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Abatement of dimethyl sulfide using anoxic biotrickling filter

Author:
Shihab, Mohammed Salim, Akmirza, Ilker, Mhemid, Rasha Khalid, Türker, Mustafa, Alp, Kadir
Source:
Journal of chemical technology and biotechnology 2019 v.94 no.7 pp. 2274-2283
ISSN:
0268-2575
Subject:
alpha-Proteobacteria, anaerobic conditions, bacterial communities, biodegradation, biofilters, biotransformation, denitrification, dimethyl sulfide, liquids, mass transfer, nitrates, nitrogen, oxidation, sulfates, sulfur, thermodynamics, wastes
Abstract:
BACKGROUND: This study aimed to use a lab‐scale anoxic biotrickling filter (ABTF) for the bioconversion of dimethyl sulfide (DMS) gas to produce less harmful byproducts, i.e. elemental sulfur and/or sulfate. It examined the exploitation of nitrate as an electron acceptor in the oxidation of malodorous DMS‐containing gas in combination with other parameters: gas/liquid (G/L) ratio (40, 60, 80, 100, 150), empty bed residence time (EBRT) (10, 30, 60, 90, 120 s) and inlet loading (IL) (9, 18, 48, 90 g m⁻³ h⁻¹). RESULTS: Thermodynamic analysis and half‐reactions showed that at DMS/NO₃⁻ molar yield ratios 0.75 and 0.34, elemental sulfur and sulfate were the main metabolic products respectively. Overall, 58% of the sulfur element in DMS was bioconverted to elemental sulfur. Mass balance calculations revealed high denitrification efficiency, i.e. 52.7% of inlet NO₃⁻ was converted to N₂. The optimal EBRT was found as 30 s (corresponding to removal efficiency (RE) 89%) for inlet concentration 150 mg m⁻³ and as 60 s (corresponding to RE 78%) for inlet concentration 1500 mg m⁻³. However, the maximum elimination capacity (EC) was 70.3 g m⁻³ h⁻¹ at EBRT 60 s and G/L ratio 80. The relative abundance of bacterial communities was dominated by Proteobacteria (56.1%) and Alphaproteobacteria (27.3%) at phylum and class levels respectively. CONCLUSION: The study revealed that ABTF has a reliable biodegradation capacity in DMS oxidation under anoxic conditions; however, process improvement on mass transfer enhancement for low waste gas concentrations is still required. © 2019 Society of Chemical Industry
Agid:
6471504