MBR中SMP与污泥特性之间的相关性

Relation of Soluble Microbial Product Versus Sludge Properties in Membrane Bioreactor

以模拟生活污水为研究对象,在膜通量恒定的条件下,考察了MBR(Membrane Bioreac-tor)内SMP(Soluble Microbial Product)的积累与污泥特性之间的相关性.结果表明,SMP可以被微生物降解,SMP的浓度在反应器中呈先增加后降低.最终趋于稳定的变化趋势,并最终达到其产生—降解的动态平衡.反应器运行初期,絮状污泥的VSS/SS、污泥比基质降解速率、OUR和SVI迅速下降,分别由初始的0.913、0.72 kg/(kg.d)、6.78 mg/(g.d)和108降至第24天的0.72、0.187 kg/(kg.d)、3.74 mg/(g.h)和43,之后缓慢上升,至第40天左右时基本趋于稳定,但均低于初始值.MBR中SMP的积累与污泥特性密切相关,SMP的积累降低了污泥的沉降性能和单位质量污泥的微生物含量及其代谢活性,在膜的截留作用下,系统对污染物的总体去除率未因此而受到影响,系统运行稳定.

Domestic wastewater was treated by an integral membrane bioreactor （MBR） under stable membrane flux. Relation of soluble microbial product and sludge properties was investigated during the domestic wastewater treatment by MBR. The results showed that the concentration of SMP in MBR firstly increased, and then declined. SMP can be biodegraded by microorganisms, and its concentration finally reached dynamic equilibrium in MBR. VSS/SS, specific substrate degradation rate, OUR and sludge volume index （SVI） declined during the first 24 days from the beginning values of 0.913, 0.72, 6.78 and 108 to 0.72, 0.187 kg/（kg · d）, 3.74 mg/（g · h） and 43, respectively. Afterwards, their values increased slowly and almost stayed at constant after 40 days, but less than the beginning values. In a word, as the concentration of SMP increased, the sludge activity and settling performance were deteriorated before 40 days, and then remained at steady-state. As a result of membrane cut-off, the organic substances as well as nitrification and de nitrification bacteria were effectively kept in MBR, the accumulation of SMP had little influence on the removal efficiency of COD and ammonia nitrogen.