Emission of landfill gas in Qingdao, China

A study on landfill gas emission in Qingdao,China was carried out. The results showed that the generation of landfill gas with maximum methane concentration occurred several months after the refuse was disposed and the steady emission of landfill gas could remain two years.The variation of landfill gas production was associated with temperature. In June, the emission of landfill gas rose gradually from morning to evening, but in September, it rose in the morning, and then fell in the afternoon. From June to August, the emission of landfill gas showed rising trend,but it declined quite quickly from September to December. In different seasons,the outflow rate of landfill gas varied from depth to depth in the refuse site. When earth temperature was higher in summer, the emission of landfill gas did not correspond with the depth of refuse sites, but when temperature fell in winter, and the temperature became a limited factor to the gas production,the outflow of landfill gas increased with increasing in depth of refuse piling.