CIVIL ENGINEERING FORMULAS

362 CHAPTER THIRTEEN wherencoefficient dependent on roughness of conduit surface Rhydraulic radius, ft area, ft^2 , of fluid ...

STORMWATER, WASTEWATER, AND ENVIRONMENTAL PROTECTION 363 When a grate inlet is used to collect the storm water, an opening of 18 ...

364 CHAPTER THIRTEEN wherellength of weir, ft hdepth of flow over weir at down-stream end, ft Siphon spillways are better adap ...

STORMWATER, WASTEWATER, AND ENVIRONMENTAL PROTECTION 365 whereVrreactor volume (Mgal) (m^3 ) (^) cmean cell residence time, or ...

366 CHAPTER THIRTEEN It is recommended that aeration equipment be designed with a factor of safety of at least 2. The food to mi ...

STORMWATER, WASTEWATER, AND ENVIRONMENTAL PROTECTION 367 Xmixed liquor suspended solids (MLSS) Qrreturn activated sludge pumpi ...

368 CHAPTER THIRTEEN The ratio of RAS pumping rate to influent flow rate, or recirculation ratio (), may now be calculated: (13 ...

STORMWATER, WASTEWATER, AND ENVIRONMENTAL PROTECTION 369 SIZING A POLYMER DILUTION/FEED SYSTEM Depending on the quality of settl ...

370 CHAPTER THIRTEEN The sludge feed rate for the dewatering facility is (13.35) And the sludge weight flow rate is (13.36) Wsw ...

STORMWATER, WASTEWATER, AND ENVIRONMENTAL PROTECTION 371 The wet cake discharge (lb/h) is (13.39) The volume of wet cake, assumi ...

372 CHAPTER THIRTEEN The NRC equations for trickling filter performance are empirical equations, which are primarily applicable ...

STORMWATER, WASTEWATER, AND ENVIRONMENTAL PROTECTION 373 whereRrecirculation ratio Qr/Q Qrrecirculation flow Qwastewater flo ...

374 CHAPTER THIRTEEN The power input per volume of liquid is generally used as a rough measure of mixing effectiveness, based on ...

STORMWATER, WASTEWATER, AND ENVIRONMENTAL PROTECTION 375 The weight of oxygen, (lb 2 /day) required to destroy the VSS is approx ...

376 CHAPTER THIRTEEN Adjustment for depth. The treatability constant is then adjusted from the standard depth of 20 ft (6.1 m) t ...

STORMWATER, WASTEWATER, AND ENVIRONMENTAL PROTECTION 377 achieve uniform growth and sloughing, higher periodic dosing rates are ...

378 CHAPTER THIRTEEN In the anaerobic digestion process, the organic material is converted biologi- cally, under anaerobic condi ...

STORMWATER, WASTEWATER, AND ENVIRONMENTAL PROTECTION 379 wherePxvolatile solids produced, lb/d (kg/d) Yyield coefficient (lb V ...

380 CHAPTER THIRTEEN The average daily consumption of chlorine is Cl 2 lb/d(average dosage, mg/L) (Mgd)(8.34) (13.77) A typical ...

STORMWATER, WASTEWATER, AND ENVIRONMENTAL PROTECTION 381 To size the main and lateral sewers, use the Manning formula and the ap ...