Reverse Osmosis: Design, Processes, and Applications for Engineers

Reverse Osmosis......Page 5
Contents......Page 9
Preface......Page 19
PART 1 FUNDAMENTALS......Page 23
1.1.1 Uses of Reverse Osmosis......Page 25
1.1.2 History of Reverse Osmosis Development......Page 27
1.1.3 Recent Advances in RO Membrane Technology......Page 31
References......Page 34
2.1 Osmosis......Page 37
2.2 Reverse Osmosis......Page 38
2.3 Dead-End Filtration......Page 39
2.4 Cross-Flow Filtration......Page 40
3.2 Recovery......Page 43
3.3 Rejection......Page 45
3.4 Flux......Page 48
3.5 Concentration Polarization......Page 49
3.6 Beta......Page 51
3.7 Fouling......Page 52
3.8 Scaling......Page 55
3.9 Silt Density Index......Page 57
3.10 Langelier Saturation Index......Page 60
References......Page 61
4.1 Transport Models......Page 63
4.1.1 Solution-Diffusion Model non-porous model)......Page 64
4.1.2 Solution – Diffusion Imperfection Model (porous model)......Page 66
4.1.4 Preferential Sorption – Capillary Flow Model (porous model)......Page 67
4.2 Membrane Materials......Page 68
4.2.3 Improvements to Polyamide, Composite Membranes......Page 78
4.3 Membrane Modules......Page 80
4.2.1 Cellulose Acetate Membranes–Asymmetric membranes......Page 69
4.2.2.1 Linear Aromatic Polyamide Membranes......Page 73
4.2.2.2 Composite Polyamide Membranes......Page 74
4.3.1 Plate and Frame Modules......Page 81
4.3.2 Tubular Modules......Page 82
4.3.3 Spiral Wound Modules......Page 83
4.3.4 Hollow Fine Fiber Membrane Modules......Page 94
4.3.5 Other Module Configurations......Page 96
4.4.1 Seawater Membranes......Page 98
4.4.2 Brackish Water Membranes......Page 100
4.4.2.3 Low-Fouling Membranes......Page 101
4.4.2.4 Low-Differential-Pressure Membrane Modules......Page 102
4.4.2.6 Other Membrane/Module Types......Page 103
References......Page 105
5.1 Arrays......Page 107
5.2 Recycle......Page 111
5.3 Double Pass......Page 112
5.4 Multiple Trains......Page 115
6 Reverse Osmosis Skids......Page 117
6.1 Cartridge Filters......Page 119
6.2 Reverse Osmosis Feed Pumps......Page 122
6.3 Pressure Vessels......Page 128
6.5 Instrumentation......Page 136
6.6 Controls......Page 138
6.7 Data Acquisition and Management......Page 140
6.9 Auxiliary Equipment......Page 142
6.10.2 Interstage Performance Monitoring Instrumentation......Page 143
References......Page 144
PART 2 PRETREATMENT......Page 145
7.1 Suspended Solids......Page 147
7.2 Microbes......Page 149
7.3 Organics......Page 150
7.4 Color......Page 151
7.5 Metals......Page 152
7.6 Hydrogen Sulfide......Page 153
7.7 Silica......Page 154
7.8 Calcium Carbonate......Page 156
7.10 Chlorine......Page 158
7.11 Calcium......Page 159
References......Page 161
8 Techniques and Technologies......Page 163
8.1.1 Clarifiers......Page 164
8.1.1.1 Solids-Contact Clarifiers......Page 166
8.1.1.2 Inclined-Plate Clarifiers......Page 167
8.1.1.3 Sedimentation Clarifiers......Page 170
8.1.1.4 Chemical Treatment for Clarifiers......Page 171
8.1.2 Multimedia Pressure Filters......Page 173
8.1.3 High-Efficiency Filters......Page 175
8.1.4 Carbon Filters......Page 179
8.1.5 Iron Filters......Page 182
8.1.5.1 Manganese Greensand Filters......Page 183
8.1.5.2 BIRM® Filters......Page 184
8.1.5.4 Other Iron Removal Media......Page 185
8.1.6 Sodium Softeners......Page 186
8.1.7 Spent Resin Filters......Page 189
8.1.8 Ultraviolet Irradiation......Page 190
8.2 Chemical Pretreatment......Page 192
8.2.1.1 Chlorine......Page 193
8.2.1.2 Ozone......Page 198
8.2.2 Antiscalants......Page 199
8.2.3 Sodium Metabisulfite......Page 202
8.2.4.2 DBNPA......Page 204
8.3 Combination Mechanical Plus Chemical Pretreatment—Lime Softening......Page 205
8.3.1 Cold Lime Softening......Page 206
8.3.3 Hot Process Softening......Page 207
8.4 Sequencing of Pretreatment Technologies......Page 209
References......Page 211
PART 3 SYSTEM DESIGN......Page 213
9.1.1 Feed Water Source......Page 215
9.1.2 Total Dissolved Solids......Page 218
9.1.3 Calcium and Natural Organic Matter......Page 219
9.2 Temperature......Page 220
9.3 Pressure......Page 222
9.4 Feed Water Flow......Page 223
