Methane and sulfide mitigation in sewers through bioelectrochemical systems

Summary

Sewer systems are the integral part of urban infrastructure, responsible for collecting and conveying wastewater to treatment facilities. During this process, significant amounts of methane and hydrogen sulfide are produced, with methane being a potent greenhouse gas and hydrogen sulfide causing corrosion in sewer pipes. Effective control strategies are urgently needed. Adding thermodynamically favorable electron acceptors (e.g., nitrate) has been recognized as an effective method for controlling sulfide and methane in sewer systems. However, the sustainability of this strategy is limited due to the need for repetitive chemical additions. Bioelectrochemical systems (BES) offer a promising alternative by allowing the sustainable introduction of solid electron acceptors (i.e., anodes) into sewer systems, without the need for repeated addition of chemicals. This PhD thesis explores the feasibility of using BES to mitigate methane and hydrogen sulfide production in sewer systems by studying the competition among electroactive bacteria, sulfate-reducing bacteria, and methanogenic archaea.