Effect of salt concentration on permeation performance in hollow fiber type PRO membrane module

Abstract

The new sustainable power generation technique which can convert the salinity gradient energy to the hydroelectric energy is expected. This technique is called Pressure Retarded Osmosis (PRO). Clarification of the relationship between the performance of the PRO module and permeation characteristics is important. It’s already known that increase of salt concentration can increase the permeation flux through the membrane. As the conventional researches, the effects of increase of fresh water concentration and concentration polarization have evaluated. In this research, relationship between the salt concentration and membrane module is focused. The effects of fresh water dissipation and flow state of salt water in hollow fiber membrane module as new factors are researched with experiment and numerical simulation. As result, in the case of low salt concentration, permeation is not caused sufficiently in module. On the other hand, in the case of high salt concentration, very low permeation flux area exists extensively, and the effects of concentration polarization and fresh water dissipation are relatively large. Therefore salt water flow rate and module shape should be changed for each salt concentration.

Keywords

• pressure retarded osmosis(pro)
• forward osmosis(fo)
• hollow fiber
• salt concentration
• concentration polarization
• hollow fiber membrane module