Boilers, Evaporators, and Condensers

BOILERS, EVAPORATORS AND CONDENSERS......Page 1
MAIN COTENTS......Page 2
1.Introduction......Page 3
Contents......Page 4
Introduction......Page 5
2.Basic Design Methods of Heat Exchangers......Page 13
contn......Page 14
2.1Introduction......Page 15
2.2Arrangement of Flow Path in Heat Exchangers......Page 16
2.3Basic Equations in Design......Page 17
2.4Overall Heat Transfer Coefficient......Page 20
2.4.1 Order of Magnitude of Thermal Resistances......Page 24
2.5The LMTD Method for Heat Exchanger Analysis......Page 25
2.5.1 Multipass and Crossflow Heat Exchangers......Page 28
2.6The e-NTU Method for Heat Exchanger Analysis......Page 35
2.7The P-NTUC Method......Page 48
2.8The $-P Method......Page 50
2.9Heat Exchanger Design Calculation......Page 54
2.10Variable Overall Heat Transfer Coefficient......Page 56
2.11.1Tube-Side Pressure Drop......Page 58
2.11.2Noncircular Cross-Sectional Ducts......Page 61
2.11.3Shell-Side Pressure Drop......Page 64
2.11.4Heat Transfer and Pumping-Power Relationship......Page 68
Nomenclature......Page 71
References......Page 73
3.Forced Convection Correlations for Single-Phase Side of Heat Exchangers......Page 75
Contents......Page 76
3.1Introduction......Page 77
3.2Laminar Forced Convection......Page 80
3.2.1Hydrodynamically Developed and Thermally Developing Laminar Flow in Smooth Circular Ducts......Page 81
3.2.2Simultaneously Developing Laminar Flow in Smooth Ducts......Page 82
3.2.3Laminar Flow Through Concentric Smooth Ducts......Page 83
3.3The Effect of Variable Physical Properties......Page 85
3.3.1Laminar Flow of Liquids......Page 86
3.3.2Laminar Flow of Gases......Page 90
3.4.1Turbulent Flow in Circular Ducts with Constant Properties......Page 92
3.6The Effect of Variable Physical Properties in Turbulent Forced Convection......Page 96
3.6.2Turbulent Gas Flow in Ducts......Page 97
3.7Summary......Page 109
Nomenclature......Page 110
References......Page 111
4.Heat Exchanger Fouling......Page 114
Contents......Page 115
4.1Introduction......Page 116
4.2.1Basic Equations......Page 117
4.2.2Effect of Fouling on Heat Transfer......Page 118
4.2.3Effect of Fouling on Pressure Drop......Page 122
4.2.4Cost of Fouling......Page 123
4.3.1Categories of Fouling......Page 124
4.3.2Fundamental Processes of Fouling......Page 126
4.3.3Prediction of Fouling......Page 128
4.4.1Providing a Fouling Allowance......Page 130
4.4.2Design Features to Minimize Fouling......Page 141
4.5Operation of Heat Exchangers Subject to Fouling......Page 142
4.6.1Surface Cleaning Techniques......Page 146
4.6.2Additives......Page 147
Nomenclature......Page 148
References......Page 149
5.Industrial Heat Exchanger Design Practices......Page 151
Contents......Page 152
5.2Heat Exchanger Types, Their Characteristics and Selection......Page 153
5.2.5Matrix and Plate Fin-Tube Exchangers......Page 154
5.3The Strategy of Overall Design Optimization......Page 155
5.3.1Process Specifications......Page 156
5.3.2Preliminary Problem Analysis......Page 157
5.3.3Detailed Thermohydraulic Design......Page 159
5.3.5Architectural Considerations......Page 162
5.4Shell-and-Tube Heat Exchangers: Characteristics of Constructional Components......Page 163
5.4.2Tube Bundle Types......Page 164
5.4.4Baffle Types and Geometry......Page 165
5.4.6Tube Layout......Page 167
5.5Comments on Condenser Design......Page 168
5.6Comments on Reboiler Design......Page 169
5.7.1Process Specifications......Page 170
5.7.3Thermal Profile Analysis: Possible Configurations......Page 171
5.7.5Preliminary Estimation of Unit Size......Page 173
5.7.6Design and Results Evaluation......Page 175
5.8Design by Computer Programs......Page 177
5.9Optimization and Expert Systems Nomenclature......Page 178
Nomenclature......Page 179
Appendix 5.1:Step-by-Step Calculations......Page 180
