
=
-56830.9023 kJ/hr
HV
=
nλ
HV
=
-709486.596 kJ/hr
HL
=
+
HG
n∫CpGdT
n∫CpLd
HL
=
-4036164.38 kJ/hr
HT
=
-4802481.88 kJ/hr
HT
=
-4.80E+06
kJ/hr
Heat Gained By Tube Side
=
Heat Lost By Shell Side
4.534E+06
=
-4.802E+06
kJ/hr
84
kJ/hr
Chapter 6
6.4
Energy Balance
ENERGY BALANCE AROUND HEAT EXCHANGER E 102:
E-102
TUBE SIDE
SHELL SIDE
0
Temperature ( C) Inlet Temperature
70
175
Outlet Temperature Boiling Point
147
120
5.901
30.43
2370
2269
2330
2210
Pressure (kPa) Inlet Pressure Outlet Pressure Average Pressure vapor Fraction in vapor Fraction out vapor Fraction avg Boiling Point Constant Heat of Vaporization (kJ/kmole)
0.2146
0.3641
0.3489
8.61E-02
0.28175
0.2251
5.901
30.43
10589.08
85
-23473.32
Chapter 6
Energy Balance
6.4.1 Molar Composition:
Components
Stream No.3
Stream No.4
Stream No.10
Stream No.11
Mol%
Mol%
Mol%
Mol%
H2
18.3713
18.3713
4.8240
4.8240
C1
2.3317
2.3317
2.7232
2.7232
C2
1.5074
1.5074
1.7673
1.7673
C3
0.8950
0.8950
1.0682
1.0682
n C4
3.1064
3.1064
1.8014
1.8014
nC5
14.7758
14.7758
4.1623
4.1623
nC6
11.7082
11.7082
3.2049
3.2049
n C7
5.8868
5.8868
0.5490
0.5490
i-C4
0.1884
0.1884
2.0228
2.0228
iC5
9.5079 5.5287 3.5504 0.4091 0.8896 2.3622 2.3616 0.1734 0.7078 0.3592 0.1114 0.1772
9.5079 5.5287 3.5504 0.4091 0.8896 2.3622 2.3616 0.1734 0.7078 0.3592 0.1114 0.1772
24.5136 10.5400 6.4593 4.0257 2.5385 4.5669 3.7824 1.2316 2.3349 1.0363 0.8847 0.3439
24.5136 10.5400 6.4593 4.0257 2.5385 4.5669 3.7824 1.2316 2.3349 1.0363 0.8847 0.3439
2.0560 1.9822 1.0703 3.0147 2.9196 0.1811 3.8666 0.0000 0.0000 0.0000 0.0000 0.0000 100
2.0560 1.9822 1.0703 3.0147 2.9196 0.1811 3.8666 0.0000 0.0000 0.0000 0.0000 0.0000 100
0.0024 0.0023 0.8734 2.2844 6.0070 0.2111 5.6892 0.5490 0.0000 0.0001 0.0048 0.0000 100
0.0024 0.0023 0.8734 2.2844 6.0070 0.2111 5.6892 0.5490 0.0000 0.0001 0.0048 0.0000 100
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6H6 C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH Total
86
Chapter 6
Energy Balance
6.4.2 Tube Side
ni
xi
∫CpLdT
xii∫CpLdT
kmole/hr
Mol%
liquid Fraction
kJ/kmole K
kJ/kmole K
H2
72.49
18.37
0.0170
524673.28
8915.51612
C1
9.20
2.33
0.0077
758742.22
5875.091135
Components
C2
5.95
1.51
0.0111
39811.05
440.075118
C3
3.53
0.90
0.0090
17954.99
160.8721251
15009.50
540.6714188
n C4
12.26
3.11
0.0360
nC5
58.30
14.78
0.1810
nC6
46.20
11.71
0.1469
18107.01
2659.813793
1.57E+04
2835.3435
n C7
23.23
5.89
0.0745
20036.58
1492.595104
i-C4
0.74
0.19
0.0021
16529.78
35.07521004
iC5
37.52 21.82 14.01 1.61 3.51 9.32 9.32 0.68 2.79 1.42 0.44 0.70
9.51 5.53 3.55 0.41 0.89 2.36 2.36 0.17 0.71 0.36 0.11 0.18
0.1160
15866.01 17855.82 17448.62 17398.60 17347.93 20470.78 20020.43 20459.10 19805.23 20693.98 19844.47 19919.07
1839.666534 1233.239608 775.2681686 88.49878246 192.5827109 611.0525945 598.1359298 44.7119097 177.1392678 93.6535025 27.90540672 44.65634249
8.11 7.82 4.22 11.90 11.52 0.71 15.26 0.00 0.00 0.00 0.00 0.00 394.58
2.06 1.98 1.07 3.01 2.92 0.18 3.87 0.00 0.00 0.00 0.00 0.00 100.00
0.0258
12272.22 14132.02 12335.95 14925.56 14827.71 17405.47 17395.98 19272.40 5875.66 -5566.74 0.0000 0.0000 1776537.03
316.2807209 355.1701859 163.5246758 565.5136593 545.1904029 39.94105385 851.6697922 0 0 0 0 0 22638.42
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6H6 C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH TOTAL
87
0.0691 0.0444 0.0051 0.0111 0.0298 0.0299 0.0022 0.0089 0.0045 0.0014 0.0022 0.0251 0.0133 0.0379 0.0368 0.0023 0.0490 0.0000 0.0000 0.0000 0.0004 0.0000 1.00
Chapter 6
Energy Balance
Components
H2
ni kmole/hr 72.49
Vapor Fraction
∫CpGdT
xii∫CpGdT
Mol%
xi
kJ/kmole K
kJ/kmole K
18.37
0.7923
2240.16
1774.8758
C1
9.20
2.33
0.0801
3099.31
248.3173
C2
5.95
1.51
0.0297
4906.03
145.5322
C3
3.53
0.90
0.0088
7026.70
62.1490
n C4
12.26
3.11
0.0130
9204.49
119.3501
nC5
58.30
14.78
0.0254
11364.60
288.7354
nC6
46.20
11.71
0.0083
13529.06
111.8589
n C7
23.23
5.89
0.0018
15691.84
28.7620
9243.86
9.2411
11326.69 13683.03 13520.74 13586.11 13440.61 16073.41 15681.00 16047.89 -2332.94 15681.00 15681.00 15681.00
226.6241 68.3319 39.4895 6.1982 11.4123 14.3433 13.4115 1.4536 -0.6275 2.9021 0.7234 0.9608
8238.34 10281.35 8682.12 11136.05 10976.71 13682.27 13295.61 15784.86 0.00 0.00 0.00 0 326452.92
10.9963 5.0173 12.1120 22.0152 17.3133 0.6378 15.3305 0.0000 0.0000 0.0000 0.0000 0.0000 917.79
i-C4
0.74
0.19
0.0010
iC5
37.52 21.82 14.01 1.61 3.51 9.32 9.32 0.68 2.79 1.42 0.44 0.70
9.51 5.53 3.55 0.41 0.89 2.36 2.36 0.17 0.71 0.36 0.11 0.18
0.0200
8.11 7.82 4.22 11.90 11.52 0.71 15.26 0.00 0.00 0.00 0.00 0.00 394.58
2.06 1.98 1.07 3.01 2.92 0.18 3.87 0.00 0.00 0.00 0.00 0.00 100.00
0.0013
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP C6H6 C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH TOTAL
88
0.0050 0.0029 0.0005 0.0008 0.0009 0.0009 0.0001 0.0003 0.0002 0.0000 0.0001 0.0005 0.0014 0.0020 0.0016 0.0000 0.0012 0.0000 0.0000 0.0000 0.0000 0.0000 1.00
Chapter 6
Energy Balance
6.4.3 Shell Side
Components
ni
xi
kmole/hr
H2 C1 C2 C3 n C4 nC5
Mol%
16.32 9.21 5.98 3.61 6.09 14.08
liquid Fraction
∫CpLdT
xii∫CpLdT
kJ/kmole K
kJ/kmole K
4.82
0.0075
-456122.95
-3408.41681
2.72
0.0077
-909163.18
-7029.54256
1.77
0.0082
-48009.05
-391.363277
1.07
0.0067
-18809.95
-126.759605
1.80
0.0147
-13693.05
-201.275326
4.16
0.0411
-1.24E+04
-508.97138
3.20
0.0364
-14260.24
-518.854674
n C7
1.86
0.55
0.0069
-15486.31
-106.757685
i-C4
6.84
2.02
0.0156
-15880.13
-246.956911
nC6
10.84
iC5
82.93
24.51
0.2348
-12690.75
-2980.16715
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP
35.66
10.54
0.1162
-13913.02
-1616.61507
21.85
6.46
0.0722
-13550.51
-977.749908
13.62
4.03
0.0429
-13520.48
-580.567259
2.54
0.0279
-13468.91
-376.203287
15.45
8.59
4.57
0.0560
-15940.33
-892.872845
12.80
3.78
0.0466
-15503.51
-722.528748
4.17
1.23
0.0146
-15904.92
-232.571117
7.90
2.33
0.0287
-15304.59
-438.49287
3.51
1.04
0.0124
-16066.59
-198.80811
2.99
0.88
0.0107
-15485.36
-166.463623
1.16
0.34
0.0042
-15373.62
-64.8511144
-9508.10
C6H6
0.01
0.00
0.0000
C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH
0.01
0.00
0.0000
-10953.97
2.95
0.87
0.0091
-9784.23
-88.6629931
7.73
2.28
0.0263
-11667.38
-306.572716
6.01
0.0712
-12119.17
-863.057646
0.21
0.0027
-13571.47
-36.3929815
TOTAL
20.32 0.71 19.25
0 0
5.69
0.0722
-13677.27
-987.079201
1.86
0.55
0.0066
-14725.77
-97.3980337
0.00
0.00
0.0000
-4268.44
0
0.00
0.00
0.0000
-5566.74
0
0.02
0.00
0.0004
0.0000
0
0.00
0.00
0.0000
0.0000
0
1.00
-1786381.51
338.33
100.00
89
-18726.20
Chapter 6
Energy Balance
Components
ni kmolw/hr
H2 C1 C2 C3 n C4 nC5 nC6
xi
∫CpGdT
xii∫CpGdT
Mol%
Vapor Fraction
kJ/kmole K
kJ/kmole K
4.82
0.1194
-1604.25
-77.390
2.72
0.0612
-2334.47
-63.572
1.77
0.0344
-3776.83
-66.749
1.07
0.0176
-5438.13
-58.089
1.80
0.0238
-7093.26
-127.777
4.16
0.0426
-8776.73
-365.314
3.20
0.0244
-10445.90
-334.784
16.32 9.21 5.98 3.61 6.09 14.08 10.84
n C7
1.86
0.55
0.0031
-12113.88
-66.507
i-C4
6.84
2.02
0.0283
-7142.48
-144.477
iC5
82.93
24.51
0.2632
-8769.80
-2149.795
2 MP 3 MP 2,2 DMB 2,3DMB 2 MH 3 MH 2,2 DMP 2,3 DMP 2,4 DMP 3,3 DMP 3 EP
35.66
10.54
0.0866
-10572.76
-1114.364
21.85
6.46
0.0515
-10439.68
-674.335
13.62
4.03
0.0357
-10529.97
-423.901
2.54
0.0210
-10413.12
-264.339
15.45
4.57
0.0277
-12448.77
-568.529
12.80
3.78
0.0225
-12109.92
-458.050
4.17
1.23
0.0083
-12475.50
-153.645
7.90
2.33
0.0140
2072.56
48.392
3.51
1.04
0.0070
-12109.92
-125.499
2.99
0.88
0.0054
-12109.92
-107.140
1.16
0.34
0.0020
-12109.92
-41.642
C6H6
0.01
0.00
0.0000
-6459.90
-0.155
C7H8 CP MCP CH ECP MCH 223TMB H2O C2Cl4 HCL NaOH
0.01
0.00
0.0000
-8021.26
-0.185
2.95
0.87
0.0081
-6914.30
-60.392
7.73
2.28
0.0167
-8783.19
-200.641
6.01
0.0407
-8734.52
-524.684
0.21
0.0011
-10793.30
-22.788
5.69
0.0303
-10460.21
-595.106
1.86
0.55
0.0036
-12235.86
-67.176
0.00
0.00
0.0000
0.00
0.000
0.00
0.00
0.0000
0.00
0.000
0.02
0.00
0.0000
0
0.000
0.00
0.00
0.0000
0.000
338.33
100.00
1.00
-1982.823
TOTAL
8.59
20.32 0.71 19.25
90
Chapter 6
Energy Balance
6.4.4 Calculations: TUBE SIDE
Total Enthalpy =
Sensible Heat of Liquid + Latent Heat + Sensible Heat of Vapor HL
+
HT
=
HV + HG
HG
=
HG
=
362142.117 kJ/hr
HV
=
nλ
HV
=
4178240.08 kJ/hr
HL
=
n CpLdT
HL
=
8932666.754 kJ/hr
HT
=
13473048.95 kJ/hr
HT
=
1.35E+07
n∫CpGdT
∫
kJ/hr
SHELL SIDE
Total Enthalpy =
Sensible Heat of Liquid + Latent Heat + Sensible Heat of Vapor
HT
=
HL
+
HV
HG
=
HG
=
-670852.8413 kJ/hr
HV
=
nλ
HV
=
-7941779.131 kJ/hr
HL
=
+
HG
n∫CpGdT
n∫CpLd
HL
=
-6335675.669 kJ/hr
HT
=
-14948307.64 kJ/hr
HT
=
-1.49E+07
kJ/hr
Heat Gained By Tube Side
=
Heat Lost By Shell Side
1.347E+07
=
-1.495E+07
kJ/hr
91
kJ/hr
Chapter 6
6.5
Energy Balance
ENERGY BALANCE AROUND STABILIZER T-101
Energy balance around the stabilizer has been performed following the mass balance. The reboiler duty and the condenser duties are calculated and the results are verified. Heat in + Heat generated = Heat out + Heat consumed Since there is no heat generation and consumption, therefore, Heat in = Heat out.
The enthalpy of the feed entering (Hin) the column from reference temperature Tr = 120oC Hin = 0 The distillate temperature is Td = 115oC The bottom‘s temperature is Tb = 125oC
92
Chapter 6
Energy Balance
The enthalpy of the distillate from reference temperature of 120oC is Hd = -308 kW The enthalpy of bottom product is Hb = 96 kW The reboiler duty can be calculated as Qreb = V x λ Qreb = 260 kW The saturated steam flow rate for reboiling at 1 bar is ms= Qreb/hs ms =0.13 kg/s The cooling duty of the condenser is Qcon = (L+D) x Cp x (Tavg – Td) Qcon = 50 kW The flow rate of cooling water available at 40 oC mc = Qcon/ (Cp) (Tavg – Td) mc = 2.38 kg/s
93
CHAPTER 7
PLANT DESIGN CALCULATIONS
Chapter 7
Plant Design Calculations
CHAPTER # 7 PLANT DESIGN CALCULATIONS
7.1
REACTOR
Types of Reactors The most common types of Reactors are 1. Fixed bed Reactor 2. Fluidized bed Rector 3. Stirrer tank Reactor
Fixed bed reactor can be further classified on the biases of either heat is supplied during reaction or not. i.
