Effects of Nitrate on Anoxic /Anaerobic Oxidation of Methane in the Aged Refuse

This work investigated the effects of nitrate on anoxic /anaerobic methane oxidation in the aged refuse landfilled 10-12 years by full-factor experiments. The results showed that under anoxic / anaerobic condition,nitrate could promote the removal of methane in the aged refuse. The contents of CH4and NO-3-N had significant influences on the removal of CH4and the generation of N2,and there were significant interactions as well( P 0. 05). The increasing initial CH4content evidently enhanced the removal of CH4and the production of N2. Furthermore,the addition of NO-3-N obviously improved the de-nitrification process. The results suggested that nitrate reduction could be coupled to anoxic / anaerobic oxidation of methane in the aged refuse. In the experimental condition,the effort of coupling was most effective when the concentrations of CH4and nitrate were 30% and 110 mg·kg- 1,respectively.