No abstract

No abstract

No abstract

Pressure Retarded Osmosis (PRO) is a method for converting salinity gradients to power by allowing water to flow through a semi-permeable membrane against an applied hydraulic pressure. PRO already has a long history, starting from the middle of the last century, and has rapidly improved in recent years. In this paper, we present a historical development of PRO since its inception: the development of this renewable energy process has gone through several stages, depending on technological developments, worldwide energy demands, and environmental concerns. The technological progress of the process is also studied, as well as its cost viability and environmental impact. Finally, some ideas to further develop the PRO process and mitigate its detrimental effects are discussed.

The osmotic energy recovered by pressure-retarded osmosis from flows of different salinities is affected by the temperature, so its effect on hydrodynamic and membrane parameters is studied here. It is shown by models and experimental results that raising the temperature of the solutions leads to a variation in the mass transfer coefficient, the boundary layer, the diffusion coefficient, the solute resistivity, and the permeability, therefore, affecting the water flux. Consequently, the expected power density is improved at high temperatures, although, the salt flux diffusion increases. Laboratory results are presented using solutions at different concentrations and temperatures to validate the analysis

No abstract

No abstract

Abstract:The integration of Pressure Retarded Osmosis (PRO) with Seawater Reverse Osmosis (SWRO) is studied here, concentrating on the effect on the overall energy consumption and on the effluents. For this, two alternative designs are evaluated: a previously studied one-stage PRO (SWRO-1PRO) and a newly proposed two-stage PRO (SWRO-2PRO).The analysis results obtained from extrapolation of laboratory data using models show better performance for SWRO-2PRO (without using external impaired low-salinity water flows). The improvement of performance thanks to PRO increases with the increase of the feed concentration and flow.