微生物群落结构及其调控对污泥脱水性能的影响及机制研究

Sludge conditioning is an important step during sludge treatment and resource recovery process. The key factor of sludge conditioning is the improvement of sludge dewaterability. However, the difficulty in improving sludge dewaterability and the unclear mechanism are the bottleneck problems in sludge conditioning. In this study, we will focus on the enhancement of sludge dewaterability. Through the further analysis of microbial community structure and the composition and distribution of extracellular polymeric substances in sludge, the research will identify the functional microorganisms that affect the sludge microstructure and dewaterability. At the same time, microbial community structure, characteristics of extracellular polymers and molecular functions of extracellular proteins will be used to reveal the effects of sludge microbial community structure on changes of sludge microstructure and dewaterability. In addition, the qualitative and quantitative model between sludge microbial community structure and sludge dewaterability will also be built. Based on the regulation of sludge microbial community, regulation strategies of optimizing sludge microstructure and enhancing sludge dewaterability will be established. The purpose of the research is to provide new technical pathways to improve the treatment efficiency of sludge conditioning and build solid scientific basis for the realization of safe and efficient sludge treatment process. The ideas and methods of the project have important scientific significance and engineering values.

污泥调理是污泥处理和资源化的重要步骤，其核心要素是污泥脱水能力的提高。然而，脱水性能难以提高，内部机理不明确是污泥调理过程中的瓶颈问题。本研究针对污泥脱水性能的强化问题，通过对污泥中微生物群落结构的深入分析，结合污泥中胞外聚合物的组成与分布情况，确定影响污泥微观结构和污泥脱水性能的功能微生物；并结合微生物群落结构、胞外聚合物特性以及胞外蛋白的分子功能，揭示污泥微生物群落结构对于污泥微观结构变化及脱水性能的影响及机制；构建污泥中微生物群落结构与污泥脱水性能之间的定性定量关系模型。基于污泥微生物群落的调控，建立优化污泥微观结构和强化脱水性能的调节策略。旨在为提高污泥调理工艺的处理效率提供新的技术思路和途径，为实现安全高效的污泥处理过程提供切实的科学依据。该研究的思路和技术方法具有重要的科学意义和工程应用价值。

近年来我国城市化进程加快，市政污泥产量急剧增长，污泥处理处置问题受到广泛关注。污泥调理作为污泥脱水前的预处理环节，可以有效提高污泥脱水性能，有助于实现城镇污水处理厂的污泥减量。然而目前影响污泥脱水性能的关键因素及其影响机制尚待明晰。利用污泥中微生物群落结构调控污泥胞外聚合物及污泥微观结构，可以有效提升污泥脱水性能。本研究围绕微生物群落结构及其调控的关键科学问题，开展了污泥氧化调理技术的创新研究，探究了过硫酸盐调理技术（Fe2+/HSO5-体系和Fe2+/S2O82-体系）提升不同种类来源污泥的脱水性能的影响及机制。通过分析厌氧颗粒污泥形成的典型过程，揭示了污泥中EPS蛋白质与其脱水性能表现出很强的相关性，尤其是TB-EPS中的蛋白质在氧化调理过程中减少，而在颗粒化过程中增加，这个趋势可以被认为是污泥脱水性能转变的标志。基于微生物结构变化规律，提出了利用水蚯蚓捕食过程改变污泥微生物群落结构的调控策略，调理过程可以分为两个步骤：一是水蚯蚓捕食作用破碎污泥絮体，此过程中典型丝状菌绿弯菌门丰度下降，数量减少，二是以少量的丝状菌作为骨架重新团聚污泥碎片，提升污泥脱水性能。提出了中性蛋白酶与氧化法联合调理提高污泥脱水性能的调控策略，建立了污泥脱水性能与胞外聚合物特性的深层次关联。污泥细胞活性与其脱水性能无关，但与污泥粒径和结合水含量呈正相关，与胞外有机物质含量呈负相关；EPS中多糖含量为影响污泥脱水性能的相关性最强的特性指标。本研究表明了通过投加水蚯蚓、生物酶等途径，对复杂环境下调控微生物群落结构以提高污泥脱水能力的可行性，为污泥调理工艺的可控化和定向化提供了科学依据。研究成果在Journal of Cleaner Production、Science of the Total Environment等环境领域专业期刊发表SCI论文6篇，其中第一标注4篇，第二标注2篇；申请发明专利4项，其中1项授权。