电化学预处理提高剩余污泥好氧消化性能研究

Enhancement of waste activated sludge aerobic digestion by electrochemical pretreatment

采用电化学方法对好氧消化处理前的剩余污泥(以下简称污泥)进行预处理,考察了不同预处理条件对污泥有机物(以MLVSS来表征)的去除效果,探讨了电化学预处理对污泥好氧消化效率的影响。结果表明,以网状钛涂钌电极板为电极,在pH为11.00,极板间距为2.0cm,工作电压为15V,气体搅拌作用下电解30min后,污泥(初始质量浓度为20.04g/L)的MLVSS去除率达9.7%。污泥经过电化学预处理后,在自然温度(10～15℃)下进行好氧消化处理,14d后MLVSS去除率达40.1%,而同期未经预处理的污泥MLVSS去除率为33.2%,并于20d后达40.2%。经电化学预处理后污泥的好氧消化效率显著提高,大大缩短了污泥好氧消化的时间。

Batch of electrochemical experiments were performed on waste activated sludge （WAS） to investigated the effect of p H, voltage, polar plate spacing,initial concentration of sludge and reaction time on WAS degradation efficiency. The electrochemical treated WAS was applied for aerobic digestion at natural temperature （10-15 ℃ ）. The results showed that under the optimum operating conditions of pH was 11.00, polar plate spacing was 2.0 cm and voltage was 15 V and 30 min of electrochemical pretreatment with RuO2/Ti polar plates, the mixed liquor volatile suspended solid （MLVSS） removal rate of WAS （20.04 g/L） reached to 9.7 %. The treated WAS presented perfect aerobic digestion efficiency with MLVSS removal rate reached to 40.1% after 14 d of aerobic digestion,which was higher than that of un-pretreated WAS （33.2%）. Finaly, the mechanism of electrochemical for WAS aerobic digestion enhancement was given.