Power Plant Design Basis

KRISHAK BHARTI COOPERATIVE LIMITED REVAMP OF CAPTIVE POWER PLANT - HAZIRA (POWER PLANT DESIGN BASIS)

SECTION B-1.1

SECTION B – 1.1

POWER PLANT DESIGN BASIS

Page 1 of 16

SECTION B-1.1

KRISHAK BHARTI COOPERATIVE LIMITED REVAMP OF CAPTIVE POWER PLANT - HAZIRA (POWER PLANT DESIGN BASIS)

CONTENTS S. No.

DESCRIPTION

PAGE

1.

INTRODUCTION

3

2.

SITE CONDITION

3

3.

DESIGN DATA

4

4.

CAPTIVE POWER PLANT

4

5

DESIGN CONSIDERATIONS FOR CPP

10

SPECIAL DESIGN REQUIREMENTS FOR MAJOR 6

12 EQUIPMENTS

7.

REDUNDANCY PHILOSOPHY

15

8.

BUILDINGS / SHED

15

9.

ANNEXURE

15

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KRISHAK BHARTI COOPERATIVE LIMITED REVAMP OF CAPTIVE POWER PLANT - HAZIRA (POWER PLANT DESIGN BASIS)

1.

SECTION B-1.1

INTRODUCTION KRIBHCO is operating a mega Fertilizer Complex at Hazira, District Surat, in the State of Gujarat, India. The fertilizer complex comprises of two streams of Ammonia plants of 1520 MT/day capacity each and four Urea streams of 1310 MT/day each. The complex also comprises of related offsite facilities, Captive Power generation (CPP), Silos for storing urea, Railway siding etc. and is self sufficient in terms of power and other utilities. KRIBHCO has undertaken a major revamp project of Ammonia & Urea plants for capacity enhancement. The project is under implementation and has been scheduled to be completed by Dec. 2011. Present requirement of Power & HP steam by the fertilizer complex is 24MW and 260 MT/hr respectively. On completion of this revamp project, surplus HP steam will be generated in the Ammonia plants which will be exported to Urea plants. Under this scenario HP steam requirement from the SGPG plant shall reduce to 174 MT/hr from present level of 260 MT/hr. The power requirement of the complex however shall increase to 37 MW from present requirement of 24 MW. Thus the CPP (i.e. Steam and Power Generation plant), after revamp of fertilizer plant needs to produce 174 MT/hr HP steam and 37 MW power for in-house consumption. Beside this, the surplus power generated from CPP shall be exported to outside consumers through state / central grid.

2.

SITE CONDITION Metrological Data 1 2

3

4

5 6

1005 mbar (Average) 1014 mbar (Maximum)

Barometric pressure Design ambient conditions • Air temperature • Relative humidity • Wet Bulb temparature Ambient Condition • Maximum Ambient Air Temperature • Minimum Ambient Air Temperature • Maximum Ambient Relative humidity Rain fall • Average in a month • Heaviest in a day • Maximum in one hour Wind • Wind code • Base wind pressure: • Wind load Class of seismic area

35 Deg C 65% 32 Deg C 45 Deg C 4.0Deg C 87 % 325 mm 270 mm 100 mm IS-875-1964 150 KG/M2 Upto 30 M: 150 kg/m2 Zone-III according to BIS1893 (1975)

Site elevation:HIGHEST FLOOD level Road level DRAIN TOP LEVEL NGL in plant Area Finished floor level of building

: - 6.90 M above MSL : - 5.75 M above MSL : - 5.5 M above MSL : - 5.5- 5.75 M above MSL : - 6.00 M above MSL Page 3 of 16

KRISHAK BHARTI COOPERATIVE LIMITED REVAMP OF CAPTIVE POWER PLANT - HAZIRA (POWER PLANT DESIGN BASIS)

SECTION B-1.1

3.

DESIGN DATA

3.1

FUELS & FUEL SPECIFICATION Natural Gas at CPP battery Limit shall be available at 42.0 KG/Cm2g & at ambient temperature. Natural Gas specifications shall be as per Annexure – II.

3.2

POLLUTION CONTROL The stack pollutions level shall not exceed the following limits as a minimum requirement:S.N.

