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

[1605290]含盐量不像海水那么高的cusicks水域，为许多地区提供了有益利用的新水源，而低成本的处理方法是当务之急。拟议的研究和教育活动将通过建立电容式海水淡化技术的综合多尺度建模和实验框架，促进半咸水（含盐）地下水和再生废水的可持续性。研究将寻求经济上可行的脱盐策略，使用可再生碳资源，并将重点放在克服知识差距上，这些知识差距限制了我们设计节能和经济有效的膜电容去离子系统的能力。这一框架将用于向本科生和高中生传授水资源短缺、可持续水资源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，同时增加从再生和含盐水源中回收水，对于尽量减少经济成本和环境影响至关重要。这项工作的总目标是通过解决咸淡水和再生水淡化的现有经济和能源障碍，增加水资源紧张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耦合到电容器电极的充电和放电，膜电容去离子系统有可能从海水淡化的热力学极限附近去除离子，所需的能量远低于反渗透。由于反渗透的能源、维护和盐水处理成本，从低盐度来源（即微咸水和再生废水）生产饮用水目前在大多数地区在经济上是不可实现的。本研究旨在解决目前限制膜电容去离子的关键障碍，这是一种潜在的低成本和可持续的反渗透替代方案，通过在集成建模和定量可持续设计框架内开发新的电极几何形状和操作方案，将微观结构组成、反应器设计和操作决策与处理效果、淡水生产成本和环境可持续性预测联系起来。假设是，基于电容器的去离子可能使从咸淡水和再生水生产淡水的能源效率和成本效益。本工作的目标是：i)通过综合建模和实验揭示膜电容去离子系统中电化学能量损失的机制；Ii)开发新型高性能电极形态，解决主要的能量损失机制；Iii)开发一种膜电容去离子过程模型，以校准能源和水回收技术的极限；并且，iv)通过将过程模型整合到一个定量的可持续设计框架中，在不确定性下整合环境、经济和性能指标，为膜电容去离子的发展建立一条前进的道路。

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.