Adiabatic
ii.
Non adiabatic
The reactions taking place within the reactor may be in gas phase or there might a case of trickle operation. For gas phase reactions some important reactor configurations are as under. 1. Single adiabatic bed 2. Radial flow 3. Adiabatic beds in series with intermediate cooling or heating 4.
Direct-fired non-adiabatic
Except reactor type and configuration some other factors are important like , Distribution system and Sporting ceramic balls which also serves for uniform distribution of flow as well. Our Reactor in this case is non-isothermal adiabatic reactor with basket type distribution system and standard ceramic balls installation. Detailed calculations of distribution system is given in design calculations.
94
Chapter 7
7.2
Plant Design Calculations
ALGORITHM FOR DETERMINING REACTION MECHANISM AND RATE-LIMITING STEP:
Adsorption
Surface Reaction
Desorption
Assume surface reaction is rate limiting If the surface reaction is limiting then:
Site balance:
Substituting for CN-S, CI-S, and CV into CT = CV (1 + KN PN + KI PI) :
95
Chapter 7
Plant Design Calculations
where KP is the thermodynamic equilibrium constant for the reactor. Linearizing the Initial Rate:
96
Chapter 7
Plant Design Calculations
Reactor R-101 Design Reaction
n-Butane
n-Pentane
n-Hexane
n-Heptane
K KN KI
8.5
7.9
6.7
5.5
1.12
1.2
1.6
1.75
13
11
9
8
Pressure P Temperature T Compressibility Factor Z Universal Gas Constant R Molar Flow rate Fo
2300 443 0.8392 8.314 394.58
kPa K
Volume Flow Rate
530.26
kPa/kmol K kmol/hr m3/hr
Overall Concentration
744.13
mol/dm3
Stream 7 Components
Mole Fraction
Molar Flow Rate
n-Butane n-Pentane n-Hexane n-Heptane
0.0309 0.1476 0.117 0.0588
12.19 58.25 46.18 23.22
Volumetric Flow Fao Concentration CAo Conversion X 16.38 78.27 62.04 31.18
22.9936 109.8335 87.0632 43.7548
0.5 0.75 0.765 0.919
WB
209.9
kg
WH
281.823
kg
WP
357.159
kg
WHe
330.038
kg
WT
1178.92
kg
V
Weight of catalyst
packing density
x 1.6
1.6 is a designing factor for catalytic Reactor V
2.3727
3
m
97
Chapter 7
Plant Design Calculations
PRESSURE DROP IN REACTOR R-101
Using ERGUN equation for the pressure drop in packed bed reactors
For the given reactor Length to dia Ratio L/D Diameter D Length L
5.000 0.845 4.227
m m
2.773 13.864
ft ft
Area A
0.561
m2
6.039
ft2
Volume V
2.373
m3
83.726
ft3
For Feed of R-101 Density ρ Molecular Mass M Inlet Molar Flow Rate Fo Outlet Molar Flow Rate F
73.560 65.410 394.580 338.3
kg/m3
4.586
lb/ft3
kmol/h kmol/h
109.606 93.972
mol/s mol/s
Pressure P Temperature T Viscosity μ Compressibility Factor Z
2300.000 170.000 8.320E-06 0.839 12.772
kPa C lb/ft s
48049.741 443.000
lbf/ft K
Mass Flux G βo α dy/dw
475.371 0.000 1.12451E-05
y
0.986664298
Pressure at outlet P Pressure Drop ∆P
kg/m2 s
1/y
2269.327886
kPa
30.672
kPa
98
2.612
2
2
lb/ft s
Chapter 7
Plant Design Calculations
Reactor R-102 Design
Reaction
n-Butane
n-Pentane
n-Hexane
K KN KI
8.5
7.9
6.7
5.5
1.12
1.2
1.6
1.75
13
11
9
8
Pressure P
2210
kPa
Temperature T
393
K
Compressibility Factor Z
0.9808
Universal Gas Constant R
8.314
kPa/kmol K
Molar Flow rate Fo
338.32
kmol/hr
Volume Flow Rate
490.59
Overall Concentration
689.62
m3/hr mol/dm3
n-Heptane
Stream 9 Components
n-Butane n-Pentane n-Hexane n-Heptane
Mole Fraction
Molar Flow Rate
0.0180 0.0416 0.0320 0.0055
6.09 14.08 10.84 1.86
Volumetric Flow Fao Concentration CAo Conversion X 8.84 20.42 15.72 2.69
12.4227 28.7040 22.1019 3.7861
0.4201 0.7183 0.7263 0.9067
WB
391.619
kg
WH
937.904
kg
WP
920.785
kg
WHe
1547.613
kg
WT
3797.921
kg
V
Weight of catalyst
packing density
x 1.6
1.6 is a designing factor for catalytic Reactor V
7.64
3
m
99
Chapter 7
Plant Design Calculations
PRESSURE DROP IN REACTOR R-102
Using ERGUN equation for the pressure drop in packed bed reactors
For the given reactor Length to dia Ratio L/D Diameter D Length L
5.000 1.249 6.243
m m
4.095 20.476
ft ft
Area A
1.224
m2
13.173
ft2
Volume V
7.644
m3
269.724
ft3
For Feed of R-101 3
Density ρ Molecular Mass M Inlet Molar Flow Rate Fo Outlet Molar Flow Rate F Pressure P
27.340 73.950 338.320 338.3 2210.000
kg/m
Temperature T Viscosity μ Compressibility Factor Z
46169.534 120.000 7.160E-06 0.839 5.676
lbf/ft C lb/ft s
Mass Flux G βo α dy/dw
262.053 0.000 3.44951E-06
y
0.995928192
Pressure at outlet P Pressure Drop ∆P
2201.001304 8.999
kmol/h kmol/h kPa
3
1.705
lb/ft
93.978 93.972
mol/s mol/s
393.000
K
2
kg/m2 s
1/y
kPa kPa
100
1.161
2
lb/ft s
Chapter 7
7.3
Plant Design Calculations
DESIGNING OF NAPHTHA FEED PUMP:
A pump is one of the most important pieces of mechanical equipment that is present in industrial processes. A pump moves liquid from one area to another by increasing the pressure of the liquid above the amount needed to overcome the combined effects of friction, gravity and system operating pressures.
There are two types of pump which are generally used in industrial processes: positive displacement pump and centrifugal. It is important to choose the suitable type of pump based on process requirement and fluid process properties.
In designing the pump, the knowledge of the effect of parameters; such as pump capacity, NPSH, pumping maximum temperature, specific gravity, fluid viscosity, fluid solid content, and the other process requirements are very important. All of these parameters will affect the selection and design of the pump which will affect the performance of the pump in the process.
NPSH as a measure to prevent liquid vaporization or called cavitation of pump. Net Positive Suction Head (NPSH) is the total head at the suction flange of the pump less the vapor pressure converted to fluid column height of the liquid.
Naphtha feed is coming from the atmospheric distillation column is treated with hydrogen and brought to a pressure about 4 bar. This stream is then raised to a pressure of 24 bar using a centrifugal compressor. The design of pump is carried out using energy balance (extended Bernoulli‘s equation) and the power of the pump is calculated.
101
Chapter 7
Plant Design Calculations
The stream at the inlet of the pump is at given conditions and rates specified.
Inlet pressure Outlet pressure Temperature Density Viscosity Mass flow rate Molar flowrate Volumetric flowrate Vapour pressure
4 24 35 664.8 1.037 25000 301 37.605 69.6
P1 P2 T ρ μ m F Q Pv
bar bar °C Kg/m3 Kg/m hr Kg/hr Kmol/hr m3/hr kPa
The optimum diameter of the pipe is found against given flow rate using the graph Dopt = 0.1061 m The velocity of the fluid through the pump is given by 4XQ πD2
V =
(m/s)
V = 1.289 m/s The work done per unit mass is given by the extended Bernoulli‘s equation. ∆W = (∆P/ ρ) + (∆PF/ ρ) + (∆V/2g) (J/kg) ∆W= (2000000/664.8) + (∆PF/664.8) + (0) The pressure drop due to the friction is given by the Darcy‘s equation ∆PF
=
8 x f x L x V2 x ρ 2xD
For relative roughness (є) =0.046 m Friction factor (f) = 0.002 An assumed length of 100 m from pump outlet to the inlet of the reactor ∆PF = 8670 N/m2 hence the work done per unit mass is 102
Chapter 7
Plant Design Calculations
∆W =2419.82 N/m2 The total work is given by taking efficiency of pump (η)=0.7 W = (∆W x m)/ η W = 2419.82 x 25000/ (3600 x 0.7) W = 24 KW or 32 hp The Net positive suction head of the pump can be found by using the formula NPSHavail = (P1/ρg) – (ΔPf/ρg) – (Pv/ρg) NPSHavail = 49.37 m
103
Chapter 7
7.4
Plant Design Calculations
HEAT EXCHANGER DESIGN:
Heat exchanger E-101 is installed to recover the heat of the effluent from reactor R101 and heat the naphtha feed to bring it to the required temperature. The hot stream which is coming from R-101 is at a temperature of 1750C and the cold stream is the preheated naphtha feed coming from E-101 and is at a temperature of 78.21. The hot stream is cooled to 1200C which is the required inlet temperature for R-102. Hence the outlet temperature of naphtha feed can be determined. The physical properties of both the streams are found at their mean temperatures. The first iteration is done by assuming a constant specific heat; this is used to find the final temperature of the naphtha stream to be 1120C. Cold stream (Naphtha feed) 0
Inlet temperature (t1)
=
78.21
C
Outlet temperature (t2)
=
120
Molar flow rate (n)
=
338.316
Molecular mass (M)
=
67
Specific heat (Cp)
=
161.75
kJ/kg. k
Viscosity (µ)
=
1.50E-5
Ns/m2
Density (ρ)
=
112.36
kg/m3
Conductivity (k)
=
0.091205
W/m k
Inlet temperature (T1)
=
175
0
C
Outlet temperature (T2)
=
120
0
C
Molar flow rate (n)
=
394.58
Molecular mass (M)
=
74
Specific heat (Cp)
=
162.4
kJ/kg. k
Viscosity (µ)
=
1.01E-05
Ns/m2
Density (ρ)
=
12.75
kg/m3
Conductivity (k)
=
2.86E-02
W/m k
0
C
kmol/hr
Hot stream (effluent R-101)
104
kmol/hr
Chapter 7
Plant Design Calculations
Tubes of BWG 14 are selected the specifications are Outer diameter (do)
=
0.016
m
Inner diameter (di)
=
0.0117836
m
Tube thickness (t)
=
0.0021082
m
Tube length (L)
=
5
m
The true temperature is found by ∆T = F x ∆Tm ∆Tm
(T2-t1)-(T1-t2) Ln (T2-t1/T1-t2)
=
∆Tm = 51.671510020C F can be found by using graph for two tube passes and one shell pass F= 0.88 ∆T = 0.88 x 51.671510020C ∆T = 45.47oC The heat transfer area is given by Q = 2.6 E+6 KJ/hr Q A =
U x ∆T
Assume U= 1000 KJ/m2 k A = 52.78 m2 Number of tubes =
Number of tubes (Nt)
A π x I.D x L =
210
Number of tubes per pass (Np) =
105
Bundle diameter = do x ( Nt/k )1/n
105
Chapter 7
Plant Design Calculations
For two tube passes k= 0.249 and n=2.207 Bundle diameter (Db)
=
0.3388 m
From graph at given bundle diameter clearance =0.0133 m Shell diameter (Ds) = bundle diameter +shell clearance Shell diameter
=
0.3522 m
=
5
For tube pitches of 1.25 do Number of baffles (b)
Baffle spacing (lb) = L/number of baffles Baffle spacing
=
0.0705 m
Flow area at shell side (As) = (0.25 x di x lb x tubes at central plane) Tubes at central plane = bundle diameter/ tube pitch Tubes at central plane
=
17
Shell flow area
=
0.00477 m2
Hence,
The equivalent diameter of shell (de) = 4 x hydraulic radius The equivalent diameter of shell = .02565 m The tube side and shell side velocities can be found by using formula Velocity = mass flow/ (density x area) Us = 0.031733114 m/s Ut = 5.707451295 m/s Finding tube side heat transfer co=efficient hi = (k/do)(jh x Re x Pr0.33) Reynolds number (Re) = (ρ x di x Ut)/ µ Prandalt‘s number (Pr) = (Cp xµ)/k Re = 500000 Pr=0.02664 hi = 2707.3 106
Chapter 7
Plant Design Calculations
Finding shell side heat transfer co=efficient ho = (k/de)(jh x Re x Pr0.33) Re = 3700000 Pr = 0.057 ho = 2811.45 Overall heat transfer coefficient U = (1/hi) +(1/ho) (di/do) + (t x di)/(kt x dw) dw = (di +do)/2 kt= 15 W/m k U = 981 KJ/m2 k Pressure drop at tube side Pt= Np ((8 x jf (L/d) +2.5)x(ρ x Ut))/2 Pt=1000 Pa Shell side pressure drop Ps= 8 x Jf x (Ds/de) x (L/lb) x (ρUs2/2) Ps=440 Pa
107
Chapter 7
7.5
Plant Design Calculations
DESIGNING OF STABILIZER T-101:
The naphtha stabilizer column is designed as a distillation column. The feed is the stream coming from the heat exchanger E-102. The stream temperature is 120oC and a pressure of 18.5 bara. The feed of the column is fractionated and the product are obtained as specified in the figure.
The method used for design is HENGTEBECK‘S METHOD, it is a modification to the binary MC‘CABE AND THIELE method for binary distillation. The key components selected are butane (iso and normal) and iso pentane. The heavier key is iso-pentane and lighter key is butane stream.
