INFEWS/T3: Critical Nutrient Recovery and Reuse: Nitrogen and Phosphorus Recycling from Wastewaters as Struvite Fertilizer

该项目得到了食品、能源和水联系创新项目（infws）的支持。它解决了废水流中营养物质回收不足以及由此对水资源、能源使用和可持续粮食供应造成的压力。两种关键的营养物质，氮(N)和磷(P)，对地球上的所有生命都至关重要，包括人类、动物和植物。在世界范围内，磷的供应来自有限的磷矿储存。氮来自能源和资本密集型的工业生产氨的哈伯-博世工艺。磷和氮通过农业径流从肥料、人类和动物粪便中转移到废水中。这是养分回收和再利用而不是处理和处置的重要机会。该项目开发了创新的工程技术，以回收氮和磷营养物质作为高价值肥料鸟粪石，同时也实现了节能废水处理。该技术是在经济生命周期分析的背景下开发的。在扩大参与方面，每年举办一次由利益相关者推动的讲习班。除了降低能源使用和增加氮磷循环外，其好处还包括更清洁的水、更健康的流域和可持续的农业活动。许多本科生和研究生在跨学科的背景下接受培训。过度施肥和过量氨生产加上缺乏养分循环导致氮磷循环不平衡。这种情况导致水污染问题，在营养饱和的流域农业生存能力下降，以及过度使用能源。这个研究项目用一种电化学反应器来解决这个问题，这种反应器以鸟粪石的形式回收氮和磷，鸟粪石是一种缓释肥料。设计了一种电化学反应器，研究鸟粪石沉淀的动力学和流动动力学。该反应堆的设计是高效节能的，具有很高的现场发电潜力。开发了加速鸟粪石沉淀的关键电化学元件，包括镁合金阳极和功能肽支架。多肽功能化网状物旨在提高鸟粪石的沉淀动力学和纯度。对该工艺的能源需求进行了评估，并确定了新技术的经济成本和效益。该项目还研究了鸟粪石组成和形态对土壤组成和作物肥力的影响，研究了鸟粪石作为肥料的功效，并开发了包括系统能量平衡在内的技术生命周期评估。对于城市污水处理设施的应用，技术集成在可扩展性、水质/液体成分和成本效益方面进行了评估。

This project is supported by the Innovations at the Nexus of Food, Energy, and Water (INFEWS) Program. It addresses the lack of nutrient recycling from wastewater streams and the resulting strain on water resources, energy use, and sustainable food supply. Two key nutrients, nitrogen (N) and phosphorus (P), are critical for all life on Earth, including humans, animals, and plants. Worldwide, phosphorus supply comes from limited stores of phosphate rock. Nitrogen comes from the energy- and capital-intensive industrial Haber-Bosch process that makes ammonia. Phosphorus and nitrogen are transported from fertilizers and human and animal waste to wastewaters via agricultural run-off. There is an important opportunity for nutrient recovery and reuse rather than treatment and disposal. This project develops innovative engineering technology to recycle nitrogen and phosphorus nutrients as a high-value fertilizer, struvite, while also enabling energy-efficient wastewater treatment. The technology is developed within the context of an economic life cycle analysis. In terms of broadening participation, a stakeholder-driven workshop takes place yearly. In addition to lower energy use and increased nitrogen and phosphorus recycling, the benefits are cleaner water, healthier watersheds, and sustainable agricultural activities. Numerous undergraduate and graduate students receive training in an interdisciplinary context.Over-fertilization and excess ammonia production in addition to a lack of nutrient recycling contribute to an imbalanced N/P cycle. This situation leads to water contamination issues, decreased agricultural viability in nutrient-saturated watersheds, and excessive energy use. This research project addresses the problem with an electrochemical reactor that recovers N and P as struvite, a slow-release fertilizer. An electrochemical reactor is designed to study kinetics and flow dynamics of struvite precipitation. This reactor is designed to be energy-efficient with high potential for on-site power generation. Key electrochemical components, including the magnesium alloy anode and a functional peptide scaffold for accelerated struvite precipitation are developed. The peptide-functionalized mesh is designed to enhance struvite precipitation kinetics and purity. The energy requirements for this process are evaluated and the economic costs and benefits of the new technology are determined. The project also addresses the impact of struvite composition and morphology on soil composition and crop fertility, studies the efficacy of struvite as a fertilizer, and develops a life cycle assessment of the technology including a system energy balance. For application to municipal wastewater treatment facilities, the technology integration is evaluated in terms of scalability, water quality/liquid composition, and cost-effectiveness.