Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-03T03:20:39.670Z Has data issue: false hasContentIssue false

Energy Conversion using electrolytic concentration gradients

Published online by Cambridge University Press:  12 August 2015

Subramaniam Chittur K
Affiliation:
Materials Physics Department, VIT University, Vellore, TN, India. Endeavour Executive Fellow, College of Engineering and Science, Victoria University, Footscray, 3011,Victoria, Australia.
Aishwarya Chandran
Affiliation:
School of Mechanical and Building Sciences, VIT University, Vellore, TN, India.
Ashwini Khandelwal
Affiliation:
School of Mechanical and Building Sciences, VIT University, Vellore, TN, India.
Sivakumar A
Affiliation:
Environmental & Analytical Chemistry Division School of Advanced Sciences, VIT University, Vellore, TN, India.
Get access

Abstract

Salinity gradient is an enormous source of clean energy. A process for potential generation from an ionic concentration gradient produced in single and multicell assembly is presented. The ionic gradient is created using a fuel cell type cell with a micro-porous ion exchange membrane, both anionic (AEM) and cationic (CEM). Various salinity gradients, Salt : Fresh, from 100 : 0 to 16000 : 0 was established using NaCl solution, in the electrode chambers. A potential of 20 mV/cm to 25 mV/cm can be realized at ambient temperatures and pressures for a bipolar AEM/CEM cell. The performance was optimized for various static and dynamic flow rates of the saline and fresh water. The cell performance can further be optimized for Membrane Electrode System (MES) morphology. A multicell unit was assembled and the results presented for various conditions like concentration gradients, flow rates and pressure. The thermodynamic and electrical efficiency needs to be evaluated for various gradients and flow rates. The relation with number of valance electrons/ ion and the potential generated changes for various dynamic condition of salinity. The higher the salinity gradient the larger is the potential generated. This is limited by the membrane characteristics. There exists a monotonic relation between the number of valence electron/ion/unit time and the potential generated up to about 16000 concentration. The membrane characteristics have been studied for optimal ion crossover for various gradients and flow. The graph between ln (gradient) versus Voltage provides insights into this process. This presents a very cost effective and clean process of energy conversion.

Type
Articles
Copyright
Copyright © Materials Research Society 2015 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

PATTLE, R. E.. Production of Electric Power by mixing Fresh and Salt Water in the Hydroelectric Pile. Nature, 174(4431):660660, October 1954.CrossRefGoogle Scholar
Lacey, R.E.. Energy by reverse electrodialysis. Ocean Eng., 7(1):147, January 1980.CrossRefGoogle Scholar
Turek, M. and Bandura, B.. Renewable energy by reverse electrodialysis. Desalination, 205(1-3):6774, February 2007.CrossRefGoogle Scholar
Brauns, E.. Salinity gradient power by reverse electrodialysis: effect of model parameters on electrical power output. Desalination, 237(1-3):378391, February 2009.CrossRefGoogle Scholar
Veerman, Joost, Saakes, Michel, Metz, Sybrand J, and Jan Harmsen, G. Electrical power from sea and river water by reverse electrodialysis: a first step from the laboratory to a real power plant. Environ. Sci. Technol., 44(23):9207–12, December 2010.CrossRefGoogle Scholar
Post, Jan W., Hamelers, Hubertus V. M., and Buisman, Cees J. N.. Energy Recovery from Controlled Mixing Salt and FreshWater with a Reverse Electrodialysis System. Environ. Sci. Technol., 42(15):57855790, August 2008.CrossRefGoogle ScholarPubMed
Veerman, J., Saakes, M., Metz, S. J., and Harmsen, G. J.. Reverse electrodialysis: evaluation of suitable electrode systems. J. Appl. Electrochem., 40(8):14611474, April 2010.CrossRefGoogle Scholar
Vermaas, David A., Guler, Enver, Saakes, Michel, and Nijmeijer, Kitty. Theoretical power density from salinity gradients using reverse electrodialysis. Energy Procedia, 20:170184, 2012.CrossRefGoogle Scholar
Barnes, Frank S.. Cell membrane temperature rate sensitivity predicted from the Nernst equation. Bioelectromagnetics, 5(1):113115, 1984.CrossRefGoogle ScholarPubMed
Djilali, Nedjib and Lu, Dongming. Influence of heat transfer on gas and water transport in fuel cells. Int. J. Therm. Sci., 41(1):2940, January 2002.CrossRefGoogle Scholar
Walczak, Mary M., Dryer, Deborah A., Jacobson, Dana D., Foss, Michele G., and Flynn, Nolan T.. pH Dependent Redox Couple: An Illustration of the Nernst Equation. J. Chem. Educ., 74(10):1195, October 1997.CrossRefGoogle Scholar
Veerman, J., Saakes, M., Metz, S.J., and Harmsen, G.J.. Reverse electrodialysis: Performance of a stack with 50 cells on the mixing of sea and river water. J. Memb. Sci., 327(1-2):136144, February 2009.CrossRefGoogle Scholar
Dhathathreyan, K. Development of polymer electrolyte membrane fuel cell stack. Int. J. Hydrogen Energy, 24(11):11071115, November 1999.CrossRefGoogle Scholar