Removal of trimethylamine in a biofilter packed with waste tire chips

Trimethylamine (TMA) is a product of decomposition of living things and it has a strong odor. A biofilter (BF) packed with waste tire chip for reuse as a new media, and inoculated with activated sludge was tested for TMA removal. Gas-phase 0.024-0.036 g TMA m^-3 was removed by up to 95% with empty bed residence time (EBRT) of 30 and 20 s, but the removal efficiency (RE) reduced to 80% at an EBRT of 15 s. For concentrations varying between 0.012 and 0.024 g TMA m^-3 at an EBRT of 20 s, 95% of TMA was removed, which then decreased to as low as 80% for concentrations varying between 0.049 and 0.056 g m^-3. As a result, the RE of TMA in the BF was found to be a strong function of both concentration and EBRT. The critical elimination capacity (EC) point of TMA was inlet loading rate (ILR) of 5 g m^-3 h^-1 and the maximum EC was determined to be 14 g m^-3 h^-1 at an ILR of 23 g m^-3 h^-1. It was concluded that tire chips can be effectively used as a biofilm support material in BFs where the REs for TMA can be most greatly achieved at lower loading rate during relatively longer reaction time period.