FRI VOLUME 5: FRACTIONATION DESIGN HANDBOOK
INTRODUCTION
Issued: Rev i s ed :
11/10/08
0.01
10/30/13
INTRODUCTION
INTRODUCTION ...................................................................................................................................... 1
Introduction ..................................................... ............................................................................................................. ............................................................................................ .................................... 2 Design Practices Committee ............................................................................................ ........................... 3 .............................................................................................................. ............................................................................................ .................................... 4 Consultants ......................................................
Past Members .................................................. ........................................................ ............................................................................................ .................................... 4 Past Consultants ...................................................................................................... .................................... 5
Page 1 of 5
Issued: 11/10/08 Revised: 10/30/13
1
INTRODUCTION
0.01
Introduction
This document was prepared by the Design Practices Committee of FRI at the request and direction of the Technical Committee and the Technical Advisory Committee. It is based primarily on standards and practices received from member companies willing to volunteer such material. The idea of a Design Practices Committee was approved at the December 1974 meeting of the TAC. The committee was organized in 1975 and met for the first time in April 1976. There were three other meetings in 1976. In 1977 and succeeding years, the committee has met and will meet immediately prior to and/or immediately following the semi-annual meetings of the TAC. When the TAC meets outside the US the DPC generally meets in Houston a couple of weeks prior to the TAC meeting. Past and present members are listed later later in this Introduction. Little in this volume is entirely new. Almost everything is based on information which was first received from one or more member companies and then compiled and edited by the committee. The information in this document was issued piecemeal as it was produced in order to make it available to the FRI membership as soon as possible. Some portions are incomplete and must be used with that understanding. The ideas contained herein should be applied to various situations with the same forethought and attention to detail that should characterize any good engineering design. The continuation, expansion and quality of this manual requires feedback from the FRI membership on the designs so far presented and additional information in areas which have not so far been covered by contributions. All designs in the book will benefit from comments, criticisms, and additional contributions. In areas where the information available is inadequate, partially completed, completed, or even totally missing, sheets are included to highlight the need for additional information. The addresses, telephone numbers, and E-mail addresses of all current committee members are listed below. Contributions can be made orally or in writing to any current member or, by prior appointment, to the entire committee at one of its scheduled sessions. The information provided in this volume of Design Practices has been collected by the Design Practices Committee (DPC) of the Technical Advisory Committee (TAC) of Fractionation Research, Inc. (FRI) from information supplied by FRI member companies. This information does not result from research performed by FRI and has not been evaluated by the FRI staff, the FRI Technical Committee or the TAC. The use of any information in this manual must be totally at the risk of the user. Current and past DPC members, FRI member companies, and FRI hereby disclaim responsibility for any damages incurred directly or indirectly by the use of information in this manual. Fractionation Research Inc. and its Design Practices Committee do not represent, warrant, or otherwise guarantee, expressly or implicitly, that following the procedures and recommendations outlined in this document will satisfy any specific need any user of this manual has or the suitability, accuracy, reliability, or completeness of the information or procedures contained herein. The users of these procedures and recommendations apply them at their own election and at their own risk. FRI, the DPC, and the contributors to this document each expressly disclaims liability for any loss, damage or injury suffered or incurred as a result of or related to anyone using or relying on any of the procedures and recommendations in this document. The information and recommended practices included in this document are not intended to replace individual company standards or sound judgment in any circumstances. circumstances. The information information and recommendations in this document are offered as guidelines only for the development of individual company standards and procedures.
Page 2 of 5
Issued: 11/10/08 Revised: 10/30/13
1
INTRODUCTION
0.01
Introduction
This document was prepared by the Design Practices Committee of FRI at the request and direction of the Technical Committee and the Technical Advisory Committee. It is based primarily on standards and practices received from member companies willing to volunteer such material. The idea of a Design Practices Committee was approved at the December 1974 meeting of the TAC. The committee was organized in 1975 and met for the first time in April 1976. There were three other meetings in 1976. In 1977 and succeeding years, the committee has met and will meet immediately prior to and/or immediately following the semi-annual meetings of the TAC. When the TAC meets outside the US the DPC generally meets in Houston a couple of weeks prior to the TAC meeting. Past and present members are listed later later in this Introduction. Little in this volume is entirely new. Almost everything is based on information which was first received from one or more member companies and then compiled and edited by the committee. The information in this document was issued piecemeal as it was produced in order to make it available to the FRI membership as soon as possible. Some portions are incomplete and must be used with that understanding. The ideas contained herein should be applied to various situations with the same forethought and attention to detail that should characterize any good engineering design. The continuation, expansion and quality of this manual requires feedback from the FRI membership on the designs so far presented and additional information in areas which have not so far been covered by contributions. All designs in the book will benefit from comments, criticisms, and additional contributions. In areas where the information available is inadequate, partially completed, completed, or even totally missing, sheets are included to highlight the need for additional information. The addresses, telephone numbers, and E-mail addresses of all current committee members are listed below. Contributions can be made orally or in writing to any current member or, by prior appointment, to the entire committee at one of its scheduled sessions. The information provided in this volume of Design Practices has been collected by the Design Practices Committee (DPC) of the Technical Advisory Committee (TAC) of Fractionation Research, Inc. (FRI) from information supplied by FRI member companies. This information does not result from research performed by FRI and has not been evaluated by the FRI staff, the FRI Technical Committee or the TAC. The use of any information in this manual must be totally at the risk of the user. Current and past DPC members, FRI member companies, and FRI hereby disclaim responsibility for any damages incurred directly or indirectly by the use of information in this manual. Fractionation Research Inc. and its Design Practices Committee do not represent, warrant, or otherwise guarantee, expressly or implicitly, that following the procedures and recommendations outlined in this document will satisfy any specific need any user of this manual has or the suitability, accuracy, reliability, or completeness of the information or procedures contained herein. The users of these procedures and recommendations apply them at their own election and at their own risk. FRI, the DPC, and the contributors to this document each expressly disclaims liability for any loss, damage or injury suffered or incurred as a result of or related to anyone using or relying on any of the procedures and recommendations in this document. The information and recommended practices included in this document are not intended to replace individual company standards or sound judgment in any circumstances. circumstances. The information information and recommendations in this document are offered as guidelines only for the development of individual company standards and procedures.
