Pilot-scale study using biotrickling filter to remove H2S from sewage lift station: Experiment and CFD simulation

Abstract

In this study, a pilot-scale biotrickling filter (BTF) was developed to remove poisonous gas contaminated by hydrogen sulfide (H2S) from a sewage lift station. The BTF provided a smooth start-up with an increase in the inlet H2S concentration and delivered a stable operation for more than 300 days. The biomass concentration and microbial community structures were analyzed to determine the biodegradation kinetics, and some key operating variables, the inlet H2S concentration and empty bed retention time (EBRT), were investigated to explore the deodorization performance of the pilot-scale BTF. When the EBRT was 10.9–28.9 s and the inlet H2S concentration was 5–20 ppmv, an H2S removal efficiency of no less than 99% was observed. The elimination capacity (EC) reached 6.58 g H2S/m3/h (removal efficiency of 99.8%) for an EBRT of 10.9 s. In addition, a computational fluid dynamics (CFD) model was integrated with a biodegradation kinetic model and a porous medium model to simulate the deodorization performance of the pilot-scale BTF. Under different operating conditions, the simulated results agreed well with experimental data for H2S concentration profiles and the pressure drop (R2>0.985), which indicates that the established CFD model can be used as a reference for optimizing the design and scale-up of the BTF.