Parameter

Type of Fuel

Mg/NM3

1

Oxides of Nitrogen (NOX)

Gas Firing

100 ppm / 180 mg/m3

It shall be ensured to maintain the emission from CPP as per Norms/Guidelines of Central Pollution Control Board / Gujarat State Pollution Control Board. 3.3

NOISE LEVEL The noise level shall not exceed than 85 dBa at a distance of 1 meter from source of individual Equipment. The noise in CPP and adjacent area shall be restricted within limit specified by statutory standard for Pollution control.

4.

CAPTIVE POWER PLANT (CPP) The Captive Power Plant (CPP) of KRIBHCO Fertilizer complex is intended to meet the revised internal steam and power requirement. CPP is to be designed to export 72 ± 2 MW power and 190 TPH of peak HP steam from CPP block. Part of the total exported power shall be used in the fertilizer complex and rest of the surplus power shall be sold to grid.

4.1

BRIEF PLANT DESCRIPTION Existing configuration of CPP: Existing steam and power requirement of fertilizer complex is 260 TPH and 24 MW which used to be met through gas fired utility boilers and STGs. Existing Captive Powe Plant (CPP) consists of three high pressure boilers, two extraction cum condensing type Steam Turbine Generator sets, two deaerators, four boiler feed water pumps, two HP heaters, two make-up tanks and make-up pumps as specified below. Existing facilities which are in common shall be utilized to the maximum extent i.e. deaerator, boiler feed water pumps, two make-up tanks and make-up pumps etc shall be utilized for the new GTG-HRSGs. After installing the new equipment in the CPP, existing boilers and STGs will not be required for operation for normal operation, however for upset conditions or under shutdown of new GTG- HRSG existing boilers and STGs will be put in operation to meet the demand. The Existing CPP consists of the following major equipment. 1. Utility Boilers:I.

Numbers :- 3

II.

Capacity :- 275 TPH each Page 4 of 16

KRISHAK BHARTI COOPERATIVE LIMITED REVAMP OF CAPTIVE POWER PLANT - HAZIRA (POWER PLANT DESIGN BASIS)

III.

SH outlet pressure:- 105 kg/cm2g

IV.

SH outlet temperature:- 510 deg C

V.

Fuel:- Dual Fuel (Natural Gas & NGL/Naphtha)

SECTION B-1.1

2. Steam Turbine Generator:I.

Numbers :- 2

II.

Capacity: 15 MW each

III.

Type :- Double Extraction cum condensing

IV.

Inlet Steam parameter :- HP steam 101 kg/cm2 abs & 505 deg C

V.

MP controlled extraction: 14 ± 1 kg/cm2 abs

VI.

LP uncontrolled extraction:- 2.7 kg/cm2 abs

VII.

Speed :- 7500 rpm

3. Deaerator:I.

Numbers:- 2

II.

Type:- Spray cum tray

III.

Water output :- 315 TPH

IV.

Maximum working/ design pressure:- 1.725 /2.03 kg/cm2 abs

V.

Maximum working / design temperature:- 115 /155 deg C

VI.

Oxygen in outlet water ml/L:- 0.0005 ml/l

4. Boiler Feed pumps:I.

Numbers:- 4

II.

Capacity:- 315 TPH

III.

Discharge pressure/shut off head: 137.6 / 178 kg/cm2 g.

IV.

Type :- Two motor driven and two steam turbine driven

5. Make-up water tank: i.

No. of Tank- 2 Nos.

ii.

Design pressure : 100 mmwc

iii.

Design code: API Spec 12 D

iv.

Design Temp: 100 Deg C

v.

Duty- Tones : 140

vi.

Plate material: BS 4360-43A

6. Make-up water pump: I.

No. of pump: Three (03)

II.

Type: 6”/6” D.ME.K MEDIVANE (YP 18.2K)

III.

Discharge quantity: 285.4 TPH

IV.

Delivery head: 6.77 kg/cm2g

V.

Shut of Head: 9.0 kg/cm2g Page 5 of 16

KRISHAK BHARTI COOPERATIVE LIMITED REVAMP OF CAPTIVE POWER PLANT - HAZIRA (POWER PLANT DESIGN BASIS)

SECTION B-1.1

Proposed Configuration for Captive Power Plant: Normal steam and power requirement after revamp of fertilizer plant will be 37 MW and 174 TPH. Configuration of the CPP shall consist of either one or two similar gas turbine generator(s) (GTG) and supplementary fired Heat recovery Steam Generator (HRSG) downstream of each GTG. The capacity details of the additional equipment shall be as per Cl. No. 4.2 bellow. Existing Deaerator, make-up water pump and BFPs (Boiler feed water pumps) will be utilized to feed the BFW (boiler feed water) to the new HRSG(s). 4.2

BRIEF SCOPE OF WORK AND DESCRIPTION 1.

