膜-生物反应器处理超市废水中污泥性质与膜污染关系分析

Correlation between membrane fouling and characteristics of sludge in a membrane bioreactor treating wastewater from supermarket

在以处理超市废水实际工程的基础上,通过对污泥性质中的胞外聚合物(EPS)、溶解性微生物产物(SMPs)、溶解性COD(SCOD)和污泥浓度(MLSS)变化的分析,得出EPS积累的原因是多方面的,而EPS的过度积累对沉降性能有一定的恶化作用;此外,EPS与SMPs有很好的相关性。作者采用SPSS软件对污泥性质与膜污染之间的关系进行了分析,结果表明,EPS、SMPs、SCOD、MLSS两两之间有很好的相关性;同时,得出SMPs对膜污染影响最重要,其次是EPS、SCOD,而MLSS与膜污染没有显著相关性;然而,偏相关分析显示,EPS、SMPs、SCOD、MLSS与dTMP/dT都没有显著的独立相关性。以上结果表明,膜污染不是某种属性单独作用的结果,而是由污泥各种属性共同作用的结果。

On the basis of a full-scale submerged membrane bioreactor（MBR） for the treatment of wastewater from supermarket,the variation of extracellular polymer substances（EPS）,soluble microbial products（SMPs）,soluble chemical oxygen demand（SCOD） and mixed liquor suspended solid（MLSS） in the mixed liquor were investigated.It was found that the accumulation of EPS which was triggered by several reasons had negative effects on the settleability of sludge.Moreover,the variation of SMPs had good relationships with the variation of EPS hydrolyzed by microorganisms.The statistical analysis software（SPSS） was introduced to specify the correlation between membrane fouling and the characteristics of sludge.It showed that the correlation between each two different characteristics of sludge including EPS,SMPs,SCOD,MLSS was good.Meanwhile,the result indicated that SMPs had the most important impact on the membrane fouling,followed by EPS and SCOD,while MLSS had no significant correlation with the membrane fouling.However,according to the partial correlation analysis,there were no significant correlations between characteristics in the mixed liquor and membrane fouling,which implied that the factors could not affect membrane fouling independently.Therefore,it was demonstrated that membrane fouling was a complex process which was caused by the combined effects of several different characteristics.