KEYS
FEED FLOW RATE (F)
DISTILLATE FLOW RATE (D)
BOTTOMS FOW RATE (B)
Butane (LK)
12.996
12.9013
0.0946
ISO PENTANE (HK)
94.234
0.9420
93.292
108
Chapter 7
Plant Design Calculations
COMPOSITIONS: The molar fractions of butane and isopentane according to HENGTEBECK‘S METHOD in the streams are given as Feed
distillate
bottoms
Butane
0.12
0.9315
0.001
Iso pentane
0.88
0.0685
0.999
Using Antoine equation at column average temperature the saturation pressure of the key components is found to be Psatbutane= 15810 mm Hg Psatiso pentane= 1480 mm Hg Relative volatility of the stream with respect of the heavier key αavg= 10.68 The expression for the vapor liquid equilibrium relation is given as y=
αx 1+(α-1)x
Using this data and developing a table for liquid vapour equilibrium curve Liquid fraction 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Vapor fraction 0 0.546 0.7275 0.8206 0.8769 0.9143 0.9412 0.9614 0.9771 0.9897 1.0
Using MC‘CABE AND THIELE method for pseudo binary distillation for Reflux ratio=5 Feed at bubble point=120oC
feed line is vertical 109
Chapter 7
Plant Design Calculations
Intercept of top operating line= (xd)/(R+1) Intercept of top operating line= 0.155 Number of ideal plates= 7 Feed plate= 5th Efficiency of column According to O‘CORNELL‘S equation, the overall efficiency of the column can be estimated by the relation Eo= 51-32.5log(µavgαavg ) µavg=(0.12x0.104)+(0.88x0.104) µavg=0.104 mNs/m2 Using given equation the overall efficiency of the column is found to be EO=45% Actual number of plates = 14 Column diameter calculations The diameter of the column is calculated by using the formula for vapor flow through a cylinder Diameter of column =
(4 x molar flow of vapors x mol.massavg)1/2 (ρg x V‘x π)1/2
For bottom of the column Mavg= 84.32 Molar flow rate = (R+1) D Molar flow rate = 292.5 kmol/hr ρg = 47.44kg/m3
using general gas equation
ρl = 550 kg/m3 V‘= K (ρl/ ρg -1)1/2 K can be found for 18 inches (460mm) tray spacing to be 0.135 V‘=0.437m/s Diabottom = 0.65m (2.13 ft) 110
Chapter 7
Plant Design Calculations
For top of the column Mavg= 76 Molar flow rate = (R+1) D Molar flow rate = 292.5 kmol/hr ρg = 44kg/m3
using general gas equation
ρl = 480kg/m3 V‘= K (ρl/ ρg -1)1/2 K can be found for 18 inches (460mm) tray spacing to be 0.252 V‘=0.6295m/s Diatop = 0.0.532 m (1.74 ft) The minimum diameter of the column must be 0.65 m Height of the column height of the column can be approximated as LC =tray spacing x number of trays LC =6.1 m appx Pressure drop Pressure drop across each plate is given by the relation ∆P =(9.81 X 10-3)( ht)( ρl)
Where, ht = hd+hw+how+hr hd = dry pressure drop (due to friction) hw = weir height how = weir crest ( liquid level above weir) hr = residual pressure drop taking weir height hw =50 mm (2 inches) 111
Chapter 7
Plant Design Calculations
weir length = 0.7 x Dc weir length = 0.455m since, hd = 51(Va/Co)2(ρg/ ρl) Co = 0.84
(for 10% downcomer area, & hole dia/ plate thickness = 1)
hd= 119.6 mm how =(750 Lw)/( ρlxlw) how = 135mm hw = 50mm hr = (1.25 x 10-3)/ ρl hr = 2.38 mm ht = 307 mm ∆P =(9.81 X 10-3)( 307)( 525) ∆P =1581 Pa (0.23psi) Total pressure drop across column ∆Pc ∆Pc = 1581 x 14 ∆Pc = 22120 Pa (3.2 psi)
Column specifications Number of plates Column diameter Tray spacing Height of column Weir height Pressure drop Downcomer area
14 0.65 m 460 mm (18 inches) 9.10 m 50 mm (2 inches) 22.12 Kpa (3.2 psi) 10%
112
Chapter 7
7.6
Plant Design Calculations
DESIGNING OF HYDROGEN FEED COMPRESSOR K-101:
Pressure At Different Stages
Q
Q
Q
113
Chapter 7
Plant Design Calculations
For First Stage
γ = Cp/(Cp-R) γ
114
Chapter 7
Plant Design Calculations
W = W/Ep
For Second Stage
γ = Cp/(Cp-R) γ
115
Chapter 7
Plant Design Calculations
W = W/Ep
For Third Stage
γ = Cp/(Cp-R) γ
116
Chapter 7
Plant Design Calculations
W = W/Ep
117
Chapter 7
Plant Design Calculations
For Fourth Stage
γ = Cp/(Cp-R) γ
W = W/Ep
118
Chapter 7
Plant De sign Calculations
Total Work & Power
118
CHAPTER 8
COST ESTIMATION
Chapter 8
Cost Estimation
CHAPTER # 8 COST ESTIMATION
8.1
COST ESTIMATION:
Feasibility means that the project being considered is technically possible. Economic feasibility, in addition to acknowledging the technical possibility of a project, further implies that it can be justified on an economic basis as well. Economic feasibility measures the overall desirability of the project in financial terms and indicates the superiority of a single approach over others that may be equally feasible in a technical sense. The cost analysis of an industrial process includes capital investment cost, manufacturing cost and general expense such as income taxes. 8.1.1
Capital investments:
Before an industrial plant can be put into operation, large amount of money must be supplied to purchase and install the necessary machinery and equipment, land and service facilities must be obtained and the plant must be erected. Complete with all pipe controls inn services. In addition it is necessary to have money available for payment of expenses involved in the plant operation. 8.1.2
Fixed capital:
Fixed capital is that portion of the total capital that is invested in fixed assets (such as land, buildings, vehicles, and equipment) that stay in the business almost permanently. The capital needed to supply the necessary manufacturing and plant facilities is called the fixed-capital investment It includes
capital necessary for the installed process equipments
All design and construction overheads supervision
All piping, instruments and controls
insulation, foundations, and site preparation
119
Chapter 8
Cost Estimation
land, processing buildings, administrative, and other offices, warehouses, laboratories.
Auxiliary facilities, such as utilities, land and civil engineering work
The fixed capital investment classified in to two sub divisions.
i.
Direct Cost
ii.
Indirect Cost
8.1.3
Working capital:
Working capital is additional investment which represents operating liquidity available to a processing plant. It includes the cost of
Startup
Initial catalyst charge
raw materials and supplies carried in stock
Inventories of intermediates and products
cash kept on hand for monthly payment of operating expenses, such as salaries, wages etc.
Payable accounts and taxes.
The total capital investment is the sum of fixed and working capital. The ratio of working capital to total capital investment varies with different companies, but most chemical plants use an initial working capital amounting to 10 to 20 percent of the total capital investment. This percentage may increase to as much as 50 percent or more for companies producing products of seasonal demand because of the large inventories which must be maintained for appreciable periods of time.
By far the most important item is the raw material expense. Labor is the component of immediate secondary magnitude. This increased by the fact that pay role over head
120
Chapter 8
Cost Estimation
and plant overhead are always calculated fraction of labor expense and that laboratories charges and supervision maybe estimated similarly if one chooses. Depreciation, property taxes, insurance and sometimes maintenance and plant supplied are estimated from the fixed capital investment. Individually there are small in the manufacturing cost, but together they can represent a sizable total- Utilities take collectively represent an amount of relative importance in a manufacturing cost. Royalties on the average are small but should be carefully conceded when large. Similarly, shipping is usually minor. Packaging expenses are usually small since the petrochemical industry is primarily bulk supplier. However in particular face of the industry packaging may prove to be of major importance. General expenses are a sizable portion of total cost, can be estimated as percentage of manufacturing cost.
8.1.4
Direct cost:
Purchased Equipment Cost = E Component Purchased equipment Installation Instrumentation (installed) Piping (installed) Electrical (installed) Building (including Service) Yard improvement Service facilities
Percentages of ‗Purchased Equipment Cost‘ (E) 47 % 12 % 66 % 11 % 18 % 10 % 70 %
Total Direct Cost = D 8.1.5
Indirect cost:
Engineering and supervision
33 % E
Construction Expenses
46 % E
Total Indirect cost
I
Total Direct and Indirect Cost
D+I
Contractor‘s Fees
5 % (D+I) = x
121
Chapter 8
Cost Estimation
Contingency
10 % (D+I)=y
Fixed Capital investment
D+I+x+y
Working Capital Investment
0.15 * (D+I+x+y)
Total Plant Cost (TPC)
8.2
Fixed Capital + Working Capital
Land Cost
2 * TPC
Total Cost
TPC + Land Cost
COST ESTIMATION OF OUR PLANT:
Cost of Equipment: Cost of 2012 = cost of 2007 × (Index 2012/ Index 2007) Cost Index of year 2007 = 525.4 Cost Index of year 2012 = 593.8
Equipment Purchased Cost (E): Equipment Drier Mixer Compressor pump Exchanger E-101 Exchanger E-102 Exchanger E-103 Reactor R-101 Reactor R-102 Distillation Column Scrubber Total 8.2.1
2007 Cost (US $) 12600 7800 128400 7900 183500 183500 183500 31100 56300 53300 4200 852100
2012 Cost (US $) 14240.35021 8815.454892 145115.9498 8928.473544 207389.2273 207389.2273 207389.2273 35148.80091 63629.50133 60238.94176 4746.783403 963031.9376
Direct cost estimation: Purchased equipment installation
452625.0107 $
Instrumentation installation
115563.8325 $
Piping installed
636501.0788 $ 122
Chapter 8
8.2.2
Cost Estimation
Electrical installed
105933.5131 $
Building including services
173345.7488 $
Yard improvement
96303.19376 $
Service facilities
674122.3563 $
Total direct cost
2253494.734 $
Indirect cost estimation: Engineering and supervision
317800.5394 $
Construction expenses
394843.0944 $
Total direct and indirect cost
2966138.368 $
Miscellaneous, Contractors fee
148306.9184 $
Contingency
2966138.8368 $
Total plant cost
3922717.991 $
Land cost
7845345.983 $
Total cost
11768153.97 $
Including present worth of catalyst for 4 years life, and given plant life of 16 years at rate of $ 196/kg. Present worth of catalyst
1611366
$
Miscellaneous
4541961.6
$
Annual revenues For 24500 kg/hr and a production capacity of 24 hours a day and 300 days a year Inflows
37849680
$
Electricity
651183.16
$
Salaries and wages
65684.211
$
Income tax (40%)
15139872
$
Annual expenses
123
Chapter 8
Cost Estimation
Sales tax (16%)
8.2.3
6055948.8
$
Net annual revenues
=
inflows – outflows
Net annual revenues
=
12152024
$
Payback period:
Calculating discounted payback period at a MARR of 25%. End of year 1
=
-3657901
$
End of year 2
=
4119394.4
$
Hence 2nd year is the payback period.
8.3
ECONOMICS OF PLANT LOCATION:
The final choice of the plant site usually involves a presentation of the economic factors for several equally attractive sites. The exact type of economic study of plant locations will vary with each company making a study. It should include the following: 8.3.1
Investment:
Plant
New Money
Existing facilities
Working capital
Annual sales
Cost
Manufacturing
Distributing
Selling
Research
Annual Earnings
Operative
Net after taxes
Net annual return on total investment
124
Chapter 8
Cost Estimation
The limitations of preliminary plant location cost studies should be recognized pointed out a management. No matter how carefully a survey is prepared, future trends such as population and marketing shifts, development of competitive processes and the advent of new industries. Services and transportation facilities cannot be reliably predicated. 8.4
PLANT LOCATION AND SITE SELECTION:
The location of plant has a crucial effect on the profitability of project and the scope for future expansion. Many factors are considered when selecting a suitable site. A brief explanation of each factor is given below: 8.4.1
Raw Materials Supply:
Probably the location of the raw materials of an industry contributes more towards the choice of a plant site than any other factor. This is especially noticeable in those industries in which the raw material is inexpensive and bulky and is made more compact and obtains a high bulk value during the process of manufacturing. 8.4.2
Marketing Area:
For materials that are produced in bulk quantities, such as cement, minerals acids and fertilizers, where the cost of e product per ton is relatively low and cost of transportation has a significant fraction of the sale price. The plant should be located closed to the primary market. This consideration will be less important for low volume production, high price product such as pharmaceuticals. 8.4.3
Transportation Facilities:
The Transport of material and products to and from the plant will be overriding consideration in site selection. If practicable, a site should be selected that is closed to at least two major forms of transport, road, rail, water way (canal or river) or a sea port. Road transport is being increasingly used and is suitable for local distribution from a central ware house. Rail transportation will be cheaper for long distance transport of bulk chemicals. Air transport is convenient and efficient for the movement of personnel and essential equipment and supplies and the proximity of the site to a major airport should be considered.
125
Chapter 8
8.4.4
Cost Estimation
Sources of Power:
Power for chemical industry is primarily from coal, water and oil; these fuels supply (he most flexible and economical sources, in as much as they provide for generation of steam both for processing and for electricity production power can be economically developed as a by-product in the most chemical plants. If the needs are great enough, since the process requirements generally call for lowpressure steam. The turbines of engines used to generate electricity can be operated non-condensing and supply exhaust steam for processing purposes. 8.4.5
Availability of Labor:
Labor will be needed for construction of the plant and its operation. Skilled construction workers will usually be brought in from outside the site area, but here should be an adequate pool of unskilled labor available locally; and lab our suitable for training to operate plant. Skilled tradesmen will be needed for plant maintenance. Local trade union customs and restrictive practices will have to be considered when assessing the availability and suitability of the local labor for recruitment and training. 8.4.6
Water Supply:
Water for industrial purpose can be obtained from one of two general sources: the plant's own source or municipal supply. If the demand for water is larger, it is more economical for the industry to supply its own water. Such a supply may be obtained from drilled wells, rivers, lakes, dammed streams or other impounded supplies. Before a company enters upon any project, it must ensure itself of a sufficient supply of water for all industrial, sanitary and fire demands, both present and future. 8.4.7
Effluent Disposal:
All industrial process produce waste products and full consideration must be given to the difficulties and cost of their disposal. The disposal of toxic and harmful effluents will be covered by local regulations and appropriate authorities must be consulted during the initial site survey to determine the standards that must be met.
126
Chapter 8
8.4.8
Cost Estimation
Local Community Considerations:
The proposed plant must fit in with and be acceptable to the local community. Full consideration must be given to the safe location of the plant so that it dies not impose a significant additional risk to the community. On a new site, the local community must be able to provide adequate facilities for, the plant personnel: school, banks, housing and recreational and cultural facilities. 8.4.9
Land Considerations:
Sufficient suitable land must be available for the proposed pant and for future expansion. The land should ideally be flat, well drained and have suitable load bearing characteristics. A full site evaluation should be made to determine the need for piling or other special foundation. 8.4.10 Climate: Adverse climatic conditions at a site will increase costs. Abnormally low temperature will require the provision of additional insulation and special heating for equipment and pipe runs. Stronger structures will be need at locations subjected to strong winds (cyclone hurricane areas) or earthquakes. 8.4.11 Political and Strategic Considerations: Capital grants, tax concessions, and other inducements are often given by government's direct new investment to preferred locations such as areas of high unemployment. The availability of such grants can be over-riding consideration site selection.
