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

Abstract

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 phosphorusladen 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 peerreviewed 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 21 st century challenges.

Selective aqueous ammonia sensors using electrochemical stripping and capacitive detection

“…We expect the relative importance of the core metrics of sensitivity, deployability, selectivity, and energy consumption to vary across these sensing applications. Similar tradeoffs have been observed using a comparative framework of value propositions for novel nutrient recovery technologies that treat and valorize wastewater 54 . For example, for monitoring of dilute TAN waters, deployability is likely to be the primary metric due to the need to detect nitrogen discharges before they induce harmful algal blooms.…”

“…Similar tradeoffs have been observed using a comparative framework of value propositions for novel nutrient recovery technologies that treat and valorize wastewater. 54 For example, for monitoring of dilute TAN waters, deployability is likely to be the primary metric due to the need to detect nitrogen discharges before they induce harmful algal blooms. In contrast, in-pipe monitoring at treatment plants is more likely to prioritize selectivity, especially when other constituents are present in high concentrations and could interfere with non-selective sensing mechanisms.…”

Potential Pitfalls in Wastewater Phosphorus Analysis and How to Avoid Them

“…From our experiences described here, particularly those during collaboration with a third-party laboratory, we now fully appreciate how critical it is for groups working on wastewater treatment technologies to report the correct P form in clear, specific units. Our concern that inconsistencies in P reporting are widespread is further supported by a recent systematic review of the literature on nutrient removal and recovery technologies by Kogler et al 30 In sorting reports for P removal efficiencies and effluent concentrations, three separate categories were required for reports of “TP = total phosphorus” and “PO 4 = phosphate,” and “P = general phosphorus species if species was not identified clearly.” 30 This review shows that there is a prevalent need to standardize quantitative performance metrics of nutrient removal and reuse technologies.…”

“… 2 , 14 , 27 , 28 Standardized P reporting is required to compare performance across different technologies and wastewater streams to accelerate technology adoption, yet a critical gap exists due to lack of a common set of metrics. 29 This knowledge gap in reporting metrics for P and its different chemical species is also highlighted in a recent systematic review of nutrient removal and recovery technologies by Kogler et al 30 In reviewing 292 articles across 46 sources, Kogler et al 30 found that removal efficiency and achievable effluent concentrations for P removal and recovery technologies are generally underreported, with only 16% of the articles reviewed giving adequate quantitative information for meaningful interpretation of technology performance.…”

Integration of silicate minerals for ammonium and phosphate removal with an on-site wastewater treatment prototype

“…Nutrient pollution is a consequence of the uncontrolled release of bioavailable ions containing nitrogen and phosphorus into the environment. The severe negative impacts of nutrient pollution are not only environmental [1,2], but also affect human health and the economy [3][4][5][6][7]. While agricultural runoff is the largest contributor to nutrient pollution, a growing global concern arises from inadequate on-site wastewater treatment discharges [8] which are likely underreported [9].…”