Anaerobic/aerobic/coagulation treatment of leachate from a municipal solid wastes incineration plant

Environ Technol. 2012 Apr-May;33(7-9):927-35. doi: 10.1080/09593330.2011.602435.

Abstract

Municipal solid wastes (MSW) in China contain a large fraction of food waste and have high moisture content. MSW is usually held in waste pits for a few days to reduce moisture content before combustion in an incineration plant. In this study, leachate from the Tongxing MSW incineration plant was characterized and a combined anaerobic-aerobic-coagulation system was proposed and investigated. Optimal operation conditions for the processes in the proposed system were identified. The performance of the treatment process was assessed by monitoring the removal of organic matter (COD) and ammonia nitrogen (NH3-N). The results showed that the optimal volume ratio of leachate and sewage was 1:6. During the initial anaerobic treatment, 62.1% COD and 49.5% ammonia were removed (optimal reaction time: 20 h, hydraulic retention time: 4 d). During the subsequent aerobic treatment (optimal aeration time of 14 h, dissolved oxygen of4 mg/L), up to 94.0% COD and 89.4% ammonia could be removed. The coagulation process served as a polishing step. The optimal dose of Fe2(SO4)3 was 600 mg/L at a pH of 5.0. The COD and ammonia concentrations in the final effluent after the combined treatment were 138 mg/L and 22 mg/L, respectively, which meet the Chinese integrated wastewater discharge standards.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aerobiosis
  • Ammonia / isolation & purification*
  • Anaerobiosis
  • Bioreactors
  • Incineration
  • Waste Management / methods*
  • Water Pollutants, Chemical / analysis

Substances

  • Water Pollutants, Chemical
  • Ammonia