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Issued: 11/10/08 Revised: 10/30/13
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INTRODUCTION
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Design Practices Committee Anthony Avilla (2012- ) Dow 2301 Brazosport Blvd, APB Building Freeport, TX 77541-3257 Tel: 979-238-9152; Fax: 979-238-0788 E-Mail:
[email protected]
Joseph Parker, P.E. (1991- ) [Vice Chair] Eastman Chemical Company P.O. Box 511, Kingsport, TN 37662-5054 Tel: 423-229-3850; Fax: 423-224-0453 E-Mail:
[email protected] E-Mail:
[email protected] Attilio Praderio (2010-) ConocoPhillips LNG Product Development Center, Room 14E566, 3000 Post Oak Blvd., Room 14E566 Houston, TX 77356 Tel: 713-235-3973; 713-822-3818 E-Mail:
[email protected]
Jeffery A. Bell, P.E. (2007- ) UOP LLC A Honeywell Company 25 East Algonquin Road Des Plains, IL 60017-5017 Tel: 847-391-2237; Fax: 847-391-2758 E-Mail:
[email protected] E-Mail:
[email protected]
Dan Summers, P.E., F.AIChE (2002- ) [Chair] Sulzer Chemtech USA, Inc. 1 Sulzer Way, Tulsa, OK 74131 Tel: 918-447-7654; Fax: 918-446-5321 E-Mail:
[email protected]
Jeremy Brauer (2012 - ) UOP LLC 175 East Park Drive P.O. Box 986 Tonawanda, NY 14151-0986 Tel: 716-879-7416; Fax: 716-879-7215 E-Mail:
[email protected] E-Mail:
[email protected]
Zhongcheng Wang, Ph.D. (2012- ) ExxonMobil Research and Engineering Co. 3225 Gallows Road Fairfax, VA 22037 Tel: 703-846-4704; Fax: 703-846-2567 E-Mail:
[email protected]
Wm Randall Hollowell (2011 - ) CITGO Petroleum Corporation PO Box 1562 Lake Charles, LA 70602 Tel: 337-708-8219; 337-912-7478 E-Mail:
[email protected] Henry Kister, F.AIChE, F.IChemE, NAE (1985- ) Fluor 3 Polaris Way, Aliso Viejo, CA 92698 Tel: 949-349-4679; Fax: 949-349-2898 E-Mail:
[email protected] Paul Morehead, P.E. (1996- ) Koch-Glitsch, L.P. 4900 Singleton Boulevard, Dallas, TX 75212 Tel: 214-583-3358; Fax: 214-583-3344 E-Mail: paul.morehead@kochgli E-Mail:
[email protected] tsch.com F. Ronald (Ron) Olsson, P.E., F.AIChE (1998- ) Celanese Ltd P.O. Box 428 Highway 77 South, Bishop, TX 78343 Tel: 361-584-6455; Fax: 972-332-9109 E-Mail:
[email protected]
Keith Whitt (2010- ) Shell Projects and Technology (US) Westhollow Technology Center 3333 Hwy 6 South Houston, TX 77082-3101 Tel: 281-544-8299; 282-797-0368 E-Mail:
[email protected] Simon Xu, Ph.D. (2013- ) Technip 1430 Enclave Parkway Houston, TX 77077 Tel: 281-848-5000; 713-570-0611 E-mail:
[email protected] Norman Yeh, Ph.D. (2013- ) ExxonMobil PO Box 2189 Houston, TX 77252-2189 Tel: 713-431-6483; Fax: 713-431-6387 E-Mail:
[email protected]
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Issued: 11/10/08 Revised: 10/30/13
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INTRODUCTION
Consultants
Douglas Bouck (2000- ) Separation Solutions, Ltd. 503-20 Concord Downs Ln, Aurora, OH 44202 Tel: 440-248-4766 E-Mail:
[email protected] John P. Farone (2006- ) 511 Fern Court, Cedar Park, TX 78613 Tel: 979-292-4792 E-Mail:
[email protected] E-Mail:
[email protected] Neil Yeoman, P.E., F.AIChE (2002- ) [Secretary] LNCK Associates 1723 Alexis Road, Merrick, NY 11566-4822 Tel: 516-946-9530 E-Mail:
[email protected]
4
Past Members
Larry Angermeier (Union Carbide), 1976-84; Vice Chairman, 1982-84 John Aycock (Tennessee Eastman), 1982-90; Chairman, 1989-90 Dave Bachman (ARCO Products), 1989-1997 Dan Bensing (Tennessee Eastman), 1979-81 Mike Binkley (Glitsch), 1979-1995 Barry Boothroyd (ICI), 1976-81; Vice Chairman, 1976-78, Chairman, 1978-81 Doug Bouck (BP), 1998-1999 Jose Bravo (Shell), 1992-2004, Chairman, 1998-2004 John Brierley (ICI), 1981-92 Gregory Cantley (Marathon Petroleum Company LLC), 2009 Hugo DeAngelis (Marathon), 2005-2008 Waldo de Villiers (Shell Global Solutions (U.S.), Inc.), 2004-10 Brad Fleming (Raschig-Jaeger), 2011-2013 Joe Flowers (E.I. Dupont de Nemours & Company), 2002-10 Gerald Geyer (Dow Chemical), 1989-1993 Ed Grave (ExxonMobil), 1993-2013 Ron Harrison (Nutter Engineering), 1978-87 Bud Jamison (Nutter Engineering), 1976-78 Layton Kitterman (Glitsch), 1976-79; Secretary, 1976-79 James Lucas (Tennessee Eastman), 1976-78; Chairman 1976-78 Bob Markeloff (Shell), 1993-94 Todd Marutt (ExxonMobil), 2000-2012 Mark Mastroianni (Tennessee Eastman), 1981-82 Donald Meyer (C.W. Nofsinger), 1989-91
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0.01
Issued: 11/10/08 Revised: 10/30/13
INTRODUCTION
Dave Perry (Nutter Engineering), 1987-1997 Angel Peruyero (Exxon), 1997-2000 Mark Pilling (Sulzer), 1997-2002 Derek Reay (BP), 1982-1998, Chairman 1990-1998 Frank Rukovena (Norton), 1992-1996 Ron Smith (Tennessee Eastman), 1978-79 Ray Sowiak (Mobil, Sunoco, AMACS), 1996-2000, 2004-08, 2013 Berne Stober (Mobil), 1990-94 Larry Wilder (Union Carbide/Dow), 1989-2012 Simon Xu (Stone & Webster/Shaw), 2008-2012 Neil Yeoman (Scientific Design, Koch-Glitsch), 1976-2001, Chairman 1981-1989 Simon Yeung (Mobil), 1985-88
5
Past Consultants Frank Rukovena (2004-2006) Ray Sowiak (2002-2004)
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0.01
FRI VOLUME 5: FRACTIONATION DESIGN HANDBOOK
CONTENTS
Issued: Revised:
11/10/2008
0.02
10/10/2011
FRI DESIGN PRACTICES HANDBOOK – VOLUME 5
(Entries in Italics are Being Further Developed)
FRI DESIGN PRACTICES HANDBOOK – VOLUME 5 ....................................... ................................. 1 1.
Contents .................................................. ............................................................................................. 2 1.1
General ............................................... ............................................................................................ 2
1.2
Trayed Towers ................................................ ............................................................................... 2
1.3
Packed Towers ............................................... ................................................................................ 2
1.4
All Towers...................................................................................................................................... 3
Page 1 of 4
Issued: 10/13/2008
CONTENTS
Revised: 03/24/2011
1
0.02
Contents 1.1
General
0.01 0.02 0.03 0.04 0.05 0.06
1.2
10/15/07 2/10/08 1/15/95 1/15/98 1/15/92 11/1/88
Trayed Towers
1.00 1.01 1.02 1.03 1.04 1.05 1.05.1 1.05.2 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14.1 1.14.2 1.15 1.16 1.17 1.18 1.19 1.20 1.21
1.3
Introduction Contents Definitions References Reading List Index
General Notes Inlets - Top - Intermediate - Bottom Outlets - Top - Intermediate - Intermediate Liquid Drawoff - Intermediate Vapor Drawoff Reboiler Circuits For Trayed Columns Tray Transitions Weir Types
3/1/78 3/1/78 3/1/78 3/1/78 3/1/78 3/1/78 10/1/06
Tray Blank ing Tray Levelness Tray Gasketing Tray Design, Construction and Assembly Tray Mechanical Strength Perforated Pipe Distributors Low Liquid Rate Designs Tray Data Sheet Leak Tightness Cartridge Trays De-Rating Factors – Trayed Columns Tray Damage Caused by Harmonic Vibrations
9/1/81 11/1/01 4/15/85 1/15/97 1/15/97 7/15/83 10/30/85 12/15/90 5/1/89 7/25/08 1/15/94 2/1/06
10/1/06 3/1/78
Packed Towers
2.01.1 2.01.2 2.01.3 2.02.1 2.02.2 2.02.3 2.02.4
Ordering and Supply of Packing Installation of Packing Discharging of Packing Liquid Distribution for Packing Internal Pipework to Packed Tower Distributors Redistribution in Packed Columns Liquid Flow Through Gravity Distributor Orifices
Page 2 of 4
10/30/85 4/15/85 1/30/86 11/11/13 1/15/92 1/15/95 1/31/98
Issued:04/06/2010
CONTENTS
Revised: 10/10/2011
1
0.02
Contents (cont’d) 1.3
Packed Towers (cont’d)
2.03 2.04 2.05.1 2.05.2 2.05.3 2.05.4 2.05.5 2.05.6 2.05.7 2.06 2.07 2.08 2.09 2.10 2.11 1.4
Bed Limiters and Hold Down Plates Support Plates Inlets - Top - Intermediate - Bottom Outlets - Top - Intermediate Liquid Drawoff - Intermediate Vapor Drawoff - Bottom Transitions Packing Data Sheet Sampling in Packed Columns
11/1/99 11/1/88
De-Rating Factors - Packed Columns Packing Fires
1/15/94 6/15/03
10/1/06
12/15/90 12/15/98
All Towers
3.01.1 Troubleshooting Techniques 3.01.2 Designing Fractionation Systems to Aid Troubleshooting 3.01.3 Diagnostics Using Radioactive Isotopes 3.01.4 Other Diagnostic Techniques 3.01.5 Problems and Solutions 3.02 Designing Fractionation Systems to Aid Maintenance 3.03 Designing for Fouling Services 3.04 Designing for Ease of Installation 3.05 Location of Instruments 3.07 Design of Small Scale Columns 3.08 Dimensional Tolerances 3.15 Distillation Tower Startup and Shutdown 3.20 Performance Testing 3.50 Process Simulations 3.61 Middle Boilers 4.01 Surge 4.02 R emoval of Entrained Liquids 4.02.01 - Wire Mesh Type Mist Eliminators 4.02.02 - Trays and Packing as Mist Eliminators 4.03 Exchangers in Fractionation Service 4.03.1 - Reboilers 4.03.2 - Condensers 4.03.3 - Other Tower Heat Exchangers 4.03.4 - Miscellaneous 4.04 Vortex Breakers 4.50.01 Case Study #1 – Packed Column Trouble Shooting 4.50.02 Case Study #2 – An Intermediate Liquid Drawoff Problem 4.50.03 Case Study #3 – How to Design an FRI Small Scale Column
Page 3 of 4
1/15/98 1/15/98 12/16/09
11/1/88 12/15/90 1/15/96 1/15/95 10/10/08 6/15/03 8/31/04 5/24/06 8/15/03 10/6/11 3/23/11 12/15/90 1/15/92 12/15/90 1/15/95 1/15/95 1/15/97
2/15/93 10/1/06 10/1/06 10/1/06
Issued: 10/13/2008 Revised: 10/10/2011
1
CONTENTS
0.02
Contents (cont’d) 1.4
All Towers (cont’d)
5.01 Inspection of Pressure Vessels 5.01.01 - General Inspection Guide for Pressure Vessels 5.01.02 - Supplemental Inspection Guide for Pressure Vessels (Special Conditions) 5.01.03 - Supplemental Inspection Guide for Pressure Vessels (Critical Inspection Regions for Existing Vessels) 5.01.04 - Supplemental Inspection Guide for Pressure Vessels (Non-Destructive Testing) 5.01.05 Definition of Common Terms 5.02 Routine Inspection of Column Internals 5.02.01 Supplemental Guide to Visual Examination of Distillation Tower Internals 5.02.02 - Checklist for Visual Examination of Tray Installation (Vessel Shop or Field) 5.02.03 - Checklist for Visual Examination of Packed Tower Internals Installation (Field) 5.02.04 - Checklist for Visual Examination of Trays (Tray Vendor Shop) 5.02.05 - Checklist for Visual Examination of Packed Tower Internals (Vendor Shop) 5.05 Leveling Trays and Distributors
Page 4 of 4
2/15/93 2/15/93 2/15/93 2/15/93 2/15/93
6/15/03 6/15/03 6/15/03 6/15/03 6/15/03 1/15/96
FRI VOLUME 5: FRACTIONATION DESIGN HANDBOOK
DEFINITIONS
Issued: Revised:
09/01/1981
0.03
01/15/1995
DEFINITIONS
DEFINITIONS ............................................... ................................................... .......................................... 1 1.
