【摘要】 污泥淤沙分离器能够分离去除活性污泥中的细微泥沙,提高活性污泥的MLVSS/MLSS值,有利于污水处理系统的稳定运行。通过向生化池污泥混合液中投加不同粒径的细微泥沙,研究了细微泥沙的悬浮时间对污泥淤沙分离性能及其悬浮态势的影响,为污泥淤沙分离系统运行模式的设置提供理论基础。结果显示,粒径>33μm的细微泥沙呈自由悬浮态势,不受悬浮时间的影响;14μm<粒径≤33μm的细微泥沙在初期呈自由悬浮态势,悬浮15 d后呈卷捕附着态势;粒径≤14μm的细微泥沙进入生化池后,快速被活性污泥絮体卷捕。粒径为33μm的细微泥沙被污泥絮体卷捕后,分离器的分离度、除沙效率分别降低了41.0%、30.4%,表明细微泥沙呈卷捕附着态势不利于污泥淤沙分离。由于细微泥沙主要由降雨径流带入,因此降雨期及降雨后的一段时间应运行污泥淤沙分离系统,避免14μm<粒径≤33μm的细微泥沙被活性污泥絮体卷捕,降低了淤沙分离效果。更多还原

【Abstract】 Silt-sludge separator can separate and remove fine silt from activated sludge,and improve the MLVSS/MLSS value of activated sludge,which is conducive to the stable operation of wastewater treatment plants(WWTPs).By adding fine silt with different particle sizes into activated sludge in bioreactors,the effect of suspension time of fine silt on the performance of silt-sludge separator and suspension modes of fine silt was investigated to provide theoretical basis for the operation modes of silt-sludge separation system.The results showed that fine silt with a particle size of more than 33 μm was freely suspended in activated sludge and the suspension time had no impact on its suspension modes.Fine silt with a particle size of 14 μm to 33 μm was freely suspended in activated sludge during the early stage,but it was picked up and bound by activated sludge flocs after 15 d.Once fine silt with a particle size of less than or equal to 14 μm was suspended in activated sludge,it was quickly picked up and bound by activated sludge flocs.After fine silt with a particle size of 33 μm was bound,the separation degree and silt removal efficiency of the separator were reduced by 41.0% and 30.4% respectively.It was revealed that pick-up and binding of fine silt had negative effect on the silt-sludge separation.As fine silt in WWTPs was mainly brought in by storm runoff,silt-sludge separators should be operated during and after storms to avoid the binding of freely suspended fine silt with the particle size of 14 μm to 33 μm by activated sludge flocs and the decreased efficiency of silt-sludge separator.更多还原