Energy–nutrients–water nexus: Integrated resource recovery in municipal wastewater treatment plants

• We reviewed the available resource recovery methods onsite or offsite of WWTPs.
• We synthesized the results of the life cycle studies on resource recovery.
• There is a need to evaluate resource recovery in WWTPs from life cycle perspective.
• Future research should investigate the integration of resource recovery methods.

Wastewater treatment consumes large amounts of energy and materials to comply with discharge standards. At the same time, wastewater contains resources, which can be recovered for secondary uses if treated properly. Hence, the goal of this paper is to review the available resource recovery methods onsite or offsite of municipal wastewater treatment plants. These methods are categorized into three major resource recovery approaches: onsite energy generation, nutrient recycling and water reuse. Under each approach, the review provides the advantages and disadvantages, recovery potentials and current application status of each method, as well as the synthesized results of the life cycle studies for each approach. From a comprehensive literature review, it was found that, in addition to technology improvements, there is also a need to evaluate the applications of the resource recovery methods in wastewater treatment plants from a life cycle perspective. Future research should investigate the integration of the resource recovery methods to explore the combined benefits and potential tradeoffs of these methods under different scales.