Abstract: The invention disclosed is a desalination apparatus for removing salt from seawater. The apparatus operates on the principle of reverse-osmosis whereby a feed solution containing seawater is separated into a product solution of decreased salt concentration and an exhaust solution of increased concentration. An evacuated enclosure is included to reduce windage losses and power consumption.

Abstract: A cavitation nozzle assembly is described for discharging a high velocity jet of liquid with cavitation bubbles therein. The nozzle assembly includes a supply chamber having an upstream portion divergent in a downstream direction, a downstream portion convergent in the downstream direction, and a central section of generally constant cross-sectional area. The convergent portion is conical in form and encloses an angle of about 65.degree.-90.degree., more preferably 75.degree. to 85.degree. and optimally about 80.degree.. The convergent portion converges to a discharge orifice having a circular cross-section with a diameter in the range from about 1.2 mm to about 4.0 mm. In a more preferred form, liquid distribution means are provided adjacent to the discharge orifice, configured to produce a shroud of said liquid at low pressure surrounding the high velocity jet. In another preferred embodiment, the central section of the supply chamber has a diameter from about 12 mm to about 50 mm.