Page 22 - Fundamentals of Water Treatment Unit Processes : Physical, Chemical, and Biological

Contents xxi

15.2.2 Kinetics....................................................................................................................................... 471
15.2.2.1 Graphical Depiction.................................................................................................... 471
15.2.2.2 Rate of Uptake: Theoretical........................................................................................ 473
15.2.2.3 Empirical Rate Equation............................................................................................. 473
15.2.3 Reactor Theory for Packed Beds ............................................................................................... 473
15.2.3.1 Mathematics................................................................................................................ 473
15.2.3.2 Advection Kinetics...................................................................................................... 474
15.2.3.3 Simulation Modeling .................................................................................................. 476
15.2.3.4 Characteristics of Output Curves................................................................................ 477
15.2.4 Rational Design .......................................................................................................................... 479
15.2.4.1 Quick-and-Dirty Mass Balance................................................................................... 480
15.2.4.2 Empirical Data for L wf and v wf ................................................................................... 481
15.2.4.3 Theoretical Results for L wf and v wf ............................................................................ 481
15.2.5 Problems..................................................................................................................................... 481
15.2.5.1 Competition between Adsorbents............................................................................... 481
15.2.5.2 Chromatographic Effect.............................................................................................. 482
15.2.5.3 Bacterial Colonization................................................................................................. 482
15.3 Laboratory and Pilot Plant Studies.......................................................................................................... 483
15.3.1 Questions for a Laboratory=Pilot Plant Study............................................................................ 483
15.3.1.1 Isotherm Determination .............................................................................................. 483
15.3.1.2 Determine v(wave front)............................................................................................. 483
15.3.1.3 L(wave front) .............................................................................................................. 484
15.3.1.4 Breakthrough Curve.................................................................................................... 484
15.3.1.5 Rate of Headloss Increase........................................................................................... 484
15.3.1.6 Backwash Velocity ..................................................................................................... 484
15.3.1.7 Assess Competitive Effects of Different Adsorbates ................................................. 484
15.3.1.8 Discover Effects of Unanticipated Problems.............................................................. 484
15.3.1.9 Fabrication .................................................................................................................. 484
15.3.2 Demonstration-Scale Plants........................................................................................................ 484
15.3.2.1 Pomona ....................................................................................................................... 484
15.3.2.2 Denver Reuse Plant..................................................................................................... 485
15.4 Design...................................................................................................................................................... 486
15.4.1 Design Variables ........................................................................................................................ 486
15.4.1.1 Independent Process Variables ................................................................................... 486
15.4.1.2 Guidelines and Criteria ............................................................................................... 488
15.4.2 Design Protocol .......................................................................................................................... 489
15.4.2.1 Spreadsheet Layout..................................................................................................... 489
15.4.2.2 Spreadsheet Scenarios................................................................................................. 490
15.4.3 Design Examples........................................................................................................................ 490
15.4.3.1 Examples of Sites ....................................................................................................... 490
15.4.3.2 GAC for Taste-and-Odor Control............................................................................... 490
15.4.3.3 Chemicals in Drinking Water Sources ....................................................................... 490
15.4.3.4 Pump and Treat........................................................................................................... 492
15.4.3.5 Tertiary Treatment ...................................................................................................... 494
15.5 Operation and Costs ................................................................................................................................ 496
15.5.1 Operation Characteristics............................................................................................................ 496
15.5.2 Costs ........................................................................................................................................... 496
15.5.2.1 South Lake Tahoe....................................................................................................... 496
15.5.2.2 Virgin GAC ................................................................................................................ 496
15.5.2.3 Regeneration ............................................................................................................... 496
Problems............................................................................................................................................................. 497
Acknowledgments .............................................................................................................................................. 499
Appendix 15.A: Freundlich Isotherm Coefficients ......................................................................................... 499
Glossary.............................................................................................................................................................. 499
References .......................................................................................................................................................... 507
Further Readings ................................................................................................................................................ 510