高效厌氧氨氧化颗粒污泥膨胀床(EGSB)工艺性能研究

Performance of the Anammox process in an expanded granular sludge bed(EGSB) reactor with high load

采用模拟含氨废水和颗粒污泥膨胀床(EGSB)反应器研究了厌氧氨氧化工艺的高效性能.试验结果表明,厌氧氨氧化EGSB工艺具有很高的容积效率,在35℃、进水氨氮浓度247.1～444.8mg·L-1、亚硝氮浓度为308.7～483.8mg·L-1的条件下,反应器水力停留时间可缩至0.237～0.267h,平均容积去除速率可高达61.4kg.m-.3d-1(以N计).同时,该工艺具有超常的运行稳定性,在进水基质浓度、进水流量和pH波动的情况下,总氮去除率和出水浓度的相对标准偏差分别为3.6%～6.9%和14.4%～22.6%.厌氧氨氧化EGSB工艺的高效稳定性可归因于反应器的强污泥持留能力和厌氧氨氧化污泥的高反应活力.系统内持留的污泥浓度高达24～28g·L-1(以VSS计),分批培养测得的最高比污泥活性为2.19g.g-1.d-1(以N计),连续培养测得的最高比污泥活性为3.62g.g-.1d-1(以N计).

The anammox （anaerobic ammonia oxidation） process was investigated at 35℃ in an expanded granular sludge bed （EGSB） reactor fed with synthetic wastewater. The results showed that it was a highly efficient process for nitrogen removal. The hydraulic retention time of the EGSB reactor was between 0.237 h and 0.267 h. When influent concentrations of ammonium and nitrite were increased from 247.1 to 444.8 mg·L-1 and from 308.7 to 483.8 mg·L-1 respectively,the average volumetric nitrogen removal rate was elevated up to 61.4 kg·m-3·d-1（N）. During the operation,the relative standard deviations of effluent substrate concentration and nitrogen removal efficiency were 14.4%~22.6% and 3.6%~6.9%,respectively,in spite of fluctuation of influent concentration,flow rate or pH. The stability of the process performance could be attributed to both the efficient retention of granular sludge （24~28 g·L-1 （VSS）） and the high specific activity of biomass （2.19 g·g-1·d-1（N） determined from batch assay and 3.62 g·g-1·d-1（N） from continuous cultivation）.