Definitions ................................................ ............................................................................................ 2
Issued: 09/01/81 Revised: 01/15/1995
1
DEFINITIONS
0.03
Definitions TOWER (OR COLUMN) ATTACHMENTS - Tower attachments are permanent items of tower hardware welded to the vessel, generally by the vessel fabricator. Because of the method of attachment, they are occasionally also called "weld-ins" or "weld-ons". There are internal and external attachments. This manual refers to, and is concerned with, selected internal attachments including support rings, bolting and clamping bars, beam seats (also called beam foot rests), clips and brackets. These are provided to support and/or secure various tower (or column) internals provided by the vessel fabricator or by others. (See "tower internals".) TOWER (OR COLUMN) INTERNALS - Tower internals are generally (but not always) removable items of tower hardware provided to achieve a process effect. These include trays, packings, distributors and redistributors, de-entrainment devices, packing support plates, packing hold-down plates, bed limiters, impingement plates, baffles, pipes, ducts, channels, internal sumps, etc. They may be provided by the vessel supplier or by others.
Common terminology can cause some confusion. Internal attachments are used to support and secure, but there are internals whose names suggest that kind of function. Packing support plates, hold-down plates and bed limiters are internals. There are manufacturer's brochures that are labeled "packing and Packed Tower Internals" which should more correctly be labeled "Packing and Other Packed Tower Internals" because packing is an internal. Another bit of confusion occurs because some internal attachments are designed by the supplier of the internals those attachments must support and/or secure. The tray supplier designs the attachments that hold the trays he will supply. He designs the tray support rings, the downcomer clamping (or bolting) bars, beam seats and beam clips. The supplier of packed tower internals designs the rings and clips to support and/or secure the equipment he provides. TOP INSTALLABLE (REMOVABLE) - Trays are top installable, or top removable, if they are designed to be installed from the bottom up and removed from the top down, and the people doing most (but not necessarily all) of the installation or removal work are located above the tray being installed or removed. Specification that a tray be "top installable" does not necessarily assure that a tray, or any of its components, can be installed by people located exclusively above the tray, that is, with no assistance from below the tray. If this is required, it must be clearly stated in the language of a relative layman. (See Section 1.14.)
If it is desired that trays be installable from above with no assistance from below, the tray supplier must permanently and properly fasten (generally by welding) to appropriate other tray components many of the nuts (and/or bolts) to be used to fasten the tray components together. This is costly, being typically above five percent of the total purchased cost of the uninstalled trays. However, such trays are easier and cheaper to install because of reduced requirements, and may be the economically preferred alternate even for initial installation. DE-RATING - De-rating is an adjustment, generally by the appropriate application of (de-rating) factors less than unit, to the design or rating of a fractionation tower to take into account that for some services and/or in some situations towers provide less capacity than the (unmodified) correlation being used would otherwise predict. Three reasons for de-rating are generally recognized, each with a different name for the de-rating factor: • •
foaming (foaming factor), physical properties (system factor), and, Page 2 of 12
Issued: 09/01/81
DEFINITIONS
Revised: 01/15/1995
•
0.03
uncertainty (safety factor).
The de-rating may be based on one or more of these considerations. De-rating may be applicable to all performance and design variables under consideration, but is most commonly applied to capacity. De-rating may be based on the experience and subjective judgement of the designer or some more formalized procedure. Some design and rating methods de-rate using correlations based on physical properties and, hence, have a system factor included. In such a case, if de-rating would have been on a system factor basis (as opposed to foaming or uncertainty) additional de-rating may not be required. It should be noted that different proprietary methods may develop their built-in system factors differently. Where two or more de-rating factors are considered applicable, the judgement of the experienced designer is required to decide how these factors may be combined to avoid excessive de-rating. For example, it may be satisfactory to apply only the most conservative of the applicable factors. On the other hand, it may be felt necessary to specify more de-rating than any single consideration would suggest but not as much as would be provided by a de-rating factor that was the product of the contributing factors. FOAMING FACTOR - A foaming factor is the most common type of de-rating factor. The hydraulic capacity of column trays and packings is reduced by the presence of foam. Foaming may induce several consequences: • • • •
filling of the vapor space or packing void spaces with foam excessive liquid entrainment from the active area or packed bed as foam expanded column of liquid entering the downcomer as foam poor vapor disengagement from liquid in the downcomer
For a discussion of the types of foam and effect of foaming on fractionator performance, refer to references 25, 26, and 27. Common causes of foam and/or contributors to foaming are: A. Surface active agents are present. B. Marangoni stabilization of bubbles from the mass transfer process occurs. C. High liquid viscosity inhibits the drainage of the liquid between bubbles or interferes with the escape of the bubbles from the two-phase mixture. D. The fluid is composed of partially miscible components in a single liquid phase close to the plait point. The component about to form a new liquid phase behaves like a surface active agent. E. Small quantities of finely divided solids or very high molecular weight components are present. F. Contaminated salt solutions can foam because of ionic interactions at the interface, e.g. carbonate solutions. Foaming factors used to de-rate the capacity of the column, influence one or more key variables such as: • • • • •
tower area tray spacing downcomer area downcomer type (straight, sloped) packing size and type (structured, random)
Foaming factors normally range from 0.6 to 0.9 depending on the severity of the foam. In extreme cases, factors as low as 0.15 to 0.3 have been necessary. Page 3 of 12
Issued: 09/01/81 Revised: 01/15/1995
DEFINITIONS
0.03
Foaming can be rate sensitive. A system may foam at a particular condition, yet operate without foam t a higher or lower rate. Most of the tray manufacturer's catalogs show foam factors that were originally determined to be required for gas treating processes such as removal of hydrogen sulfide, carbon dioxide and water. These foam factors do not necessarily apply to the production of the pure chemicals (e.g., amines, glycols, ketones) used in the gas treating processes. SYSTEM FACTOR - A system factor is a de-rating factor applied to the capacity correlation for reasons other than foaming. System factors usually relate to extreme values of physical properties of the separation. They are used when designing outside the range of the physical property data bases of empirical design correlations.
