| 摘要 |
<p>The present invention concerns a semi-permeable membrane for pressure retarded osmosis consisting of one thin layer of a non-porous material (the diffusion skin), and one or more layers of a porous material (the porous layer), where the porous layer has a structure where porosity Æ, thickness of the membrane x(m), and tortuosity Ä, are related to one another as given by the expression: x · Ä = Æ · S
wherein S is a structure parameter, having a value of 0.0015 m or lower, porosity is more than 50% and tortuosity is less than 2.5. The membrane porous layer has a water permeability of more than 1 €¢ 10 -11 m/s. Pa and a salt permeability of less than 3 €¢ 10 -8 m/s.</p> |
