城镇污水管道系统甲烷产排特性及发生机制

城镇污水管道系统中产生的甲烷是城镇碳排放的主要来源之一,深入研究污水管道系统中甲烷的产排特性及发生机制对城镇污水提质增效和碳减排至关重要。综述了城镇污水管道系统中甲烷产排的研究现状,分析了甲烷产排的主要影响因素及发生机制,归纳了污水管道系统中甲烷产排的模拟评估方法。结果表明:污水管道内部环境、水质特性、水力条件等是影响甲烷产排的主要因素;生物膜-管道沉积物-污水多相界面的生化反应和传质过程是造成甲烷产排特性差异的关键原因;耦合管道水动力、颗粒物沉降过程、生化反应动力学、构建污水管道系统甲烷产排模型并应用于污水管道系统的甲烷排放测评与控制,是今后研究的发展方向。

EMISSION CHARACTERISTICS AND MECHANISMS OF METHANE IN MUNICIPAL SEWER SYSTEMS

Methane (CH₄) generated from municipal sewer systems is one of the major sources of urban carbon emissions.Understanding of emission characteristics and mechanisms of CH₄ is essential to reducing carbon emission and improving wastewater treatment systems.Therefore,this paper reviews the current research on the CH₄ emission in municipal sewer systems,analyzes the main factors and emission mechanisms related to the CH₄ emission.The mathematical modeling methods for evaluating CH₄ emission are discussed as well.The results show that internal environment of sewers,water quality and hydrodynamic conditions greatly affect the CH₄ emission.The biochemical reactions and mass transfer on the multiphase interface of biofilm-pipe sediment-wastewater cause differences in the emission characteristics of CH₄.The mathematical models for the CH₄ emission from sewer systems should be established by coupling pipeline hydrodynamics,particular sedimentation,and biochemical reaction kinetics.The evaluation and control of CH₄ emission from sewer systems could be supported by these mathematical models in the future.