The second law efficiency is a main tool for evaluating the irreversibility through a system. Models have been applied for multistage flash (MSF) and mechanical vapor compression (MVC) distillation for evaluating the entropy generation at each component in the process. The minimum work of separation (which is the work consider to extract a unit of pure water from a saline feed water) is considered through the study, the entropy generated due to irreversibility plus that of the in-equilibrium of the discharge brine and its mixing with the seawater are important during the calculation of the minimum separation work, its value for MSF is 0.729 kWh/m3. Exergy is a useful concept in the analysis of systems involving both thermal and mechanical energies. The thermal performance of distillers is assessed based on the first and second laws of thermodynamics. This study focused on the analysis of the energy and exergy of MSF and MVC units. The exergy losses due to irreversibility for the subsystems of the units are evaluated, the specific exergy losses of the MSF unit is at the range of 63 kJ/kg. The exergy destruction in heat recovery and heat rejection sections, brine heater and all the other systems are calculated, these values are 61, 17, 10, and 12% respectively. The study showed that, the second law efficiencies of the MSF unit is around 4 % and for the MVC is around 7%, so these law efficiencies clarify that there are many ways to improve the plant performance by reducing the highest exergy destruction through these systems.
Published in |
International Journal of Environmental Protection and Policy (Volume 2, Issue 6-1)
This article belongs to the Special Issue Energy, Environmental and Climate Policy |
DOI | 10.11648/j.ijepp.s.2014020601.13 |
Page(s) | 16-25 |
Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
Copyright |
Copyright © The Author(s), 2015. Published by Science Publishing Group |
Multistage Flash Distillation, Exergy, Second Law Efficiency, Separation Work, MVC
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APA Style
Adel K. El-Feky. (2015). A Comprehensive Micro-Thermal Analysis of Thermal Desalination Plants for Improving their Efficiency. International Journal of Environmental Protection and Policy, 2(6-1), 16-25. https://doi.org/10.11648/j.ijepp.s.2014020601.13
ACS Style
Adel K. El-Feky. A Comprehensive Micro-Thermal Analysis of Thermal Desalination Plants for Improving their Efficiency. Int. J. Environ. Prot. Policy 2015, 2(6-1), 16-25. doi: 10.11648/j.ijepp.s.2014020601.13
@article{10.11648/j.ijepp.s.2014020601.13, author = {Adel K. El-Feky}, title = {A Comprehensive Micro-Thermal Analysis of Thermal Desalination Plants for Improving their Efficiency}, journal = {International Journal of Environmental Protection and Policy}, volume = {2}, number = {6-1}, pages = {16-25}, doi = {10.11648/j.ijepp.s.2014020601.13}, url = {https://doi.org/10.11648/j.ijepp.s.2014020601.13}, eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijepp.s.2014020601.13}, abstract = {The second law efficiency is a main tool for evaluating the irreversibility through a system. Models have been applied for multistage flash (MSF) and mechanical vapor compression (MVC) distillation for evaluating the entropy generation at each component in the process. The minimum work of separation (which is the work consider to extract a unit of pure water from a saline feed water) is considered through the study, the entropy generated due to irreversibility plus that of the in-equilibrium of the discharge brine and its mixing with the seawater are important during the calculation of the minimum separation work, its value for MSF is 0.729 kWh/m3. Exergy is a useful concept in the analysis of systems involving both thermal and mechanical energies. The thermal performance of distillers is assessed based on the first and second laws of thermodynamics. This study focused on the analysis of the energy and exergy of MSF and MVC units. The exergy losses due to irreversibility for the subsystems of the units are evaluated, the specific exergy losses of the MSF unit is at the range of 63 kJ/kg. The exergy destruction in heat recovery and heat rejection sections, brine heater and all the other systems are calculated, these values are 61, 17, 10, and 12% respectively. The study showed that, the second law efficiencies of the MSF unit is around 4 % and for the MVC is around 7%, so these law efficiencies clarify that there are many ways to improve the plant performance by reducing the highest exergy destruction through these systems.}, year = {2015} }
TY - JOUR T1 - A Comprehensive Micro-Thermal Analysis of Thermal Desalination Plants for Improving their Efficiency AU - Adel K. El-Feky Y1 - 2015/03/31 PY - 2015 N1 - https://doi.org/10.11648/j.ijepp.s.2014020601.13 DO - 10.11648/j.ijepp.s.2014020601.13 T2 - International Journal of Environmental Protection and Policy JF - International Journal of Environmental Protection and Policy JO - International Journal of Environmental Protection and Policy SP - 16 EP - 25 PB - Science Publishing Group SN - 2330-7536 UR - https://doi.org/10.11648/j.ijepp.s.2014020601.13 AB - The second law efficiency is a main tool for evaluating the irreversibility through a system. Models have been applied for multistage flash (MSF) and mechanical vapor compression (MVC) distillation for evaluating the entropy generation at each component in the process. The minimum work of separation (which is the work consider to extract a unit of pure water from a saline feed water) is considered through the study, the entropy generated due to irreversibility plus that of the in-equilibrium of the discharge brine and its mixing with the seawater are important during the calculation of the minimum separation work, its value for MSF is 0.729 kWh/m3. Exergy is a useful concept in the analysis of systems involving both thermal and mechanical energies. The thermal performance of distillers is assessed based on the first and second laws of thermodynamics. This study focused on the analysis of the energy and exergy of MSF and MVC units. The exergy losses due to irreversibility for the subsystems of the units are evaluated, the specific exergy losses of the MSF unit is at the range of 63 kJ/kg. The exergy destruction in heat recovery and heat rejection sections, brine heater and all the other systems are calculated, these values are 61, 17, 10, and 12% respectively. The study showed that, the second law efficiencies of the MSF unit is around 4 % and for the MVC is around 7%, so these law efficiencies clarify that there are many ways to improve the plant performance by reducing the highest exergy destruction through these systems. VL - 2 IS - 6-1 ER -