Analysis and Optimization of Dual-stage Pressure Retarded Osmosis for Renewable Power Generation

This work addresses theoretical analysis and optimization of osmotic energy extracting from the concentrated brine using a pressure retarded osmosis process. The major contribution is that the existing multi-parametric optimization model is extended from the single-stage PRO process to the dual-stage PRO process. In this process, the diluted seawater from the first stage of PRO process is used as the draw solution in the second stage, while the second stage feed solution is the industrial wastewater effluent with a lower salinity. A model- based optimization method is developed to maximize the performance of PRO in terms of the normalized specific energy production. Through this work, the results show that the multi-stage PRO process is more efficient and has greater potentials in power generation in comparison with the single-stage PRO process.