Research On Anaerobic Oxidation Of Methane In Manganese Ore Constructed Wetlands And Manganese Valence Change

In the case of global warming is a hot research topic, the related researches of methane generation and emission have caused wide public concern. Now the methane level decreased by 10% to 60%.Therefore anaerobic methane oxidation can effectively reduce methane emissions, slow global warming caused by greenhouse effect.Wetland methane oxidation is an important part of the wetland methane emissions control, has had a huge impact to eventually reduce wetland methane emissions.In this research, the common natural manganese ore and gravel work as wetland packing matrix, adopt the contrast test, under anaerobic conditions, to carry out the indoor experiment study for one and a half years. Observing different reactor's methane production situations, exploring the wetland methane generation and the effect of anaerobic oxidation of methane?the main mechanism of manganese ore wetland methane anaerobic oxidation and manganese valence changes and circulation, etc..The key results and conclusions were as follows:?1?Through the comparative analysis, we found in the manganese ore wetland, removal efficiency for sewage COD and TP is good, and both the removal rates are over 90%.?2?Through Comparative analysis manganese ore with gravel wetlands' CH₄ content in the gas sample, manganese ore artificial wetland basically cannot detected the existence of CH₄, gravel group detected in CH₄, it means in manganese ore wetland plant, the anaerobic methane oxidation?AOM? happened, manganese ore artificial wetland have obvious effect in removal of CH₄.?3?By comparing the manganese ore and gravel wetland in pH, concentration of Mn²⁺ and methane discharge.It's deduced that CH₄ is oxidized by MnO₂ in the manganese ore wetland.Manganese reduction bacteria was observed in the subsequent experiments, the increasement of bivalent manganese in manganese ore wetland is proved.?4?In correlation analysis of the concentration of Mn²⁺ in manganese ore wetland and the CH₄ in gravel wetland, we found that the two have great relevance.And in manganese ore wetland, the consumption of CH₄ by MnO₂ oxidation is far less than CH₄ generated in ordinary gravel, the reason may be that in the manganese ore wetland, manganese reduction bacteria and methane-producing bacteria have a competitive relationship, inhibits the generation of methane.?5? At the bottom of the Device,in completely anaerobic environment, MnO₂ is preferably reductied into Mn²⁺; After one cycle, the concentration of Mn²⁺ of four sample points is less than the Mn²⁺ concentrations of samples cultivated for two days;Considering the factors of measurement error,we also can conclude the possibility of Mn²⁺ was oxidized into MnO₂.?6?Through the comparison and analysis, found that the manganese content of the samples in the wetland after trainning seven months in the root part and at the bottom of the manganese ore wetland and fresh manganese ore, they are no different.