Abstract: Volumetric pressure exchanger comprising at least one unit for pressure exchange with a hollow cylindrical body, a piston sliding in said body, said piston comprising a piston crown separating the inside of said cylindrical body into a downstream chamber and an upstream chamber, said piston comprising a rod arranged on the downstream chamber side and passing through said downstream chamber, said downstream chamber being equipped with a device for admitting and delivering water for treatment, said upstream chamber being equipped with a three-way rotary-slide valve, said rotary slide being rotated by motorized drive means, said valve comprising a pressurized-liquid supply orifice, a discharge orifice for said liquid, and an opening communicating with said upstream chamber.

Abstract: The invention relates to a valve (24) comprising: a body (40) defining a cavity and provided with a first opening (60) that makes it possible to feed water into the cavity, a second opening that makes it possible to discharge water from the cavity, and a third opening that makes it possible to connect the cavity (41) with a chamber; a stopper (49) that is rotatable inside the cavity, the stopper comprising a depression (77) on the outer surface (90) thereof that contributes to the definition of a passage enabling the flow of water between the first and third openings in first angular positions of the stopper and moreover enabling the flow of water between the second and third openings in second angular positions of the stopper, a sealing device that makes it possible to ensure a sealed stopping of the first opening (60) by means of the stopper in said second angular positions of the stopper; and a second sealing device that makes it possible to ensure a sealed stopping of the second opening by means of a stop

Abstract: The invention relates to a valve (24) comprising: a body (40) defining a cavity and provided with a first opening (60) that makes it possible to feed water into the cavity, a second opening that makes it possible to discharge water from the cavity, and a third opening that makes it possible to connect the cavity (41) with a chamber; a stopper (49) that is rotatable inside the cavity, the stopper comprising a depression (77) on the outer surface (90) thereof that contributes to the definition of a passage enabling the flow of water between the first and third openings in first angular positions of the stopper and moreover enabling the flow of water between the second and third openings in second angular positions of the stopper, a sealing device that makes it possible to ensure a sealed stopping of the first opening (60) by means of the stopper in said second angular positions of the stopper; and a second sealing device that makes it possible to ensure a sealed stopping of the second opening by means of a stop