Abstract: An hydraulic energy recovery system for sea water desalinization reverse osmosis processes wherein a tube receives salt water at low pressure and a conveyor in the tube transports the low pressure liquid to a first station where the salt water is pressurized and fed to the desalinization process. The brine from the process is conveyed under pressure to a second station along the tube from which it is conveyed to a discharge. The first and second stations are maintained at high pressure, and the salt water at the inlet end and the brine at the outlet end cooperate with the conveyor to form labyrinth seals at each end of the tube so as to maintain the pressure at the first and second stations.

Abstract: A system for removing material from the bottom of a pressure vessel without relieving the vessle's pressure in which a tube connected intermediate its inlet and outlet ends to the pressure vessel receives material through the connection and into pocket means carried by a conveyor running through the tube. The conveyor carries the material to the outlet or discharge of the tube. The pocket means form moving labyrinth seals at each end of the tube for preventing vessel pressure loss through the tube.