Page 926 - Fundamentals of Water Treatment Unit Processes : Physical, Chemical, and Biological

Index 881

fine screens, 83–86 ideal basin Slow sand technology, 395
microscreens, 86–93 camp’s conditions, 99 Sludge, 717
SCWO, see Supercritical water oxidation (SCWO) detention time, 101 Sludge age, 717
Secondary treatment, 717 flow, 131 Sludge blanket, see Schmutzdecke
Sedimentation overflow velocity, 99–101 Sludge blanket clarifier, see Solid contact units
dead zone, 130 partial removals, 101–102 Sludge-density index, 717
definition, 131 suspension test, 128 Sludge-volume index (SVI), 132, 717
discrete particle, 130, 132 overflow launders, 131 Sludge wasting, 717
dispersion, 130 overflow rate (OR), 131 Smoluchowski’s collision equations, 294–296
dynamic viscosity, 131 overflow velocity, 131 Sodium hypochlorite, 621, 630, 639
final clarifier, 131 particles removal, 128 Softening
floc, 131 primary clarifier, 131 applications, 661–662
flocculent suspensions real basins, 118–121 definition, 536
percent removal determination, 106–107 rectangular sedimentation, 128 ion exchange, 512
settling test, 106, 129 rim-flow clarifier, 131 reactions, 668–669
flow net and rate, 131 short circuiting, 132 Solid alum
fractal, 131 sizing, 128 chemical feed, 833
hindered and compression settlement surface overflow velocity, 132 cost, 836
final settling, limiting flux density, suspensions removal, 129 dissolution
108–112 Sewage oxidation, 721 dispersion, 837
settling velocity, solids concentration, 108 Shallow=Traye air stripping unit, 584 mixing criteria, 837
kinematic viscosity, 131 Shulze-Hardy rule, 226, 234 granular, mass flow, 833–835
particle settling Sieve analysis, 787 properties, dry alum, 835
principles, 95 Silt density index, 568 storage, 836
Stokes’ law, 95–97 Silver, disinfectant, 612, 639 Solid contact units
suspensions, 97–99 Similitude, mixing design practice, equipment, operation, 321, 325
plate settlers design, 281–282 principles, 320–321
particle path, 122–123 dimensionless numbers, 255–256 super-pulsator, 321
sizes of units, 124 experimental plots, 256 Solids contact clarifier, 132
sludge removal, 123 impeller–basin mixing, 256 Solubility
surface overflow rates, 124 Rushton’s role, 255 equilibrium, 663
systems, 123–124 scale-up dilemma, 258–260 ionic compounds
theory, 124–127 scale-up, fluid, 256–258 products, 664–665
settling basins Sink, 57, 76 rules, 667
design practice, 114–120 SI system, see International system, law and application, 663–664
hydraulics, 113–114 units pC–pH diagrams, 665–666
ideal basin, 99–102 Skimmer, 187 pe–pH diagrams, 666–667
real basin, 18–21 Slow sand Solute rejection, 568
Shield’s equation, 131 filters, 53–54 Sorption, 457, 506
suspension characterization filtration, 390 Specific ultraviolet absorbance (SUVA), 234
discrete particle and removal Slow sand filter Sphaerotilus, 717
analysis, 103 cities using, in 1900, 399 Sphaerotilus natans, 717
ideal settling basin theory, 105 description Spiral flow diffusers, 572
removal mathematics, 104–105 attributes, 395–397 Spiral-wound membrane, 545–546, 569
size fraction removal, graphic depiction, of technology, 395 Spore, definition, 717
103–104 design of Standard cell potential, 657
up-flow basins, 105, 132 filter box, 404–406 Standard oxygen transfer efficiency (SOTE), 594
theory, 128 hydraulics, 406–411 Standard values, 774
tube settlers, 127–128 support systems, 411–413 Standard water quality
water and wastewater treatment suspensions, evolution of practice normative, 24
95–96 in America, 398–399 surrogates, 24–25
weir loading rate, 132 in Continental Europe, 398 targets for treatment, 24
Self-backwashing system, filteration, 381–382 in London, 398 types, 22–24
Septum, 423, 438 Worldwide, 398 Static mixers
Settling basins history, 397–399 alum addition, 283
definition, 131 hydraulic conductivities for, 403 baffles, 276, 283–284
design practice influent vs.effluent for, 397 bifurcation effects, 277
basins categories, 114–115 James Simpson and start of, 398 definition, 288
guidelines and criteria, 115–120 materials for, 397 design criteria, 277–280, 283
horizontal flow and up-flow, 115 operation of headloss, 277
primary settling basins, 115–117 monitoring and reporting, 416 principles, 276
detention time, 130 plant start-up, 415 Statistics, 787
discrete particle suspension, 128 tasks involved in, 415–416 Steady state reactor, 66–67
flocculent settling, 129 pilot plant studies of Sterilization, 639
histograms, 129 case study, 414–415 Stokes’ law
horizontal flow, 128, 131 construction, 414 application, 96–97
hydraulics process of equation, 132
computational fluid dynamics (CFD), 114 hydraulics, 401–403 fluid flow, mathematical model, 96
density currents, 113 removal mechanisms, 399–401 Strain, definition, 717
dispersion tests, tracer, 113–114, 132 sand sizes for, 410 Straining, 433, 453
flow patterns and short circuiting, 113 schematic cross section of, 396 Stream aeration, 572