The main objective of this project is to develop a new system for desalination by forward osmosis, from brackish or marine waters. The aim is to reduce energy consumption of existing processes and ensure greater energy efficiency in the desalination process. The main disadvantage of water desalination process is the high energy requirement. Currently, energy consumption of desalination is around 1% of total national energy consumption in Spain. The main advantage of the new process to be developed in the project will be the drastic reduction of energy consumption when compared to reverse osmosis desalination plants. The overall objective is based on the following specific objectives: • Development of forward osmosis process • Development of a recovery process of extracting agent
Summary of project results
The project's main objective was to develop a new system of desalination by forward osmosis and ultrafiltration, from brackish or marine waters, in order to reduce energy consumption in existing processes, ultimately improving the process' energy efficiency. This objective comes from the need to reduce the current high energy consumption in desalination processes. Desalination is responsible for about 1% of national energy consumption, which is a disproportionate relationship. The main advantage resulting from this project is a drastic reduction in energy consumption that characterizes current desalination plants, which, as a technique most widely used is reverse osmosis. The overall objective mentioned, was based on the following specific objectives: • Development of forward osmosis process. • Development of an ultrafiltration process. According to the project results it can be concluded that the desalination process using forward osmosis is currently a technically unfeasible process, as it requires more research and development for the improvement and optimization of the membrane process to ensure high overall performance and competitiveness in relation to conventional desalination by reverse osmosis. Although forward osmosis faces serious challenges of economic performance that prevent large-scale deployment and competitiveness, in principle the process could be applied to specific situations of small plants to desalinate brackish water.
Summary of bilateral results
VESTFORSK (Norwegian subcontracting agency) contributed in the following project phases: - Phase 1. Research conducted at laboratory scale: examined choices for suitable design for the membrane and polymer. This was one of the more challenging phases (and of higher risk), both from a technical and technological perspective. The phase studied both the design and implementation of suitable membrane, and the feasibility of the polymer as the osmotic agent and its recovery through a process of membranes. - Phase 4. Final validation tests on a laboratory scale. Here, Vestforsk's participation was focused on Task 4.3: Analysis of the life cycle, in which the loads and environmental impacts associated with the process were evaluated. The life-cycle assessment has allowed combining concern for the environment with economic benefits, estimating the environmental burdens associated with the acquisition and production of the necessary raw materials (including polymer) and development of the desalination pilot plant level laboratory (prototype).