It is common practice to determine a system factor when columns consistently fail to meet the capacity predicted for that particular system. The factor may apply to one or more of the key variables such as bubbling area or downcomer area, reflecting the inadequacy of the relevant correlations. It follows that system factors determined in this way are specific to the correlations used in their determination, and may or may not be applicable to other correlations. Common examples of the effects of physical properties are: •
•
low surface tension liquids which produce very fine droplets that can reduce the jet flood capacity; high vapor densities which lessen the gas-disengaging driving forces from the liquid, thus reducing downcomer capacity.
Some of the "reasons" commonly used to apply system factors are: • • • • • • • •
high pressure low temperature vacuum high liquid rate low liquid rate high viscosity low surface tension two liquid phases
In some cases, several of the factors are interrelated or may otherwise be present simultaneously, and should be treated as a single phenomenon. De-rating for the effects of physical properties are often included in proprietary rating methods. The application of system factors is often arbitrary and inconsistent, mainly because the myriad of design and operating variables make an impossible task of identifying the exact cause or effect of the problem when a column floods prematurely. SAFETY FACTOR - Safety factor is applied to account for deviations from a particular correlation's fit from its available data base. Safety factors allow for uncertainty in the application of capacity, pressure drop or efficiency calculations. Presumably, a design correlation is the best fit of the data, excluding safety factor; although in some cases there may be measurement errors such that a particular correlation may not exactly reproduce the data.
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Issued: 09/01/81 Revised: 01/15/1995
DEFINITIONS
0.03
There are a number of reasons for applying a safety factor. Some of these are: • • • • • • •
accuracy and range of applicability of a particular design correlation scatter or standard deviation in the data observations used in the design correlation ignorance of the system properties variations in operating conditions effects of mechanical design variables upon the process rating effect of column control instability upon the system other uncertainties
The safety factor is chosen carefully with due consideration of the value of the investment and the degree of risk. A greater margin of safety is often applied to unproven systems or devices, and/or when the consequence of failure is dire. For further discussion, refer to the FRI Tray Design Handbook, Volume 1, Section 5.2, pages 1 and 14. MANHOLE (VESSEL MANHOLE) - A vessel manhole permits column access. A manhole is an external opening that pierces the pressure vessel, allowing entry into the column for equipment installation, internal maintenance, and column inspection. The typical size is 18" to 24" nominal pipe diameter. Larger sizes are often used; some are elliptical or rectangular shapes.
Normally there are external platforms and ladders giving easy access to the elevation of each manhole. See Section 3.02; "Designing for Maintenance". A manhole is sealed with a removable, bolted-on cover plate. to assist in safe removal, a davit or hinge is usually provided as a part of the manhole assembly. See drawing of vessel manhole entry nozzle with manhole cover and davit ( Figure 1a). Manhole covers may be hinged as in Figure 1b. MANWAY (TRAY MANWAY) - A manway permits workman passage through equipment partitions. See Section 1.14; "Tray Construction and Assembly".
A tray manway is a removable panel section in the fractionating tray which provides an opening through the deck allowing passage to adjacent sections within the column tray spacings for maintenance and inspection. Tray manway sizes vary to suit the user specifications as well as the mechanical design constraints of each specific tray layout. A typical manway opening is 16" X 24". See Section 3.02; "Designing for Maintenance". Tray manways are usually designed to be easily removable from either above or below each tray. In some cases the manway may be removed only from one direction. On some collector trays, the chimney risers are large enough to permit manway access by removing the hats. Manway clamps are special fasteners that allow the workman to open or close the manway from either the top side or underneath the tray. ANTI-JUMP BAFFLES - Anti-jump baffles are vertical baffles suspended at the centerline and along the full length of the downcomer entrance to form a partition that deflects the frothy liquid into the downcomer.
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Issued: 09/01/81 Revised: 01/15/1995
DEFINITIONS
0.03
Anti-jump baffles are often used above the intermediate (center and/or off-center) downcomer entrance areas on all types of multi-pass cross-flow trays (bubble-cap, sieve, valve, etc.) to help achieve optimum tray capacity (Figures 2a and 2b). In principle, vapor expansion near the outlet weir "pumps" liquid over the weir. At sufficiently high vapor rates, the trajectory carries some liquid completely over most downcomers and onto the opposite active area. This recycle of liquid will prematurely flood the tray unless anti-jump baffles are used. Because these baffles are used only on multi-pass trays, these are typically high liquid rate applications. SPLASH BAFFLES - Splash baffles are vertical solid baffle plates placed as shield on the active area side of the overflow weir, parallel to the weir, with a clearance from both deck and weir ( Figure 3).
Splash baffles are used only in very low liquid rate service to prevent liquid from being "blown" over the overflow weir as a spray. These baffles effectively retain low liquid volumes on the active area of the tray so that the tray can function in the "spray" regime without blowing "dry". See Section 1.16, "Low Liquid Rate Designs". There are several different types of splash baffles. (49) Hooded splash baffles are similar to vertical baffles, except they are sloped away from the active area toward the downcomer in order to cover the whole are of pipe or envelope downcomers ( Figure 4). Hooded splash baffles are frequently used on cartridge trays which use envelope downcomers. Because these types of baffles create restrictions to liquid flow, they should be used only for low liquid rates. Also see Picket Fence Weirs. (49) PICKET FENCE WEIRS (BAFFLES) - Picket fence weirs (Rectangular Slot Overflow Weirs) are rectangular plates located at selected intervals along the weir, and extending vertically above the weir, in such a manner that the desired effective shorter weir length is achieved ( Figures 5a and 5b). The vertical, rectangular slot is less affected by weir out-of-levelness than are vee-notches; therefore, slots are preferred.
Picket fence weirs are used for two purposes in low liquid rates to retain a sufficient liquid depth on the tray. 1. They shorten the effective net weir length to produce a greater height over the weir. 2. They are used as partial splash baffles when designed to extend at least half a tray spacing above the active tray deck. Picket fence weirs can be used at all liquid rates as a flow control device to preferentially direct the liquid into a specific downcomer. Normally, these are applied on three or more passes. SEAL PANS AND SUMPS - Downcomer seal pans are the most common method for sealing the bottom tray of each set of column trays ( Figure 6).
Draw-off sumps are commonly used for an intermediate liquid draw-off from a trayed column ( Figure 7). See Section 1.05-2, "Partial Liquid Draw-offs". Inlet sumps, ( Figure 8), also called inlet seal pans, may be used for two reasons:
Page 6 of 12
Issued: 09/01/81 Revised: 01/15/1995
DEFINITIONS
0.03
1. To reduce the downcomer exit head loss in high liquid rate service. This allows a positive downcomer seal with low weir height settings, which in turn reduces the downcomer backup for greater capacity. This is often applied in high pressure service. 2. To provide a positive downcomer seal for all liquid rates, particularly low liquid rate service. When the downcomer clearance is set below the tray floor, a minimum amount of liquid is required to seal the downcomer. This improves low liquid rate column start-up and operation. This is often applied in vacuum service. Designers should be aware that inlet sumps can be prone to fouling (see Section 3.03). Sumps can create potential flow restrictions between the sump bottom and the outlet weir below.