References......Page 186
7.Once-Through Boilers......Page 287
Contents......Page 288
7.1Introduction (Historical Review)......Page 289
7.2Important Design Criteria in Comparison to Other Systems......Page 295
7.2.1Main Characteristic Features......Page 296
7.2.2Pressure Range......Page 298
7.2.3Operating Modes and Start-Up Period......Page 300
7.2.4Start-Up Equipment and Problems......Page 308
7.2.5Evaporator Tube Design......Page 310
7.2.6Heat Pickup of the Heating Surfaces......Page 316
7.2.7Differences in Heat Absorption and Flow Resistance in Individual Evaporator Tubes......Page 321
7.2.8Furnace Wall Design......Page 326
7.2.9Feed-Water Quality......Page 328
7.2.11Storage Capacity, Load Changes, and Control......Page 329
7.3.1Water Wall Design......Page 333
7.3.2Steam Preheating Equipment......Page 339
7.3.3Water Separation......Page 340
7.4.1Start-Up Systems......Page 344
7.4.2Feed-Water Control......Page 349
7.5.1Lignite Fired 600-MW Once-Through Steam Generator......Page 350
7.5.2Bituminous Coal-Fired 740-MW Once-Through Steam Generator......Page 351
7.5.3Power Boiler for Supercritical 475-MW Unit......Page 353
7.5.4Steam Generator Unit for Steam Soak or Steam Drive in Oil Fields......Page 357
7.6Summary......Page 360
Nomenclature......Page 361
References......Page 363
Appendix 7.1:Example for Calculating Power Generation Costs......Page 366
Appendix 7.2:Optimal Design of a Recirculation Pump Suction Pipe......Page 369
Appendix 7.3:Steam Generator Energy Balance......Page 371
8.Thermohydraulic Design of Fossil-Fuel-Fired Boiler Components......Page 375
Contents......Page 376
8.1.1Working Principle of a Steam Boiler......Page 377
8.2.2Construction and Design Problems of Furnaces......Page 380
8.2.3Construction and Design Problems of Superheaters and Reheaters......Page 395
8.2.4Construction and Design Problems of Economizers......Page 404
8.2.5Construction and Design Problems of Air Heaters......Page 407
8.2.6Construction and Design Problems of Steam Drums......Page 410
8.3.1Boiler Efficiency and Weight of Fuel Fired......Page 411
8.3.2Heat Transfer Calculation of Water-Cooled Furnace......Page 414
8.3.3Heat Transfer Calculation of Convection Heating Surfaces......Page 419
8.3.4Procedure for Heat Transfer Calculation of a Boiler......Page 433
8.4A Numerical Example of the Heat Transfer Calculations of Boiler Components......Page 434
8.5Steam-Water Systems of Boilers and Circulation Calculations......Page 453
8.5.1Steam-Water System of Natural-Circulation Boiler and Design Problems......Page 454
8.5.2Steam-Water System of Controlled-Circulation Boilers and Design Problems......Page 464
8.5.3Steam-Water System of Once-Through Boilers......Page 469
8.6A Numerical Example of Boiler Circulation Calculations......Page 470
Nomenclature......Page 479
References......Page 481
9.Nuclear Steam Generators and Waste Heat Boilers......Page 483
Contents......Page 484
9.2Introduction......Page 485
9.3.1Nuclear Power Plants......Page 486
9.3.2Waste Heat Boilers......Page 500
9.4.2Primary Side (Unfired Boiler) Design......Page 504
9.4.3Water-Side (Evaporator) Design......Page 505
9.4.4An Example: PWR Inverted U-Tube Recirculating Steam Generator......Page 516
9.5.1Causes of Steam Generator Problems......Page 521
9.5.2Worked Solutions......Page 527
Nomenclature......Page 532
References......Page 533
10.Heat Transfer in Condensation......Page 538
Contents......Page 539
10.1Introduction......Page 540
10.2.1Natural Convection......Page 541
10.2.2Forced Convection......Page 543
10.3Film Condensation in Tube Bundles......Page 546
10.3.1Effect of Condensate Inundation......Page 547
10.3.2Effect of Vapor Shear......Page 549
10.3.3Combined Effects of Inundation and Vapor Shear......Page 550
10.4.1Flow Patterns......Page 554