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Environment And Safety
CHAPTER # 9 ENVIRONMENT AND SAFETY Petroleum refining is one of the largest industries and a vital part of the national economy. However, potential environmental hazards associated with refineries have caused increased concern for communities in close proximity to them. This update provides a general overview of the processes involved and some of the potential environmental hazards associated with petroleum refineries. 9.1
DEFINITION OF A PETROLEUM REFINERY:
Petroleum refineries separate crude oil into a wide array of petroleum products through a series of physical and chemical separation techniques. These techniques include fractionation, cracking, hydro treating, combination/blending processes, and manufacturing and transport. The refining industry supplies several widely used everyday products including petroleum gas, kerosene, diesel fuel, motor oil, asphalt, and waxes. 9.2
BACKGROUND:
A refinery is an industrial plant for purifying a crude substance. The refining sector investment in Pakistan has been almost nonexistent since the 1960s.In the late 90s, Pakistan‘s refining capacity was less than 150k bbl. /day. Pakistan imported over 60% of
its
total
POL
product
consumption.
capacity stands slightly below 300Kbb/day. This
At present, Pakistan‘s was
mainly
due
refining to the
commencement of PARCO in the late 2000.Almost the refineries work at around 80% capacity except Byco, which just utilized 45% of its capacity. NRL and PPl operate at full capacity. Inspite of current condition there is a general lack of refineries; where Pakistan is facing a deficit 100,000 to 150,000 barrels a day in refining fuel oil and diesel. There are certain standards that are followed internationally known as EURO 2 and EURO 4 that relate to environmental cleanliness. Neither of these is followed in Pakistan. The major players or the 5 refineries under OCAC (Oil Companies Advisory Committee) are: 1. Pak Arab Refinery Complex 2. National Refinery Limited 129
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3. Pakistan Refinery Limited 4. Attock Refinery Limited 5. Byco Refinery Limited Two refineries that have been introduced and don‘t come under OCAC. Enar Petrotech Services Limited and Dohaka Refinery Limited.
9.3
PROCESSES INVOLVED IN REFINING CRUDE OIL:
The process of oil refining involves a series of steps that includes separation and blending of petroleum products. The five major processes are briefly described below: 9.3.1
Separation Processes:
These processes involve separating the different fractions/ hydrocarbon compounds that make up crude oil based on their boiling point differences. Crude oil generally is composed of the entire range of components that make up gasoline, diesel, oils and waxes. Separation is commonly achieved by using atmospheric and vacuum distillation. Additional processing of these fractions is usually needed to produce final products to be sold within the market. 9.3.2
Conversion Processes:
Cracking, reforming, coking, and visbreaking are conversion processes used to break down large longer chain molecules into smaller ones by heating or using catalysts. These processes allow refineries to break down the heavier oil fractions into other light fractions to increase the fraction of higher demand components such as gasoline, diesel fuels or whatever may be more useful at the time.
9.3.3
Treating:
Petroleum-treating processes are used to separate the undesirable components and impurities such as sulfur, nitrogen and heavy metals from the products. This involves processes such as hydro treating, deasphalting, acid gas removal, desalting, hydrodesulphurization, and sweetening.
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9.3.4
Environment And Safety
Blending/Combination Processes:
Refineries use blending/combination processes to create mixtures with the various petroleum fractions to produce a desired final product. An example of this step would be to combine different mixtures of hydrocarbon chains to produce lubricating oils, asphalt, or gasoline with different octane ratings. 9.3.5
Auxiliary Processes:
Refineries also have other processes and units that are vital to operations by providing power, waste treatment and other utility services. Products from these facilities are usually recycled and used in other processes within the refinery and are also important in regards to minimizing water and air pollution. A few of these units are boilers, wastewater treatment, and cooling towers. 9.4
ENVIRONMENTAL HAZARDS OF PETROLEUM REFINERIES:
Refineries are generally considered a major source of pollutants in areas where they are located and are regulated by a number of environmental laws related to air, land and water. Some of the regulations that affect the refining industry include the following Laws, Rules and Regulations have been issued under the Pakistan Environmental Protection Act, 1997. 9.4.1
Rules:
National Environmental Quality Standards (self-monitoring and Reporting by Industries) Rules, 2001
Provincial Sustainable Development Fund (Procedure) Rules, 2001
Pakistan Sustainable Development Fund (Utilization) Rules, 2001
Provincial Sustainable Development Fund (Utilization) Rules, 2003
Pollution Charge for Industry (Calculation and Collection) Rules, 2001
Environmental Tribunal Rules, 1999
Environmental Tribunal Procedures and Qualifications Rules, 2000
Environmental Samples Rules, 2001 131
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Hazardous Substances Rules, 2000
Hazardous Substances Rules, 2003
9.4.2
Regulations : Review of IEE/EIA Regulations, 2000 Pakistan Environmental Protection Agency (Review of IEE1EIA) Regulations, 2000
National Environmental Quality Standards (Environmental Laboratories Certification) Regulations, 2000
National Environmental Quality Standards Draft Hospital waste Management Rules Draft Composition of Offences and Payment of Administrative Penalty Rules, 1999
9.4.3
Policies &Strategies:
National Environment Policy
National Resettlement Policy March, 2002 (Draft)
National Drinking water Policy (Draft)
National Drinking water Policy
Clean Development Mechanism (CDM)
National Operational Strategy
Here is a breakdown of the air, water, and soil hazards posed by refineries: 9.4.4
Air Pollution Hazards:
Petroleum refineries are a major source of hazardous and toxic air pollutants such as BTEX compounds (benzene, toluene, ethyl benzene, and xylem). They are also a major source of criteria air pollutants: particulate matter (PM), nitrogen oxides (Knox), carbon monoxide (CO), hydrogen sulfide (H2S), and sulfur dioxide (SO2). Refineries also release less toxic hydrocarbons such as natural gas (methane) and other light volatile fuels and oils. Some of the chemicals released are known or suspected cancercausing agents, responsible for developmental and reproductive problems. They may 132
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also aggravate certain respiratory conditions such as childhood asthma. Along with the possible health effects from exposure to these chemicals, these chemicals may cause worry and fear among residents of surrounding communities. Air emissions can come from a number of sources within a petroleum refinery including: equipment leaks (from valves or other devices); high-temperature combustion processes in the actual burning of fuels for electricity generation; the heating of steam and process fluids; and the transfer of products. Many thousands of pounds of these pollutants are typically emitted into the environment over the course of a year through normal emissions, fugitive releases, accidental releases, or plant upsets. The combination of volatile hydrocarbons and oxides of nitrogen also contribute to ozone formation, one of the most important air pollution problems in the United States. 9.4.5
Water Pollution Hazards:
Refineries are also potential major contributors to ground water and surface water contamination. Some refineries use deep-injection wells to dispose of wastewater generated inside the plants, and some of these wastes end up in aquifers and groundwater. These wastes are then regulated under the Safe Drinking Water Act (SDWA). Wastewater in refineries may be highly contaminated given the number of sources it can come into contact with during the refinery process (such as equipment leaks and spills and the desalting of crude oil). This contaminated water may be process wastewaters from desalting, water from cooling towers, storm water, distillation, or cracking. It may contain oil residuals and many other hazardous wastes. This water is recycled through many stages during the refining process and goes through several treatment processes, including a wastewater treatment plant, before being released into surface waters. The wastes discharged into surface waters are subject to state discharge regulations and are regulated under the Clean Water Act (CWA). These discharge guidelines limit the amounts of sulfides, ammonia, suspended solids and other compounds that may be present in the wastewater. Although these guidelines are in place, sometimes significant contamination from past discharges may remain in surface water bodies. 9.4.6
Soil Pollution Hazards:
Contamination of soils from the refining processes is generally a less significant problem when compared to contamination of air and water. Past production practices 133
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may have led to spills on the refinery property that now need to be cleaned up. Natural bacteria that may use the petroleum products as food are often effective at cleaning up petroleum spills and leaks compared to many other pollutants. Many residuals are produced during the refining processes, and some of them are recycled through other stages in the process. Other residuals are collected and disposed of in landfills, or they may be recovered by other facilities. Soil contamination including some hazardous wastes, spent catalysts or coke dust, tank bottoms, and sludge from the treatment processes can occur from leaks as well as accidents or spills on or off site during the transport process.
9.5
MATERIAL SAFETY DATA SHEET:
Material name:
Light Straight Run Naphtha
Synonym(s):
LSR; LSR Gasoline; Light Straight Run; Light Straight Run Gasoline; Gasoline - Straight-Run, Topping-Plant
Physical State Liquid. Appearance Colorless to light yellow liquid. 9.5.1
Emergency Overview DANGER!
Extremely flammable liquid and vapor - vapor may cause flash fire. Will be easily ignited by heat spark or flames. Heat may cause the containers to explode. Harmful if inhaled, absorbed through skin, or swallowed. Aspiration may cause lung damage. Irritating to eyes, respiratory system and skin. In high concentrations, vapors and spray mists are narcotic and may cause headache, fatigue, dizziness and nausea.
Contains benzene, Cancer hazard, Mutagen, may cause heritable genetic damage. May cause adverse reproductive effects -such as birth defects, miscarriages, or infertility. Hydrogen sulfide, a highly toxic gas, may be present or released. Signs and symptoms of overexposure to hydrogen sulfide include respiratory and eye irritation, dizziness, nausea, coughing, a sensation of dryness and pain in the nose, and loss of consciousness. Odor does not provide a reliable indicator of the presence of hazardous levels in the atmosphere. Prolonged exposure may cause chronic effects. Toxic to aquatic Organisms. May cause long-term adverse effects in the aquatic environment. 134
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9.5.2
Environment And Safety
OSHA Regulatory Status:
This product is considered hazardous under 29 CFR 1910.1200 (Hazard Communication).
9.5.3
Potential Health Effects:
9.5.3.1 Eyes: Contact may irritate or burn eyes. Eye contact may result in corneal injury.
9.5.3.2
Skin:
Harmful if absorbed through skin. Irritating to skin. Frequent or
prolonged contact may defat and dry the skin, leading to discomfort and dermatitis.
9.5.3.3
Inhalation:
Harmful if inhaled. Irritating to respiratory system. In high
concentrations, vapors and spray mists are narcotic and may cause headache, fatigue, dizziness and nausea. May cause breathing disorders and lung damage. May cause cancer by inhalation. Prolonged inhalation may be harmful.
9.5.3.4 Ingestion: Harmful if swallowed. Ingestion may result in vomiting; aspiration (breathing) of vomiting into lungs must be avoided as even small quantities may result in aspiration pneumonitis. Irritating to mouth, throat, and stomach.
9.5.3.5
Target organs: Blood. Eyes. Liver, Respiratory system, Skin, Kidneys,
Central nervous system.
9.5.3.6
Chronic effects:
Cancer hazard. Contains material which may have
reproductive toxicity, teratogenetic or Mutagenic effects. Liver injury may occur. Kidney injury may occur. May cause central nervous system disorder (e.g., narcosis involving a loss of coordination, weakness, fatigue, mental confusion and blurred vision) and/or damage. Frequent or prolonged contact may defat and dry the skin, leading to discomfort and dermatitis.
9.5.3.7 Signs and symptoms: Irritation of nose and throat. Irritation of eyes and mucous membranes. Skin irritation, Unconsciousness, Corneal damage, Narcosis, 135
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Cyanosis (blue tissue condition, nails, lips, and/or skin). Decrease in motor functions. Behavioral changes, Edema, Liver enlargement. Jaundice, Conjunctivitis. Proteinuria, Defatting of the skin rash.
9.5.3.8 Potential environmental effects: Toxic to aquatic organisms. May cause longterm adverse effects in the aquatic environment.
9.5.4
Composition:
component Gasoline, straight-run, topping-plant Pentane Hexane (Other Isomers) Pentane Isomers Mixture n-Hexane Benzene Cyclohexane Cyclopentane Methyl cyclohexane n- Heptanes n-Butane Hydrogen sulfide 9.5.5
percentage 0 - 100 0 - 35 0 - 25 0 - 25 0 - 20 0-5 0-5 0-5 0-5 0-5 0-4 250
9.5.7
Accidental Release Measures:
9.5.7.1 Personal Precautions: Keep unnecessary personnel away. Local authorities should be advised if significant spills cannot be contained. Keep upwind. Keep out of low areas. Ventilate closed spaces before entering. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. See Section 8 of the MSDS for Personal Protective Equipment. 9.5.7.2 Environmental Precautions: Gasoline may contain oxygenated blend products (Ethanol, etc.) that are soluble in water and therefore precautions should be taken to protect surface and groundwater sources from contamination. If facility or operation has an "oil or hazardous substance contingency plan", activate its procedures. Stay upwind and away from spill. Wear appropriate protective equipment including respiratory protection as conditions warrant. Do not enter or stay in area unless monitoring indicates that it is safe to do so. Isolate hazard area and restrict entry to emergency crew. Extremely flammable. Review Fire Fighting Measures, Section 5, before proceeding with lean up. Keep all sources of ignition (flames, smoking, flares, etc.) and hot surfaces away from release. Contain spill in smallest possible area. Recover as much product as possible (e.g. by vacuuming). Stop leak if it can be done without risk. Use water spray to disperse vapors. Use compatible foam to minimize vapor generation as needed. Spilled material may be absorbed by an appropriate absorbent, and then handled in accordance with environmental regulations. Prevent spilled material from entering sewers, storm drains, other unauthorized treatment or drainage systems and natural waterways. Contact fire authorities and appropriate federal, state and local agencies. If 138
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spill of any amount is made into or upon navigable waters, the contiguous zones, or adjoining shorelines, contact the National Response Center 9.5.7.3 Methods For Containment: Eliminate all ignition sources (no smoking, flares, sparks, or flames in immediate area). Stop leak if you can do so without risk. This material is a water pollutant and should be prevented from contaminating soil or from entering sewage and drainage systems and bodies of water. Dike the spilled material, where this is possible. Prevent entry into waterways, sewers, basements or confined areas.
9.5.7.4 Methods For Cleaning Up: Use non-sparking tools and explosion-proof equipment. Small Spills: Absorb spill with vermiculite or other inert material, then place in a container for chemical waste. Clean surface thoroughly to remove residual contamination. This material and its container must be disposed of as hazardous waste. Large Spills: Use a noncombustible material like vermiculite, sand or earth to soak up the product and place into a container for later disposal. Prevent product from entering drains. Do not allow material to contaminate ground water system. Should not be released into the environment. 9.5.7.5 Other Information: Clean up in accordance with all applicable regulations. 9.5.8
Handling And Storage:
9.5.8.1 Handling: Wear personal protective equipment. Do not breathe dust/fume/gas/mist/vapors/spray. Avoid contact with eyes, skin, and clothing. Do not taste or swallow. Avoid prolonged exposure. Use only with adequate ventilation. Wash thoroughly after handling. The product is extremely flammable, and explosive vapor/air mixtures may be formed even at normal room temperatures. DO NOT handle, store or open near an open flame, sources of heat or sources of ignition. Protect material from direct sunlight. Take precautionary measures against static discharges. All equipment used when handling the product must be grounded. Use non-sparking tools and explosion139
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proof equipment. When using, do not eat, drink or smoke. Avoid release to the environment. 9.5.8.2 Storage : Flammable liquid storage. Do not handle or store near an open flame, heat or other sources of ignition. This material can accumulate static charge which may cause spark and become an ignition source. The pressure in sealed containers can increase under the influence of heat. Keep container tightly closed in a cool, well-ventilated place.