Page 7 of 12
Issued: 09/01/81 Revised: 01/15/1995
DEFINITIONS
Figure 1a. MANHOLE COVER WITH DAVIT
Page 8 of 12
0.03
Issued: 09/01/81 Revised: 01/15/1995
DEFINITIONS
Figure 1b. MANHOLE COVER WITH HINGE
Page 9 of 12
0.03
Issued: 09/01/81 Revised: 01/15/1995
DEFINITIONS
Figure 2a. ANTI-JUMP BAFFLE (ISOMETRIC VIEW)
Figure 2b. ANTI-JUMP BAFFLE (ELEVATION VIEW)
Page 10 of 12
0.03
Issued: 09/01/81 Revised: 01/15/1995
DEFINITIONS
Figure 3. HOODED SPLASH BAFFLE
Figure 4. VERTICAL SPLASH BAFFLE
Figure 5a. PICKET FENCE WEIR (BAFFLE)
Figure 5b. PICKET FENCE WEIR (BAFFLE)
Page 11 of 12
0.03
Issued: 09/01/81
DEFINITIONS
Revised: 01/15/1995
Figure 6. DOWNCOMER SEAL PAN
0.03
Figure 7. DRAWOFF SUMP
Figure 8. INLET SUMP (INLET SEAL PAN)
Page 12 of 12
FRI VOLUME 5: FRACTIONATION DESIGN HANDBOOK
REFERENCES
Issued: Revised:
03/31/1987
0.04
01/15/1998
REFERENCES
REFERENCES ............................................................................................................................................ 1 References ................................................................................................................................................... 2 Unreferenced Publications ..................................................................................... ..................................... 7
Issued: 03/31/87 Revised: 01/15/98
1
REFERENCES
0.04
References
1. Jacobs, J.K., "Reboiler Selection Simplified", Hydrocarbon Processing and Petroleum Refiner, Vol. 40, No.7, July, 1961, pp. 189-196. 2. Keller, J.D., "The Manifold Problem:, Trans. ASME, 71, 1949, pp. 77-85. 3. Senecal, V.E., "Fluid Distribution in Process Equipment", Ind. Eng. Chem., 49, No. 6, June 1957, pp. 993-997. 4. Simpson, L.L., "Process Piping-Functional Design", Chemical", Chemical Engineering, April 14, 1969, pp. 167-181. 5. Zenz, F.A., "Minimize Manifold Pressure Drop", Hydrocarbon Processing and Petroleum Refiner, Vol. 41, No. 12, December 1962, pp. 125-130. 6. VanDerhegge Zigen, B.G., "Flow Through Uniformly Tapped Pipes", Applied Science Res., A3, 1951, pp.144-162. 7. Shah, G.C., "Troubleshooting Distillation Columns", Chemical Engineering, July 31, 1978, pp. 70-78. 8. Anderson, A.E., and Jubin, J.C., "Applied Distillation-Case Histories", Chemical Engineering Progress, Volume 60, No. 10, October, 1964, pp. 60-63. 9. Love, F.S., "Troubleshooting Distillation Problems", Chemical Engineering Progress, Volume 71, No. 6, June, 1975, pp. 61-64. 10. Liberman, N.P., "Checklist is the key to dealing with distillation troubles", Oil & Gas Journal, September 10, 1979, pp. 121-125. 11. McLaren, D.B., and Upchurch, J.C., "Guide to Trouble-Free Distillation", Chemical Engineering, June 1, 1970, pp. 139-152. 12. Billet, R., Distillation Engineering, Chemical Publishing Co., New York, NY, 1979. 13. FRI Progress Report, November, 1976. 14. FRI Topical Report No. 82, November 15, 1978. 15. FRI Design Volume 1, Section 5.2, page 9, Figure 4. 16. FRI Progress Report, July-August, 1981. 17. AIChE Equipment Testing Procedures Committee, "AIChE Equipment Testing Procedure: Tray Page 2 of 7
Issued: 03/31/87 Revised: 01/15/98
REFERENCES
0.04
Distillation Columns - A Guide to Performance Evaluation", 2nd Edition, 1986. 18. Buckley, P.S., "Material Balance Control in Distillation Columns", AIChE Workshop-Industrial Process Control, Tampa, FL, Nov. 11-13, 1974. 19. Kister, H.Z., "Outlets and Internal Devices for Distillation Columns", Chemical Engineering, July 18, 1980, pp. 79-83.uncertainty (safety factor). 20. Lieberman, N., "Instrumenting a Plant to R un Smoothly", Chemical Engineering, Sept. 12, 1977, p. 140. 21. Standiford, F.C., "Effect of Non-condensibles on Condenser Design and Performance", Chemical Engineering Progress, 75 (7), 59, 1979. 22. FRI Progress Report, May-June, 1986. 23. Thrift, G.C., "How to Specify Valve Trays", Petroleum Refiner, Vol. 39, No. 8, Aug. 1960, pp. 93-94. 24. FRI Progress Report, Jan-Feb, 1981. 25. FRI Design Volume 1, Section 5.2, page 5. 26. Zuiderweg, F.J., "Flow Regimes, Tray Efficiency and Downcomer Capacity Limitations by Foaming", FRIConsultant's Report, November 20, 1981. 27. Perry, R.H., and Green, D.W., "Perry's Chemical Engineers' Handbook", 6th Edition, McGrawHill, 1984. 28. AIChE Equipment Testing Procedure. Tray Distillation Columns. A Guide to Performance Evaluation 2nd Edition, 1987. 29. AIChE Equipment Testing Procedure. Packed Columns. A Guide to Performance Evaluation. 2nd Edition1990. 30. FRI Topical Report No. 50, November 20, 1970. 31. Kunesh, J.G., Lahm, L.L., and Yanagi, T., "Commercial Scale Experiments That Provide Insight on Packed Tower Distributors", Ind. Eng. Chem. Res., Vol. 26, 1987, p. 1845. 32. McMullan, B.D., Ravicz, A.E., and Wei, S.J., "Troubleshooting a Packed Vacuum Column", AIChE National Meeting, November, 1990. 33. Perry, D., Nutter, D.E., and Hale, A., "Liquid Distribution for Optimum Packing Performance", Chem. Engr. Progress, January, 1990. Page 3 of 7
Issued: 03/31/87 Revised: 01/15/98
REFERENCES
0.04
34. Albright, M.A., "Packed Tower Distributors Tested", Hydrocarbon Processing, Sept., 1984, p. 173. 35. Hoek, P.J., Wesselingh, J.A., and Zuiderweg, F.J., "Small Scale and Large Scale Liquid Maldistribution in Packed Columns", Chem. Eng. Res. Des., Vol. 64, Nov., 1986, p. 431. 36. Fadel, T.M., "Selecting Packed-Column Auxiliaries", Chemical Engineering, Jan. 23, 1984, p. 71. 37. Harrison, M.E., and France, J.J., "Distillation Column Troubleshooting Part 2 Packed Columns", Chemical Engineering, April, 1989. 38. Muir, L.A., and Briens, C.L., "Low Pressure Drop Gas Distributors for Packed Distillation Columns", The Canadian Journal of Chemical Engineering, Vol. 64, Dec., 1986, p. 1027. 39. Perry, R.H., and Green, D., Perry's Chemical Engineers' Handbook, 6th Edition, p. 5-48 & 49. 40. Porter, K.E., and Ali, Q.H., "Gas Distribution in Packed Columns". Based on Ph.D Thesis "Gas distribution in shallow large diameter packed beds", Q.H. Ali, University of Aston, 1984. 41. Pro Pak Bulletin No. 23. 42. Stikkelman, R.M., and Wesselingh, J.A., "Liquid and Gas Flow Patterns in Packed Columns", Distillation and Adsorption 1987, European Federation of Chemical Engineering, Publication No. 62. 43. Zens, F.A., "Minimizing Manifold Pressure Drop", Petroleum Refiner, Dec., 1962, p. 125. 44. Greskovich, E.J., and O'Bara, J.T., "Perforated-Pipe Distributors", L. & E.C. Process Design and Development, Vol. 7, No. 4, October, 1968, p. 593. 45. Mansfield, E., "Statistics for Business and Economics", Norton & Co., New York, 1983. 46. York, Otto, "Performance of Wire Mesh Demister", CEP, August, 1954. 47. Warner, B.J., and Scauzillo, F., "Design Considerations of Fibrous Filters for Mist Elimination", Socony Mobil Oil Company, paper presented at the Gas Conditioning Conference, University of Oklahoma, 1963. 48. "Fleximesh Design Manual", Divmet Division, Koch Engineering Company. 49. Kister, H.Z., "Distillation Operation:, McGraw-Hill, New York, 1990, p. 91. 50. Karrasik, I., Pump Seminar, Kingsport, Tennessee, 1989. 51. Patterson, F.M., "Vortexing Can Be Prevented in Process Vessels and Tanks," Oil & Gas Journal, Page 4 of 7
Issued: 03/31/87 Revised: 01/15/98
REFERENCES
0.04
