Unit Operations of Chemical Engineering

front.pdf......Page 1 Table of Contents......Page 0 Table of Contents......Page 2 What Are "Unit Operations"?......Page 5 Shell-and-Tube Hxer......Page 7 Log-Mean Driving Force......Page 9 Resistances in Series......Page 14 Correlations to Estimate h’s......Page 17 hi for Turbulent Flow In Long Pipes......Page 19 Baffles......Page 20 ho for Shell-and-Tube Exchanger......Page 21 Appendix: Derivation for Sb and Sc......Page 23 Multipass Construction......Page 25 "True" Mean Temperature Difference......Page 26 Equipment for Evaporation......Page 31 Long-Tube Vertical Evaporator......Page 32 Example: Simple Evaporator Problem......Page 33 Steam Economy......Page 37 Overview of Evaporator Design......Page 38 Boiling-Point Elevation......Page 39 Heat of Dilution......Page 41 Multiple Effects......Page 42 Performance......Page 45 Vapor Recompression......Page 46 Two Components......Page 50 Ideal Binary Mixtures......Page 52 xy and Txy Diagrams......Page 55 Nonideal Behavior......Page 56 Approximate Solution......Page 57 Inverse Lever-Arm Rule on Txy Diagram......Page 59 Rigorous Solution......Page 60 Batch (Differential) Distillation......Page 63 Multistage Operations......Page 68 Counter-Current Cascade......Page 69 Equipment for Tray Towers......Page 71 Analysis of a C-C Cascade......Page 74 Constant Molal Overflow......Page 75 A Rectifying Cascade......Page 77 A Stripping Cascade......Page 80 Steam Distillation......Page 83 McCabe-Thiele Method......Page 84 Location of Feed Plate......Page 86 Convergence of Operating Line and Equilibrium Curve......Page 87 Choosing the Reflux Ratio......Page 92 1) Existence of Rmin......Page 93 2) Total Reflux: R?? gives Minimum Stages......Page 94 Calculating Flowrates and Condenser/Reboiler Heat Duties......Page 96 Role of q-Line......Page 98 Plate Efficiency......Page 99 Determining Number of Real Stages......Page 102 Multi-Component Distillation......Page 103 Product Distribution for a Sharp Split......Page 104 Minimum Number of Trays......Page 106 Method 1) Psuedo-Binary Method......Page 111 Method 2) Underwood's Method......Page 113 Method 3) Rigorous Solution of MESH Equations......Page 117 Computer Simulation of Distillation......Page 120 Some Preliminary Steps......Page 121 Loading a File (Problem)......Page 123 Plotting the McCabe-Thiele Diagram......Page 134 Printing the Graphs......Page 136 Testing the McCabe-Thiele Method......Page 137 Degrees of Freedom......Page 141 Equipment for Absorption/Stripping......Page 143 A Typical Absorber Design Problem......Page 145 Solution Overview:......Page 146 Equilibrium Curve......Page 147 Operating Line......Page 148 Approx. #1: Only One Transferable Component......Page 149 Interfacial Mass Transfer: Review......Page 152 Definitions of Transfer Coefficients......Page 154 Determining the Interfacial Concentrations: (xi,yi)......Page 155 Equimolar Counter-Diffusion vs. Diffusion through Stagnant Fluid......Page 158 Height of a Packed Tower......Page 160 Transfer Unit......Page 164 Evaluation of NTU's......Page 166 Analogy with Double-Pipe HXer......Page 168 Relationships among HOx, HOy, Hx and Hy......Page 169 Pressure Drop in Pack Beds......Page 171 Tower Diameter......Page 173 Gases......Page 177 Equipment......Page 178 Porous Membranes......Page 181 Nonporous Polymer Membranes......Page 182 Example: Production of Enriched Air......Page 183 Stage Cut......Page 186 Liquid-Liquid Extraction......Page 188 Equipment......Page 189 Triangle Diagrams......Page 190 Nomenclature......Page 191 Flash Mixing of Two Liquids......Page 192 Single-Stage Extractor......Page 194 Multi-Stage Extractor......Page 195 Difference-Point Method......Page 197