9.6 Beta......Page 224
9.7 Recovery......Page 227
9.8 pH......Page 229
References......Page 231
10 RO Design and Design Software......Page 233
10.1 ROSA Version 6.1......Page 236
10.2 TorayDS Version 1.1.44......Page 243
10.3 Hydranautics IMS Design Version 2008......Page 246
10.4 Koch Membranes ROPRO Version 7.0......Page 252
Reference......Page 256
PART 4 OPERATIONS......Page 257
11.2 Data Collection......Page 259
11.3.1 Data Normalization......Page 261
11.3.1.1 Normalized Product Flow......Page 262
11.3.1.2 Normalized Salt Passage......Page 265
11.3.1.3 Normalized Pressure Drop......Page 267
11.3.2 Normalization Software......Page 269
11.4 Preventive Maintenance......Page 272
References......Page 275
12.1.1.1 Membrane Fouling......Page 277
12.1.2.1 Membrane Degradation......Page 278
12.1.2.2 Hardware Issues......Page 279
12.2.1.1 Membrane Scaling......Page 280
12.3 Pressure Drop......Page 281
12.3.2 Increase in Pressure Drop......Page 282
References......Page 283
13.1.1 Off-Line Flush......Page 285
13.1.2 Return to Service Flush......Page 286
13.1.3 Stand-by Flush......Page 287
13.2.1 When to Clean......Page 288
13.2.2 How to Clean......Page 289
13.2.3 Cleaning Chemicals......Page 292
13.2.3.1 High-pH cleaners......Page 293
13.2.3.2 Neutral-pH Cleaners......Page 294
13.2.3.3 Low-pH Cleaners......Page 295
13.2.4 Cleaning Equipment......Page 296
13.2.4.1 Cleaning Tank......Page 297
13.3.1 Short-Term Lay-Up......Page 299
References......Page 300
PART 5 TROUBLESHOOTING......Page 303
14 Troubleshooting......Page 305
14.1 Mechanical Evaluation......Page 306
14.3.1 System Design......Page 307
14.3.2 Performance Projections......Page 308
14.4 Data Assessment......Page 309
14.5 Water Sampling......Page 312
14.7 Profiling and Probing......Page 313
14.8 Membrane Autopsy......Page 316
14.8.1 Visual Inspection......Page 317
14.8.3 Methylene Blue Test......Page 323
14.8.5 Spectroscopy......Page 324
14.8.6 Other Tests......Page 325
References......Page 326
PART 6 SYSTEM ENGINEERING......Page 327
15.1.1 Sequencing of the Sodium Softeners and RO......Page 329
15.1.2 Sodium Softening and Antiscalants......Page 331
Case 1: High Hardness Well Water......Page 332
Antiscalant......Page 333
Summary......Page 334
Antiscalant......Page 335
Antiscalant......Page 336
15.2 Reverse Osmosis Sizing and Capacity......Page 338
15.3.1 Off-Site Membrane Cleaning......Page 339
15.3.2 On-Site Membrane Cleaning......Page 340
15.4 Reverse Osmosis Reject Disposal Options......Page 341
15.4.2 Discharge to Cooling Tower......Page 342
15.4.3 Zero Liquid Discharge......Page 343
References......Page 345
16.1 Microfiltration and Ultrafiltration......Page 347
16.1.1 Microfiltration......Page 360
16.1.2 Ultrafiltration......Page 361
16.2 Nanofiltration......Page 364
16.3 Continuous Electrodeionization......Page 366
16.4 HERO Process......Page 380
References......Page 382
PART 7 FREQUENTLY ASKED QUESTIONS......Page 385
17.1.2 What is the Difference Between Nanofiltration and Reverse Osmosis?......Page 387
17.1.5 Why Does the pH Drop from the RO Feed to the RO Permeate?......Page 388
17.2.3 What Temperature Cleaning Solution Should Be Used to Clean Membranes?......Page 389
17.2.6 What Should Be Done if Cleaning Does Not Return Performance to Baseline?......Page 390
17.2.10 Why is Chlorine Both Added and then Removed Prior to the RO?......Page 391
17.2.12 Why Does the RO Trip Off on Low Suction Pressure?......Page 392
17.2.14 What Limits Recovery by an RO?......Page 393
17.2.16 Do RO Membranes Need to Be Preserved When Taken Off Line?......Page 394
17.2.17 Is there a Shelf Life for Reverse Osmosis Membranes?......Page 396
17.2.19 What is the Impact on the RO If the Pretreatment System Fails, for Example, If the Softener Leaks Hardness?......Page 397
17.2.20 Can Different Types of Membranes Be Used in an RO Unit?......Page 398
17.3.2 What is a Variable Frequency Drive Used for?......Page 399
17.3.3 What is the Difference Between Pleated, String-Wound, and Melt-Blown Cartridge Filters?......Page 400
References......Page 401
Unit Equivalent and Conversions......Page 403
Index......Page 405