Aug. 4, 1969. p. 118. 52. Waliullah, S., "Do-It Yourself Vortex Breakers," Chemical Engineering, May 9, 1988, p. 108. 53. Chien, H.Y., "Rigorous Method for C alculating Minimum Reflux Rates in Distillation," AIChE Journal, 24(4), 606, 1978. 54. Henley, E.J., and Seader, J.D., "Equilibrium-Stage Separation Operations in Chemical Engineering", John Wiley & Sons, New York, 1981. 55. FRI Handbook, Vol. 1, Section 3.4, p. 10. (Dualflow Safety Factor). 56. FRI Handbook, Vol. 1,Section 4.2, p.2. (Bubble Cap Safety Factor). 57. FRI Handbook, Vol. 1, Section 5.2, pp.1-4,12,14. (Sieve Tray Safety Factor). 58. FRI Handbook, Vol. 1, Section 5.5, p.5. (Sieve Tray Weeping - Reliability). 59. Ruff, K., Pilhofer, T., and Mersmann, A., "Ensuring Flow Through All the Openings of Perforated Plates for Fluid Dispersion," Int. Chem. Eng., 18(3), p. 395, 1978. 60. Glitsch, Ing., "Ballast Tray Design Manual," Bulletin No. 4900, 6th Edition, 1993. 61. "Flexitray Design Manual", Koch Engineering Company Bulletin 960-1, 1982. 62. Norton Tray Design Manual, to be published. 63. Nutter Float Valve Design Manual, Rev. 1, August 1981. 64. FRI Handbook, Vol. 2, Section 8.2, p. 2. (Packing Efficiency Accuracy). 65. Frank, O., Chemical Engineering, March 14, 1977, p. 110. 66. Porter, K.E., and Jenkins, J.D., I.Chem.E. Symp. Ser. 56, Summary Paper, London, 1979. 67. Kister, H.Z., "Distillation Design", McGraw-Hill, New York, 1991. 68. FRI Handbook, Vol. 2, Section 8.1, pp. 4-5. (Packed Column Safety Factor). 69. FRI Handbook, Vol. 2, Section 8.5. (Packing Correlation Data Comparisons). 70. FRI Topical Report No. 47. (Packing Correlation Data Comparisons). 71. Strigle, R.F. Jr., "Random Packings and Packed Towers Design and Application", Gulf Publishing, Houston, 1987. Page 5 of 7
Issued: 03/31/87 Revised: 01/15/98
REFERENCES
0.04
72. Nutter Engineering Co., "Package Trays for Pipe-Size Process Vessels," Bulletin PT-1. 73. Nutter, I.E., "Self-Sealing Pre-Assembled Fluid Contact Tray Unit,", US Patent No. 3,179,389, April 20, 1965. 74. Simpson, L.L., "Sizing Piping for Process Plant," Chemical Engineering, June 17, 1968, p. 204. 75. U. S. Patent Number 4,820,455, date April 11, 1989. 76. Zuiderweg, F. J., P. J. Hoek, and L. Lahm, Jr., "The Effect of Liquid Distribution on the Separating Efficiency of Packed Columns", I. Chem. E. Symposium Series No. 104, 1987, p. A217-A231. 77. European Patent Application Number 0 364 117 A2, Date Sept. 21, 1989. 78. Kurtz, D. P., K. J. McNulty, R. D. Morgan, "Stretch the Capacity of High-Pressure Distillation Columns", Chemical Engineering Progress, February 1991, p. 43-49. 79. Fulmer, J. W. and K. C. Graf, "Distill Acetone in Tower Packing", Hydrocarbon Processing, October 1991, p. 87-91.1 80. Lieberman, N. P. Process Design for reliable Operation, 2d. ed., Gulf Publishing, Houston, Texas, 1988. 81. Rukovena, F. and T. D. Koshy, "Packed Distillation Tower Hydraulic Design Method and Mechanical Considerations", Advance copy, Approved for Publication in Industrial and Engineering Chemistry Research, 1993. 82. Eckert, J. S. , "Design of Packed Columns," in P. A. Scweitzer (ed.) Handbook of Separation Techniques for Chemical Engineers, McGraw-Hill, New York 1979, p. 1-221 - 1-240. 83. Groenhof, H. C., "Scaling Up of Packed Columns - Part I," The Chemical Engineering Journal, 14(1977) p. 181-191. 84. See for example: Zuiderweg, F. J., Topical Report No. 92, "Packed Columns: Flow Phenomenon and Performance", July 20, 1984. 85. Zuiderweg, F. J., J. G. Kunesh, and D. W. King, "A Model for the Calculation of the Effect of Maldistribution on the Efficiency of a Packed column", Trans IChemE, Vol. 71 Part A, January 1993, p. 38-44. 86. Nawrocki, P. A., Z. P. Xu, and K. T. Chuang, "Mass Transfer in Structured Corrugated Packing", The Canadian Journal of Chemical Engineering, Vol. 69, December 1991, p. 1336- 1343. 87. Thompson, L. "Does a Column Composition Profile that is Concave Up Indicate Something Other Than a Distribution Problem?", FRI Technical Committee Correspondence, May 1993. Page 6 of 7
Issued: 03/31/87 Revised: 01/15/98
REFERENCES
0.04
88. Perry, R.H. & D.W. Green, eds, "Perry's Chemical Engineering Handbook", 6th Edition, McGraw-Hill Book Company, New York (1984). 89. Hepp, P.S., "Internal column reboilers - liquid level measurement," Chemical Engineering Progress, Volume 59, No. 2, February, 1963. 90. Simpson, L.L., “Sizing Piping for Process Plants,” C hemical Engineering, June 17, 1968, p. 204. 91. Brierley, R.J.P., P.J.M. Whyman and J.B. Erskine, "Flow Induced Vibration of Distillation and Absorption Column Trays," I. Chem. E. Symp. Ser. 56, 1979, p. 2.4/45. 92. Winter, J.R., "Avoid Vibration Damage to Distillation Trays," Chemical Engineering Progress, May 1993, page 42. 93. Shiveler, G.H., "Use Heavy-Duty Trays for Severe Services," Chemical Engineering Progress, August 1995, pages 72-81. 94. Chen, G.K., “Troubleshooting Distribution Problems in Packed Columns”, The Chemical Engineer Supplement, September 1987, pp. 10-13. 95. Technical Paper 410, Crane Company, New York, 1981. 96. Tuve, G.L. and R.E. Sprenkle, “Orifice Discharge Coefficients for Viscous Liquids”, Instruments, 6, pp. 201-206, 1933. 97. FRI Topical Report No.115, June 15, 1994. 98. FRI Topical Report No. 122, July 30, 1996. 99. FRI Topical Report No. 118, February 15, 1995. 100. Hasbrouck, et al. Chemical Engineering Progress, March, 1993, pp. 63-72.
2
Unreferenced Publications
a. Koch Engineering Bulletin 570, "Fleximesh Mist Eliminators". b. Glitsch Bulletin 332, "Glitsch Mist Eliminators". c. York Bulletin 55, "Mist Eliminators". d. Koch Engineering Bulletin KME-12, "Mist Eliminators". e. FRI Design Practices Manual, Vol. 5, Section 1.05. f. McDuffie, N.G., "Vortex Free Downflow in Vertical Drains".
Page 7 of 7
FRI VOLUME 5: FRACTIONATION DESIGN HANDBOOK
READING LIST
Issued: Revised:
01/15/1992
0.05
01/15/1996
READING LIST
READING LIST ....................................................................................... .................................................. 1 1.
Introduction ............................................... ........................................................................................... 2
Issued: 01/15/92 Revised: 01/15/96
1
READING LIST
0.05
Introduction
The reading list below gives references for a number of fractionation-related topics. The material is primarily intended to serve inexperienced engineers and stresses fundamental understanding and up-todate guidance in a number of areas. This reading list is a select set of particularly useful references rather than a comprehensive literature search. The method used for this selection was first to ask the FRI membership to submit references which they found useful in the design, operation or troubleshooting of fractionation equipment. The members of the DPC then voted on each proposed item. A precis follows each reference. A number of the books also give extensive lists of references. These include references Ki1 and Ki2 (Kister) and Lo1 (Lockett). Many of the topics listed here are also discussed in the Design Practices Handbook or elsewhere in the FRI literature. References for FRI materials are not repeated here. This list will be periodically updated as additional references are submitted. References may be submitted to any member of the Design Practices Committee.
Page 2 of 9
Issued: 01/15/92
READING LIST
Revised: 01/15/96
TOPIC
0.05
REFERENCE NUMBERS
BATCH DISTILLATION
EL1
CONTROL
Bu1, Lo1, Sh2
FOAMING
Ro1
HEAT TRANSFER
Fa1
MAINTENANCE
Ma1
PACKED TOWERS
General Internals Liquid Distiribution Random Packings Vapor Distribution
Ki1, Ki2, Ku1, St1 Ch1 Ku2, Mo1, Pe1, Se1, Ze1, Zu1 St1 Mu1
SIMULATORS
Be1
STARTUP
Dr1
TRAYED TOWERS
Baffle Tray Bubble Cap Tray Chimney Tray Sieve Tray General Clear Liquid Height Entrainment Flow Regime Weeping Tray Damage Valve Tray General Weeping Vibration TROUBLESHOOTING
Page 3 of 9
Le1 Bo2 Wh1 Ki1, Ki2, Lo1 Co1 Ki3 Ho1 Hs1, Lo2 El2 Bo1, Gl1, Ki1, Ki2, Ko1, Lo1, Nu1 Hs1, Lo2 Br2
Issued: 01/15/92 Revised: 01/15/96
READING LIST
0.05
Ref. No. Be1
Bennett, D.L., and K. A. Ludwig, "Understand the Limitations of Air/Water Testing of Distillation Equipment," Chem. Eng. Prog. 90(4), 1994, p. 72. Air/water testing is one technique to model the behavior of distillation trays and packings. This article provides guidance on how to assess the value and limitations of such tests.