9.5.9
Exposure Controls/Personal Protection:
9.5.9.1 Appropriate Engineering Controls: Provide adequate ventilation, including appropriate local extraction, to ensure that the occupational exposure limit is not exceeded occupational Exposure Limit assigned. 9.5.9.1.2
Personal Protection
9.5.9.1.2.1 Eye/face protection: Goggles giving complete protection to eyes
9.5.9.1.2.2 Skin protection: Protective gloves
9.5.9.1.2.3 Respiratory protection: In case of insufficient ventilation, wear suitable respiratory equipment
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9.5.10 Physical And Chemical Properties Information on basic physical and chemical properties
Appearance: Color: Odour: Boiling Point (°C): Flash Point (°C):2
Liquid. Pale yellow. Hydrocarbon. < 35 1 10 200 (@ 20°C) 0.70-0.80 Negligible. 1.0-8.0 >250 1 mm2/s (@ 20°C) Vapor may create explosive Not oxidizing.
Other information
Conductivity:
15-35
9.5.11 Stability And Reactivity:
Reactivity Reacts with Chemical stability conditions. Possibility of hazardous reactions Conditions to avoid
Strong oxidizing agents. Stable under normal No information available. Keep away from heat, sources of 141
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ignition and direct sunlight.
9.5.12
Incompatible materials Hazardous Decomposition Product(s) fire.
Oxidizing agents. May give off toxic fumes in a Carbon monoxide, Carbon dioxide and various hydrocarbons
Toxicological Information:
Ingestion Inhalation
LD50 (oral/rat):>5000 mg/kg LC50 (inhalation/rat):>5.2 mg/l/4 h Skin Contact LD50 (dermal/rabbit):>2000 mg/kg Eye Contact No information available. Skin corrosion/irritation Irritating to skin. Serious eye damage/irritation May cause eye irritation. Respiratory or skin sensitization Negative. Mutagenicity May cause heritable genetic damage. Carcinogenicity May cause cancer. Reproductive toxicity Suspected of damaging fertility. Suspected of damaging the unborn child. STOT-single exposure Vapors may cause drowsiness and dizziness. STOT-repeated exposure Negative. Aspiration hazard Risk of aspiration .Aspiration of Liquid may cause pulmonary edema.
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Chapter 10
Instrumentation and Control
CHAPTER # 10 INSTRUMENTATION AND CONTROL
The important feature common to all process is that a process in never in a state of static equilibrium except for a very short period of time and process is a dynamic entity subject to continual upset or disturbance which' tend to drive it away from the desired state of equilibrium the process must then be manipulated upon or corrected to derive some disturbance bring about only transient effect in the process behavior. These passes away and the never occur again. Others may apply periodic or cycle forces which may make the process respond in a cyclic or periodic fashion. Most disturbances are completely random with respect to time a show no repetitive pattern. Thus their occurrence may be expected hut cannot be predicated at any particular time. If a process is to operate efficiently, disturbances in the process must be controlled. A process is designed for a particular objective or output and is then found. Sometimes by trial and error and sometimes by referring from the previous, experience that control of a particular variable associated with some stages of the process is necessary to achieve the desired efficiency. Each process will have associated with it number of variables which are independent of the process and/ or its operation and which are likely to change at random. Each such change will lead to changes in the dependent variables of the process one of which is selected as bring indicative of successfully operation. One of the input variable will be manipulated to cause further changes in the output variable will be manipulated to cause further
changes
in
the
output
variable
the
original
conditions, Process may controlled more precisely to give more uniform and higher quality products by the application of automatic control, often leading to higher profits additionally, process which response too rapidly to be controlled by human operators can be controlled automatically. Automatic control
is
also
beneficial in certain remote, hazardous or routine operations. After a period of experimentation, computers are now being used to operate automatic ally control
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processing systems, which may too large and too complex for effective direct human control. Since process profit is usually the most important benefit to obtained by applying automatic control. The quality of control and its cost should be compared
with
the economic
return
expected and
the
process
technical
objective. The economic return includes reduced operating costs, maintenance and of the specification product along with improved process operability and increased throughout. 10.1
COMPONENTS OF THE CONTROL SYSTEM:
10.1.1 Process: Any operation of series of operations that produce a desired final result is a process. In this discussion the process is the purification of natural 10.1.2 Measuring Means: As all the parts of the control system, measuring element, is perhaps the most important. If the measurements are not made properly the remainder of the system cannot operate satisfactorily. The measured variable is chosen to represent the desired condition in the process. 10.2
ANALYSIS OF MEASUREMENT:
10.2.1 Variables to be Measured: a. Pressure Measurement b. Temperature Measurement c. Flow Rate Measurement d. Level Measurement
10.2.2 Variables to be Recorded: Indicated temperature, composition, pressure etc.
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10.3
Instrumentation and Control
CONTROLLER:
The controller is the mechanism that responds to any error indicated by the error detecting mechanism. The output of the controller is some predetermined function of the error. There are three types of controllers. 1. Proportion action which moves the control valve indirect proportion to the magnitude of the error. 2. Integral action (reset) which moves the control valve based on the time integral of the error and the purpose of integral actions is to drive the process back to .its set point when it has been disturbed. 3. Ideal derivative action and its purpose are to anticipate where the process is heading by cooking at the time a rate of change of error. The final control
element receives the signal from the controller and by some
predetermined relationship changes the energy input to the process. 10.4
CHARACTERISTICS OF CONTROLLER:
In general the process controllers can be classified as a. Pneumatic controllers b. Electronic controllers c. Hydraulic controllers While dealing with the gases, the controller and the final control element may be pneumatically operated due to the following reasons. i.
The pneumatic controller is very rugged and almost free of maintenance. The maintenance men have not had sufficient training and background in electronics, so pneumatic equipment is simple.
ii.
Pneumatic controller appears to be safer in a potentially explosive atmosphere which is often present in the industry.
iii.
Transmissions distances are short pneumatic and electronic transmissions system are generally equal up to about 200 to 300 feet. Above this distance electronic system beings to offer savings.
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10.5
Instrumentation and Control
MODES OF CONTROL:
The various types of control are called modes, and they determine type of response obtained. In other words these describe the action of controller that is the relationship of output of output signal to the input or error signal. It must be noted that is error that achieve the controller. The four basic mode of control are: 1. On-off control 2. Integral control 3. Proportional control 4. Rate or derivative control In industry purely integral, proportional or derivative modes seldom occur alone in the control system. The on-off controller is the controller with very high gain. In this case the error signal at once off the valve or any other parameter upon which it sites or completely sets system.
10.6
ALARMS AND SAFETY TRIPS:
Alarms are used to alert operators of serious and potentially hazardous, deviations in process conditions, key instruments are fitted with switches and relays to operate audible and visual alarms on the control panels. The basic components of an automatic trip system are 1. A sensor to monitor the control variable and provide and output signal when a preset value is exceeded (the instrument). 2. A link to transfer the signal to the activator, usually consisting of a system of pneumatic or electric relays. 3. An activator to carry out the required action close or open a valve, switch off a motor. 10.7
CONTROL LOOPS:
For instrumentation and control of different sections and equipments of plants, following control loops are most often used.
1. Feed backward control loop 146
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2. Feed forward control loop 3. Ratio control loop 4. Auctioneering control loop 5. Split range control loop 6. Cascade control loop Here is given a short outline of these control schemes, so that to justify our selection of a control loop for specified equipment. 10.8
FEED BACK CONTROL LOOP:
A method of control in which a measured value of a process variable is compared with the desired value of the process variable and any necessary action is taken. Feedback control is considered as the basic control loops system. Its disadvantage lies in its operational procedure. For example if a certain quantity is entering in a process, then a monitor will be there at the process to note its value. Any changes from the set point will be sent to the final control element through the controller so that to adjust the incoming quantity according to desired value (set point). But in fact change has already occurred and only corrective action can be taken while using feedback-control system. 10.9
FEED FORWARD CONTROL LOOP:
A method of control in which the value of a disturbance is measured, and action is taken to prevent the disturbance by changing the value of a process variable. This is a control method designed to prevent errors from occurring in a process variable. This control system is better than feedback control because it anticipates the change in the process variable before it enters the process takes the preventive action. While in feedback enter system action is taken after the change has occurred. 10.10 RATIO CONTROL: A control loop in which, the controlling element maintains a predetermined ratio of one variable to another. Usually this control loop is attached to such a system where two different streams enter a vessel for reaction that may be of any kind. To maintain the stoichiometric quantities of different streams this loop is used so that to ensure proper process going on in the process vessel.
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10.11 AUCTIONEERING CONTROL LOOP: This type of control loop is normally used for a huge vessel where, readings of a single variable may be different at different locations. This type of control loop ensures safe operation because it employs all the readings of different locations simultaneously, and compares them with the set point, if any of those readings is deviating from the set point then the controller sends appropriate signal to final control element. 10.12 SPLIT RANGE LOOP: In this loop controller is per set with different values corresponding to different action to be taken at different conditions. The advantage of this loop is to maintain the proper conditions and avoid abnormalities at very differential levels. 10.13 CASCADE CONTROL LOOP: This is a control in which two or more control loops are arranged so that the output of, one controlling element adjusts the set point of another controlling element. This control loop is used where proper and quick control is difficult by simple feed forward or feed backward control. Normally first loop is a feedback control loop. We have selected a cascade control loop for our heat exchanger in order to get quick on proper control. 10.14 INTERLOCKS: Where it is necessary to follow a fixed sequence of operations for example, during a plant start-up and shut-down, or in batch operations. Interlocks are includes to prevent operators departing from the required sequence. They may be incorporated in the control system design, as pneumatic or electric relays or may be mechanical interlocks. 10.15 CONTROL OF HEAT EXCHANGER: 10.15.1
The Normal Way:
The normal method of controlling a heat exchanger is to measure exit temperature of process fluid and adjust input of heating or cooling medium to hold the desired temperature. 148
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To stabilize this feedback control, in almost all cases the control must have a wide proportional band (i.e., wide range of exit temperature change operates the control valve through full stroke). The proportional band is determined by gain of other components in the control loop by process considerations. Since heat-exchanger control require a wide proportional band for stabilization, reset response (rate of change of heating medium How proportional to exit temperature. deviation from controller set point is normally required to correct for offset in the controlled variable (temperature). It there are process load change and reset response can be eliminated in cases where disturbance such as heating fluid header pressure, product flow rate or inlet temperature changes have small effects relative to desired tolerance on the controlled variable. When throughout to a heat exchanger is changed rapidly a short-term error in control temperature results. The magnitude and duration of this error can normally be reduced by a factor of two by adding derivative response to the control mechanism and adjusting it properly. In derivative responses, heating fluid flow rate is proportional to rate or change of temperature derivation from the set point. 10.15.2
A Pressure Cascade Control:
A pressure cascade control system cascades output of a standard three action temperature controller into the set point of a pressure controller. It achieves a more rapid recovery to process load disturbances in a shell-and-tube exchanger than can be obtained without the pressure controller. Heating fluid to the heater is regulated by the pressure controller which is normally provided with proportional and reset responses. Load change is rapidly sensed by a change is shell pressure which is compensated for by the pressure controller. The temperature control system senses the residual error and resets the pressure control set point.
10.15.3
Bypass Improves Control of Slow-Response Exchanger:
In certain cascade, the time response characteristic of heat exchanger is too slow to hold temperature deviations resulting from load changes within desired tolerances. In 149
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some of these cases, the transient characteristic of the heat exchanger can be circumvented by by- passing the heater with a parallel line and bleeding cold process fluid with hot fluid from the heater. In the by-pass system care must be taken in sizing valves to obtain the-desired flow sprit with adequate flow versus steam travel characteristics. Thermal elements response time is particularly important since this tie constant is a major factor influencing performance of the system. 10.15.4
Flow Controllers:
These are used to control tin-feed rate into a process unit Orifice plates are by far the most type of How-rate sensor. Normally orifice plates arc designed to give pressure drops in the range of 20 to 200 inch of water Venture tubes amend turbine meter are also used. 10.15.5
Temperature controller:
Thermocouples are the most commonly used temperature sensing device. The two dissimilar wires produce a millivolt emf that varies with the ―hot- functions‖ temperature. Iron constant to thermocouples are commonly used over the 0 to 1300 F. temperature range. 10.15.6
Pressure Controller:
Bourdon tubes, bellows and diaphragms are used to sense pressure and differential pressure. For example, in mechanical system the process pressure force is balanced by the movement of a spring. The spring positing can be related to process pressure. 10.15.7
Level Indicator:
Liquid levels are detected in a variety of ways. The three common are 1. The following the position of a float that is lighter than the fluid. 2. Measuring one apparent-weight of a heavy cylinder as it is buoyed up more or less by the liquid (they are called displacement meters). 3. Measuring the difference in static pressure between two fixed elevations, one in the vapour above the liquid and the other under the liquid surface. The differential pressure between the two level taps is directly related to the liquid level in the vessel.
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10.15.8
Instrumentation and Control
Transmitter:
The transmitter is the interface between the process and its control system. The Job of the transmitter is to convert the sensor signal (millivolts, mechanical movement, pressure difference etc.) into a control signal 3 to 15 psig air pressure signal, 1 to 5 10 to 50 milli ampere electrical signal etc.
10.15.9
Control Valves:
The interface with the process at the other end of the control loop is made by the final control element in an automatic control valves control the flow of heating fluid the open or close and orifice opening as the system is raised or lowered.
151
REFERENCES
1.
M.A Fahim, Fundamentals of Petroleum Refining, 1st edition, Elsevier ,2010
2.
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Professional Publishers, 2002. 6.
McKetta, J.J., ―Encyclopedia of chemical Processing and Design‖, Executive ed, vol. 1, Marcel Dekker Inc, New York, 1976.
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Peters, M.S. and Timmerhaus ,K.D., ―Plant Design and Economics for Chemical Engineering ―, 5th ed, McGraw Hill, 1991.
9.
Rase, H.F., ―Fixed Bed Reactor Design and Diagnostics, Butterworth Publishers, 1990.
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Frank L., Evans Jr. ―Equipment Design Hand Book For Refineries & Chemical Plants‖ Vol 2, 2nd Ed., 1980,
11.
Peacock, D.G.,‖ Coulson & Richardson‘s Chemical engineering‖, 3rd ed,vol,Butterworth Heinenann, 1994.
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Kern D.Q., ―Process Heat Transfer‖, McGraw H ill Inc.,2000.