Gas Turbine Generator (GTG) Type Quantity Capacity (Min)

Industrial Heavy Duty Type 1 No. or 2 Nos. of similar type and model. 1 x (72 ± 2) MW or 2 x (36 ± 1) MW The use of Vapour absorption type chiller* is also acceptable in case single GTG is offered by the Bidder. However power augment limit from chiller is upto 72 MW export power only. If required provision of DM Water /Steam injection limited to the extent for meeting only NOx emission should be provided. However GTG capacity (72 ± 2 MW) shall be considered without any DM water/ steam injection. (*Use of evaporative cooler for power augmentation is not acceptable. Standard specification for vapour absorption refrigeration package is attached as annexure - VII) Medium for NOx control - DM-WATER/ STEAM (if required) Guarantee fuel - Natural Gas (as per Annexure - II). Design Ambient Temperature - 35 deg C Design RH - 65 % Barometric pressure - 1005 mbar 2.

-

Heat Recovery Steam Generators (HRSGs) Quantity Type Steam Parameters. Capacity (Min.)/HRSG Fuel: Design Code

- 1 No. or 2 nos. of similar type and model (Associated with GTG) - Horizontal, Natural circulation with supplementary firing - HP (to suit the parameter at tap-off point) - 190* / 2 x 95* TPH Steam Generation (with supplementary firing) (bidder to confirm) - Natural Gas. PLC based BMS shall be provided. - Indian Boiler Regulation (IBR) latest Edition.

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KRISHAK BHARTI COOPERATIVE LIMITED REVAMP OF CAPTIVE POWER PLANT - HAZIRA (POWER PLANT DESIGN BASIS)

3.

SECTION B-1.1

(*HRSG capacity is to be selected so that net export of 190 TPH HP steam from CPP after meeting internal steam consumption i.e. gas heating, chiiler etc. is ensured.) Turn down of HRSG - : ≤ 30% of MCR (@ Rated steam pressure & temperature) GAS CONDITIONING SKID:Gas conditioning skid shall be suitable for CPP requirement. Gas conditioning skid shall consists of 1x100% Knock out drum (gas Scrubber) for GTG/HRSG stream. Pressure reduction valves, filter etc. shall be 2x100% for each services i.e. GTGs & HRSGs. If gas heating is required, 2x100% steam gas heater and 1x100% electric gas heater shall be provided. Gas line from gas condition skid to Gas turbine inlet shall be properly insulated. Suitable steam/Electric tracing system shall be provided if required.

4.

COOLING TOWER ( for BLACK START & NORMAL OPERAION):Cooling water requirement for the new GTG and HRSG shall be met through separate Cooling Tower and the same shall be in bidder’s scope. Cooling tower capacity shall be of based on cooling water required for GTGs and HRSGs. Bidder shall also provide 2 x 100% cooling water pumps. Each pump shall be suitable for meeting the Cooling water requirement of all GTGs and HRSGs along with other equipment in their scope. All pumps shall discharge cooling water to a common discharge header and all the cooling water shall be fed through this header. A tapping form discharge header is to be provided for future similar unit. All pumps shall be motor driven. (One of these cooling water pumps shall be sourced from both normal as well as emergency power) Cooling water system shall have also provision of hooking up at Battery limit with the existing cooling water system with isolation valves.

5.

Either GTG shall be provided with diesel engine for cranking of GTG during starting up or GTG shall consist of a static frequency converter (SFC) so as gas turbine generator shall act as starting motor for cranking during start-up through grid. Emergency power for black start shall be made available at battery limit. Bidder to submit requirement of emergency power along with bid and make provision for supply of emergency power in their MCC. The Ratings / Capacities of the HRSGs, given above are only minimum. Net export of 190 TPH of HP steam from CPP shall be ensured. Tentative layout is attached as Annexure – III.