Bo1
Bolles, W.L., "Estimating Valve Tray Performance," Chem. Eng. Prog., 72(9), 1976, p. 43. Valve tray performance is estimated from sieve tray data using a valve tray-sieve tray analogy.
Bo2
Bolles, W.L., "Optimum Bubble-Cap Tray Design," Petr. Proc., Feb. 1956, p. 65; March, 1956, p. 82; April, 1956, p. 72; May, 1956, p. 109. This is a classic series of articles which discusses the design of bubble caps, bubble cap arrangement and general tray layout. Although they are not recent articles, they continue to be widely used.
Br1
Bravo, J., “Effectively Fight Fouling of Packing,” Chem. Eng. Prog., 89(4), April 1993, p. 72.
Br2
Brierley, R.J.P., P.J.M. Whyman and J.B. Erskine, "Flow Induced Vibration of Distillation and Absorption Column Trays," I. Chem. E. Symp. Ser., 56, 1979, p. 2.4/45. A model is developed to predict the process conditions under which vibration may be expected. Tray failure is likely when the oscillation frequency of the process fluids coincides with the naturalfrequency of the tray structure. A procedure is proposed which is particularly useful for solving problems in existing columns.
Bu1
Buckley, P. S., W. L. Luyben and J. P. Shunta, "Design of Distillation Column Control Systems," Instrument Society of America, Research Triangle Park, NC, 1985. This book provides a practical guide to typical distillation controls including reboiler, condenser, composition, sidedraws, feed forwards and overrides. The latter part provides quantitative mathematical models for the design of such schemes.
Ch1
Chen, G.K., "Packed Column Internals," Chem. Eng., March 5, 1984, p. 40. A comprehensive review of all the internals that are required in a packed column.
Co1
Colwell, C.J., "Clear Liquid Height and Froth Density on Sieve Trays," Ind. Eng. Chem. Process Des. Dev., 20, 1981, p. 298. Correlations for clear liquid height and froth density on sieve trays are presented. The correlations are based on a diverse set of experimental data including both air/water and hydrocarbon systems. These correlations are especially useful in calculating tray residence time, pressure drop and efficiency.
Page 4 of 9
Issued: 01/15/92 Revised: 01/15/96
READING LIST
0.05
Ref. No. Dr1
Drew, J. W., "Distillation Column Startup," Chem. Eng., Nov. 14, 1983, p. 221. Common causes of startup problems are discussed, along with a multitude of useful ideas for preventing and overcoming them. Several case studies are briefly mentioned. Illustrated are preparation and use of a table which links possible trouble conditions to their probable causes and recommended corrective action.
El1
Ellerbe, R. W., "Batch Distillation," in P. A. Schweitzer (ed.) Handbook of Separation Techniques for Chemical Engineers, McGraw-Hill, New York, 1979, p. 1-147. This is a practical guide to batch distillation strategies and shortcut calculation methods. Addressed are distillation curves, constant and variable reflux operation, total reflux. A brief discussion on control and troubleshooting is included.
El2
Ellingsen, W.R., "Diagnosing and Preventing Tray Damage in Distillation Columns," DYCORD 86, IFAC proceedings of International Symposium on Dynamics and Control of Chemical Reactors and Distillation Columns, Bournemouth, U.K., Dec. 8-10, 1986. This paper discusses a review of tray damage incidents at a large chemical company and notes that the majority of these problems are caused by high liquid levels in the bottom of the column. The mechanical reasons for the cause of tray damage and preventing it are discussed.
Fa1
Fair, J.R., "Designing Direct-Contact Coolers/Condensers," Chem. Eng., June 12, 1972, p. 91. This article contains detailed design procedures including worked examples for sizing trayed and packed columns for all types of direct contact heat transfer services.
Fo1
Gl1
Foucher, Coherty, Malone, “Automatic Screening of Entrainers for Homogenous Azeotropic Distillation”, I&EC Res. 30, 1991, p. 760. Glitsch, Inc., "Ballast Tray Design Manual," 4th ed., Bulletin No. 4900, Dallas, Texas, 1974. This is Glitsch's design manual for their proprietary valve trays. It includes capacity and pressure drop correlations, criteria for downcomer design and general design guidelines.
Ha1
Harrison, M.E., and J.J. France, "Troubleshooting Distillation Columns," Chem. Eng., March, 1989, p. 116; April, 1989, p. 121; May, 1989, p. 126; and June, 1989, p. 139. This is a 4 part review on troubleshooting including: Part 1-techniques and tools, signs of flooding; Part 2-common packed tower problems; Part 3-common trayed tower problems; and, Part 4- problems with tower auxiliaries (reboilers are emphasized).
Ho1
Hofhuis, P.A.M., and F.J. Zuiderweg, "Sieve Plates: Dispersion Density and Flow Regimes," I. Chem. E. Symp. Ser., 56, 1979, p. 2.2/1. Experimental two-phase density profiles were determined for a variety of sieve tray designs. Four distinct flow regimes were identified along with the corresponding effects on hydrodynamic behavior such as holdup and flooding.
Page 5 of 9
Issued: 01/15/92 Revised: 01/15/96
READING LIST
0.05
Ref. No. Hs1
Hsieh, C.-L., and K. J. McNulty, "Predict Weeping of Sieve and Valve Trays," Chem. Eng. Prog. 89(7), 1993, p. 71. A model to quantitatively predict weeping on sieve and valve trays is proposed, and the general validity of the model is demonstrated with public-domain and in-house-developed data.
Ki1
Kister, H.Z., Distillation Operation, McGraw-Hill, New York, 1990. This book provides a practical guide to distillation including operation, troubleshooting, field-tested cures, and design techniques. Numerous case histories describe lessons learned from real problems.
Ki2
Kister, H.Z., Distillation Design, McGraw-Hill, New York, 1992. This book offers a practical and thorough discussion of all the considerations needed to effectively design fractionation systems and to design and select fractionation equipment.
Ki3
Kister, H. Z., W. V. Pinczewski and C. J. D. Fell, "Entrainment from Sieve Trays Operating in the Spray Regime," Ind. Eng. Chem. Proc. Des. Dev., 20(3), 1981, p. 528. The effects of tray spacing, weir height, hole diameter, fractional hole area and of liquid and vapor velocities on sieve tray entrainment in the spray regime are reported. This study also lays foundations to an entrainment correlation later reported by Kister and Haas.
Ko1
Koch Engineering Company, Inc., "Design Manual - Flexitray," Bulletin 960-1, Wichita, Kansas, 1982. This is Koch's design manual for their proprietary valve trays. It includes capacity and pressure drop correlations, criteria for downcomer design and general design guidelines.
Ku1
Kunesh, J.G., "Practical Tips on Tower Packing," Chem. Eng., December 7, 1987, p. 101. Choosing packing size, selecting packing material, defining loading and flooding, ordering the correct volume of packing, and column internals are discussed in connection with changing a trayed tower to a packed tower.
Ku2
Kunesh, J.G., L.L. Lahm and T. Yanagi, "Controlled Maldistribution Studies on Random Packings at a Commercial Scale," I. Chem. E. Symp. Ser. 104, 1987, p. A233. The sensitivity of random packing performance to the quality of liquid distribution and controlled maldistribution in a 4-foot diameter column is shown. The results provide qualitative guidelines for the design of distributors.
Ku3
Kunesh, J.G., H. Kister, M. Lockett, and J. Fair, “Gamma Scan Evaluation for Distillation Columns”, Chem. Eng. Prog., March 1990, p. 37.
Le1
Lemieux, E.J., "Data for Baffle Tray", Hydrocarbon Processing, September, 1983, p. 106. Experimental air-water capacity and pressure drop data for a variety of segmental and shower deck baffles are reported. Comparisons are made with capacity data from commercial FCCU fractionator desuperheating service. Page 6 of 9
Issued: 01/15/92 Revised: 01/15/96
READING LIST
0.05
Ref. No. Li1
Lieberman, N.P., Process Design for Reliable Operations, 2nd ed. Gulf Publishing, Houston, Texas. 1988. This book provides practical process design guidelines based on the author's extensive field experience. Several chapters deal with distillation equipment.