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153
APPENDICES
A
Components Properties
B
Thermodynamic Properties
C
Equilibrium Constants
D
Graphs used in the designing of Compressor, pump, heat exchanger and Distillation column
154
APPENDIX A
Components
Hydrogen Methane Ethane Propane n-Butane n-Pentane n-Hexane n-Heptane i-Butane i-Pentane 2-Mpentane 3-Mpentane 22-Mbutane 23-Mbutane 2-Mhexane 3-Mhexane 22-Mpentane 23-Mpentane 24-Mpentane 33-Mpentane 3-Epentane Benzene Toluene Cyclopentane Mcyclopentan Cyclohexane Ecyclopentan Mcyclohexane 223-Mbutane H2O CCl4
Boiling Temperature C -252.595 -161.525 -88.6 -42.102 -0.50199 36.059 68.73 98.429 -11.73 27.878 60.261 63.27 49.731 57.977 90.049 91.847 79.191 89.778 80.493 86.059 93.472 80.089 110.649 49.248 71.809 80.73 103.467 100.929 80.876 99.998 76.748
155
Mol Wt
2.016 16.0429 30.0699 44.097 58.124 72.151 86.1779 100.205 58.124 72.151 86.1779 86.1779 86.1779 86.1779 100.205 100.205 100.205 100.205 100.205 100.205 100.205 78.11 92.1408 70.135 84.1619 84.16 98.189 98.189 100.205 18.0151 153.822
Critical Pressure Kpa 1315.5 4640.68 4883.85 4256.66 3796.62 3375.12 3031.62 2736.78 3647.62 3333.59 3010.36 3123.84 3880.62 3126.87 2733.62 2813.79 2773.26 2908.02 2736.78 2945.51 2890.8 4924.39 4100.04 4508.95 3789.55 4053 3397.62 3475.37 2953.62 22120 4559.99
Critical Temp C -239.71 -82.451 32.278 96.748 152.049 196.45 234.748 267.008 134.946 187.248 224.347 231.299 231.299 226.83 257.219 262.1 247.35 264.198 246.639 263.248 267.49 288.948 318.649 238.45 259.55 280.05 296.37 298.948 258.019 374.149 283.25
Heat of Combustion kJ/Kmol -241942 -802703 -1.43E+06 -2.04E+06 -2.66E+06 -3.27E+06 -3.89E+06 -4.50E+06 -2.65E+06 -3.27E+06 -3.85E+06 -3.88E+06 -3.87E+06 -3.88E+06 -4.50E+06 -4.50E+06 -4.49E+06 -4.49E+06 -4.49E+06 -4.49E+06 -4.50E+06 -3.17E+06 -3.77E+06 -3.10E+06 -3.71E+06 -3.69E+06 -4.32E+06 -4.29E+06 -4.49E+06 -258069
Heat of Formation kJ/Kmol 0 -74900 -84738 -103890 -126190 -146490 -167290 -187890 -134590 -154590 -174390 -171690 -185690 -177890 -195090 -192390 -206290 -199390 -202090 -201690 -189790 82977 50029 -77288 -106790 -123190 -127190 -154890 -204890 -241814 -100488
MON
100.789 97.1 89.6 62.6 26 0 97.6 90.3 73.5 74.3 93.4 94.3 46.4 55.8 95.6 88.5 83.8 86.6 69.3 101 103.524 84.9 80 77.2 61.2 71.1 101
156
RON
130 120 111.378 112.135 93.8 61.7 24.8 0 101.426 92.3 73.4 74.5 91.8 100 42.4 52 92.8 91.1 83.1 80.8 65 106 120.083 101.426 91.3 83 67.2 74.8 100
Flash point
-40.15 -21.15 -4.15 -56.15 -35.15 -32.15 -48.15 -29.15 -23.15 -4.15 -15.15 -15.15 -12.15 -19.15 -12.15 -11.15 3.85 -40.15 -27.15 -20.15 -4.15 -6.15 -24.15
Freez point
-259.25 -182.75 -182.75 -187.65 -138.15 -130.15 -95.15 -90.15 -159.15 -160.15 -153.15 -163.15 -99.15 -128.15 -118.15 -119.15 -124.15 -119.15 -134.15 -118.15 5.85 -95.15 -94.15 -142.15 6.85 -138.15 -126.15 -24.15
APPENDIX B
Antoine Equation Tmin
Tmax
ln(P) = a + b/(T + c) + d*ln(T) + e*T^f Default Q
a
b
c
d
e
f
Hydrogen Methane Ethane
13 91 133
32 190.4 305.4
101.3 101.3 101.3
9.183 31.35 44.01
-107.9 -1308 -2569
0 0 0
0.1641 -3.261 -4.976
6.02E-04 2.94E-05 1.46E-05
2 2 2
Propane
145
369.8
101.3
52.38
-3491
0
-6.109
1.12E-05
2
n-Butane i-Butane n-Pentane i-Pentane 22-Mpropane n-Hexane 2-Mpentane 3-Mpentane 22-Mbutane 23-Mbutane n-Heptane 2-Mhexane 3-Mhexane 22-Mpentane 23-Mpentane 24-Mpentane 33-Mpentane 3-Epentane 223-Mbutane Benzene Toluene Cyclopentane
170 165 195 220 260 220 230 235 225 235 230 230 235 225 230 225 225 265 250 213 178.2 288
425.2 408.1 469.6 460.4 433.8 507.5 497.5 504.4 488.8 500 540.2 530.4 535.3 520.5 537.3 519.8 536.4 540.6 531.2 552 591.8 511.6
101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3 101.3
66.94 58.78 63.33 66.76 69.98 70.43 72.46 70.35 56.69 67.02 78.33 75.79 74.79 70.43 70.99 71.35 77.56 78.75 69.23 169.7 76.45 51.84
-4604 -4137 -5118 -5059 -4845 -6056 -5929 -5909 -5087 -5625 -6947 -6688 -6650 -6198 -6430 -6255 -6450 -6816 -6100 -1.03E+04 -6995 -4915
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
-8.255 -7.017 -7.483 -8.089 -8.701 -8.379 -8.765 -8.419 -6.384 -7.959 -9.449 -9.1 -8.95 -8.363 -8.391 -8.497 -9.517 -9.568 -8.213 -23.59 -9.164 -5.623
1.16E-05 1.04E-05 7.77E-06 9.25E-06 1.11E-05 6.62E-06 7.62E-06 7.06E-06 5.41E-06 6.96E-06 6.48E-06 6.44E-06 6.30E-06 6.29E-06 5.88E-06 6.39E-06 7.89E-06 6.93E-06 6.30E-06 2.09E-05 6.23E-06 4.80E-06
2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2
Mcyclopentan Cyclohexane Cyclopentane Mcyclohexane H2O CCl4
288 293 376.6 298 275 250
532.7 553.2 569.5 572.1 647.3 556.4
101.3 101.3 101.3 101.3 101.3 101.3
71.34 70.98 98.91 72.24 65.93 74.22
-6030 -6187 -7885 -6555 -7228 -6240
0 0 0 0 0 0
-8.572 -8.465 -12.58 -8.597 -7.177 -8.987
7.17E-06 6.45E-06 8.90E-06 5.97E-06 4.03E-06 7.19E-06
2 2 2 2 2 2
157
Gibbs Free Energy
G = a + b*T + c*T^2 + d*T^3 + e*T^4
a Hydrogen Methane Ethane Propane n-Butane i-Butane n-Pentane i-Pentane 22-Mpropane n-Hexane 2-Mpentane 3-Mpentane 22-Mbutane 23-Mbutane n-Heptane 2-Mhexane 3-Mhexane 22-Mpentane 23-Mpentane 24-Mpentane 33-Mpentane 3-Epentane 223-Mbutane Benzene Toluene Cyclopentane Cyclopentane Cyclohexane Ecyclopentane Mcyclohexane H2O CCl4
0 -7.72E+04 -8.58E+04 -1.06E+05 -1.28E+05 -1.37E+05 -1.49E+05 -1.57E+05 -1.69E+05 -1.71E+05 -1.78E+05 -1.75E+05 -1.89E+05 -1.81E+05 -1.92E+05 -1.99E+05 -1.96E+05 -2.10E+05 -2.03E+05 -2.06E+05 -2.05E+05 -1.93E+05 -2.09E+05 8.15E+04 4.78E+04 -8.05E+04 -1.10E+05 -1.28E+05 -1.31E+05 -1.60E+05 -2.41E+05 -1.01E+05
b
c
d
e
0 0 87.74 8.60E-03 168.6 2.69E-02 264.8 3.25E-02 360.5 3.83E-02 376.4 3.75E-02 457.5 4.44E-02 464 4.34E-02 502.8 3.96E-02 554.2 5.03E-02 563 4.83E-02 562.7 5.04E-02 586.5 4.76E-02 577.8 4.97E-02 650.5 5.64E-02 658.4 5.65E-02 654.3 5.65E-02 685.6 5.64E-02 664.6 5.63E-02 681.9 5.63E-02 678.9 5.63E-02 666.9 5.65E-02 698.1 5.26E-02 152.8 2.65E-02 238.3 3.19E-02 384.5 4.52E-02 474 4.91E-02 520.3 4.47E-02 571.4 5.48E-02 612.5 4.63E-02 43.41 4.96E-03 145.6 -8.68E-03
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
158
Enthalpy
H = a + b*T + c*T^2 + d*T^3 + e*T^4 a
Hydrogen Methane Ethane Propane n-Butane i-Butane n-Pentane i-Pentane 22-Mpropane n-Hexane 2-Mpentane 3-Mpentane 22-Mbutane 23-Mbutane n-Heptane 2-Mhexane 3-Mhexane 22-Mpentane 23-Mpentane 24-Mpentane 33-Mpentane 3-Epentane 223-Mbutane Benzene Toluene Cyclopentane Mcyclopentan eCyclohexane Ecyclopentane Mcyclohexane H2O
-49.68 -12.98 -1.768 39.49 67.72 30.9 63.2 64.25 0 74.51 111.5 83.82 0 0 71.41 47.74 1.96E-08 77.69 80.01 75.92 82.69 78.61 86.02 84.47 74.16 1.56E-08 127.2 4.56E-09 64.92 107.6 -5.73 0
b
c
13.84 3.00E-04 2.365 -2.13E-03 1.143 -3.24E-04 0.395 2.11E-03 8.54E-03 3.28E-03 0.1533 2.64E-03 -1.17E-02 3.32E-03 -0.1318 3.54E-03 -2.20E-02 3.29E-03 -9.67E-02 3.48E-03 -0.6057 4.92E-03 -0.1695 3.68E-03 -0.193 3.65E-03 -0.1695 3.57E-03 -9.69E-02 3.47E-03 -0.125 3.60E-03 -5.61E-02 3.38E-03 0.2155 2.82E-03 0.158 2.83E-03 0.2227 2.82E-03 0.1556 2.83E-03 0.1546 2.83E-03 0.1548 2.83E-03 -0.5133 3.25E-03 -0.4231 3.18E-03 -0.7645 3.87E-03 -0.6841 4.01E-03 -0.6481 3.63E-03 -0.677 4.22E-03 -0.7046 4.10E-03 1.915 -3.96E-04 0.2649 6.67E-04
159
d 3.46E-07 5.66E-06 4.24E-06 3.97E-07 -1.11E-06 7.27E-08 -1.17E-06 -1.33E-06 -8.71E-07 -1.32E-06 -3.02E-06 -1.56E-06 -2.42E-06 -2.35E-06 -1.33E-06 -1.28E-06 -1.21E-06 -6.68E-07 -6.76E-07 -6.68E-07 -6.75E-07 -6.77E-07 -6.74E-07 -1.54E-06 -1.44E-06 -1.44E-06 -1.68E-06 -9.99E-07 -2.12E-06 -1.53E-06 8.76E-07 -4.92E-07
e -9.71E-11 -3.73E-09 -3.39E-09 -6.67E-10 1.77E-10 -7.28E-10 2.00E-10 2.51E-10 -9.07E-11 2.52E-10 1.07E-09 3.54E-10 6.44E-10 6.41E-10 2.56E-10 9.86E-11 1.85E-10 0 0 0 0 0 0 3.65E-10 3.27E-10 2.31E-10 3.58E-10 3.92E-11 7.00E-10 1.83E-10 -4.95E-10 1.44E-10
Heat Capacity (Gas) CpG CpG = a + b*T + c*T^2 + d*T^3 a Hydrogen Methane Ethane Propane n-Butane n-Pentane n-Hexane n-Heptane i-Butane i-Pentane 2-Mpentane 3-Mpentane 22-Mbutane 23-Mbutane 2-Mhexane 3-Mhexane 22-Mpentane 23-Mpentane 24-Mpentane 33-Mpentane 3-Epentane Benzene Toluene Cyclopentane Mcyclopentane Cyclohexane Ecyclopentane Mcyclohexane 223-Mbutane
27.143 19.251 5.409 -4.224 9.487 -3.626 -4.413 -5.146 -1.39 -9.525 -10.57 -2.386 -16.634 -14.608 -39.389 -7.046 -50.099 -7.046 -7.046 -7.046 -7.046 -33.917 -24.355 -53.625 -50.108 -54.541 -61.919 -55.312 -22.944
b c 9.27E-03 -1.38E-05 5.21E-02 1.20E-05 1.78E-01 -6.94E-05 3.06E-01 -1.59E-04 3.31E-01 -1.11E-04 4.87E-01 -2.58E-04 5.82E-01 -3.119E-04 6.76E-01 -3.65E-04 3.85E-01 -1.85E-04 5.07E-01 -2.73E-04 6.18E-01 -3.57E-04 5.69E-01 -2.87E-04 6.29E-01 -3.48E-04 6.15E-01 -3.38E-04 8.64E-01 -6.29E-04 6.84E-01 -3.73E-04 8.96E-01 -6.36E-04 7.05E-02 -3.73E-04 6.84E-01 -3.73E-04 6.84E-01 -3.73E-04 6.84E-01 -3.73E-04 4.74E-01 -3.02E-04 5.12E-01 -2.77E-04 5.43E-01 -3.03E-04 6.38E-01 -3.64E-04 6.11E-01 -2.52E-04 7.84E-01 -4.44E-04 7.51E-01 -4.40E-04 7.52E-01 -4.42E-04
160
d 7.65E-09 -1.13E-08 8.71E-09 3.21E-08 -2.82E-09 5.30E-08 6.49E-08 7.66E-08 2.90E-08 5.72E-08 8.08E-08 5.03E-08 6.85E-08 6.82E-08 1.84E-07 7.83E-08 1.74E-07 7.83E-08 7.83E-08 7.83E-08 7.83E-08 7.13E-08 4.91E-08 6.49E-08 8.01E-08 1.32E-08 9.37E-08 1.00E-07 1.00E-07
Heat Capacity (Liquid) CpL CpL = a + b*T + c*T^2 + d*T^3 +e*T^4 a
Hydrogen Methane Ethane Propane n-Butane n-Pentane n-Hexane n-Heptane i-Butane i-Pentane 2-Mpentane 3-Mpentane 22-Mbutane 23-Mbutane 2-Mhexane 3-Mhexane 22-Mpentane 23-Mpentane 24-Mpentane 33-Mpentane 3-Epentane Benzene Toluene Cyclopentane Mcyclopentane Cyclohexane Ecyclopentane Mcyclohexane 223-Mbutane H2O
15.84 370.4 143.4 124.03 319.19 164.2199 198.2 218.5 172.37 108.3 142.22 140.49 125.45 129.45 174.01 157.94 133.57 146.42 133.5 156.03 148.02 129.44 140.1399 122.53 155.92 -220.6 178.52 131.34 88.446 276.37
b
c
