RULES OF THUMB FOR CHEMICAL ENGINEERS
A manual of quick, accurate solutions to everyday
process engineering problems
Fourth Edition
Carl R. Branan, Editor
AMSTERDAM • BOSTON • HEIDELBERG • LONDON
NEW YORK • OXFORD • PARIS • SAN DIEGO
SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO
Gulf Professional Publishing is an imprint of Elsevier
G P
Contents
SECTION ONE
3: Fractionators, 59
Equipment Design
Introduction
Relative volatility
Minimum reflux
Minimum stages
Actual reflux and actual theoretical stages..
Reflux to feed ratio
Actual trays
Graphical methods
Tray efficiency
Diameter of bubble cap trays
Diameter of sieve/valve trays (F factor)
Diameter of sieve/valve trays (Smith)
Diameter of sieve/valve trays (Lieberman)
Diameter of ballast trays
Diameter of fractionators, general
Control schemes
Optimization techniques...
Reboilers.
Packed columns
1: Fluid Flow, 2
Velocity head
Full plant piping
Partially full horizontal pipes
Equivalent length
;
Recommended velocities
Two-phase
flow
Compressible flow—short (plant) lines
Compressible flow—long pipelines
Sonic velocity
Metering
Control valves
Safety relief valves
3
4
5
6
7
9
12
18
21
21
22
25
2: Heat Exchangers, 29
.
TEMA
Selection guides. ,
Pressure drop shell and tube
Temperature difference
Shell diameter
Shellside velocity maximum
Nozzle velocity maximum
Heat transfer coefficients
Fouling resistances
Metal resistances
Vacuum condensers
Air-cooled heat exchangers: forced vs
induced draft
Air-cooled heat exchangers: pressure drop
air side.....
Air-cooled heat exchangers: rough rating
Air-cooled heat exchangers: temperature
control
Miscellaneous rules of thumb
60
60
61
62
62
63
64
64
67
71
72
73
75
75
77
77
81
84
88
4: Absorbers, 109
30
34
37
39
40
40
41
41
48
50
52
Introduction
Hydrocarbon absorber design
Hydrocarbon absorbers, optimization
Inorganic type
110
110
112
113
5: Pumps, 116
Affinity laws
Horsepower
Efficiency
Minimum
flow
General suction system
Suction system NPSH available
Suction system NPSH for studies.....
Suction system NPSH with dissolved gas
Larger impeller
Construction materials
52
53
54
56
58
VII
117
117
117
117
118
119
120
121
121
121
6: Compressors, 124
Ranges of application
Generalized Z
Generalized K
Horsepower calculation
Efficiency
Temperature rise
Surge controls
125
125
126
127
131
133
133
Deaerator venting
Water alkalinity
Blowdown control
Impurities in water
Conductivity versus dissolved solids
Silica in steam
Caustic embrittlement
Waste heat
159
KJQ
iggj
16Q ;
I62J
1631
163
165J
10: Cooling lowers, 168
7: Drivers, 134
Motors: efficiency
Motors: starter sizes
Motors: service factor
Motors: useful equations
Motors: relative costs
Motors: overloading
Steam turbines: steam rate
Steam turbines: efficiency
Gas turbines: fuel rates
Gas engines: fuel rates
Gas expanders: available energy
135
136
136
137
137
138
138
138
139
141
141
8: Separators/Accumulators, 142
Liquid residence time
Vapor residence time
Vapor/liquid calculation method
Estimating equilibria
Liquid/liquid calculation method
Pressure drop
Vessel thickness
Gas scrubbers
Reflux drums
General vessel design tips
143
144
145
148
150
150
151
151
151
152
9: Boilers, 153
Power plants
Controls
Thermal efficiency
Stack gas enthalpy
Stack gas quantity
Steam drum stability
154
154
155
156
157
158
System balances
Temperature data
Performance
Performance estimate: a case history
Transfer units
169
169
171
173
173
SECTION T W O
Process Design
175
11: Refrigeration, 176
Types of systems
Estimating horsepower per ton
Horsepower and condenser duty for specific
refrigerants
Refrigerant replacements
Ethylene/propylene cascaded system
Steam jet type utilities requirements
Ammonia absorption type utilities
requirements
177
177
178
196
197
197
200
12: Gasification (by Chris Higman), 201
What Is Gasification?
