权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

The effect of material properties and scaling on wetting of membranes used in membrane distillation

材料特性和结垢对膜蒸馏中膜润湿的影响

基本信息

批准号：
1820389
负责人：
Amy Childress
金额：
$ 46万
依托单位：
University of Southern California
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-06-01 至 2023-05-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1820389&HistoricalAwards=false
关键词：
effect material properties scaling wetting

项目摘要

Development of energy-efficient treatment methods to treat nonconventional water sources will help to address global water scarcity. Membrane distillation can treat high-salinity and/or highly contaminated waters, for which conventional treatment processes are impractical. Membrane distillation uses low-grade energy, supplied from waste heat and/or solar thermal energy, to vaporize (rather than boil) non-potable water streams. The membrane allows water vapor to pass, while restricting permeation of liquid water and its dissolved solutes. Design of membrane distillation processes involves a number of simplifying assumptions, in particular, that the membrane is impermeable to liquid water and its dissolved solutes. However, with time, dissolved solutes form a scaling layer on the membrane, compromising the ability of the membrane to exclude liquid water and solutes. This project will develop a new model to address the performance of membrane distillation processes that is consistent with long-term operation of practical, heterogeneous membranes.This project will develop a new model for liquid entry pressure that incorporates operating conditions, membrane chemistry, asymmetric membrane properties, and the effect of a scaling layer. The model will incorporate experiments that probe internal and distillate-side membrane properties on pore wetting, simple and complex feed solution chemistries, and consider both single- and multi-component scaling conditions. Both commercial membranes and novel polymer membranes that vary hydrophobicity versus hydrophilicity will be considered. An extended Washburn method will quantify the internal hydrophobicity of the porous membranes. A techno-economic assessment will quantify the key impacts of high-performance membranes for high-salinity applications. The project will support graduate and postdoctoral training, while also expanding educational outreach to underrepresented and low-income high school students on energy-efficient water production. The project will enable better performance, prediction, and identification of membrane design improvements for challenging, high-salinity applications that approach zero liquid discharge.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

开发处理非常规水源的高能效处理方法将有助于解决全球水资源短缺问题。膜蒸馏可以处理高盐度和/或高污染的水，而传统的处理方法是不可行的。膜蒸馏使用由废热和/或太阳能提供的低级能量来汽化(而不是沸腾)非饮用水。该膜允许水蒸气通过，同时限制液态水及其溶解的溶质的渗透。膜蒸馏过程的设计涉及一些简化的假设，特别是膜对液态水及其溶解的溶质是不渗透的。然而，随着时间的推移，溶解的溶质在膜上形成一层鳞片，损害了膜排除液态水和溶质的能力。这个项目将开发一个新的模型来研究膜蒸馏过程的性能，该模型与实际的非均相膜的长期运行相一致。该项目将开发一个新的液体入口压力模型，该模型结合了操作条件、膜化学、不对称的膜特性和结垢层的影响。该模型将包括实验，探测内部和馏分侧膜的孔润湿性能，简单和复杂的进料溶液化学，并考虑单组分和多组分的结垢条件。无论是商用膜还是疏水性与亲水性不同的新型聚合物膜都将被考虑。一种扩展的沃什伯恩方法将量化多孔膜的内部疏水性。技术经济评估将量化高性能膜对高盐度应用的关键影响。该项目将支持研究生和博士后培训，同时还将教育范围扩大到代表人数不足和低收入的高中生，介绍节能用水。该项目将为具有挑战性的、接近零液体排放的高盐度应用提供更好的性能、预测和识别膜设计改进。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。