Analysis of the effects of temperature, the amount of nutrient solution and the carbon dioxide concentration on methane biofiltration

Abstract

Landfill gas emissions contribute to the greenhouse effect due to the presence of methane (CH4). CH4 emissions from old and small landfills can be reduced by using biofiltration. The objective of this study was to optimize parameters that control CH4 removal in a biofilter. Temperature is one of the important parameters as well as the amount of nutrient solution (NS) supplied. The effects of the carbon dioxide (CO 2) concentration on CH4 biofiltration were also studied. Four biofilters using an inorganic filter bed were studied under similar conditions: an inlet CH4 concentration of 7000 ppmv and an air flow rate of 0.25 m3/h. A NS was supplied daily. The temperature was varied from 4°C to 43°C. The highest performance was obtained in the range of 31-34°C with an elimination capacity (EC) of 30 g CH 4/m3/h for an inlet load (IL) of 80 g CH 4/m3/h. The effect of the amount of NS supplied to the biofilter at ambient temperature was also analyzed. The EC was 23 g CH 4/m3/h for both 101 LNS/m3V bed/d and 34 LNS/m3V bed/d, but it fell to 17 g CH4/m3/h at 17 LNS/m 3V bed/d. CO2 concentrations were varied from 650 to 18,500 ppmv and no effect was noticed on the EC which remained constant at 18 g CH4/m3/h for an inlet load of 72 g CH 4/m3/h. © 2011 WIT Press.