10.4.2Condensation in Horizontal Tubes......Page 555
10.4.3Condensation in Vertical Tubes......Page 559
10.5.1Shell-Side Pressure Drop......Page 561
10.5.2Pressure Drop Inside Tubes......Page 562
10.6.1Shell-Side Film Condensation Using Integral-Fin Tubes......Page 565
10.6.2Dropwise Condensation......Page 570
10.7Condensation of Vapor Mixtures......Page 571
10.7.1Equilibrium Methods......Page 574
10.7.2Nonequilibrium Methods......Page 576
Nomenclature......Page 577
References......Page 580
11.Steam Power Plant and Process Condensers......Page 586
Contents......Page 587
11.1Introduction......Page 588
11.2.1Horizontal Shell-Side Condensers......Page 590
11.2.3Tube-Side Condensers......Page 599
11.2.4Subcooling in Shell-and-Tube Condensers......Page 600
11.3.1Steam Turbine Exhaust Condensers......Page 602
11.3.2Feed-Water Heaters......Page 605
11.5Spiral Exchangers......Page 608
11.6Plate-Fin Heat Exchangers......Page 609
11.7Air-Cooled Heat Exchangers......Page 611
11.8Direct-Contact Condensers......Page 612
11.9.1Introduction and Definition of Terms......Page 614
11.9.2Co-current and Countercurrent Condensers......Page 617
11.9.3Shell-Side, E-Type Condenser with Two Tube-Side Passes......Page 620
11.9.4Shell-Side, E-Type Condenser with Four or More Tube Passes......Page 623
11.9.5Crossflow Condensers......Page 624
11.9.6Nonequilibrium Calculation Methods......Page 625
11.9.7Multidimensional Shell-Side Flows......Page 628
11.10.1Spray Condensers......Page 629
11.11Reasons for Failure of Condenser Operation......Page 633
11.12.1Process Condenser......Page 634
11.12.2Power Condenser......Page 640
Acknowledgment......Page 646
Nomenclature......Page 647
References......Page 648
12.Evaporators and Condensers for Refrigeration and Air-Conditioning Systems......Page 651
12.1.2Typical Evaporator Behavior......Page 652
12.1.1Background......Page 653
12.1.3Typical Condenser Behavior......Page 656
12.1.4Types of Heat Exchangers in Refrigeration and Air-Conditioning Applications......Page 657
12.2.1General Equations......Page 659
12.2.2Lumped Heat Exchanger Analysis Approach......Page 662
12.2.3Local Heat Transfer Integration Approach......Page 664
12.3.1Description and Special Considerations......Page 665
12.3.2In-Tube Refrigerant Evaporation Heat Transfer......Page 668
12.3.3In-Tube Heat Transfer Augmentation......Page 675
12.3.4Air-Side Heat Transfer......Page 681
12.3.5Wet-Coil Heat Transfer......Page 689
12.3.6Frosted-Coil Heat Transfer......Page 690
12.3.7Fin Bonding and Thermal Contact Resistance......Page 691
12.4.2Similarities between Condenser and Evaporator Coils......Page 697
12.4.3In-Tube Refrigerant Condensation Heat Transfer......Page 698
12.4.4In-Tube Heat Transfer Augmentation......Page 702
12.5.1Description and Special Considerations......Page 705
12.5.2Shell-Side Refrigerant Heat Transfer......Page 706
12.5.3Shell-Side Heat Transfer Augmentation......Page 712
12.6.1Description and Special Considerations......Page 716
12.6.2In-Tube and Shell-Side Heat Transfer......Page 717
12.7.1Description and Special Considerations......Page 718
12.7.2Shell-Side Refrigerant Condensation Heat Transfer......Page 719
12.7.3Shell-Side Heat Transfer Augmentation......Page 722
12.8Heat Exchanger Design with Alternative Refrigerants......Page 723
Nomenclature......Page 728
References......Page 730
13.Evaporators and Reboilers in the Process and Chemical Industries......Page 735
Contents......Page 736
13.1Introduction......Page 738
13.2Relevance of Upflow and Downflow in Vertical Units......Page 740
13.3Evaporator Types......Page 742
13.3.1Horizontal Shell-Side Evaporator......Page 743
13.3.2Horizontal Falling-Film Evaporator......Page 745
13.3.3Horizontal Tube-Side Evaporator......Page 746
13.3.4Short-Tube Vertical Evaporator......Page 747
