SusChEM: Increasing Access to Sustainable Freshwater Resources with Membrane Capacitive Deionization

1605290CusickWaters咸水不像海水那样咸，在许多地区提供了一种新的有益用途的水源，成本效益高的处理方法是高度优先的。拟议的研究和教育活动将通过为电容式海水淡化技术建立一个综合的多尺度模型和实验框架，促进微咸水(咸水)地下水和再生废水淡化的可持续性。研究将利用可再生碳资源追求经济上可行的海水淡化战略，并将重点放在克服限制我们设计能效和成本效益高的膜电容去离子系统能力的知识差距上。将利用这一框架向本科生和高中生传授缺水、可持续水管理和通过海水淡化生产淡水的知识。减少淡水生产的能源强度，同时增加再生水和盐碱源的水回收，将是将经济成本和环境影响降至最低的关键。这项工作的总体目标是，通过解决现有的对苦咸水和再生水淡化的经济和能源障碍，增加缺水地区获得可再生淡水资源的机会。通过将淡水和盐水生产分别与电容器电极充电和放电相结合，膜电容去离子系统能够在接近海水淡化的热力学极限时去除水中的离子，所需的能量比反渗透要少得多。由于反渗透的能源、维护和盐水处理成本，目前在大多数地区，从低盐度来源(即微咸水和再生废水)生产饮用水在经济上是不可行的。这项研究试图解决目前限制膜电容去离子的关键障碍，通过在一个集成的建模和量化的可持续设计框架内开发新的电极几何形状和操作方案，将微结构组成、反应堆设计和操作决策与处理效率、淡水生产成本和环境可持续性的预测联系起来，从而成为反渗透的潜在低成本和可持续替代方案。这个假设是，基于电容器的去离子可以使从苦咸水和再生水中生产淡水具有能源效率和成本效益。这项拟议工作的目标是：i)通过集成的建模和实验来揭示膜电容去离子系统中的电化学能量损失机制；ii)开发针对主要能量损失机制的新型高性能电极形态；iii)开发经校准以达到能量和水回收技术极限的膜电容去离子过程模型；以及iv)通过将该过程模型集成到可持续设计框架中，在不确定的情况下集成环境、经济和性能指标，从而为膜电容去离子系统的发展开辟一条前进的道路。

1605290CusickWaters that are salty, not to the extent that sea water is, present a new source of water for beneficial use in many areas and cost efficient methods for treating them are a high priority. The proposed research and educational activities will advance the sustainability of brackish (salty) groundwater and reclaimed wastewater desalination by establishing an integrated multi-scale modeling and experimental framework for capacitive desalination technologies. Research will pursue financially viable desalination strategies with renewable carbon resources and will focus on overcoming knowledge gaps that limit our ability to design energy efficient and cost effective membrane capacitive deionization systems. This framework will be leveraged to teach undergraduates and high school students about water scarcity, sustainable water management and freshwater production through desalination. Reducing the energy intensity of freshwater production, while increasing water recovery, from reclaimed and saline sources will be critical to minimizing economic costs and environmental impacts. The overall goal of this work is to increase access to renewable freshwater resources in water stressed regions by addressing existing economic and energetic barriers to brackish and reclaimed water desalination. By coupling freshwater and brine production to capacitor electrode charging and discharging respectively, membrane capacitive deionization systems have the potential to remove ions from water near the thermodynamic limit of desalination, requiring far less energy than reverse osmosis. Producing potable water from low salinity sources (i.e., brackish water and reclaimed wastewater) is currently economically infeasible in most areas due to energy, maintenance and brine disposal costs of reverse osmosis. This research seeks to address critical barriers currently limiting membrane capacitive deionization, a potentially low cost and sustainable alternative to reverse osmosis, by developing novel electrode geometries and operating schemes within an integrated modeling and quantitative sustainable design framework that links microstructure composition, reactor design and operation decisions to predictions of treatment efficacy, freshwater production costs and environmental sustainability. The hypothesis is that capacitor-based deionization may enable energy efficient and cost effective production of freshwater from brackish and reclaimed water. The objectives of this proposed work are: i) to uncover mechanisms of electrochemical energy loss in membrane capacitive deionization systems through integrated modeling and experimentation; ii) to develop novel high performance electrode morphologies that address major energy loss mechanisms; iii) to develop a membrane capacitive deionization process model calibrated to the limits of technology for energy and water recovery; and, iv) to establish a path forward for membrane capacitive deionization development by integrating the process model into a quantitative sustainable design framework that integrates environmental, economic, and performance metrics under uncertainty.