REMOVAL EFFICIENCY OF HIGH-CONCENTRATION H_2S IN A PILOT-SCALE BIOTRICKLING FILTER

摘要

A pilot-scale biotrickling filter (BTF) packed with polyurethane (PU) foam was installed at one pharmaceutical factory in Zhejiang Province to study the removal of high-concentration H_2S from water treatment plant. Experiments were performed at different empty bed residence times (EBRTs), H_2S input load, ratio of liquid flow rate to gas inlet rate (L/G) and sulfate concentration in recirculating liquid to examine their effects on the performance of the BTF. The performance of this bioreactor was monitored continuously over a period of 56 days. After the start-up within 8 days, H_2S removal efficiency remained between 90% and 100% with inlet concentration fluctuating from 238 to 590 mg m~(-3)H_2S removal efficiency was consistently greater than 90%, even at a short EBRT of 9 s and inlet H_2S load higher than 187 g m~(-3)h~(-1). Profiles over the height of the reactor indicated that H_2S removal took place mostly in the first section of the column. The performance of BTF could be maintained at high and stable levels when L/G was below 0.005 and sulfate concentration down to 28 g l~(-1). The results led to the conclusion that BTF is the optimal choice for treating high-concentration H_2S.