得利满手册.AEROBIC BIOLOGICAL PROCESSES

得利满.AEROBIC BIOLOGICAL PROCESSES11AEROBICBIOLOGICALPROCESSES1.ACTIVATEDSLUDGE1.1INSTALLATIONLOADINGANDOPERATIONALCHARACTERISTICSThepurificationefficiencyofanactivatedsludgeplantdependsontwofactorssimultaneously:-fixing,byadsorptionandoxidation,ofthepollutingelementsbythebacterialmass(orbiologicalfloc),-effectiveseparationofthisflocfromthepurifiedinterstitialwater.Intheactivatedsludgereactor,bacterialmassisaccumulatedduetosludgerecycling;sludgeagethusincreaseswiththeavailablebiomassquantityandhasasomewhatslowingeffectonthebacterialactivity;however,inthedevelopmentphase(seepage297)whichisthephaseofmostofthebacterialflora,thiseffectisnotpredominantand,generallyspeaking,thequantityofpollutionretainedisallthegreaterbecausethebacterialmassisconsiderable.Forcontinuousremovalofthesolublecarbonaceouspollution,thepurificationefficiencyisgreaterthelowertheF/Mratio(seepage296)andthegreaterthesludgeage.Thismightnotbethesameforconcomitantnitrificationorphosphateremoval.Purificationprocessesbyactivat