13.3.5Long-Tube Vertical Evaporator......Page 750
13.3.7Vertical Falling-Film Evaporator......Page 751
13.3.8Agitated Thin Film Evaporator......Page 753
13.3.9Plate-Type Evaporator......Page 755
13.3.10Submerged-Combustion Evaporator......Page 757
13.4.2Kettle Reboiler......Page 759
13.4.3Vertical Thermosyphon Reboiler......Page 761
13.4.4Horizontal Thermosyphon Reboiler......Page 763
13.5.2Multiple-Effect Evaporators......Page 765
13.5.3Vapor Recompression in Evaporation......Page 768
13.5.4Multistage Flash Evaporator......Page 769
13.6.1Initial Sizing of the Unit......Page 772
13.6.2Two-Phase Vapor-Liquid Pressure Drop......Page 774
13.6.3Calculation of Natural-Circulation Units......Page 778
13.6.4Heat Transfer Rates......Page 781
13.6.5Heat Transfer on the Heating Side......Page 782
13.6.7Boiling inside Tubes......Page 783
13.6.8Boiling outside Tubes......Page 787
13.6.9Falling-Film Evaporation......Page 788
13.6.11Mixture Effects......Page 789
13.6.12Enhanced Surfaces......Page 790
13.7.1Introduction......Page 791
13.7.4Fouling......Page 792
13.7.5Flow Instability......Page 794
13.8Design Example......Page 795
13.8.1Further Refinements in the Design......Page 798
Nomenclature......Page 799
References......Page 800
Appendix A.Thermophysical Properties......Page 803
Contents......Page 804
Nomenclature......Page 806
List of Sources of Tables......Page 807
References......Page 808
Table A1.Thermophysical Properties of 113 Fluids at 1 bar, 300 K......Page 809
Table A2.Thermophysical Properties of Liquid and Saturated-Vapor Air......Page 814
Table A3.Thermophysical Properties of Gaseous Air at Atmospheric Pressure......Page 816
Table A4.Thermophysical Properties of Saturated Ammonia (R717)......Page 818
Table A5.Thermophysical Properties of Ammonia (R717) at 1-bar Pressure......Page 819
Table A6.Thermophysical Properties of Saturated Normal Butane (R600)......Page 820
Table A7.Thermophysical Properties of Normal Butane (R600) at Atmospheric Pressure......Page 821
Table A8.Thermophysical Properties of Solid, Saturated-Liquid and Saturated-Vapor Carbon Dioxide......Page 822
Table A9.Thermophysical Properties of Gaseous Carbon Dioxide at 1-bar Pressure......Page 823
Table A10.Thermophysical Properties of Saturated Ethane (R170)......Page 824
Table A11.Thermophysical Properties of Ethane at Atmospheric Pressure......Page 825
Table A12.Thermophysical Properties of Saturated Ethylene (R1150)......Page 826
Table A14.Thermophysical Properties of n-Hydrogen (R702) at Atmospheric Pressure......Page 827
Table A16.Thermophysical Properties of Methane (R50) at Atmospheric Pressure......Page 828
Table A17.Thermophysical Properties of Nitrogen (R728) at Atmospheric Pressure......Page 829
Table A18.Thermophysical Properties of Oxygen (R732) at Atmospheric Pressure......Page 830
Table A19.Thermophysical Properties of Saturated Normal Propane (R290)......Page 831
Table A20.Thermophysical Properties of Propane (R290) at Atmospheric Pressure......Page 832
Table A21.Thermophysical Properties of Saturated Refrigerant 12......Page 833
Table A22.Thermophysical Properties of Refrigerant 12 at 1-bar Pressure......Page 835
Table A23.Thermophysical Properties of Saturated Refrigerant 22......Page 836
Table A24.Thermophysical Properties of Refrigerant 22 at Atmospheric Pressure......Page 838
Table A25.Thermophysical Properties of Saturated R134a......Page 839
Table A26.Properties of Refrigerant 134a at Atmospheric Pressure......Page 840
Table A27.Thermophysical Properties of Saturated Ice-Water-Steam......Page 841
Table A28.Thermophysical Properties of Steam at 1-bar Pressure......Page 846
Table A29.Thermophysical Properties of Water-Steam at High Pressures......Page 847
Table A31.Isothermal Compressibility Coefficient......Page 849
Table A33.Conversion Factors......Page 850