Objectives and Problems to be Solved: Large amounts of energy can be extracted where freshwater mix with salt water. If the mixing process takes place in a pressure retarded osmosis (PRO) plant, a technical energy potential corresponding to approximately 100 m waterfall for the river water may be realised. Previous studies have focused on existing membranes made for reverse osmosis (RO). The present research project is based on the development of new membranes and the use of pressure exchange devices. The main objective of the project is to develop and test membranes suited for economic power production by mixing of fresh-water and seawater in PRO. Further, membrane mo-due-les that can secure the necessary contact between flowing water and the membrane, and with acceptable frictional losses from fluid flow will be developed. Further, the objective is to perform a feasibility study of power production by PRO using fresh water and seawater. This involves process calculations based on observed membrane performance. A plant performance model incorporating all unit operations important will be developed, based on an existing preliminary version. Results from a test unit operating in a real freshwater/sea water environment will be incorporated in this evaluation. Description of the Work: - Manufacture and basic examination of membrane samples for PRO. - Modification of existing membrane types to make them suitable for PRO. - Characterisation of the membrane samples and their performance. Measurement of water and salt permeability as well as osmotic properties.- Investigation of the influence of fluid flow in the module on PRO performance related to theoretical models. - Analysis of the equivalence of concentration and pressure differences and the mass transfer in osmosis through real membranes. Study of osmosis in biological membranes to see if new ideas can be applied in synthetic membranes.- Testing of a membrane module in a real environment of freshwater and seawater, for feasibility study utilisation purposes. Expected Results and Exploitation Plans:- Description and performance of new prototype membranes optimised for salinity power production, based on a power production of 4 W/m2 of membrane as main criteria. - A feasibility study of salinity power production, based on process calculations from measured membrane parameters and experience from running a test module.- An evaluation of the realism of development of commercial salinity power production and how an implementation may be realised.
Funding SchemeCSC - Cost-sharing contracts