Removal of high concentrated ammonia nitrogen from landfill leachate by landfilled waste layer

Article type: Research Article

Authors: GUO, Hui-dong | HE, Pin-jing | SHAO, Li-ming | LI, Guo-jian

Affiliations: State Key Laboratory of Pollution Control & Reclamation, Tongji University, Shanghai 200092, China

Note: [] Corresponding author. E-mail: [email protected]

Abstract: The landfill of municipal solid waste (MSW) could be regarded as denitrification reactor and used in ammonia nitrogen biological removal process. In this research, the process was applied to municipal solid waste (MSW) collected in Shanghai, China, which was characterized with high food waste content. The NH_4^+ removal efficiency in the system of SBR nitrifying reactor followed by fresh and matured landfilled waste layer in series was studied. In the nitrifying reactor, above 90% of NH_4^+ in leachate was oxidized to NO_2^- and NO_3^-. Then high concentrated NO_2^- and NO_3^- was removed in the way of denitrification process in fresh landfilled waste layer. At the same time, degradation of fresh landfilled waste was accelerated. Up to the day 120, 136.5 gC/(kg dry waste) and 17.9 gN/(kg dry waste) were produced from waste layer. It accounted for 50.15% and 86.89% of the total carbon and nitrogen content of preliminary fresh waste, which was 4.42 times and 5.17 times higher than that of reference column respectively. After filtering through matured landfilled waste, BOD5 concentration in leachate dropped to below 100 mg/L, which would not affect following nitrification adversely. Because the matured landfilled waste acted as a well methanogenic reactor, 23% of carbon produced accumulatively from fresh landfilled waste degradation was converted into CH_4.

Keywords: landfill leachate recirculation, ammonia biological removal, fresh landfilled waste, matured landfilled waste

Journal: Journal of Environmental Sciences, vol. 16, no. 5, pp. 802-807, 2004