Wastewater treatment for carbon capture and utilization

A paradigm shift is underway in wastewater treatment as the industry heads toward ~3% of global electricity consumption and contributes ~1.6% of greenhouse gas emissions. Although incremental improvements to energy efficiency and renewable energy recovery are underway, studies considering wastewater for carbon capture and utilization are few. This Review summarizes alternative wastewater treatment pathways capable of simultaneous CO₂ capture and utilization, and demonstrates the environmental and economic benefits of microbial electrochemical and phototrophic processes. Preliminary estimates demonstrate that re-envisioning wastewater treatment may entirely offset the industry’s greenhouse gas footprint and make it a globally significant contributor of negative carbon emissions.