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Technical Description BxFxC = A where B = influent BODS mg/L F = system maximum daily hydraulic flow C = constant of 8.34 A = lbs of BODS entering daily DENITRIFICATION 02 ALLOCATION 4.. The conversion of ammonium to nitrate demands a support process to sustain the reaction. With oxygen being the only common acceptor, Oz demand/delivery is taken into the design consideration �. of the batch process. The energy produced by oxidation ofNH,and NO,is used by nitrifying organisms primarily to pro- duce new biomass.These bacterial cells can be represented by the approximate formula CSH702N.The biomass synthesis reaction for nitrosomonas and nitrobacter is: NH, +HCO3 +4CO2+H2O -> CSH,02N+502 (3) This synthesis reaction requires an input of energy to proceed. During nitrification, this energy is •.. obtained from NH4 and NO2 oxidation equations 1 and 2; therefore, reactions shown in equations 1 and 3 usually occur simultaneously. The energy yield from the oxidation of one mole of NH4 or NO2 is much less than the energy required to produce one mole of bacterial cells as (C51- 70zN). Equations 1, 2, and 3 then must be proportioned so that after energy transfer efficiencies are taken into account, the energy used equals energy produced. The biological nitrification is then expressed as: NH4+ 1.83 02 + 1.98 HCO3 —> 0.021 C5H702N +0.98 NO3+ 1.041 H2O + 1.88 H2CO3 (4) �• which can be used to estimate the three important parameters associated with the nitrification process: oxygen requirements, alkalinity consumption, and nitrifier biomass production. Nitrogen removal is accomplished in the Bio-Pure system without additional equipment or chemicals. Nitrogen enters the system in the raw wastewater in the form of organic nitrogen and ammonia(NH). It is removed from the system in the form of nitrogen gas(N). The actual process by which ammonia nitrogen is converted to nitrogen gas is a three-step process. First is nitrification, the conversion of ammonia nitrogen to nitrite (NO2). Second is the conversion of nitrite to nitrate (NO). Third is denitrification, the conversion of nitrate nitrogen to nitrogen gas (N). All of these steps are accomplished by microbiological action. However, the different steps require different microorgan- isms and different reactor conditions. Steps 1 and 2 both require greater than 0.5 g/m3 dissolved oxygen,take place in the aeration chamber, and occur as an ongoing process. Step 3 occurs in the absence of dissolved oxygen, and since the aeration chamber receives forced air 24 hours a day, takes place in the clarifier.