Gasification Theory
Feedstocks for Gasification
Features of Gasification Systems
Commercial Gasification Systems
Trace Components in Gasifier Syngas
202
202
204
205
207
210
13: Gas Treating (updated by Chris Higman), 213
Introduction
Gas Treating Processes
214
214
Chemical Solvent Processes
Physical Solvent Processes
Physical/Chemical Solvent Processes
Biological Processes
Solid Bed Scavengers
Membranes
215
218
218
219
219
220
Capital investments
Operating costs
Economics
Financing
258
.265
268
272
18: Reliability, 274
14: Vacuum Systems, 221
Vacuum jets
Typical jet systems
Steam supply
Measuring air leakage
Time to evacuate
Design recommendations
Ejector specification sheet
222
223
224
225
225
226
227
15: Pneumatic Conveying, 229
Types of systems
Differential pressures
Equipment sizing
230
231
231
19: Metallurgy, 277
Embrittlement
Stress-corrosion cracking
Hydrogen attack
Pitting corrosion
Creep and creep-rupture life
Metal dusting
Naphthenic acid corrosion
Fuel ash corrosion
Thermal fatigue
Abrasive wear
Pipeline toughness
Common corrosion mistakes
278
284
285
287
288
290
292
293
295
297
298
299
16: Blending, 233
Single-stage mixers
Multistage mixers
Gas/liquid contacting
Liquid/liquid mixing
Liquid/solid mixing
Mixer applications
Shrouded blending nozzle
Vapor formation rate for tank
SECTION
filling
234
234
235
235
235
236
237
237
239
17: Process Evaluation, 240
Introduction
Study definition
Process definition
Battery limits specifications
Offsite specifications
Estimating LEL and
flash
Tank blanketing
Equipment purging
Static charge from
fluid
flow
Mixture
flammability
Relief manifolds
'.
Natural ventilation
301
301
303
.....304
307
310
316
21: Controls, 317
THREE
Plant Design
20: Safety, 300
....241
...241
243
250
254
Introduction
Extra capacity for process control
Controller limitations
False economy
Definitions of control modes
Control mode comparisons
Control mode vs application
Pneumatic vs electronic controls
Process chromatographs
318
318
.319
320
320
320
320
321
322
Contents
SECTION
FOUR
Operations
323
22: Troubleshooting, 324
Introduction
Fractionation: initial checklists
Fractionation: troubleshooting checklist
Fractionation: operating problems
Fractionation: mechanical problems
Fractionation: getting ready for
troubleshooting
Fractionation: "normal" parameters
Fluid
flow
Refrigeration
Firetube heaters
Safety relief valves
Gas treating
Compressors
Measurement
325
325
327
329
335
341
341
342
346
347
348
349
353
355
23: Startup, 356
Introduction
Settings for controls
Probable causes of trouble in controls
Checklists
Process modeling using linear
programming
.385
27: Properties, 390
Introduction
Approximate physical properties
Liquid Viscosity
Relative humidity
Surface tension
Gas diffusion coefficients
Water and hydrocarbons
Natural gas hydrate temperature
Inorganic gases in petroleum
Foam density
Equivalent diameter
Autoignition temperature
Gibbs free energy of formation
New refrigerants...
...391
391
392
396
397
397
399
403
405
407
....408
410
415
425
28: Approximate Conversion Factors, 426
357
357
358
360
24: Energy Conservation, 364
Target excess oxygen
Stack heat loss
Stack gas dew point
Equivalent fuel values
Heat recovery systems
Process efficiency
Steam traps
Gas expanders
Fractionation
Insulating materials
26: Process Modeling Using Linear Programming,
384
365
366
366
368
369
370
371
373
374
374
Approximate conversion factors
Appendixes
427
429
Appendix 1: Shortcut Equipment Design
Methods—Overview, 430
Appendix 2: Geographic Information Systems, 432
Appendix 3: Archimedes' Method Goes Modern,
434
Appendix 4: Process Safety Management, 435
Appendix 5: Do-It-Yourself Shortcut Methods, 437
25: Shortcut Methods for Decisions, 375
Introduction
Study problem
Conclusions
Appendix 6: Overview for Engineering Students, 444
376
376
383
Appendix 7: Guidelines for Equipment Decisions,
447
Contents
Appendix 8: Process Specification Sheets, 460
Vessel data sheet
Shell and tube exchanger data sheet
Double pipe (G-fin) exchanger data sheet
Air-cooled (fin-fan) exchanger data sheet
Direct fired heater data sheet
Centrifugal pump (horizontal or vertical)
data sheet
461
462
463
464
465
466
Pump (vertical turbine—can or propellor)
data sheet
Tank data sheet
Cooling tower data sheet
Index, 473
xi
467
468
469