垃圾渗滤液原位反硝化研究

In situ Denitrification of Landfill Leachate

场外硝化–原位反硝化是垃圾填埋场氮管理的新途径.本文利用垃圾柱模拟生物反应器填埋场,研究了硝化渗滤液在填埋场内部的变迁及其对垃圾降解的影响.结果表明,硝化渗滤液回灌促进了填埋场垃圾降解,回灌的总氧化态氮(TON)被完全还原,反硝化为主要作用反应,最大TON负荷为28.6mg(N)kg(TS)-1d-1.当负荷大于11.4mg(N)kg(TS)-1d-1时,垃圾产甲烷受到抑制,抑制作用随负荷的增加而加强.在此过程中,反硝化逐渐代替产甲烷作用成为填埋场内垃圾降解的主要反应,产生气体以氮气为主,而非甲烷;硝化渗滤液与垃圾的长期作用也改变了填埋场的菌群结构.

Ex situ nitrification and sequential in situ denitrification represent a novel approach to nitrogen removal. The variation in nitrified leachate and its effects on the decomposition of municipal solid waste （MSW） were studied in a lab-scale MSW column to which nitrified leachate was recirculated. The results suggested the decomposition of MSW was accelerated, complete reduction of total oxidized nitrogen （TON） was obtained with maximum TON load of 28.6 mg（N） kg（TS）^-1 d^-1 and denitrification was the main reaction responsible. Methanogenesis inhibition was observed while TON load was over 11.4 mg（N） kg（TS）^-1 d^-1, and the inhibition was enhanced with the increase of TON load. Denitrification gradually took over methanogenesis to become the main reaction responsible for decomposition of MSW, while nitrogen gas was generated instead. Additionally, owing to long term exposure of nitrified leachate to MSW, the bacterial structure of landfill was changed. Fig 5, Tab 1, Ref 18