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John H. Lienhard, V. Rehman, Danyal. Massachusetts Institute of Technology. Department of Mechanical Engineering. Massachusetts Institute of Technology. Department of Mechanical Engineering 2020-09-03T17:47:56Z 2020-09-03T17:47:56Z 2020 2020 https://hdl.handle.net/1721.1/127122 1191836908 Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, May, 2020 Cataloged from the official PDF of thesis. Includes bibliographical references (pages ). Monovalent selective electrodialysis (MSED) is a variant of conventional electrodialysis (ED) that employs selective ion exchange membranes to induce preferential removal of monovalent ions relative to divalent ions. This process can be beneficial when the divalent rich stream has potential applications. In agriculture, for example, a stream rich in calcium and magnesium is deemed beneficial for crops and can decrease dependence on fertilizers that would otherwise need to be re-introduced to the source water prior to irrigation. MSED has been used previously for salt production, brine concentration, and irrigation. An experimentally validated computational model to predict its performance, however, is not available in the literature. The proposed work uses concepts from conventional ED modelling to build a high-resolution predictive performance model for MSED. The model was validated with over 35 experiments at different operating conditions and observed to fit the data to within 6% and 8% for two different sets of membranes, respectively. The model was then used to predict selectivity, specific energy consumption, and second law efficiencies for different system conditions. An optimization study was also carried out to determine the optimal operating parameters for the MSED system. The optimized system led to a decrease in specific energy consumption and an improvement in second law efficiency of 30% relative to the bench-scale system used in the lab. by Danyal Rehman. S.M. S.M. Massachusetts Institute of Technology, Department of Mechanical Engineering 84 pages eng Massachusetts Institute of Technology MIT theses may be protected by copyright. Please reuse MIT thesis content according to the MIT Libraries Permissions Policy, which is available through the URL provided. http://dspace.mit.edu/handle/1721.1/7582 Mechanical Engineering. Monovalent selective electrodialysis : optimizing energetics for desalination and mineral recovery Optimizing energetics for desalination and mineral recovery Thesis application/pdf 2020-09-03T17:47:55Z Publication Master MechE unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="772b4a27-82c7-436d-ba59-712949a26abe"> <Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type> <Language>eng</Language> <Title>Monovalent selective electrodialysis : optimizing energetics for desalination and mineral recovery</Title> <Subtitle>Optimizing energetics for desalination and mineral recovery</Subtitle> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>2020</PublicationDate> <Authors> <Author> <DisplayName>Rehman, Danyal.</DisplayName> <Affiliation> <OrgUnit> </OrgUnit> </Affiliation> </Author> </Authors> <Editors> </Editors> <Publishers> <Publisher> <DisplayName>Massachusetts Institute of Technology</DisplayName> <OrgUnit /> </Publisher> </Publishers> <License>http://dspace.mit.edu/handle/1721.1/7582</License> <Keyword>Mechanical Engineering.</Keyword> <Abstract>Monovalent selective electrodialysis (MSED) is a variant of conventional electrodialysis (ED) that employs selective ion exchange membranes to induce preferential removal of monovalent ions relative to divalent ions. This process can be beneficial when the divalent rich stream has potential applications. In agriculture, for example, a stream rich in calcium and magnesium is deemed beneficial for crops and can decrease dependence on fertilizers that would otherwise need to be re-introduced to the source water prior to irrigation. MSED has been used previously for salt production, brine concentration, and irrigation. An experimentally validated computational model to predict its performance, however, is not available in the literature. The proposed work uses concepts from conventional ED modelling to build a high-resolution predictive performance model for MSED. The model was validated with over 35 experiments at different operating conditions and observed to fit the data to within 6% and 8% for two different sets of membranes, respectively. The model was then used to predict selectivity, specific energy consumption, and second law efficiencies for different system conditions. An optimization study was also carried out to determine the optimal operating parameters for the MSED system. The optimized system led to a decrease in specific energy consumption and an improvement in second law efficiency of 30% relative to the bench-scale system used in the lab.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>