污泥转移对SBR工艺微生物群落结构及其除磷效能影响分析

采用污泥转移SBR工艺处理以生活污水为基础的合成废水。污泥转移能够强化厌氧生物选择器中聚磷菌的筛选,从而显著提升传统SBR工艺的除磷性能。对比传统SBR,应用荧光原位杂交(FISH)和聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)考察了污泥转移SBR中微生物种群结构的变化及除磷特性。结果表明,污泥转移SBR中磷的去除率总体呈上升趋势,稳定在93%左右;而传统SBR中磷的平均去除率为50%。DGGE试验表明,污泥转移SBR首尾样品的相似性系数为36.8%,传统SBR的则为54.7%;污泥转移SBR的香农指数下降率为5.6%,而传统SBR的香农指数下降率为4%。微生物种群在驯化过程中发生了变化,即微生物种群的优势菌在反应器启动阶段被筛选和富集。对比传统SBR,污泥转移SBR中微生物种群的这一驯化现象表现得更为明显。FISH试验表明,污泥转移SBR的聚磷菌占全菌比例在反应器稳定后可达到46%,聚糖菌则稳定在22%;传统SBR稳定后的聚磷菌比例为35%,聚糖菌比例为30%。传统SBR和污泥转移SBR的聚磷菌比例都先沿程增加最后稳定,且聚磷菌是优势菌。污泥转移SBR的聚糖菌沿程减少,聚磷菌抑制了聚糖菌的生长。因此,污泥转移SBR工艺具有筛选大量聚磷菌且抑制聚糖菌的除磷优势。

Analysis of the effect of sludge shifting volume on the microbial community composition and the phosphorus removal in the SBR process

The given paper is aimed at making an investigation and analysis of the effects of sludge shifting volume on the microbial community composition and phosphorus removal in the SBR process for the domestic sewage treatment.As compared with the traditional SBR,we have been making efforts to improve the removal efficiency of the pollutants via the sludge shifting through strengthening the screening of phosphorus accumulating organisms (PAOs) in the anaerobic biological selector.In doing so,we have analyzed the effect of the sludge shifting volume on the microbial community structure and the characteristic features of the phosphorus removal,finding that it is possible to increase the removal rate of phosphorus in sludge-shifting SBR process by about 93％,against the 50％ of the average removal rate of phosphorus in the traditional SBR approach.Thus,the results of the DGGE have made it clear that the sample similarity coefficient between the beginning stage and the finishing stage of the sludge-shifting SBR may account for 36.8％.And,in contrast,the rate of decline of Shannon index in the sludge-shifting SBR has been found equal to 5.6％ against the 4％ of the declining rate of Shannon index in the traditional SBR approach.What is more,the microbial population tends to have changed in the domesticating process both in the sludge-shifting SBR and the traditional SBR approach apart from that the dominant bacteria has been made screened and enriched at the beginning stage.Hence,as against the traditional SBR,the sludge-shifting SBR rate proves to be more obvious through domestication.The results of the FISH experiment prove that,the population of PAOs can be made to reach 46％ whereas the population of glycogen aggregation organisms (GAOs) can be made to reach 22％ in the plateau stage of the sludge shifting SBR.Just for the reason,the population of PAOs can be expected to reach 35％ while that of GAOs can only be made to get to 30％ in the plateau stage of the traditional SBR.Thus,the content rate of PAOs both in the traditional SBR and the sludge-shifting SBR can all be made to increase at the starting-up stage until getting to its final stability.And,that is how the PAOs trends to be more often used as the dominant advantageous bacteria.Therefore,as the content rate of GAOs tends to decrease with the going on of the sludge-shifting SBR,the accumulation of PAOs would be likely to inhibit the growth of GAOs.And,thus,the sludge-shifting SBR process can naturally be expected to enjoy a great priority in screening and accumulating a great lot of PAOs.