Advancements in anaerobic membrane bioreactor (AnMBR) technology have opened up exciting possibilities for sustaining precise water quality control in wastewater treatment and reuse. This approach not only presents an opportunity for energy generation and recovery but also produces an effluent that can serve as a valuable nutrient source for crop cultivation in hydroponic controlled environment agriculture (CEA). In this perspective article, we undertake a comparative analysis of two approaches to municipal wastewater utilization in agriculture. The conventional method, rooted in established practices of conventional activated sludge (CAS) wastewater treatment for soil/land-based agriculture, is contrasted with a new paradigm that integrates AnMBR technology with hydroponic (soilless) CEA. This work encompasses various facets, including wastewater treatment efficiency, effluent quality, resource recovery, and sustainability metrics. By juxtaposing the established methodologies with this emerging synergistic model, this work aims to shed light on the transformative potential of the integration of AnMBR and hydroponic-CEA for enhanced agricultural sustainability and resource utilization. 
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                            Nutrient recovery from treated wastewater by a hybrid electrochemical sequence integrating bipolar membrane electrodialysis and membrane capacitive deionization
                        
                    
    
            The growing needs for sustainable nutrient management and pollution control have motivated the development of novel technologies for nutrient recovery from wastewater. However, most of the existing technologies require extensive use of chemicals and intensive consumption of energy to achieve substantial recovery of nutrients. Herein, we present a hybrid electrochemical sequence integrating two relatively novel electrochemical processes, bipolar membrane electrodialysis (BMED) and membrane capacitive deionization (MCDI), for simultaneous removal of phosphorus and nitrogen. Specifically, the BMED process is employed to alkalify the wastewater to facilitate struvite precipitation and the MCDI process is used to further reduce the ammonia concentration in the effluent and concentrate the excess ammonia to a small stream. The electrochemical sequence is demonstrated to remove ∼89% of phosphorus and ∼77% of ammonia, recovering ∼81% of wastewater as a high-quality effluent that can be discharged or reused. This electrochemical treatment train minimizes chemical use and has competitive energy consumption as compared to electrochemical processes for nutrient recovery from wastewater. 
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                            - Award ID(s):
- 1739884
- PAR ID:
- 10188369
- Date Published:
- Journal Name:
- Environmental Science: Water Research & Technology
- Volume:
- 6
- Issue:
- 2
- ISSN:
- 2053-1400
- Page Range / eLocation ID:
- 383 to 391
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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