排水管道中CH_(4)、H_(2)S与N_(2)O的产生机制及其控制策略

Production mechanism and control strategy of CH_(4),H_(2)S and N_(2)O in drainage pipeline

排水管道厌氧环境会产生甲烷(CH_(4))与硫化氢(H_(2)S),而好氧及缺氧环境又会诱发氧化亚氮(N_(2)O)。污水中所含有机物(COD)、氮(N)和硫酸盐(SO_(4)^(2-))是产生这些气体的主要根源。系统综述了3种有害气体的产生机理,厘清污水中污染物、管道中微生物及管道环境对有害气体产生的影响。基于此,有针对性地提出了这几类气态污染物的控制策略。其中,对CH_(4)与H_(2)S的抑制手段集中在向管道中投加药剂以限制其产生源头,然而投加NO_(3)^(-)或NO_(2)^(-)药剂与通入氧气这两种控制手段可能会导致N_(2)O这种温室气体的大量产生。因此,应充分了解排水管道中各复杂因素之间的相互作用,以实现对有害污染气体的控制,并实现碳减排的目标。

Anaerobic environment in drainage pipeline can produce methane(CH_(4))and hydrogen sulfide(H_(2)S),while aerobic and anoxic environments will induce nitrous oxide(N_(2)O).Chemical oxygen demand(COD),nitrogen(N)and sulfates(SO^(2-)_(4))contained in wastewater are the major sources of these gases.The production mechanism of three kinds of harmful gases was systematically reviewed,and the effects of pollutants in wastewater,microorganisms in pipeline and pipeline environment on the production of harmful gases were identified.Based on this,the control strategies of these gaseous pollutants were respectively proposed.Among them,the inhibition measures of CH_(4)and H_(2)S were focused on adding chemical agents to the pipeline to limit the source control of production.However,the addition of NO^(-)_(3)/NO^(-)_(2)agents and oxygen injection might lead to large production of N_(2)O,which was a kind of greenhouse gas.Therefore,it is necessary to fully understand the interaction between the complicated controlling factors in the dainage pipeline,so as to achieve the control of harmful pollution gases and chieve the goal of carbon reduction.