An innovative reverse osmosis desalination system using hydrostatic pressure

A description and energy efficiency analysis is presented for an innovative reverse osmosis (RO) desalination system utilizing hydrostatic pressure. Hydrostatic pressure of a water column of sufficient height to create the required pressure to drive the RO desalination system is used. The system consists of a storage tank, connecting pipes, RO module with a moving hollow piston, filter boxes, seawater storage tank, pump, and valves. The storage tank is to be placed at the top of a mountain and is to be connected to the RO module that is placed slightly above sea level. Energy efficiency analysis shows that the system energy requirement is 0.85 kWh/m3 of fresh water produced from seawater, which is much less than that required by conventional RO plants, usually 3–10 kWh/m3 of fresh water produced from seawater.