AB工艺减少污泥重金属的效果

在AB工艺中,利用A段活性吸附去除重金属从而降低B段污泥中重金属含量,使其达到农用标准（GB4284-84酸性土壤控制标准）。利用小型污水处理实验场,模拟研究了AB工艺A段中重金属的去除情况,对AB运行控制参数进行优化探讨,以使A段能有效去除大部分重金属,并尽可能降低有毒有害污泥产量。结果表明：溶解氧质量浓度控制在0.5mg·L-1,污泥质量浓度调节为约500mg·L-1时,Cu2＋去除率可达87.6%,Zn2＋的去除率为78.7%,Ni2＋去除率为51%。当污泥质量浓度在1000～1500mg·L-1时,A段处理后污泥沉降性能好转,对重金属离子的去除有较好的效果,且不过多截留污水中的有机物。且B段剩余污泥中的Cu2＋、Zn2＋、Ni2＋含量都基本达到酸性土壤污泥农用控制标准。因此,适当控制AB工艺相关参数条件,利用A段活性污泥去除大部分重金属,降低B段产泥中重金属含量,达到农业控制标准是可行的,污泥经处理后进行土地资源化利用可成为我国污泥处置与利用的一种有效途径。

Effects of reducing heavy-metal in waste actived sludge through A-B Process (Adsorption-Bio-Activated Sludge Process)

In this study, heavy metals were removed from sewage and reducing sludge by A part of AB process, so that it could reach the standard of agricultural use (GB 4284-84) in B process. A asimulating experiment in miniature was used for researching how to effectively removed heavy metal during A and optimized operational parameter in A-B process. The results show that the removal rate of Cu~(2+)、Zn~(2+)、Ni~(2+) can reach 87.6%、78.7%、51% respectively, when the dissolved oxygen is 0.5 mg·L~(-1) and the sludge concentration is about 500 mg/L. When the sludge concentration is 1000～1500 mg·L~(-1), the settling property of the sludge is improved after A process. It also can effectively remove heavy metal and preserve organic matter from the waste water. In the B process, the concentration of Cu~(2+)、Zn~(2+)、Ni~(2+) in the residual sludge can reach the standards of acidic soil sludge control on the whole. Therefore, it is feasible to satisfy the standards of agriculture control by controlling the parameters of A-B process. And it could become a effective way of disposing and utilizing sludge through the treated sludge utilization.