Entropy generation analysis of electrodialysis
Electrodialysis (ED) is a desalination technology with many applications. In order to better understand how the energetic performance of this technology can be improved, the various losses in the system should be quantified and characterized. This can be done by looking at the entropy generation in...
| Main Authors: | , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
Elsevier B.V.
2017
|
| Online Access: | http://hdl.handle.net/1721.1/107707 https://orcid.org/0000-0003-3559-9167 https://orcid.org/0000-0002-2901-0638 |
| _version_ | 1826209790320181248 |
|---|---|
| author | Chehayeb, Karim Malek Lienhard, John H. |
| author2 | Massachusetts Institute of Technology. Department of Mechanical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Mechanical Engineering Chehayeb, Karim Malek Lienhard, John H. |
| author_sort | Chehayeb, Karim Malek |
| collection | MIT |
| description | Electrodialysis (ED) is a desalination technology with many applications. In order to better understand how the energetic performance of this technology can be improved, the various losses in the system should be quantified and characterized. This can be done by looking at the entropy generation in ED systems. In this paper, we implement an ED model based on the Maxwell-Stefan transport model, which is the closest model to fundamental equations. We study the sources of entropy generation at different salinities, and locate areas where possible improvements need to be made under different operating conditions. In addition, we study the effect of the channel height, membrane thickness, and cell-pair voltage on the specific rate of entropy generation. We express the second-law efficiency of ED as the product of current and voltage utilization rates, and study its variation with current density. Further, we define the useful voltage that is used beneficially for separation. We derive the rate of entropy generation that is due to the passage of ions through a voltage drop, and we investigate whether voltage drops themselves can provide a good estimate of entropy generation. |
| first_indexed | 2024-09-23T14:30:24Z |
| format | Article |
| id | mit-1721.1/107707 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T14:30:24Z |
| publishDate | 2017 |
| publisher | Elsevier B.V. |
| record_format | dspace |
| spelling | mit-1721.1/1077072022-10-01T21:33:23Z Entropy generation analysis of electrodialysis Chehayeb, Karim Malek Lienhard, John H. Massachusetts Institute of Technology. Department of Mechanical Engineering Lienhard, John H Chehayeb, Karim Malek Lienhard, John H. Electrodialysis (ED) is a desalination technology with many applications. In order to better understand how the energetic performance of this technology can be improved, the various losses in the system should be quantified and characterized. This can be done by looking at the entropy generation in ED systems. In this paper, we implement an ED model based on the Maxwell-Stefan transport model, which is the closest model to fundamental equations. We study the sources of entropy generation at different salinities, and locate areas where possible improvements need to be made under different operating conditions. In addition, we study the effect of the channel height, membrane thickness, and cell-pair voltage on the specific rate of entropy generation. We express the second-law efficiency of ED as the product of current and voltage utilization rates, and study its variation with current density. Further, we define the useful voltage that is used beneficially for separation. We derive the rate of entropy generation that is due to the passage of ions through a voltage drop, and we investigate whether voltage drops themselves can provide a good estimate of entropy generation. Kuwait Foundation for the Advancement of Sciences (KFAS) (Project No. P31475EC01) 2017-03-27T13:39:56Z 2017-03-27T13:39:56Z 2017-03 2017-02 Article http://purl.org/eprint/type/JournalArticle 00119164 http://hdl.handle.net/1721.1/107707 Chehayeb, Karim M., and John H. Lienhard. “Entropy Generation Analysis of Electrodialysis.” Desalination 413 (July 2017): 184-198. https://orcid.org/0000-0003-3559-9167 https://orcid.org/0000-0002-2901-0638 en_US http://dx.doi.org/10.1016/j.desal.2017.03.001 Desalination Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf Elsevier B.V. Prof. Lienhard via Angie Locknar |
| spellingShingle | Chehayeb, Karim Malek Lienhard, John H. Entropy generation analysis of electrodialysis |
| title | Entropy generation analysis of electrodialysis |
| title_full | Entropy generation analysis of electrodialysis |
| title_fullStr | Entropy generation analysis of electrodialysis |
| title_full_unstemmed | Entropy generation analysis of electrodialysis |
| title_short | Entropy generation analysis of electrodialysis |
| title_sort | entropy generation analysis of electrodialysis |
| url | http://hdl.handle.net/1721.1/107707 https://orcid.org/0000-0003-3559-9167 https://orcid.org/0000-0002-2901-0638 |
| work_keys_str_mv | AT chehayebkarimmalek entropygenerationanalysisofelectrodialysis AT lienhardjohnh entropygenerationanalysisofelectrodialysis |