Electrochemical Valorization of Biosolids: A Comprehensive Review of Resource Recovery and High-Value Product Generation

Sarath Poda*, Gerardine G Botte

The rapid growth of municipal and industrial wastewater treatment has led to an unprecedented accumulation of biosolids, traditionally managed through land application, incineration, or disposal pathways that often undervalue their embedded chemical and energetic potential. In the context of the circular economy, biosolids should no longer be viewed as residual waste streams but as reservoirs of recoverable carbon, nitrogen, phosphorus, and energy. Electrochemical sludge valorization has recently emerged as a transformative approach that leverages controlled redox reactions to convert complex organic and nutrient-rich matrices into hydrogen, fertilizers, and other value-added products under relatively mild and modular operating conditions. This review critically examines the integration of electrochemistry, microbiology, and process engineering in advancing biosolids valorization technologies. Key pathways discussed include electrochemical ammonia recovery and electrolysis for hydrogen generation, electro-oxidation of refractory organics, electro-assisted phosphorus precipitation, and bio-electrochemical systems such as microbial electrolysis cells. Particular emphasis is placed on reaction mechanisms, electrode materials, mass transfer limitations, energy efficiency, and reactor design considerations that govern process performance. Comparative analysis with conventional biological and thermal sludge treatment technologies highlights both the advantages and current limitations of electrochemical approaches. Furthermore, this review evaluates techno-economic feasibility, scalability challenges, and life-cycle implications, identifying critical research gaps that must be addressed to transition from laboratory-scale demonstrations to full-scale implementation. By bridging wastewater treatment, electrochemical engineering, and resource recovery, electrochemical sludge valorization represents a promising platform for sustainable materials and energy production, aligning environmental stewardship with chemical process innovation.

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Published on: Jun 24, 2026 Pages: 1-24

Full Text PDF Full Text HTML DOI: 10.17352/aest.000092
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