Development of cost-effective and long-lasting integrated technology for H2S control from sludge in wastewater treatment plants. Issue 2 (12th December 2022)

• Record Type: Journal Article
• Authors: Hao, Tianwei; Zeng, Jiajia; Pan, Jianyu; Huang, Wenzhuo; Kong, Zhe; Sun, Jianliang
• Is Part Of: Environmental science. Volume 9:Issue 2(2023)
• Page Start: 433
• Page End: 441
• Publication Date: 2022-12-12
• Subjects: Water-supply -- Periodicals; Water security -- Periodicals; Water resources development -- Periodicals; Water chemistry -- Periodicals; 553.705
• DOI: 10.1039/d2ew00496h
• Languages: English
• ISSNs: 2053-1400

Abstract

Abstract : Integrated aeration-oxidant and glutaraldehyde-oxidant were cost-effective. Integrated glutaraldehyde-oxidant and oxidant-Fe2 O3 had a long-lasting performance. Efficient H2 S control was achieved via synergistic pathways. Abstract : Hydrogen sulfide (H2 S) production and emissions from sulfate-reducing bacteria (SRB) during wastewater and sludge (primary sludge and excess activated sludge) treatment and disposal are major concerns due to odor nuisance, corrosion, and health risks associated with H2 S. The widely used chemical dosing approach requires high amounts of chemicals, resulting in high treatment costs. To develop cost-effective and long-lasting technologies for the H2 S control from the sludge, this study proposed integrated methods, including oxidant–glutaraldehyde dosing, aeration–oxidant dosing, and oxidant–iron oxide (Fe2 O3 ) dosing. Two oxidants (hydrogen peroxide and sodium chlorite) and one biocide (glutaraldehyde) were selected. All the integrated methods yielded good performances in the H2 S control, from the sludge, due to the synergistic pathways involved, namely, sulfide oxidation by oxidants and Fe2 O3, and the inhibition of the SRB activity by glutaraldehyde. The optimal removal efficiencies of H2 S in the gas phase and dissolved sulfide in the sludge phase were up to 99.8% and 99%, respectively, within 4 h. Moreover, the integration of oxidants with glutaraldehyde and Fe2 O3 decreased the hydrogen sulfide release by 66–93%, in prolonged periods of 24–48 h. The integrated oxidant–glutaraldehyde dosing and aeration–oxidant dosing, with treatment costs between 0.5–1.57 USD per m 3 sludge, were more cost-effective than the integrated dosing of Fe2 O3 (12.22–13.68 USD per m 3 sludge), as well as the case of dosing a single oxidant (0.53–2.35 USD per m 3 sludge). The findings demonstrated that the integrated oxidant–glutaraldehyde and aeration–oxidant dosing could be cost-effective and long-lasting alternatives to the conventional chemical dosings for H2 S control from sludge, oil wells, and reservoirs. This shows the potential industrial application of this work.