Systematic Evaluation of Emerging Wastewater Nutrient Removal and Recovery Technologies to Inform Practice and Advance Resource Efficiency

Advancing nutrient recovery from idea to implementation requires reporting practices that facilitate comparison among diverse nutrient removal and recovery (NRR) technologies and enhance the translation of academic research to practice. We reviewed 157 technologies that treat nitrogen- and/or phosphorus-laden wastewater across several underlying mechanisms, stages of development, and scales of operation. We outline a systematic reporting and analysis framework to characterize NRR technologies using quantitative performance metrics (i.e., removal and recovery efficiency, removal and recovery rate, energy consumption, cost, greenhouse gas emissions, effluent concentration) and qualitative attributes (e.g., technology readiness level). Comparing peer-reviewed literature with practitioner needs reveals limited reporting of energy consumption and cost, indicating misalignment between research and practice. By synthesizing literature and practitioner input on anticipated benefits, barriers to adoption, and knowledge gaps, we identify opportunities for expanding benefits achieved by NRR technologies and aligning research with critical barriers. We propose a research agenda addressing the most reported gaps (e.g., underlying process mechanisms, scale-up) and emphasizing rigorous investigations of systems-level impacts and product-market fit. Results from this study will facilitate interdisciplinary research on NRR technologies, guide technology development by academics and practitioners, and accelerate implementation for resource-efficient nutrient management fit for 21st century challenges.