Microaeration Process Design, Control, and Monitoring for Biogas Desulfurization in Anaerobic Digestion

ABSTRACT Microaeration has emerged as an effective in situ approach for biogas desulfurization in anaerobic digestion (AD). This review critically assessed the effects of key microaeration parameters, including injection locations (liquid vs. gas phase), oxygen source (air vs. pure oxygen), dosage, and process control and monitoring techniques. This review identified several challenges to its large‐scale implementation, including a lack of optimal process design and limited economic analysis. Other key challenges include balancing oxygen injections to prevent methanogenic inhibition and organic co‐oxidation, managing biogas dilution by residual oxygen and nitrogen, and the operational complexities associated with elemental sulfur removal. Proportional–integral–derivative (PID)‐controlled systems that utilize oxidation‐reduction potential and H 2 S feedback have strong potential for process automation; however, real‐time monitoring tools and process control strategies are still in early stages of development. Moreover, its impact on hydrolysis, volatile solids reduction, and methane yield has been inconsistent. Addressing these gaps is crucial for the wide‐scale application in AD facilities.