生物接触氧化法的同步硝化反硝化影响因素研究

Influencing Factors of Simultaneous Nitrification and Denitrification in Biological Contact Oxidation Process

研究了生物接触氧化法同步硝化反硝化系统中HRT、DO、COD及生物膜厚度对脱氮效率的影响。结果表明:在DO=2.0 mg/L的条件下,出水COD、TN、NH4+-N值随HRT的增加呈下降趋势,在HRT达到8 h时,出水COD、TN、NH4+-N值趋于稳定,去除率分别为94%、55.9%和73.3%;在DO为2.0～4.0 mg/L范围内,对TN的去除率随着反应器内DO浓度的降低呈上升趋势,保持较好脱氮率的溶解氧为2.5～3.0 mg/L;进水COD为400 mg/L时,系统对TN、NH4+-N的去除率及容积去除率都处在较高水平,对TN的平均去除率达到60%;生物膜厚度对同步硝化反硝化有较大影响,增加生物膜厚度有利于同步硝化反硝化的进行。

The effects of HRT, DO, COD and biofilm thickness on nitrogen removal efficiency of simultaneous nitrification and denitrification system in biological contact oxidation process were investigated. The results show that when DO is 2.0 rag/L, the effluent COD, TN and NH4＋ - N are reduced with the increase of HRT and are stable with the removal rates of 94% , 55.9% and 73.3% when the HRT reaches 8 h. The removal rate of TN is increased with the decrease of DO from 4.0 to 2.0 mg/L in the reactor, and the DO for keeping a better nitrogen removal rate is 2.5 to 3.0 mg/L. The removal rates and volumetric removal rates of TN and NH4＋ - N are at high level when the influent COD is 400 mg/L, and the average removal rate of TN is about 60%. The biofilm thickness has great influence on the simultaneous nitrification and denitrification in the system. The increase of biofilm thickness is beneficial for simultaneous nitrification and denitrification.