Impact of nutrients supply and pH changes on the elimination of hydrogen sulfide, dimethyl disulfide and ethanethiol by biofiltration

Abstract

h i g h l i g h t sThe treatment of sulfur odorous compounds in mixture, H 2 S, DMDS and EtSH by biofiltration was examined. Removal efficiencies of biofilters packed with pine bark and composted wood mulch were compared. The degradation of the three compounds decreased as follows: H 2 S > DMDS > EtSH. Contrarily to EtSH and DMDS, H 2 S removal was not affected by the lack of nutrients in the biofilter. pH decrease caused by H 2 SO 4 accumulation impacted EtSH and DMDS degradation contrarily to H 2 S removal. a b s t r a c tThe treatment of sulfur odorous compounds in mixture, hydrogen sulfide (H 2 S), dimethyl disulfide (DMDS) and ethanethiol (EtSH), by biofiltration was examined. A significant effort was focused on the impact of nutrients supply, without forgetting the effect of other parameters such as the pH, on the process performances. Removal efficiencies of three biofilters packed with pine bark and composted wood mulch and sprinkled by different nutritive solutions were compared.Owing to the biodegradability of H 2 S, its removal was not affected by the lack of nutrients in the biofilter. However, for EtSH and DMDS, considered as more recalcitrant, the influence of nutrients on biodegradation was clearly observed; it was enhanced when the supplementation in the watering solution was increased. Furthermore, EtSH removal yield increased from 80% in the absence of supplementation to an almost total removal in the presence of nutrients in the watering solution. The degradation of the three compounds decreased as follows: H 2 S > DMDS > EtSH. The impact of the pH of the packing materials was also underlined. The decrease in pH caused by the accumulation of sulfuric acid in the packing material, the most abundant product of the biological oxidation of sulfur compounds, led to a reduction of the elimination efficiencies of EtSH and DMDS; while the microorganisms involved in H 2 S degradation appeared active in a large pH range, from less than 3 to close to 9.

Removal of hydrogen sulfide in air using cellular concrete waste: Biotic and abiotic filtrations

“…The objective is clearly to find a material that could be used as a H 2 S scavenger to treat high H 2 S concentration in air as well as in biogas. In a first approach, the H 2 S concentrations considered are ranged from 50 to 500 ppmv in order to compare the results obtained with data reported in the literature [17,19,[25][26][27]. One such new material is cellular concrete waste.…”

“…Organic media, such as compost, peat, and pine bark, are widely used for H 2 S treatment because they contain nutrients [17][18][19][20]. Inorganic media, such as expanded schist, pozzolan and lava, are also used due to their interesting mechanical behavior [21][22][23][24].…”

Proposed mechanisms of toluene removal by vermicompost and earthworms Eisenia fetida

“…The gaseous effluent passes through a fixed film bioreactor. Pollutants contained within it are transferred to the biofilm present in the packing material and oxidized or converted into biomass by microorganisms [6][7][8]. The degradation of the pollutants leads to the production of metabolic by-products, carbon dioxide and water.…”

“…However, they have poor mechanical properties and are subject to settling and the generation of preferential pathways [16]. For these various reasons, a mixture of organic and inorganic material is often employed [8,17]. The main role of the inorganic material (pozzolan, porous pebbles, activated carbon, etc.)…”

Biofilms formed within the acidic and the neutral biotrickling filters for treating H2S-containing waste gases

“…2,13,14 Although previous reports have evaluated the inuences of packing materials, pH, inlet loading rates and dissolved oxygen on the removal performance of bioreactor, the detailed mechanism concerning the formation of biolms in acidic BTF as well as their associations with various environmental parameters and microbial species remain largely unclear. [15][16][17] Inside the biolms, microbial cells are kept together by extracellular polymeric substances (EPS) in close proximity.…”