Torishima Pump Mfg Co Ltd has entered into a collaboration agreement with Norway’s Waterise to provide the main pumping equipment for its subsea desalination plants. Waterise will design, install and operate subsea reverse osmosis (RO) desalination plants, which use hydrostatic pressure to push seawater through membranes creating permeate water. This will be pumped to the shore by the Torishima pumps from the Waterise subsea desalination module.
The Waterise system offers a 40% reduction on specific energy consumption (SEC) and requires 80% less land compared with conventional terrestrial RO plants. As the system is located at 500m sea depth the water entering the membranes is considerably cleaner and is a constant temperature, so it does not require the high levels of chemical treatment necessary on conventional plants.