Microbial methane oxidation from coal mines applying a biofilter

Elimination of methane as an air contamination source was investigated using a glass column of 90 cm height and 10 cm diameter. Perlite as the packing material was inoculated with the microbial suspension resulted from washing a methane subjected soil sample. Downward flow rate of 5 L/min containing 1% (v/v) methane, as one of the potential methane pollution source seen in some industries like coal mines, was continuously injected from top of the column. The glass column was equipped with a jacket to set filter bed temperature at 30 °C. As a result, methan removal efficiency of 100% (v/v) was obtained after 47 days. After that biofilter was shut down for two weeks and restarted again to test the biofilter stability in unexpected condition and it was seen that after the shock, elimination of methane was resumed and after about two weeks maximum elimination was achieved again.