| Large scale installations were established according to the traditional anaerobic landfilling theory and semi-aerobic landfilling theory. The concentration of CH4,CO2,O2 and temperature in the structures had been detected regularly for about 1.5 years.The results showed that, the anaerobic atmosphere was formed after 21 weeks in anaerobic landfill structure, the methane concentration was 38.4%. The anaerobic-aerobic atmosphere was formed after 17 weeks in the semi-aerobic landfill structure, the space level variation of methane concentrations were declined with the sequence of under-layer, middle-layer and upper-layer, the methane concentrations were 33.1%, 15% and 3.1% respectively. The oxygen concentrations in semi-aerobic landfill were declined with the sequence of upper-layer, middle-layer and under-layer, the concentrations of oxygen were 14.6%, 1.8% and 0.5% respectively.Methane production in semi-aerobic landfilling structure was about 1/2 of that in anaerobic landfilling structure. It was effective to reduce the CH4 production in semi-aerobic landfilling treatment compared to the anaerobic landfilling treatment.The space level variation of temperature was declined according to the sequence of up level, middle level and under level. The temperature rose with the increasing of the concentration of oxygen. Methane production was restrained in the upperlayer and middlelayer with a high temperature above 66℃. Leachate recirculation can enhance the temperature of semi-aerobic landfill distinctly, the temperature was enhanced about 6℃than the water recirculation landfill.The spatial variability of temperature in semi-aerobic landfilling structure were studied by semivariogram, it was indicated that the semivariogram function of temperature was well modeled by the linear with sill model. The correlation range of profile was 3.5m and the sill value was 83.6. The unmeasured temperature values were interpolated with the KRIGING method. The temperature isoline showed that the high temperature region located at 3-5.5m on vertical direction of the middle part, the low temperature area laid in the two sides of the landfill structure and substrate 0-1m. The weighted average temperature of profile was 59.8℃. |