4.3

Integration of Additional Power Equipments with existing set-up: All existing system shall be used to the maximum extent possible. Some major present facilities as follows are to be utilized. • Existing HP steam export header to fertiliser complex. The proposed new HRSGs steam shall be connected to this header. Page 7 of 16

KRISHAK BHARTI COOPERATIVE LIMITED REVAMP OF CAPTIVE POWER PLANT - HAZIRA (POWER PLANT DESIGN BASIS)

4.3.1

SECTION B-1.1

•

LP steam generated shall be exported to existing CPP for use in Deaerator. LP steam header shall be connected to existing LP steam header of existing CPP.

•

Existing Feed water system- Feed water required for new HRSG shall be sourced from this header.

•

Existing Condensate system: - Condensate as required for Make-up heater (MUH) of new HRSG shall be provided from existing header. Existing make up pump (refer cl. 4.1 sl. No.5 of this document) shall be used to source the condensate to MUH. Bidder to confirm the parameter at the tap off point. Bidder to provide isolation valves at inlet and outlet header along with control valve to each MUH.

•

Condensate after heating in HRSG shall be sent to existing Deaerator.

•

Existing Dearator- The existing Deaerators shall be used to feed BFW to HRSG.

•

Make-up for cooling water system: - Separate cooling system to be provided for meeting the GTG-HRSG cooling water requirement for normal as well as black start. Make-up for cooling tower shall be provided at battery limit. However provision for hook up with existing cooling circuit at Battery limit is also to be provided.

•

Existing Instrument air system- Instrument air required for CPP shall be sourced from existing IA system.

•

Plant air system: - To be Sourced from existing system.

•

Service water system: - To be sourced from existing system.

•

Drinking water system: - To be sourced from existing system.

•

Fuel system- Fuel gas for gas conditioning skid (new GTGs & HRSGs) shall be supplied at CPP battery limit.

•

Electrical system- Refer electrical specification.

•

Control system - Refer Instrument specification.

STEAM The steam generated from new Heat Recovery Steam Generator (HRSG) is to be hooked up to existing HP header located in existing CPP. All existing utility boilers are connected to this header and HP steam demand of the fertilizer plant will be met through this header from CPP. Header from HRSGs shall be designed to export of 300 TPH of BFW and HP steam to existing HP header. (Bidder to note that with future HRSG max HP export to the fertilizer complex shall be 300 TPH). Bidder to note that CBD vent is also to be connected with existing LP header to optimise water and fuel consumption.

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SECTION B-1.1

KRISHAK BHARTI COOPERATIVE LIMITED REVAMP OF CAPTIVE POWER PLANT - HAZIRA (POWER PLANT DESIGN BASIS)

4.3.2

STEAM PARAMETERS AT HOOK-UP POINT (at Existing Power plant header) SERVICE

HP steam CPP LP steam 4.3.3

Norm al 103 510 0.8 std

PRESSURE, kg/cm²g TEMPERATURE, °C PRESSURE, kg/cm²g TEMPERATURE, °C

Max

Min

Design

107 520 2.0 190

102 500 0.5 std

123.4 535 3.5 205

BFW PARAMETERS AT HOOK- UP POINT (at Existing Power plant header) SERVICE

CPP 4.3.4

PRESSURE, kg/cm²g TEMPERATURE, °C

Normal

Max

Min

135 115

150 115

120 115

Desig n 180 130

CONDENSATE PARAMETERS AT HOOK-UP POINT FOR MAKE-UP WATER HEATER OF HRSG (at Existing Power plant header) SERVICE INLET OUTLET

4.3.5

PRESSURE, kg/cm²g TEMPERATURE, °C PRESSURE, kg/cm²g TEMPERATURE, °C

Normal 6.77 45 85

Max 9.0 70 90

Min 40 -

Design 10.0 100 100

STEAM AND POWER DEMAND FOR FERTILIZER COMPLEX Refer Annexure -V for Fertiliser complex normal and offset scenario.

4.3.6

STEAM QUALITY PH Total Fe Copper Silica as SiO2 Cation Conductivity @ 25 deg C

4.3.7

>8.3 0.02 mg/l ( Max) < 0.003 mg/l 0.02 mg/l ( Max) 0.2 micro-mho/cm ( max)

BFW QUALITY PH Silica as SiO2 Cation Conductivity @ 25 deg C or ambient Dissolved oxygen Total iron Copper Hardness

8.0 TO 9.0