Study On MSW Landfill Gas Generation Process And Its Production Modeling

Landfill, the predominant method of municipal solid waste (MSW) treatment nowadays, will emit landfill gas (LFG) to environment, which are mainly made up of methane and carbon dioxide and will be great harmful to environment and human beings. Landfill gas, however, is a kind of renewable energy. Therefore, it is imperative to recover LFG. In order to recover LFG, it is necessary to research the production and generation rate of LFG. The process of LFG generation is very complicated, which is affected by many factors. Although some landfill gas models have been developed at abroad, these models can't be directly used in China because of great difference in characters between domestic and alien MSW. Domestic study, however, can't meet the demand of recovery. Consequently, it is prerequisite to establish LFG model that is adapt to the characters of domestic MSW for recycle LFG.The essence of anaerobic decomposition and gas generation kinetics were analyzed and the equations of methane and carbon dioxide generation rate were brought forward in this paper though investigate the related literatures of landfill gas model at home and abroad and analyze factors that affect anaerobic decomposition of MSW. Furthermore, the data of gas production and generation rate were acquired through experiment and landfill gas models fit for domestic MSW were advanced in this paper.The main works and conclusions in this paper are as follows,①Temperature and sewage sludge, the mainly two factors that affect decomposition and gas production of MSW, were compared in this paper. The results show that:a)At the range of 20℃~40℃, temperature increase can not only enhance LFG production but accelerate the speed of gas generation. b)Adding sewage sludge in lysimeter can not only markedly increase LFG production and generation rate, but also extremely enhance methane content.c)If water content of MSW reaches or approaches field capacity, leachate produced from MSW itself recycle can treat itself, but can have little effect on gas production and generation rate.②The model of actual production of MSW in China was put forward. ③On the basis of experiments, The LFG models fit for characters of Chongqing were brought forward, and actual values, predicted values and Scholl Canyon model values of gas generation rate were compared in this paper. The results show that the models are reasonable and credible. Moreover, The gas production and generation rate of one landfill site of Chongqing were computed with these models.