Effective removal of n-butyl methacrylate in bio-trickling filter packed with ceramsite coated with activated carbon fibers

Removal of n-butyl methacrylate from gas streams was studied in two parallel bio-trickling filters (BTFs), one packed with only ceramsite (BTFa) and the other with ceramsite coated with activated carbon fibre (BTFb). The performance of the two BTFs under various operational conditions was investigated to better understand the role of the activated carbon fibre. Results of the comparison experiments indicated that the use of activated carbon fibre could greatly shorten the start-up time of BTF. The removal efficiency of BTFb was 15.3% greater than that of BTFa under the empty bed residence time of 44s and the inlet concentration of 500 mg m−3, with the corresponding removal loading of 56.4 g m−3 h−1 and 46.5 g m−3 h−1, respectively. When the inlet loading of n-butyl methacrylate was lower than 34.0 g m−3 h−1, a complete removal of n-butyl methacrylate could be achieved in BTFb. The biomass of BTFb was 13.5 mg L−1 packing material greater than BTFa based on the dry weight, with the corresponding pressure drop 320 Pa m−1 higher than BTFa, meanwhile, the removal efficiency of BTFb remained higher all the time. The experiment showed that back washing proved a good way to reduce the pressure drop and biomass with no obvious changes in the removal efficiency.