Investigating A New Energy-Efficient Hybrid Ion Exchange-Nanofiltration (HIX-NF) Desalination Process

研究新型节能混合离子交换纳滤 (HIX-NF) 海水淡化工艺

• 批准号: 0853124
• 负责人: Arup Sengupta
• 金额: $ 18.83万
• 依托单位: Lehigh University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-05-01 至 2012-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0853124&HistoricalAwards=false
• 关键词: Investigating; New; Energy; Efficient; Hybrid

0853124SenguptaWater desalination is energy-intensive. A typical seawater reverse osmosis (RO) plant requires 1.5 to 2.5 kilowatt hours (kwh) of electricity to produce 1 m3 of treated water; a thermal distillation plant requires five to ten times more. The principal objective of this project is to develop a new hybrid ion exchange-nanofiltration (HIX-NF) process that has the potential to reduce energy consumption of water desalination by two to three times for a wide range of feed water salinities. The proposed process is innovative in its approach for it partially alters the feed water chemistry prior to the membrane treatment. Specifically, it converts chloride, the predominant anion in salt water, into sulfate through a reversible anion exchange process without requiring any regenerant. As a result, RO membranes can be replaced altogether by NF membranes resulting in a marked reduction in energy requirement. Also, NF membrane is more robust and less susceptible to fouling compared to RO, the HIX-NF process has the potential to concentrate the reject stream further, thus reducing the volume of disposable brine. The primary challenge of this research lies in engineering and perfecting the reversible sulfate-chloride anion exchange process, a significant component of the HIX-NF process. For every brackish/sea water composition, there remains a unique sulfate/chloride selectivity (i.e., separation factor value) for anion exchangers to sustain the HIX-NF process. The present body of knowledge on ion exchange fundamentals and our related work strongly suggest that by changing the sizes of the amine functional groups, the relative affinity between divalent sulfate and monovalent chloride can be greatly manipulated for an optimal process performance. In this project, rigorous experimental studies will be conducted with the three following feed water salinities to cover the entire range for the HIX-NF process: 6,000 mg/l, 12,000 mg/l and 30,000 mg/l NaCl concentrations. Two graduate students (one doctoral and one MS) will work on the project. The P.I. plans to recruit one female student from the graduating class. The P.I. gives water related lectures in science classes of Freedom High School in the Lehigh Valley. Due to its global appeal, desalination will continue to be a relevant and interesting topic for high school students.

0853124森古普塔海水淡化是能源密集型的。一个典型的海水反渗透（RO）工厂需要1.5至2.5千瓦时（kwh）的电力来生产1立方米的处理水;热蒸馏工厂需要5至10倍。该项目的主要目标是开发一种新的混合离子交换-纳滤（HIX-NF）工艺，该工艺有可能在各种供水盐度下将水脱盐的能耗降低两到三倍。所提出的工艺在其方法上是创新的，因为它在膜处理之前部分地改变了给水化学。具体而言，它通过可逆阴离子交换过程将氯化物（盐水中的主要阴离子）转化为硫酸盐，而无需任何再生剂。因此，RO膜可以完全被NF膜取代，从而显著降低了能源需求。此外，与RO相比，NF膜更坚固，不易结垢，HIX-NF工艺有可能进一步浓缩废液，从而减少一次性盐水的体积。本研究的主要挑战在于设计和完善可逆的硫酸盐-氯化物阴离子交换过程，这是HIX-NF过程的重要组成部分。对于每一种微咸水/海水组合物，仍然存在独特的硫酸盐/氯化物选择性（即，分离因子值），以维持HIX-NF工艺。关于离子交换基本原理的现有知识体系和我们的相关工作强烈表明，通过改变胺官能团的大小，可以极大地操纵二价硫酸盐和一价氯化物之间的相对亲和力以获得最佳工艺性能。在本项目中，将对以下三种给水盐度进行严格的实验研究，以涵盖HIX-NF工艺的整个范围：6，000 mg/l、12，000 mg/l和30，000 mg/l NaCl浓度。两名研究生（一名博士生和一名硕士生）将从事该项目。私家侦探计划从毕业班招收一名女生。私家侦探在利哈伊谷的自由高中的科学课上做与水有关的讲座。由于其全球吸引力，海水淡化将继续成为高中学生的相关和有趣的话题。