Page 11 - Separation process principles 2

Contents xv

Optimal Reflux Ratio 270
Large Number of Stages 27 1
Use of Murphree Efficiency 272
Multiple Feeds, Side Streams, and Open Steam 273
7.3 Estimation of Stage Efficiency 275
Performance Data 275
Empirical Correlalions 276
Semi-Theoretical Models 278
Scale-up from Laboratory Data 278
7.4 Diameter of Trayed Towers and Reflux Drums 279
Reflux Drums 279
7.5 Rate-Based Method for Packed Columns 280
HETP Method 280
HTU Method 281
7.6 Ponchon-Savarit Graphical Equilibrium-Stage Method for Trayed Towers 283
Summary 284 References 285 Exercises 285

Chapter 8 Liquid-Liquid Extraction with Ternary Systems 295

8.0 Instructional Objectives 295
Industrial Example 296
8.1 Equipment 298
Mixer-Settlers 299
Spray Columns 299
Packed Columns 300
Plate Columns 300
Columns with Mechanically Assisted Agitation 300
8.2 General Design Considerations 305
8.3 Hunter-Nash Graphical Equilibrium-Stage Method 309
Number of Equilibrium Stages 3 10
Minimum and Maximum Solvent-to-Feed Flow-Rate Ratios 313
Use of Right-Triangle Diagrams 3 15
3
Use of an Auxiliary Distribution Curve with a McCabe-Thiele Diagram 7
1
Extract and Raffinate Reflux 3 18
8.4 Maloney-Schubert Graphical Equilibrium-Stage Method 322
8.5 Theory and Scale-Up of Extractor Performance 325
Mixer-Settler Units 325
Multicompartment Columns 332
Axial Dispersion 334
Summary 337 References 338 Exercises 339

Chapter 9 Approximate Methods for Multicomponent,
Multistage Separations 344
9.0 Instructional Objectives 344
9.1 Fenske-Underwood-Gilliland Method 344
Selection of Two Key Components 345
Column Operating Pressure 347