-0.8189 -11.3 -2.118 -1.0717 -3.5845 -0.3209 -0.3866 -0.2968 -1.7839 0.146 -4.78E-02 -3.48E-02 3.54E-02 1.85E-02 -0.10578 -4.40E-03 0.1093999 5.92E-02 0.1278 -5.28E-02 6.39E-02 -0.1695 -0.1523 -0.4038 -0.4899999 3.1183 -0.51835 -6.31E-02 0.40272 -2.0901
4.87E-02 0.1483 2.15E-02 1.01E-02 2.26E-02 1.11E-03 1.26E-03 1.06E-03 1.48E-02 -2.92E-04 7.39E-04 6.81E-04 5.96E-04 6.08E-04 9.05E-04 7.10E-04 6.19E-04 6.04E-04 5.92E-04 8.34E-04 5.91E-04 6.48E-04 6.95E-04 1.73E-03 2.14E-03 -9.42E-03 2.33E-03 8.13E-04 5.62E-05 8.13E-03
161
d
e
0 -8.55E-04 -9.35E-05 -3.84E-05 -6.07E-05
0 1.86E-06 1.52E-07 5.57E-08 6.28E-08
-4.79E-05 1.51E-06
5.81E-08
-2.72E-17
3.61E-20
3.98E-20 -1.10E-06 -1.56E-06 1.07E-05 -1.68E-06
-3.47E-23
-1.41E-05
9.37E-09
9.34E-22 1.17E-22
Temerature Temerature K C 373 100 383 110 393 120 403 130 413 140 423 150 433 160 443 170 453 180 463 190 473 200
X% 69.74414 68.24566 66.78855 65.37429 64.00378 62.67745 61.39534 60.15713 58.96228 57.80999 56.69932
X 0.697441 0.682457 0.667886 0.653743 0.640038 0.626775 0.613953 0.601571 0.589623 0.5781 0.566993
K 2.305145 2.149176 2.01101 1.888027 1.77807 1.679346 1.590361 1.50986 1.436782 1.370229 1.309433
ln K 0.835144 0.765084 0.698637 0.635533 0.575528 0.518404 0.463961 0.412017 0.362406 0.314978 0.269594
∆G -2.59E+03 -2.44E+03 -2.28E+03 -2.13E+03 -1.98E+03 -1.82E+03 -1.67E+03 -1.52E+03 -1.36E+03 -1.21E+03 -1.06E+03
G iC4 8.82E+03 1.29E+04 1.69E+04 2.10E+04 2.51E+04 2.91E+04 3.32E+04 3.73E+04 4.14E+04 4.55E+04 4.96E+04
c 3.75E-02 3.75E-02 3.75E-02 3.75E-02 3.75E-02 3.75E-02 3.75E-02 3.75E-02 3.75E-02 3.75E-02 3.75E-02
b 3.76E+02 3.76E+02 3.76E+02 3.76E+02 3.76E+02 3.76E+02 3.76E+02 3.76E+02 3.76E+02 3.76E+02 3.76E+02
a -1.37E+05 -1.37E+05 -1.37E+05 -1.37E+05 -1.37E+05 -1.37E+05 -1.37E+05 -1.37E+05 -1.37E+05 -1.37E+05 -1.37E+05
G nC4 1.14E+04 1.53E+04 1.92E+04 2.31E+04 2.70E+04 3.10E+04 3.49E+04 3.88E+04 4.28E+04 4.67E+04 5.07E+04
c 3.83E-02 3.83E-02 3.83E-02 3.83E-02 3.83E-02 3.83E-02 3.83E-02 3.83E-02 3.83E-02 3.83E-02 3.83E-02
b
3.60E+02 3.60E+02 3.60E+02 3.60E+02 3.60E+02 3.60E+02 3.60E+02 3.60E+02 3.60E+02 3.60E+02 3.60E+02
a
-1.28E+05 -1.28E+05 -1.28E+05 -1.28E+05 -1.28E+05 -1.28E+05 -1.28E+05 -1.28E+05 -1.28E+05 -1.28E+05 -1.28E+05
iC4/nC4
APPENDIX C
162
iC5/nC5 Temperature Temperature K C 100 373 110 383 120 393 130 403 140 413 150 423 160 433 170 443 180 453 190 463 200 473
a -1.49E+05 -1.49E+05 -1.49E+05 -1.49E+05 -1.49E+05 -1.49E+05 -1.49E+05 -1.49E+05 -1.49E+05 -1.49E+05 -1.49E+05
b 4.57E+02 4.57E+02 4.57E+02 4.57E+02 4.57E+02 4.57E+02 4.57E+02 4.57E+02 4.57E+02 4.57E+02 4.57E+02
c 4.44E-02 4.44E-02 4.44E-02 4.44E-02 4.44E-02 4.44E-02 4.44E-02 4.44E-02 4.44E-02 4.44E-02 4.44E-02
G nC5 2.77E+04 3.26E+04 3.75E+04 4.24E+04 4.74E+04 5.23E+04 5.73E+04 6.22E+04 6.72E+04 7.22E+04 7.72E+04
a -1.57E+05 -1.57E+05 -1.57E+05 -1.57E+05 -1.57E+05 -1.57E+05 -1.57E+05 -1.57E+05 -1.57E+05 -1.57E+05 -1.57E+05
163
b 4.64E+02 4.64E+02 4.64E+02 4.64E+02 4.64E+02 4.64E+02 4.64E+02 4.64E+02 4.64E+02 4.64E+02 4.64E+02
c 4.34E-02 4.34E-02 4.34E-02 4.34E-02 4.34E-02 4.34E-02 4.34E-02 4.34E-02 4.34E-02 4.34E-02 4.34E-02
G iC5 2.17E+04 2.66E+04 3.16E+04 3.66E+04 4.16E+04 4.66E+04 5.16E+04 5.66E+04 6.17E+04 6.67E+04 7.17E+04
∆G -6.01E+03 -5.95E+03 -5.90E+03 -5.84E+03 -5.78E+03 -5.73E+03 -5.67E+03 -5.61E+03 -5.56E+03 -5.50E+03 -5.45E+03
ln K
K
X
X%
1.938594 1.869926 1.804815 1.742994 1.684226 1.628294 1.575001 1.524169 1.475634 1.429249 1.384875
6.948976 6.487819 6.078845 5.714428 5.38828 5.095175 4.830747 4.591326 4.373809 4.17556 3.994328
0.874198 0.86645 0.858734 0.851067 0.843463 0.835936 0.828495 0.821152 0.813912 0.806784 0.799773
87.41976 86.64498 85.8734 85.1067 84.34633 83.59358 82.84954 82.11515 81.39123 80.67842 79.97728
2MP/nC6 Temperature Temperature C K 100 373 110 383 120 393 130 403 140 413 150 423 160 433 170 443 180 453 190 463 200 473
a -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05
b 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02
c 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02
G nC6 4.36E+04 4.96E+04 5.55E+04 6.15E+04 6.75E+04 7.35E+04 7.94E+04 8.55E+04 9.15E+04 9.75E+04 1.04E+05
a
b
-1.78E+05 -1.78E+05 -1.78E+05 -1.78E+05 -1.78E+05 -1.78E+05 -1.78E+05 -1.78E+05 -1.78E+05 -1.78E+05 -1.78E+05
5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02
c 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02
G 2MP 3.91E+04 4.51E+04 5.11E+04 5.71E+04 6.31E+04 6.91E+04 7.52E+04 8.12E+04 8.73E+04 9.34E+04 9.95E+04
∆G -4.57E+03 -4.52E+03 -4.47E+03 -4.42E+03 -4.37E+03 -4.32E+03 -4.27E+03 -4.22E+03 -4.17E+03 -4.13E+03 -4.08E+03
ln K
K
X
X%
1.473963 1.418852 1.366833 1.317678 1.271178 1.227145 1.185408 1.145811 1.108213 1.072484 1.038506
4.366507 4.132373 3.922909 3.73474 3.565051 3.411476 3.272021 3.144991 3.028941 2.922631 2.824993
0.813659 0.805158 0.796868 0.788795 0.780944 0.773319 0.765919 0.758745 0.751796 0.745069 0.738562
81.36591 80.51583 79.68681 78.87952 78.09444 77.33185 76.59188 75.8745 75.17958 74.5069 73.85616
ln K
K
X
X%
0.603146 0.571776 0.542291 0.514551 0.488429 0.463811 0.440591 0.418676 0.39798 0.378422 0.359931
1.827861 1.771411 1.719943 1.672888 1.629755 1.590122 1.553626 1.519949 1.488814 1.459979 1.43323
0.646376 0.639173 0.632345 0.625873 0.619736 0.613918 0.6084 0.603167 0.598202 0.593492 0.589024
64.63758 63.91729 63.23453 62.58728 61.97364 61.39178 60.84 60.31665 59.82021 59.34924 58.90237
3MP/nC6 Temperature Temperature C K 100 373 110 383 120 393 130 403 140 413 150 423 160 433 170 443 180 453 190 463 200 473
a -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05
b 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02
c 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02
G nC6 4.36E+04 4.96E+04 5.55E+04 6.15E+04 6.75E+04 7.35E+04 7.94E+04 8.55E+04 9.15E+04 9.75E+04 1.04E+05
a
b
-1.75E+05 -1.75E+05 -1.75E+05 -1.75E+05 -1.75E+05 -1.75E+05 -1.75E+05 -1.75E+05 -1.75E+05 -1.75E+05 -1.75E+05
164
5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02 5.63E+02
c 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02 4.83E-02
G 3MP 4.18E+04 4.78E+04 5.38E+04 5.98E+04 6.58E+04 7.18E+04 7.79E+04 8.39E+04 9.00E+04 9.60E+04 1.02E+05
∆G -1.87E+03 -1.82E+03 -1.77E+03 -1.72E+03 -1.68E+03 -1.63E+03 -1.59E+03 -1.54E+03 -1.50E+03 -1.46E+03 -1.42E+03
22DMB/nC6 Temperature Temperature C K 100 373 110 383 120 393 130 403 140 413 150 423 160 433 170 443 180 453 190 463 200 473
a
b
c
G nC6
a
b
c
G 22DMB
∆G
ln K
K
X
X%
-1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05
5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02
5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02
4.36E+04 4.96E+04 5.55E+04 6.15E+04 6.75E+04 7.35E+04 7.94E+04 8.55E+04 9.15E+04 9.75E+04 1.04E+05
-1.89E+05 -1.89E+05 -1.89E+05 -1.89E+05 -1.89E+05 -1.89E+05 -1.89E+05 -1.89E+05 -1.89E+05 -1.89E+05 -1.89E+05
5.86E+02 5.86E+02 5.86E+02 5.86E+02 5.86E+02 5.86E+02 5.86E+02 5.86E+02 5.86E+02 5.86E+02 5.86E+02
4.76E-02 4.76E-02 4.76E-02 4.76E-02 4.76E-02 4.76E-02 4.76E-02 4.76E-02 4.76E-02 4.76E-02 4.76E-02
3.62E+04 4.24E+04 4.86E+04 5.49E+04 6.11E+04 6.74E+04 7.37E+04 7.99E+04 8.62E+04 9.25E+04 9.88E+04
-7.47E+03 -7.18E+03 -6.90E+03 -6.62E+03 -6.34E+03 -6.07E+03 -5.79E+03 -5.51E+03 -5.24E+03 -4.96E+03 -4.69E+03
2.407693 2.256172 2.112692 1.976655 1.847522 1.724801 1.608049 1.496861 1.39087 1.289738 1.193157
11.10831 9.546472 8.270474 7.218559 6.344076 5.611403 4.993059 4.467645 4.018345 3.631835 3.297476
0.917412 0.905182 0.892131 0.878324 0.863836 0.848746 0.83314 0.817106 0.800731 0.784103 0.767305
91.74121 90.51816 89.21307 87.83242 86.38358 84.87462 83.31403 81.71059 80.07311 78.41028 76.73053
23DMB/nC6 Temperature Temperature C K 100 373 110 383 120 393 130 403 140 413 150 423 160 433 170 443 180 453 190 463 200 473
a
b
c
G nC6
a
b
c
G 23DMB
∆G
ln K
K
X
X%
-1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05 -1.70E+05
5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02 5.54E+02
5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02 5.30E-02
4.36E+04 4.96E+04 5.55E+04 6.15E+04 6.75E+04 7.35E+04 7.94E+04 8.55E+04 9.15E+04 9.75E+04 1.04E+05
-1.81E+05 -1.81E+05 -1.81E+05 -1.81E+05 -1.81E+05 -1.81E+05 -1.81E+05 -1.81E+05 -1.81E+05 -1.81E+05 -1.81E+05
5.78E+02 5.78E+02 5.78E+02 5.78E+02 5.78E+02 5.78E+02 5.78E+02 5.78E+02 5.78E+02 5.78E+02 5.78E+02
4.97E-02 4.97E-02 4.97E-02 4.97E-02 4.97E-02 4.97E-02 4.97E-02 4.97E-02 4.97E-02 4.97E-02 4.97E-02
4.11E+04 4.73E+04 5.35E+04 5.96E+04 6.58E+04 7.20E+04 7.82E+04 8.44E+04 9.07E+04 9.69E+04 1.03E+05
-2.48E+03 -2.27E+03 -2.06E+03 -1.85E+03 -1.64E+03 -1.43E+03 -1.23E+03 -1.02E+03 -8.10E+02 -6.04E+02 -3.98E+02
0.801183 0.713815 0.631096 0.55268 0.478253 0.407534 0.340265 0.276213 0.215164 0.156924 0.101315
2.228175 2.041766 1.87967 1.737904 1.613254 1.503107 1.40532 1.318128 1.240065 1.169907 1.106625
0.690227 0.671244 0.652738 0.634757 0.617335 0.600496 0.584255 0.568617 0.553584 0.539151 0.525307
69.02275 67.12436 65.2738 63.47571 61.73354 60.04965 58.42549 56.86175 55.35844 53.91507 52.53071
165
2MH/nC7 Temperatu Temperature a re K eC 100 373 -1.92E+05 110 383 -1.92E+05 120 393 -1.92E+05 130 403 -1.92E+05 140 413 -1.92E+05 150 423 -1.92E+05 160 433 -1.92E+05 170 443 -1.92E+05 180 453 -1.92E+05 190 463 -1.92E+05 200 473 -1.92E+05
b
c
G nC7
a
b
c
G 2MH
∆G
ln K
K
X
X%
6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02
5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02
5.90E+04 6.59E+04 7.29E+04 7.98E+04 8.68E+04 9.37E+04 1.01E+05 1.08E+05 1.15E+05 1.22E+05 1.29E+05
-1.99E+05 -1.99E+05 -1.99E+05 -1.99E+05 -1.99E+05 -1.99E+05 -1.99E+05 -1.99E+05 -1.99E+05 -1.99E+05 -1.99E+05
6.58E+02 6.58E+02 6.58E+02 6.58E+02 6.58E+02 6.58E+02 6.58E+02 6.58E+02 6.58E+02 6.58E+02 6.58E+02
