中文摘要：

采用序批式投加剩余污泥方式，连续34d考察了膜生物反应器（MBR）工艺的污泥减量效果，研究了MBR中微型动物种类与数量的变化规律以及生物捕食作用对污泥减量效果的贡献。研究发现，MBR中出现密度较高的原生动物和后生动物共13种，其中以红斑顠体虫平均密度最高，达到了338．5个／mL；MBR在运行过程中，MBR内的微型动物呈现出“纤毛虫-轮虫-红斑顠体虫”的演替变化规律；MBR内的污泥减量效果与微型动物的种类和数量有关，在试验初始阶段。MBR内污泥质量保持相对稳定，之后随着MBR内红斑顠体虫的快速增殖，开始大量生物捕食其他原生动物和轮虫，MBR内微型动物总量降低，导致试验后期（运行约20d后）MBR内的污泥质量迅速增加，可见保持MBR内原生动物和后生动物种类与数量的相对稳定是MBR工艺能够长期实现污泥减量的关键。整个试验期间，向MBR中投加的待处理污泥总量为126．9g，污泥累积减少量为100．2g，污泥总减量率为78．96％，其中生物捕食作用引起的污泥累积减少量占总的污泥累积减少量的73．9％，是MBR工艺实现污泥减量的主要贡献者。

英文摘要：

Supplementing untreated sludge in a sequencing batch way was adopted to study sludge reduction in a submerged membrane bioreactor （MBR）. The variations of microfauna and sludge concentration was investigated for 34 days in this research in order to understand the microfauna community dynamic in the MBR and to estimate the contribution of microfauna predation for the sludge reduction. Thirteen species of protozoa and metazoa were observed with high population density,in which Aeolosoma hemprichii Ehrenberg was the dominant with a density of 338.5 in- dividual per milliliters. The succession of the dominant microfauna groups in the reactor was as following： Ciliated protozoa-Rotaria-Aeolosoma hernprichii Ehrenberg. The sludge reduction was found to be closely related to the struc- ture of the microfauna community. In the starting period,the sludge mass kept stable. After 20 days, the sludge mass in the reactor increased significantly due to the growth of Aeolosoma hemprichii Ehrenberg, who caught protozoa and Rotaria as food,leading to a subsequent decrease in the microfauna population. Therefore, how to stabilize the microbi- al structure of mierofauna community was critical for a long-term sludge reduction in MBR. The total mass of supple- mented sludge was 126.9 g and the total reduced mass was 100.2 g in the MBR,leading to a 78.96% of reduction. Microfauna predation accounted for 73.9 % of the total reduction mass, which suggested the great importance of mi- erofauna predation for the sludge reduction in MBR.