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Technical Description C = constant of 8.34 A = lbs of BODS entering daily DENITRIFICATION 0,ALLOCATION The conversion of ammonium to nitrate demands a support process to sustain the reaction. With oxygen being the only common acceptor, 02 demand/delivery is taken into the design considera- tion of the batch process. The energy produced by oxidation of NH., and NO, is used by nitrifying organisms primarily to produce new biomass. These bacterial cells can be represented by the approximate formula C5H70,N.The biomass synthesis reaction for nitrosomonas and nitrobacter is: NH4+ HCO3 +4CO, + H2O C5H702N + 502 (3) This synthesis reaction requires an input of energy to proceed. During nitrification. this energy is obtained from NH., and NO2 oxidation equations I and 2; therefore, reactions shown in equations I and 3 usually occur simultaneously. The energy yield from the oxidation of one mole of NH, or NO, is much less than the energy required to produce one mole of bacterial cells as (C5H702N). 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: NH,+ 1.83 02+ 1.98 HCO; 0.021 CIH702N+ 0.98 NO, + 1.041 R20+ 1.88 H,CO, (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 Nitro-Raptor system without additional equipment or chemicals. Nitrogen enters the system in the raw wastewater in the form of organic nitrogen and ammonia (NH4). It is removed from the system in the form of nitrogen gas (N2). The actual proc- ess by which ammonia nitrogen is converted to nitrogen gas is a three-step process. First is nitri- fication, the conversion of ammonia nitrogen to nitrite (NO2). Second is the conversion of nitrite. to nitrate (NO3). Third is denitrification, the conversion of nitrate nitrogen-to-nitrogen gas (N2). All of these steps are accomplished by microbiological action. However, the different steps re- quire different microorganisms 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. Nitrogen removal in the 'vitro-Raptor process is considerably greater than that of flowthrough and single-tank, sequencing-batch reactor systems. The Nitro-Raptor system achieves an average of 96.4%total nitrogen removal. AERATION DETENTION The Nitro-Raptor system's superior low-sludge-producing performance is obtained, in pan, by combining the complete-mix hydraulic design with the detention times of the extended-aeration designs. This combination effectively produces a low F:M ratio and a subsequent high MCRT. This promotes the development of specific, high-process microorganisms. - ]1 - 7-H Technical Services Group,Inc. i