环境工程SMSBR去除焦化废水中有机物及氮的特性.doc

SMSBR去除焦化废水屮有机物及氮的特性 选用一体化膜一序批式牛?物反应器(Submerged Membrane Sequencing Batch Reactor,简称SMSBR)处理焦化废水，考察了能否通过膜分离的强化作用提高生物处理系统 对焦化废水的处理效果，使出水COD达到新的排放标准(100 mg/L),并提岛脱氮效率。 研究结果表明：在HRT为32.7h,平均COD容积负荷为0.45kg/(m3 d)的条件下，出水COD 可以稳定在100 mg/L以下(平均为86.4 mg/L)；要使COD达到新的排放标准，进水COD容 积负荷应低于0.67kg/(m3 d)(该负荷下出水COD在100 mg/L上下波动，平均为106.3 mg/L)； 好氧段存在明S的反硝化现象，使COD的去除得到强化；在保证系统温度、碱度、溶解氧 和不受进水COD负荷冲击的情况下，出水NH3-N可低于1 mg/L,但泥龄太长所产生的微 生物代谢产物抑制了硝化反应过程屮的硝酸盐细菌，使好氧段出水NO2-N/NOX-N平均为 91.1%,因此系统获得极其稳定高效的短程硝化作用，有利于进一步脱氮：按“缺氧1 一好氧 一缺氧2”方式运行时，若“缺氧2”的HRT〉8.44 h,可实现81.34%的反硝化率(外加碳源： COD/N为2.1 g/g),平均TN去除率为87.2%,最高达90.2%。 关键词：SMSBR焦化废水有机物脱氮 Characteristics of Submerged SMSBR in Removal of Organic Matters and Nitrogen from Coke Plant Wastewater Abstract： A SMSBR was used for treating coke plant wastewater and enhanced effects of membrane separation on the treatment efficiencies were investigated.The purpose of the study was to make effluent COD meet the new discharge standard( 100mg/L),and increase the removal efficiency of nitrogen.The result shows that effluent COD is steadily below 100 mg/L (86.4 mg/L on the average) at the HRT of 32.7 h and the COD volume loading rate of 0.45kg/(m3 d).To reach the new effluent discharge standard,COD volume loading rate should be lower than 0.67kg/(m3 d).In this condition effluent COD fluctuates around 100 mg/L (106.3 mg/L on the avcragc).Thc COD removal is enhanced by denitrification appearing in the aerobic stage.The effluentNH3-N is lower than 1 mg/L when temperature, alkalinity，and dissolved oxygen in the system are under control and there is no COD shock-load.NO2-N/NO3-N in the effluent from the aerobic stage is 91.1% on the average because nitrifers in nitrification process are inhibited by the metabolic products of microorganisms due to long sludge age. This shows that short-cut nitrification/dcnitrification is obtained with high efficiency and stability in the system, and is benefit for further removal of nitrogen.SMSBR system operates in anoxic-aerobic-anoxi