污泥淤砂分离器对分离分流污泥性质的影响

为解决我国很多城镇污水厂活性污泥的MLVSS/MLSS普遍偏低,污泥中泥沙淤积严重的问题,根据水力旋流器的分离原理,开发了污泥淤砂分离器,实现污泥中生物基质和淤砂的分离分流,研究污泥淤砂分离器主要结构参数排口比(底流口直径/溢流管直径)对分离分流污泥性质的影响。实验结果表明,排口比为0.4时,污泥经过污泥淤砂分离器后,得到的底流污泥MLVSS/MLSS比原污泥减小了34%,溢流污泥MLVSS/MLSS增大了16.8%,污泥中的生物基质富集在溢流污泥中,淤砂富集在底流污泥中;底流污泥浓度MLSS比原污泥增加了2.6倍,底流污泥SVI和CST分别减小了68%和70%,底流污泥浓缩效果明显,沉降性能和脱水性能大幅提高,有利于底流污泥的处理处置;进一步减小排口比,底流污泥浓缩效果、沉降性能和脱水性能均进一步提高。

Effects of sludge-grit separator on properties of separated sludge

As much grit is collected in activated sludge,MLVSS/MLSS of activated sludge is quite small in many wastewater treatment plants in China.In order to solve this problem,sludge-grit separator was developed based on the principle of hydrocyclone,which was used to achieve the separation of grit and biomass.We present the study of the effect of outlet ration,which is one of the key structure parameters of sludge-grit separator and defined as the ratio of underflow diameter to overflow diameter,on properties of underflow sludge and overflow sludge.The results show that when the outlet ratio is 0.4,MLVSS/MLSS of underflow sludge is reduced by 34% and MLVSS/MLSS of overflow sludge increase by 16.8%,compared with that of raw sludge.It is indicated that grit is collected in underflow sludge and biomass is collected in overflow sludge.Compared with those of raw sludge,the sludge concentration MLSS of underflow sludge is raised by 2.6 times,SVI and CST of underflow sludge decrease by 68% and 70%, respectively.It is showed that the condensed effect of underflow sludge is obvious,and the settleability together with the dewaterability of underflow sludge are also improved.What's more,when the outlet ratio declines,the condensed effect of underflow sludge is more obvious,and the settleabiltiy together with the dewaterability of underflow sludge are further improved.