Utilizing an alternating current redox environment for efficient sulfur-rich anaerobic digestion effluent and recovery of elemental sulfur

This study proposes to couple anaerobic digestion technology with bioelectrochemical technology. Firstly, the anaerobic digestion process is used to treat organic wastewater containing sulfates while recovering the methane produced. Then, the sulfide containing and various VFAs substrates in the effluent are introduced into the bioelectrochemical system. Microbial and anodic oxidation are used to remove sulfides while also recovering S0 as an energy source. The electrons generated by oxidation can be used as electron donors for the cathode through external circuits to provide electrons for the anaerobic digestion system, increasing the efficiency of sulfate reduction and methane production. This is expected to achieve electronic self balance within the system and improve the application of bioelectrochemical systems in treating sulfur-containing organic wastewater. The new coupled process is expected to have higher economic value and application prospects.