Mass Transfer Resistance Analysis and Semipermeable Membrane Optimization for Pressure Retarded Osmosis

Abstract:

Salinity power is a promising renewable energy with a large amount, which can be tapped by pressure retarded osmosis(PRO), however, efficient membranes are in lack. It was reported subtrates of asymmetrical reverse osmosis(RO) membranes had severe concentration polarizations in PRO process, degrading performance greatly and limiting PRO application. Based on solute transportation equations, the paper presented a common mass transfer resistance model of osmosis process, and disclosed essential differences between PRO and RO by the comparison of resistances. In PRO water permeates through membranes against solute diffusion, which facilitates solute to accumulate in porous subtrate, as a result, subtrate mass transfer resistance is big, water flux and power density is small, especially in the case of trivial subtrate mass transfer coefficient. Commercial RO membrane CA-3000 was studied for PRO application, whose subtrate resistance was found much bigger in PRO, taking the majority of total resistance. Subtrate was optimized for PRO process and membrane performance was projected. When subtrate mass transfer coefficient was improved to 4×10^-6 m/s, power density of 4.75 W/m² was obtained with average sea water, which approached the threshold of commercial salinity power exploitation.

• Periodical: Advanced Materials Research (Volumes 361-363)
• Pages: 1416-1421
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.361-363.1416
• Online since: October 2011
• Authors: Yong Hua You, Xi Lai Zhang, Zhi Lin Wu, Xiang Fei Yu, Shi Ping Jin, Su Yi Huang
• Keywords: Mass Transfer, Pressure Retarded Osmosis, Resistance Analysis, Semipermeable Membrane Optimization

References

[1] A. Achilli and A. E. Childress，Pressure retarded osmosis: From the vision of Sidney Loeb to the first prototype installation — Review，Desalination 261 (2010) 205–211

DOI: 10.1016/j.desal.2010.06.017

[2] A. Achilli，T. Y. Cath and A. E. Childress，Power generation with pressure retarded osmosis: An experimental and theoretical investigation，Journal of Membrane Science 343 (2009) 42–52

DOI: 10.1016/j.memsci.2009.07.006

[3] Y. Xu, X. Peng, C. Y. Tang, Q. S. Fu and S. Nie，Effect of draw solution concentration and operating conditions on forward osmosis and pressure retarded osmosis performance in a spiral wound module，Journal of Membrane Science 348 (2010) 298–309

DOI: 10.1016/j.memsci.2009.11.013

[4] K. Gerstandt ,K.V. Peinemann, S. E. Skilhagen, T. Thorsen and T. Holt, Membrane processes in energy supply for an osmotic power plant, Desalination 224 (2008) 64–70

DOI: 10.1016/j.desal.2007.02.080

[5] K.L. LEE, R.W. BAKER and H.K. LONSDALE，MEMBRANES FOR POWER GENERATION BY PRESSURE-RETARDED OSMOSIS ， Journal of Membrane Science, 8 (1981) 141-171

DOI: 10.1016/s0376-7388(00)82088-8

[6] A. Seppala and M.J. Lampinen ， Thermodynamic optimizing of pressure-retarded osmosis power generation systems，Journal of Membrane Science 161(1999) 115-138

DOI: 10.1016/s0376-7388(99)00108-8

[7] Y. You, S. Huang, Y. Yang, C. Liu, Z. Wu and X. Yu, Semipermeable Membrane Mass Transfer in Pressure-Retarded Osmosis Process, 2011 2ND International Conference on Innovative Compuing and Communication and 2011 Asia-Pacific Conference on Information Technology and Ocean Engineering (ITOE-CICC 2011), vol.1(2011) 108-111

DOI: 10.1109/cicc-itoe.2010.5

[8] S. Loeb, L. Titelman, E. Korngold and J. Freiman, Effect of porous support fabric on osmosis through a Loeb-Sour irajan type asymmetric membrane, Journal of Membrane Science 129 (1997) 243-249

DOI: 10.1016/s0376-7388(96)00354-7

[9] T. Thorsen and T. Holt，The potential for power production from salinity gradients by pressure retarded osmosis，Journal of Membrane Science 335 (2009) 103–110

DOI: 10.1016/j.memsci.2009.03.003