Rotary pressure exchanger

Abstract

A pressure exchanger for transferring pressure energy from a liquid flow of one liquid system to a liquid flow of another system including a housing provided with inlet and outlet lines for liquid flows having differing pressure states, and a cylindrical rotor disposed in the housing for rotation about its longitudinal axis. The rotor has a plurality of passageways located on an annular plane surrounding the longitudinal axis of the rotor and having an opening at each axial end face of the rotor. Inlet and outlet ports for the inlet and outlet lines are arranged in the housing at the ends opposite the end faces of the rotor, and sealing zones are arranged between the inlet and outlet ports. Radially extending sealing webs are disposed on the end faces of the rotor between the passageway openings. The rotor passageways are adapted to be connected to the housing inlet and outlet ports so as to alternately conduct higher pressure liquid and lower pressure liquid from the respective liquid systems as the rotor rotates. A pressure surge-reducing afterflow zone is arranged at the transition between an inlet port and a sealing zone at the end of the housing, and/or at the transition between the end face openings of the rotor passageways and the sealing webs arranged on the rotor ends.

1 . A pressure exchanger for transferring pressure energy from a liquid stream of one liquid system to a liquid stream of another liquid system, comprising a housing with inlet and outlet lines for liquid streams having different pressure states and a cylindrical rotor disposed inside the housing so as to be rotatable about its longitudinal axis; said rotor having a plurality of passageways disposed in an annular plane surrounding the longitudinal axis of the rotor and an opening at each axial end face of the rotor; wherein 
 inlet and outlet ports for the inlet and outlet lines of the respective liquid streams are disposed in the housing at the ends of the housing opposite the rotor end faces;    sealing zones are disposed between the inlet and outlet ports of the housing;    radially extending sealing webs are arranged between the openings of the rotor passageways, and    the passageways of the rotor are adapted for communication with the inlet and outlet ports of the housing such that they alternately carry liquid under high pressure and liquid under low pressure from the respective liquid systems during rotation of the rotor, and    a pressure-surge-reducing afterflow zone is disposed at the transition between an inlet port of the housing and the sealing zone of the housing at the end of the housing or at the transition between the end-face openings of the passageways in the rotor and the sealing webs of the rotor.    
   
   
       2 . A pressure exchanger according to  claim 1 , wherein during blocking of a passageway opening by a sealing zone and upon commencement of overlap between the sealing zone and the following sealing web, the afterflow zone blocks a volumetric flow flowing into the passageway to be blocked in a time-delayed manner.  
   
   
       3 . A pressure exchanger according to  claim 1 , wherein an afterflow zone disposed on the housing at the transition between the inlet port and the sealing zone has a cross section that decreases toward the sealing zone in the direction of rotation of the rotor.  
   
   
       4 . A pressure exchanger according to  claim 3 , wherein, as viewed in the direction of rotation of the rotor, an afterflow zone is arranged adjacent that part of an inlet port which is blocked by the respective edge of the opening of a rotor passageway at the latest possible moment of an introduction of a liquid column into the rotor.  
   
   
       5 . A pressure exchanger according to  claim 1 , wherein an afterflow zone disposed on the rotor at the transition between adjacent openings of the passageways and the sealing web has an increasing cross section in the direction of rotation of the rotor.  
   
   
       6 . A pressure exchanger according to  claim 5 , wherein, as viewed in the direction of rotation of the rotor, an afterflow zone is arranged at that part of a sealing web which blocks a liquid column from the respective edge of the opening of an inlet port at the latest possible moment of an inflow of liquid into the rotor.  
   
   
       7 . A pressure exchanger according to  claim 1 , wherein the afterflow zone on the housing side has a volume characteristic that decreases toward the sealing zone.  
   
   
       8 . A pressure exchanger according to  claim 1 , wherein rotating afterflow zones have a volume characteristic that increases from the end face of the rotor toward the passageway.  
   
   
       9 . A pressure exchanger according to  claim 1 , wherein the measurable width of a sealing zone between an end of the afterflow zone and a beginning of an outlet port corresponds to at least the width of an end-face opening of a passageway and the width of a sealing web.  
   
   
       10 . A pressure exchanger according to  claim 1 , wherein, in the transition between the inlet and the outlet ports of the housing and the openings of the passageways formed in the rotor, a gap-shaped zone is arranged following an outlet edge of the inlet or outlet port as viewed in the direction of rotation of the rotor, which zone produces a low-surge blockage between the passageway opening of the rotor and the respective inlet port or outlet port of the housing.