【摘要】 通过对两级污泥体积回流比的设置,实现了混合液污泥浓质量度(MLSS)对改良A2O工艺效果影响的研究。当二沉池污泥体积回流比40%,浓缩池污泥体积回流比20%时,MLSS可保持在2 100～2 500 mg/L范围内,COD污泥负荷为0.17 kg/(kg.d),COD、TP、TN以及NH3-N的去除率分别达到78.3%、74.1%、76.2%和100%。适当选取MLSS可同时提高改良A2O工艺对氮和磷的去除效果。由物料衡算发现,厌氧池出水中60.2%的TP和72.9%的TN均通过两级缺氧池去除。尽管只有35.6%的厌氧池出水TP在两级好氧池中继续得到去除,但两级好氧池对上级缺氧池流入的TP去除效率分别高达84.7%和75.0%,对提高TP去除率十分重要。此外,两级好氧池对TN的去除作用不明显,仅为厌氧池出水TN的6.7%。更多还原

【Abstract】 By setting two stage sludge reflux ratios,the effect of mixed liquor suspended solids(MLSS) on the performance of an improved A2O process was studied.When the sludge reflux ratio was 40% for the secondary sedimentation tank,and sludge reflux ratio was 20%,MLSS could be kept in the range of 2 100～2 500 mg/L(sludge loading was 0.17 kg/(kg.d)).The removal rate for COD,TP,TN and NH3-N was 78.3%,74.1%,76.2% and 100%,respectively.By choosing suitable MLSS,the removal efficiency of nitrogen and phosphorus for the improved A2O process were both enhanced.With material balance,it could be found that 60.2% of TP and 72.9% of TN from the effluent of anaerobic tank were removed in tow stage anaerobic tanks.Only 35.6% of TP from the effluent of anaerobic tank was removed in two stage aerobic tanks.However,the removal efficiency of two stage aerobic tanks for TP from the effluent of superior anoxic tanks reached as high as 84.7% and 75.0%,respectively,which was very important for improving TP removal efficiency.In addition,only 6.7% of TN from the effluent of anaerobic tank was removed in two stage aerobic tanks.更多还原