定向调控市政污水管道硫转化及系统优化

Hydrogen sulfide emission in municipal sewer systems has been attracted tremendous attention worldwide, which is firmly rooted in diffusion of sulfide produced in the sewage. Currently, the addition of “fluid” electron donor is mostly targeted towards area source control of sulfide in sewer, but point-source control is still lack. In this program, we propose a bio-electrochemical system which act as electron-acceptor for oxidizing sulfide to elemental sulfur consistently. The program selects the connection point of sewers which usually produce high-level sulfide as research object. Research will probe into construction of bio-electrochemical system with sewage characteristics and hydraulic parameters of sewer, as well as the principle of system operation to develop the modified bio-electrochemical system with the function of directional-control for sulfur transformation. For the system, the research is goes on to analyze and understand the sulfur transformation route and regulation, as well as the community structure and function of anodic bacteria, to clarify the synergy mechanism of microbial and electrochemical reactions, which would further guide the system optimization and operation. The program is expected to provide an adaptable technology for point-source emission of sulfide control in municipal sewer.

市政污水管道硫化氢释放问题广受关注，根源在于污水中硫化物的产生与扩散。现行投加“流动性”电子受体的方式面向于污水管道“面源”性硫化物的控制，而针对污水管道中持续产生硫化物较强的“点源”则缺乏适用性强的控制技术。因此，本项目提出一种以微生物电化学系统为电子受体将污水管道硫化物持续转化的工艺模式。以产生硫化物较强的污水管道连接处为研究对象，并结合污水管道水力水质特征，深入探讨微生物电化学系统的构建方式及运行操控要点，形成具有定向调控硫转化功能的微生物电化学系统。同时，解析硫转化途径与规律、阳极微生物群落与功能，阐述微生物-电极协同作用下的硫转化机制，指导系统优化和定向调控。为市政污水管道关键点位硫化物控制提供技术基础。

项目首先通过模拟污水管道系统构建及驯化、探讨了阳极电位、电极材料等因素对微生物阳极电化学活性的影响规律，优选出高活性微生物阳极的构建方法。对比了电极材质、构型及安放角度及排列方式优化，构建了结合污水管道特征的微生物电化学系统。结合关键操作条件如电导率等作为水质参数，调控电位、外电阻、水力停留时间（HRT）等，分析了硫去除率及转化效率、气相H2S 浓度、产电效率等关键评价指标，考察多元因子作用下的硫转化效能与生物电化学系统的内在联系，建立硫转化效率与H2S 释放浓度的关系评价。考察了生物电化学系统运行效能作用规律，提出系统不同运行工况下的调控策略。通过对解析硫转化途径与规律，阐述了微生物与电化学作用在硫转化过程中贡献及协同效应。通过对微生物群落及功能解析，解析了运行工况下的群落响应机制。阐述了微生物-电极协同作用下的硫转化机制。为市政污水管道关键点位硫化物控制提供了技术基础。