Li2
Lieberman, N.P., Troubleshooting Process Operations, 3rd ed., PennWell Publishing, Tulsa, OK, 1991. This book discusses lessons from the author's troubleshooting experiences and includes checklists for a number of tower problems.
Lo1
Lockett, M.J., Distillation Tray Fundamentals, C ambridge University Press, Cambridge, England, 1986. This book contains an in-depth treatment of distillation tray fluid dynamics and efficiency, with emphasis on sieve and valve trays.
Lo2
Lockett, M.J., and S. Banik, "Weeping from Sieve Trays," Ind. Eng. Chem. Proc. Des. Dev., 25, 1986, p. 561. This is a study of liquid weeping from rectangular sieve trays using the air-water and the air-isopar systems in a hydraulic simulator. The data was taken at atmospheric pressure.
Lu1
Luyben, W. L. (ed.), "Practical Distillation Control," Van Nostrand Reinhold, New York, 1992. This book is a collection of academic and industrial articles focusing on advanced control techniques and their applications. Multivariable controls, inferential model controls, dynamic simulation and expert systems are addressed. Case studies include challenging applications such as superfractionators, vapor recompression, heat integrated columns, extractive distillation and batch distillation.
Ma1
Manifould, D., "Traying Towers: Planning and Techniques Can Be Vital," Oil & Gas Journal, June 18, 1973, p. 65. A practical guide to tray installation and maintenance. Includes maintenance and inspection checklists which are important resources for determining when tray replacement is needed. Contains useful guidelines for tray installation including turnaround planning, manpower requirements and proper sequencing.
Mo1
Moore, F., and F. Rukovena, "Liquid and Gas Distribution in Commercial Packed Towers," Paper presented at the 36th Canadian Chemical Engineering Conference, October 5-8, 1986; same paper published in Chemical Plants and Processing (European Edition), August, 1987, p. 11. This paper discusses the importance of liquid and gas distribution in packed tower design as well as some fundamental design relations for liquid and gas distributors. The concept of distribution quality is introduced and several cases are reported which show the separation improvement possible on replacing low-quality distributors with high-quality distributors.
Page 7 of 9
Issued: 01/15/92 Revised: 01/15/96
READING LIST
0.05
Ref. No. Mu1
Muir, L.A., and C.L. Briens, "Low Pressure Drop Gas Distributors for Packed Distillation Columns," Can. J. Chem. Eng. 64, 1986, p. 1027. Gas velocity profiles were measured for various gas distributors in a scale model of the gas distribution chamber of a distillation column.
Nu1
Nutter Engineering, "Float Valve Design Manual," Tulsa, Oklahoma, 1981. This is Nutter's design manual for their proprietary valve trays. It includes capacity and pressure drop correlations, criteria for downcomer design and general design guidelines.
Pe1
Perry, D., D.E. Nutter and A. Hale, "Liquid Distribution for Optimum Packing Performance", Chem. Eng. Prog., Jan. 1990. Distributor design criteria and selection guidelines are reviewed with emphasis on distributor flow testing. Statistical analysis of data on commercial distributors provides the basis for flow test sampling guidelines and acceptance criteria.
Ro1
Ross, S., "Mechanisms of Foam Stabilization and Antifoaming Action," Chem. Eng. Prog. 63(9), 1967, p. 41. The chemistry of foam formation is discussed in depth. The required chemical properties of antifoam for both aqueous and nonaqueous systems are discussed as are several cases of industrial foaming problems which were resolved.
Se1
Senecal, V.E., "Fluid Distribution in Process Equipment," Ind. Eng. C hem., 49(6), 1957, p. 93 3. This article contains a fundamental analysis of liquid distribution in perforated pipe and slot-type distributors.
Sh1
Shah, G.C., "Troubleshooting Distillation Columns," Chem. Eng., July 31, 1978, p. 70. A good coverage providing valuable insight into overhead systems, reboilers and tower problems.
Sh2
Shinskey, F.G., "Distillation Control for Productivity and Energy Conservation," 2nd ed., McGraw-Hill, New York, 1984. A practical text dealing with the operation of columns so as to increase production and reduce fuel consumption. Emphasizes the multivariable nature of the distillation control problem but does not overlook the characteristics and limitations of the actual equipment used in distillation.
Sh3
Shiveler, G.H., “Use Heavy Duty Trays for Severe Services,” Chem. Eng. Prog., August 1995, p. 72.
Sl1
Slolely, M., “Subdue Solids in Towers,” Chem. Eng. Prog., 91(1), January 1995, p. 64.
Sl2
Slolely, M. and S. Golden, “Why Towers do not Work,” AIChE Spring meeting, March, 1995, Summarised in Chem. Eng. Prog. 91(5), May 1995, p. 7.
Page 8 of 9
Issued: 01/15/92 Revised: 01/15/96
READING LIST
0.05
Ref. No. St1
Strigle, R.F., Jr., Random Packings and Packed Towers, Gulf Publishing, Houston, Texas, 1987. This book provides an extensive discussion of packed tower design and applications including: hydraulics, gas absorption, liquid stripping, distillation, liquid-liquid extraction and packed tower internals. One shortcoming is the omission of data on packings other than those by the author's company (Norton).
Wh1
Wheeler, D.E., "Design Criteria for Chimney Trays," Hydrocarbon Proc., 47(7), 1968, p. 119. One of the few references that provides a practical guide for determining theresidence time on a chimney tray under various design conditions.
Ze1
Zenz, F. A., "Minimize Manifold Pressure Drop," Hydrocarbon Processing and Petroleum Refiner 41(12), 1962, p.125. The laws of conservation of energy are applied to develop equations for calculating the approximate flow distribution in manifolds and branched piping systems using hand calculations.
Zu1
Zuiderweg, F.J., P.J. Hoek and L. Lahm, Jr., "The Effect of Liquid Distribution and Redistribution on the Separating Efficiency of Packed Columns," I.Chem. E. Symp. Ser., 104, 1987, p. A217. The effect of large-scale maldistribution in packed beds is modelled using a combination of a radial liquid flow model and a zone-stage mass transfer model. This model can predict the effects of relative volatility, concentration, reflux ratio, packing size, column diameter, bed height and redistribution ratio on efficiency.
Page 9 of 9
FRI VOLUME 5: FRACTIONATION DESIGN HANDBOOK
INDEX
Issued: Revised:
11/01/1988
0.06
03/24/2011
INDEX
INDEX ........................................................................................................................................................ 1 1.
Index................................................... ............................................................. ..................................... 2
Issued: 11/01/88 Revised: 03/24/11
1
INDEX
Index
Assembly of Trays: 1.14.1 Bed Limiters and Holddown Plates: 2.03 Blanking of Trays: 1.11 Cartridge Trays: 1.19 Case Study – 1. Packed Column Troubleshooting: 4.50.01 2. An Intermediate Liquid Drawoff Problem: 4.50.02 3. How to Design an FRI Small Scale Column: 4.50.03 Committee, Design Practices: 0.01 Condensers: 4.03.2 Construction of Trays: 1.14.1 Datasheets Packing: 2.07 Trays: 1.17 Definitions: 0.03 Common Terms: 5.01.05 De-rating Factors – Trayed Columns: 1.20 Packed Columns: 2.10 Designing for Ease of Installation: 3.04 Designing Fractionation Systems to Aid Maintenance: 3.02 Dimensional Tolerances: 3.08 Distillation Tower Start-up and Shutdown: 3.15 Distributors Perforated Pipe: 1.15 Drawoffs: See Outlets, Intermediate Entrance Loss: See Drawoffs Exchangers in Fractionation Service: 4.03.1 Feeds: See Inlet Flashing Feeds, see Inlets, Trayed Towers Gasketing of Trays: 1.13 Inlets, Packed Towers Liquid: 2.02.1 Inlets, Trayed Towers Bottom: 1.03 Intermediate: 1.02 Top: 1.01 Installation Packing: 2.01.2 Trays: 1.14 Inspection: Pressure Vessels: 5.01 Trays: 5.02.02; 5.02.04 Packed Towers: 5.02.01; 5.02.03; 5.02.05 Internal Pipework to Packed Tower Distributors: 2.02.2 Leak Tightness: 1.18 Level – Tray Levelness: 1.12 Leveling Trays and Distributors: 5.05 Liquid Flow Through Gravity Distributor Orifices 2.02.4 Page 2 of 3
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