Enhanced anaerobic treatment of sulfate-rich wastewater by electrical voltage application. (February 2023)

• Record Type: Journal Article
• Authors: Prakash, Om; Mostafa, Alsayed; Im, Seongwon; Song, Young-Chae; Kang, Seoktae; Kim, Dong-Hoon
• Is Part Of: Bioresource technology. Volume 369(2023)
• Publication Date: 2023-02
• Subjects: Sulfidogenesis -- Gene analysis -- Dissimilatory sulfate reduction -- Ni/Fe hydrogenase -- Direct interspecies electron transfer (DIET; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2022.128430
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: "Created with BioRender.com". Highlights: Electrical voltage (EV) enhanced CH4 production by 30 % and sulfate removal by 40 %. High energy recovery for EV-applied reactor supports the practical applicability. The abundance of sulfate-reducing bacteria was increased by 1.5 times in EVR . The abundance of Dsr and hydrogenase genes was >50 % higher in EV-applied. F-type ATPase gene expression was increased by (x3) in the archaeal community. Abstract: Treatment of sulfate-rich wastewater with high methane recovery is a major concern due to sulfide inhibition. Here, an electrical voltage (EV) aims to enhance methanogenesis and sulfidogenesis to treat sulfate-rich wastewater. Two (control and EV-applied) reactors were operated with a gradual decrease in chemical oxygen demand (COD)/SO4 2− ratios (CSR). EV-applied reactor (EVR) demonstrated an increase of ∼30 % in methane production and ∼40 % in sulfate removal, compared to the control till CSR of 2.0. At CSR 1.0, the control failed, while EVR still exhibited a stable performance of 50 % COD-methane recovery. Microbial community results showed that the relative abundance of sulfate-reducing bacteria in EVR was 1.5 times higher than the control. Furthermore, higher relative abundance of dissimilatory sulfate reductase (>50 %) and Ni/Fe hydrogenase (x15) genes demonstrated an improved tolerance against H2 S toxicity. This study highlights the importance of EV application by minimizing the byproduct inhibition in sulfate-rich wastewater.