5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02
5.48E+04 6.18E+04 6.88E+04 7.59E+04 8.29E+04 9.00E+04 9.70E+04 1.04E+05 1.11E+05 1.18E+05 1.25E+05
-4.19E+03 -4.11E+03 -4.03E+03 -3.95E+03 -3.87E+03 -3.79E+03 -3.72E+03 -3.64E+03 -3.56E+03 -3.48E+03 -3.40E+03
1.350422 1.290441 1.233511 1.179405 1.127916 1.078861 1.032069 0.987389 0.944679 0.903813 0.864673
3.859053 3.634389 3.433263 3.252437 3.089213 2.941327 2.806869 2.684216 2.571988 2.469 2.37423
0.794199 0.784222 0.774433 0.764841 0.755454 0.746278 0.737317 0.728572 0.720044 0.711732 0.703636
79.41986 78.42218 77.44325 76.48407 75.54542 74.62783 73.73169 72.85719 72.00439 71.17325 70.36361
3MH/nC7 Temperatu Temperature a re K eC 100 373 -1.92E+05 110 383 -1.92E+05 120 393 -1.92E+05 130 403 -1.92E+05 140 413 -1.92E+05 150 423 -1.92E+05 160 433 -1.92E+05 170 443 -1.92E+05 180 453 -1.92E+05 190 463 -1.92E+05 200 473 -1.92E+05
b
c
G nC7
a
b
c
G 3MH
∆G
ln K
K
X
X%
6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02
5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02
5.90E+04 6.59E+04 7.29E+04 7.98E+04 8.68E+04 9.37E+04 1.01E+05 1.08E+05 1.15E+05 1.22E+05 1.29E+05
-1.96E+05 -1.96E+05 -1.96E+05 -1.96E+05 -1.96E+05 -1.96E+05 -1.96E+05 -1.96E+05 -1.96E+05 -1.96E+05 -1.96E+05
6.54E+02 6.54E+02 6.54E+02 6.54E+02 6.54E+02 6.54E+02 6.54E+02 6.54E+02 6.54E+02 6.54E+02 6.54E+02
5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02 5.65E-02
5.59E+04 6.29E+04 6.98E+04 7.68E+04 8.38E+04 9.09E+04 9.79E+04 1.05E+05 1.12E+05 1.19E+05 1.26E+05
-3.08E+03 -3.04E+03 -3.00E+03 -2.97E+03 -2.93E+03 -2.89E+03 -2.85E+03 -2.82E+03 -2.78E+03 -2.74E+03 -2.70E+03
0.993105 0.955376 0.919566 0.885533 0.853148 0.822293 0.792863 0.764761 0.737899 0.712197 0.687581
2.699603 2.599647 2.508202 2.424276 2.347023 2.275712 2.209713 2.14848 2.091536 2.038464 1.988899
0.729701 0.722195 0.714954 0.707967 0.701227 0.694723 0.688446 0.682386 0.676536 0.670886 0.665429
72.97007 72.2195 71.49537 70.79675 70.1227 69.47228 68.84457 68.23864 67.65362 67.08864 66.54286
166
22DMP/nC7 Temperatu Temperature a re K eC 100 373 -1.92E+05 110 383 -1.92E+05 120 393 -1.92E+05 130 403 -1.92E+05 140 413 -1.92E+05 150 423 -1.92E+05 160 433 -1.92E+05 170 443 -1.92E+05 180 453 -1.92E+05 190 463 -1.92E+05 200 473 -1.92E+05
b
c
G nC7
a
b
c
G 22DMP
∆G
ln K
K
X
X%
6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02
5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02
5.90E+04 6.59E+04 7.29E+04 7.98E+04 8.68E+04 9.37E+04 1.01E+05 1.08E+05 1.15E+05 1.22E+05 1.29E+05
-2.10E+05 -2.10E+05 -2.10E+05 -2.10E+05 -2.10E+05 -2.10E+05 -2.10E+05 -2.10E+05 -2.10E+05 -2.10E+05 -2.10E+05
6.86E+02 6.86E+02 6.86E+02 6.86E+02 6.86E+02 6.86E+02 6.86E+02 6.86E+02 6.86E+02 6.86E+02 6.86E+02
5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02
5.37E+04 6.10E+04 6.83E+04 7.56E+04 8.29E+04 9.02E+04 9.76E+04 1.05E+05 1.12E+05 1.20E+05 1.27E+05
-5.29E+03 -4.94E+03 -4.59E+03 -4.24E+03 -3.89E+03 -3.53E+03 -3.18E+03 -2.83E+03 -2.48E+03 -2.13E+03 -1.78E+03
1.704711 1.550164 1.403488 1.264096 1.13146 1.005101 0.884583 0.769511 0.659525 0.554294 0.453517
5.499794 4.712242 4.069368 3.539892 3.100181 2.732183 2.421975 2.158711 1.933873 1.740712 1.573838
0.846149 0.824937 0.802737 0.77973 0.756108 0.73206 0.707771 0.683415 0.659154 0.635131 0.611475
84.6149 82.49374 80.27368 77.97305 75.61083 73.20603 70.77711 68.34152 65.91536 63.51313 61.14752
23DMP/nC7 Temperatu Temperature a re K eC 100 373 -1.92E+05 110 383 -1.92E+05 120 393 -1.92E+05 130 403 -1.92E+05 140 413 -1.92E+05 150 423 -1.92E+05 160 433 -1.92E+05 170 443 -1.92E+05 180 453 -1.92E+05 190 463 -1.92E+05 200 473 -1.92E+05
b
c
G nC7
a
b
c
G 23DMP
∆G
ln K
K
X
X%
6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02
5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02
5.90E+04 6.59E+04 7.29E+04 7.98E+04 8.68E+04 9.37E+04 1.01E+05 1.08E+05 1.15E+05 1.22E+05 1.29E+05
-2.03E+05 -2.03E+05 -2.03E+05 -2.03E+05 -2.03E+05 -2.03E+05 -2.03E+05 -2.03E+05 -2.03E+05 -2.03E+05 -2.03E+05
6.65E+02 6.65E+02 6.65E+02 6.65E+02 6.65E+02 6.65E+02 6.65E+02 6.65E+02 6.65E+02 6.65E+02 6.65E+02
5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02
5.27E+04 5.98E+04 6.69E+04 7.39E+04 8.11E+04 8.82E+04 9.53E+04 1.02E+05 1.10E+05 1.17E+05 1.24E+05
-6.28E+03 -6.14E+03 -6.00E+03 -5.86E+03 -5.72E+03 -5.58E+03 -5.44E+03 -5.30E+03 -5.16E+03 -5.02E+03 -4.88E+03
2.023518 1.926974 1.835352 1.748287 1.665448 1.586534 1.511274 1.439421 1.370748 1.30505 1.242138
7.564889 6.868691 6.267342 5.744756 5.288042 4.886784 4.532504 4.218252 3.938296 3.687873 3.463009
0.883244 0.872914 0.862398 0.851737 0.840968 0.830128 0.81925 0.808365 0.797501 0.786684 0.775936
88.32443 87.29141 86.23981 85.17367 84.0968 83.0128 81.925 80.8365 79.7501 78.66837 77.59359
167
24DMP/nC7 Temperatu Temperature a re K eC 100 373 -1.92E+05 110 383 -1.92E+05 120 393 -1.92E+05 130 403 -1.92E+05 140 413 -1.92E+05 150 423 -1.92E+05 160 433 -1.92E+05 170 443 -1.92E+05 180 453 -1.92E+05 190 463 -1.92E+05 200 473 -1.92E+05
b
c
G nC7
a
b
c
G 24DMP
∆G
ln K
K
X
X%
6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02
5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02
5.90E+04 6.59E+04 7.29E+04 7.98E+04 8.68E+04 9.37E+04 1.01E+05 1.08E+05 1.15E+05 1.22E+05 1.29E+05
-2.06E+05 -2.06E+05 -2.06E+05 -2.06E+05 -2.06E+05 -2.06E+05 -2.06E+05 -2.06E+05 -2.06E+05 -2.06E+05 -2.06E+05
6.82E+02 6.82E+02 6.82E+02 6.82E+02 6.82E+02 6.82E+02 6.82E+02 6.82E+02 6.82E+02 6.82E+02 6.82E+02
5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02
5.64E+04 6.37E+04 7.09E+04 7.82E+04 8.55E+04 9.28E+04 1.00E+05 1.07E+05 1.15E+05 1.22E+05 1.29E+05
-2.54E+03 -2.23E+03 -1.92E+03 -1.61E+03 -1.29E+03 -9.81E+02 -6.68E+02 -3.55E+02 -4.24E+01 2.70E+02 5.83E+02
0.820507 0.700839 0.587269 0.479341 0.376646 0.278813 0.185506 0.096416 0.011267 -0.0702 -0.14821
2.271651 2.015443 1.799068 1.615009 1.457388 1.321561 1.203827 1.101218 1.01133 0.932208 0.862246
0.694344 0.668374 0.642738 0.617592 0.593064 0.569255 0.546244 0.524085 0.502817 0.482457 0.463014
69.43439 66.83738 64.27382 61.75922 59.30639 56.92553 54.62438 52.40855 50.28166 48.24574 46.3014
33DMP/nC7 Temperatu Temperature a re K eC 100 373 -1.92E+05 110 383 -1.92E+05 120 393 -1.92E+05 130 403 -1.92E+05 140 413 -1.92E+05 150 423 -1.92E+05 160 433 -1.92E+05 170 443 -1.92E+05 180 453 -1.92E+05 190 463 -1.92E+05 200 473 -1.92E+05
b
c
G nC7
a
b
c
G 33DMP
∆G
ln K
K
X
X%
6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02
5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02
5.90E+04 6.59E+04 7.29E+04 7.98E+04 8.68E+04 9.37E+04 1.01E+05 1.08E+05 1.15E+05 1.22E+05 1.29E+05
-2.05E+05 -2.05E+05 -2.05E+05 -2.05E+05 -2.05E+05 -2.05E+05 -2.05E+05 -2.05E+05 -2.05E+05 -2.05E+05 -2.05E+05
6.79E+02 6.79E+02 6.79E+02 6.79E+02 6.79E+02 6.79E+02 6.79E+02 6.79E+02 6.79E+02 6.79E+02 6.79E+02
5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02 5.63E-02
5.57E+04 6.29E+04 7.02E+04 7.74E+04 8.47E+04 9.19E+04 9.92E+04 1.06E+05 1.14E+05 1.21E+05 1.28E+05
-3.25E+03 -2.97E+03 -2.69E+03 -2.40E+03 -2.12E+03 -1.84E+03 -1.56E+03 -1.27E+03 -9.92E+02 -7.09E+02 -4.27E+02
1.048635 0.932509 0.8223 0.717567 0.617913 0.522978 0.432434 0.345984 0.263357 0.184305 0.108602
2.853753 2.540876 2.275728 2.049441 1.855053 1.687044 1.541003 1.413379 1.301291 1.202382 1.114718
0.740513 0.717584 0.694724 0.672071 0.649744 0.627844 0.606455 0.585643 0.565461 0.545946 0.527124
74.05127 71.7584 69.47243 67.20711 64.97438 62.78438 60.64546 58.56433 56.54612 54.59462 52.71238
168
2EP/nC7 Temperatu Temperature a re K eC 100 373 -1.92E+05 110 383 -1.92E+05 120 393 -1.92E+05 130 403 -1.92E+05 140 413 -1.92E+05 150 423 -1.92E+05 160 433 -1.92E+05 170 443 -1.92E+05 180 453 -1.92E+05 190 463 -1.92E+05 200 473 -1.92E+05
b
c
G nC7
a
b
c
G 2EP
∆G
ln K
K
X
X%
6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02 6.51E+02
5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02
5.90E+04 6.59E+04 7.29E+04 7.98E+04 8.68E+04 9.37E+04 1.01E+05 1.08E+05 1.15E+05 1.22E+05 1.29E+05
-1.93E+05 -1.93E+05 -1.93E+05 -1.93E+05 -1.93E+05 -1.93E+05 -1.93E+05 -1.93E+05 -1.93E+05 -1.93E+05 -1.93E+05
6.67E+02 6.67E+02 6.67E+02 6.67E+02 6.67E+02 6.67E+02 6.67E+02 6.67E+02 6.67E+02 6.67E+02 6.67E+02
5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02 5.64E-02
6.32E+04 7.03E+04 7.74E+04 8.45E+04 9.17E+04 9.88E+04 1.06E+05 1.13E+05 1.20E+05 1.27E+05 1.35E+05
4.25E+03 4.41E+03 4.58E+03 4.74E+03 4.90E+03 5.07E+03 5.23E+03 5.39E+03 5.56E+03 5.72E+03 5.88E+03
-1.37008 -1.38566 -1.40045 -1.41451 -1.42789 -1.44063 -1.45279 -1.46439 -1.47549 -1.4861 -1.49627
0.254086 0.250157 0.246485 0.243045 0.239815 0.236779 0.233918 0.231219 0.228667 0.226253 0.223964
0.202606 0.200101 0.197744 0.195524 0.193428 0.191448 0.189573 0.187796 0.18611 0.184507 0.182983
20.26065 20.01007 19.7744 19.55236 19.34282 19.14478 18.95733 18.77965 18.61101 18.45074 18.29825
169
Figure 3.1 C5 paraffin equilibrium plot
Equilibrium Curve
170
Iso-pentane equilibrium curve
2-2Dimethyl butane Equilibrium curve
171
APPENDIX D
Typical Baffles clearances and Tolerances
Shell Bundle Clearance
172
Tube side heat transfer Factor
173
Tube side friction factor 174
Shell side heat transfer factor, for segmental baffles 175
Shell side friction Factor, for segmental baffles 176
Temperature Correction factor: Two shell passes, four or multiple of four tube passes
Temperature Correction factor: One shell passes, two or even tube passes 177
Typical Overall Coefficients
178
Designing Algorithm for Heat Exchanger
179
Discharge Coefficient sieve plate
180
Pump selection guide
181
Pipe Friction verse Reynolds number and relative roughness
182
183
Compressor operating range
184
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