气升回流一体化中试反应器的污泥减量化

Investigate minimization sludge production for Airlift-Reflux Integrated pilotscale Reactor

为了减少分散型污水处理设施中剩余污泥的产量以及解决其维护频率高和运行设备复杂等问题,开发了一种集去除有机物、脱氮及污泥减量于一体的气升回流一体化反应器。该反应器由缺氧区、好氧区、沉淀区及气升区组成。中试反应器规模为10.31 m^3,以实际生活污水为处理对象,研究其污泥减量机理。结果表明,当进水容积负荷在0.14~1.39 kg COD·(m^3·d)^(-1)之间时,系统对COD、NH_4^+-N、TN及SS的平均去除率分别为88.6%、93%、66.9%和93%,其污泥表观产率系数Yobs为0.139 g TSS·(g COD)^(-1),表明该工艺具有良好的污泥减量化效果。根据稳态—ASM3号模型及氨氮的物料衡算分析可得:通过细胞裂解—隐性生长作用去除的污泥量占反应器污泥减少总量的77.6%,而原生动物和后生动物捕食的污泥量约占系统污泥减少总量的22.4%。该系统污泥自消解速率为0.44 kg TSS·d^(-1)。

The Airlift-Reflux Integrated Reactor,which can remove organic substances,nitrogen nutrients,and reduce sludge production simultaneously,was developed to solve the problems of excessive sludge production,the high maintenance frequency,and equipment complexity in a decentralized sewage system. The system consisted of an anoxic zone,aerobic zone,settling zone,and airlift zone. The capacity of the pilot scale reactor was10. 31 m^3. We studied the mechanism of minimization of sludge production during treatment of actual domestic sewage. The results revealed that when the influent volumetric loading rate was between 0. 14 and 1. 39 kg COD·（ m^3·d）^-1,the system＇s average efficiency of removal of COD,NH4^＋-N,TN,and SS was 88. 6%,93%,66. 9%,and 93%,respectively. The apparent sludge yield coefficient Yobsof this system was found to be0. 139 g TSS·（ g COD）^-1; thus,the system showed good performance in terms of sludge reduction. According to the steady-state ASM3 model and material balance analysis from ammonia nitrogen,the total reduction in sludge production through cell lysis-cryptic growth was 77. 6%; there was approximately 22. 4% reduction in biomass because of predation on bacteria by protozoa and metazoa. The rate of sludge autolysis was 0. 44 kg TSS·d-1 in this system.