White Papers
Recovery of Osmotic Power in SWRO Plants
The paper analyzes the ways that different researchers have selected to overcome the phenomenon of CP, and presents an overview of the existing RO membranes from the point of view of their suitability for use in Forward Osmosis power generation.
Boris Liberman, VP & CTO Membrane Technologies
For the last two decades the attention of companies leading the desalination market has been focused mainly on energy saving. Almost half of the energy invested in the seawater desalination process is now recovered. The process of recovering gauge pressure from SWRO desalination plants started 20 years ago using the Pelton wheel has now reached 95-96% efficiency using DWEER and ERI work exchangers. In parallel, the brine of seawater RO plants contains “green fuel” in the form of high osmotic pressure that goes to waste in the brine discharge to the sea.
The theoretical possibility of recovering osmotic pressure as mechanical work power was developed by Prof. Sidney Loeb 35 years ago. This theoretical value is 1.55 kwh per cubic meter of desalinated seawater.
