长泥龄剩余污泥的中温水解研究

Mesophilic Hydrolysis Characteristics of Excess Sludge with Long SRT

为了保证低温等不良条件下活性污泥系统出水氮浓度的达标排放,维持较长的泥龄(SRT)是污水处理厂运行管理中经常采取的策略,但该时期的污泥是否应该进入中温水解或消化系统却是一个值得商榷的问题。以SRT>25 d的剩余污泥为研究对象,通过序批式试验探讨了其水解特征及可能的水解速率促进措施。结果表明,从污泥减量及获取溶解性有机物(SCOD)的角度来看,SRT>25 d的剩余污泥其中温水解效果不佳,资源化利用价值不大。另一方面,采取生物强化的方法可提高长泥龄污泥的水解速率,其中,TSS减量率为控制反应器的3.11倍、VSS减量率为控制反应器的2.88倍、SCOD的溶出速率为控制反应器的1.14倍。

Keeping a longer sludge retention time （SRT） in the activated system is an efficient strategy to ensure the up-to-standard discharge of nitrogen in effluent under the adverse operation conditions such as low temperature in WWTP. However whether the sludge with long SRT should enter the digester to be hydrolyzed or digested is still an open question. Investigations in a sequencing batch reactor were carried out aiming to describe the hydrolysis characteristics of excess sludge with long SRT of more than 25 days and find a possible method to improve the hydrolysis rate. The results show that from the point of view of sludge reduction and acquisition of dissolved organic matter, it is not suitable to be hydrolyzed or used as resource when SRT of activated sludge exceeds 25 days. On the other hand, it is a feasi- ble method to improve hydrolysis rate of sludge with long SRT using bioaugmentation, by which the reduction rates of TSS, VSS and the production of SCOD are 3.11, 2.88 and 1.14 times of the control reactor respectively.