Simultaneous hydrogen sulphide and ammonia removal in a biotrickling filter: Crossed inhibitory effects among selected pollutants and microbial community change

A coal slag-packed biotrickling filter inoculated with autotrophic sulphide oxidizing and ammonia oxidizing bacteria was successfully operated for co-treating hydrogen sulphide (H₂S) and ammonia (NH₃). Excellent removal efficiencies of H₂S (98.5%) and NH₃ (99.9%) were obtained at loadings of up to 120 g H₂S m⁻³ h⁻¹ and 80 gNH₃ m⁻³ h⁻¹, respectively. The inhibitory effects of selected pollutants and metabolic products on the treatment performance were evaluated through mass balance and bacterial community analyses. The presence of NH₃ significantly affected the composition of metabolic products of sulphide oxidation. Elemental sulphur was the dominant metabolite that ranged from 35% to 65%, whereas the amount of sulphite and thiosulphate generally increased up to 20%. However, a similar trend in the distribution of by-products to the results of nitrogen mass balance from sole NH₃ removal was observed. The predominant bacteria were also changed with different loading ratios (H₂S: NH₃). Copyright © 2015 Published by Elsevier B.V.