Study On Effectiveness Of Deammonification Reactor Based On Biofilm

Untreated emissions of nitrogen-rich wastewater such as municipal sewage, pesticides irrigation, aquaculture untreated wastewater is a major factor in causing eutrophication, irrigation water of pesticide residues, aquaculture wastewater is a major factor in causing eutrophication. With the development of urbanization, municipal sewage has accounted for the largest proportion of wastewater discharge in our country. Traditional biological nitrogen removal processes often have the disadvantages of low efficiency with high-energy consumption and large area. Therefore, the development of new low carbon nitrogen removal process can remove nitrogen and reduce energy consumption effectively, which is important to wastewater treatment.Biofilm technology is considered to be a highly efficient method of wastewater treatment, it has advantages of large biomass, processing capability, less excess sludge production, convenient operation and management compared with the activated sludge process. Sequencing batch biofilm reactor (SBBR) is one of complex biofilm reactors based on biofilm technology; it inherits the advantages of biological membrane method, and combined the running characteristics of SBR reactor. It inherits the advantages of the biofilm technology, but also combines the operating characteristics of SBR reactor.In this study, a comparative study about packing configuration of SBBR reactor was conducted to determine an optimization. A combination of SBBR and upflow biofilm reactor was used to analyze the denitrification performance and system stability to simulate municipal sewage using semi-nitrification-anaerobic ammonium oxidation process by a combination of SBBR reactor with upflow biofilm reactor.Firstly, to determine the best filling way and best fill rate of the SBR reactor packing with simulate actuaL wastewater. The results showed that under the temperature of (29±1)℃,the reactor was started with ZH filler at 20% filling rate, the time of biofilm matured by fixed filling way was 8d earlier than the suspended filling. The removal rates of ammonia nitrogen and COD was 84.01% and 86.83% respectively in the way of natural suspended filling,the other way was 98.07% and 95.23% respectively. The COD and nitrogen removal effects of the fixed filling way were better than the suspended filling. The removal rate of COD was 95.23% which was 1.10 and 1.04 times of 40% and 60% of filling rate; the removal rate of ammonia nitrogen was 98.07%which was 1.39 and 1.69 times of the other two conditions.Semi-nitrification was achieved in SBBR with 20% filling rate by fixed filling way. After 122d of the sludge cultivation and 42d biofilm cultivation, nitrite accumulation efficiency was 93.2%, and the nitrate nitrogen was below detection limit, ammonium was partly oxidized to nitrite with an ammonium:nitrite ratio of 1:0.71.ANAMMOX has become the dominant reaction after 74d cultivation of upflow biofilm reactor. The average removal rate of NH4+-N and NO2--N in effluent reached 91.03% and 86.56% respectively, the removal load were 8.53kg/(m3d) and 9.29 kg/(m3d),the removal ratio of ammonia and nitrite nitrogen was 1.33.The combined process was coupled with successfully launched SBBR reactor and upflow biofilm reactor. Effluent NH4+-N of the combined treatment process was less than 5mg/L. Due to the influence of nitration, effluent NO2--N and NO3--N were 20mg/L and 40mg/L respectively. The N convert rate of SBBR was 38.51% while anaerobic ammonium oxidation (ANAMMOX) reactor, the major system in nitrogen removal, which removed of 52.39% N.