A^2/O工艺的旁路化学除磷及污泥减量研究

Bypass Chemical Phosphorus Removal and Sludge Reduction in A^2/O Process

为了确保脱氮除磷效果并降低剩余污泥产量,在A2/O系统的污泥回路上增加厌氧/好氧交替污泥减量池,并对部分厌氧释磷液实施旁路化学除磷。结果表明,在A2/O系统中接入污泥减量装置后,污泥表观产率为0.278 gMLSS/gCOD,污泥产量降低了37.9%;系统出水TN≤14.6 mg/L、TP≤1.31 mg/L,与常规A2/O工艺相比,对TN的去除率提高了3.84%,但对TP的去除率降低了2.87%。在A2/O系统中接入污泥减量装置并辅以旁路化学除磷后,系统出水COD≤55 mg/L、TN≤14.6 mg/L、TP≤0.70 mg/L,出水水质达到了《城镇污水处理厂污染物排放标准》(GB 18918—2002)的一级B标准,并实现了污泥减量的目的。

In order to ensure the effective nitrogen and phosphorus removal and reduce sludge production, an alternative anaerobic/aerobic sludge reduction tank was added in the sludge return circuit of A2/O process, and the bypass chemical phosphorus removal from partial anaerobic phosphorus release liquor was performed. The results show that after addition of sludge reduction device in the A2/O process, the apparent yield rate of sludge is 0. 278 gMLSS/gCOD, and the sludge production is decreased by 37.9%. The effluent TN and TP are equal to or less than 14.6 mg/L and 1.31 mg/L respectively, and the removal rate of TN is increased by 3.84% , but the removal rate of TP is decreased by 2.87% compared with the conventional A2/O process. After addition of sludge reduction device and bypass chemical phosphorus removal in the A2/O process, the effluent COD, TN and TP are equal to or less than 55 mg/L, 14.6 mg/L and 0.70 mg/L respectively. The effluent quality meets the first level B criteria specified in the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant （GB 18918 -2002） , and the goal of sludge reduction is achieved.