Alleviating sulfide toxicity using biochar during anaerobic treatment of sulfate-laden wastewater. (April 2020)

• Record Type: Journal Article
• Authors: Oliveira, Fernanda R.; Surendra, K.C.; Jaisi, Deb P.; Lu, Hui; Unal-Tosun, Gulcin; Sung, Shihwu; Khanal, Samir Kumar
• Is Part Of: Bioresource technology. Volume 301(2020)
• Publication Date: 2020-04
• Subjects: Biochar -- Anaerobic process -- Sulfide removal -- Sulfate-laden wastewater -- Sulfide toxicity; 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.2019.122711
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Biochar removed >98% of gaseous H2 S and 94% of dissolved sulfide. Maximum adsorption capacity (qm ) of biochar was 160 mg H2 S/g biochar. Oxygen functional groups played important role in sulfide adsorption onto biochar. H2 S removal by biochar alleviated sulfide toxicity and improved reactor stability. Abstract: This study examined the use of biochar to alleviate sulfide toxicity to methane producing archaea (MPA) and sulfate-reducing bacteria (SRB) during anaerobic treatment of sulfate-rich wastewater with concomitant sulfur recovery. At the sulfate concentration of 6000 mg SO4 2− /L, the dissolved sulfide (DS) of 131 mg S/L resulted in total volatile fatty acids concentration of 3500 mg/L as acetic acid (HAc) and the reactors were on the verge of failure. Biochar removed >98% of H2 S(g), 94% of DS, and 89% of unionized sulfide (H2 Saq ). 16S rRNA analysis revealed that after sulfide removal the relative abundance of MPA ( Methanobacterium and Methanosaeta ) increased from 0.7% to 3.7%, while the relative abundance of SRB ( Desulfovibrio ) decreased from 9.3% to 0.5% indicating that the reactor recovered to stable state. This study showed that biochar could effectively remove H2 S from biogas, alleviate sulfide toxicity to MPA and SRB, and promote stability of the anaerobic process.