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EP-4741669-A1 - COMPONENTS FOR SEALING AND SEALING CONCEPT FOR A PRESSURE EXCHANGER

EP4741669A1EP 4741669 A1EP4741669 A1EP 4741669A1EP-4741669-A1

Abstract

The present invention relates to thrust pad (1) for a port plate (200) configured to be used with a pressure exchanger (1000), e.g. for a sea water reverse osmosis plant. The pressure exchanger (1000) includes a rotatable drum (1001), the port plate (200) with at least a first port orifice (201), and a port flange (100; 400) with at least a first fluid passage (101; 401). The thrust pad (1) is provided to improve a sealing concept of pressure exchangers. It comprises a plate-side surface (9), a flange-side surface (11), and a lateral surface (12). A curved shape of the thrust pad (1) is configured to be arranged at least partially between the port plate (200) and the port flange (100; 400). The thrust pad (1) extends in a thickness direction (Z) less than in a first direction (X) and a second direction (Y), wherein directions (X, Y, Z) are perpendicular. The thrust pad (1) comprises a through hole (2) that is configured to fluidically connect the first port orifice (201) of the port plate (200) to the first fluid passage (101; 401) of the port flange (100; 400). The present invention also relates to a port plate arrangement (250), an assembly of a port plate arrangement (250) and a port flange (100; 400) and to a pressure exchanger (1000).

Inventors

  • HANSEN, POUL ERIK
  • ENEVOLDSEN, GEORG
  • BABU, ACHUTHAN

Assignees

  • Danfoss A/S

Dates

Publication Date
20260513
Application Date
20241107

Claims (15)

  1. Thrust pad (1) for a port plate (200) configured to be used with a pressure exchanger (1000), for example a pressure exchanger for a sea water reverse osmosis plant, wherein the pressure exchanger (1000) includes a rotatable drum (1001), said port plate (200) and a port flange (100; 400), wherein the port plate (200) has at least a first port orifice (201) and the port flange (100; 400) has at least a first fluid passage (101; 401), wherein the thrust pad (1) comprises a plate-side surface (9), a flange-side surface (11), and a lateral surface (12), wherein the thrust pad (1) comprises a curved shape configured to be arranged at least partially between the port plate (200) and the port flange (100; 400) of the pressure exchanger (1000), wherein the thrust pad (1) extends in a first direction (X), a second direction (Y), and a thickness direction (Z), wherein the second direction (Y) is defined orthogonal with respect to said first direction (X) and the thickness direction (Z) is defined orthogonal with respect to said first direction (X) and said second direction (Y), wherein the thrust pad (1) extends in the thickness direction (Z) less than in the first direction (X) and the second direction (Y), wherein the thrust pad (1) extends in the first direction (X) less than in the second direction (Y), wherein the thrust pad (1) comprises a through hole (2), and wherein the through hole (2) is configured to fluidically connect the first port orifice (201) of the port plate (200) to the first fluid passage (101; 401) of the port flange (100; 400).
  2. Thrust pad (1) according to claim 1, wherein the lateral surface (12) is provided by an inner curved contour (5) and an outer curved contour (6) extending between a first tip portion (7) and a second tip portion (8), and wherein the inner curved contour (5) and the outer curved contour (6) respectively converge at a first end point (3) and a second end point (4) of the respective tip portions (7, 8), and/or wherein the thrust pad (1) comprises a semilunar shape.
  3. Thrust pad (1) according to any one of the preceding claims, wherein the through hole (2) extends partially along the curved shape or the semilunar, curved shape of the thrust pad (1), and wherein the through hole (2) comprises a smaller extension in the first direction (X) than in the second direction (Y).
  4. Thrust pad (1) according to any one of the preceding claims, wherein the through hole (2) comprises a reniform shape.
  5. Thrust pad (1) according to any one of the preceding claims, wherein the thrust pad (1) comprises at least one resilient element (14) which is arranged at the flange-surface (11) of the thrust pad (1) and configured to be compressed along the thickness direction (Z), and wherein the at least one resilient element (14) is configured to abut against the port flange (100; 400) when the thrust pad (1) is arranged between the port flange (100; 400) and the port plate (200).
  6. Thrust pad (1) according to any one of the preceding claims, wherein the thrust pad (1) comprises a thickness defined by an extension of the thrust pad (1) along the thickness direction (Z), wherein the thickness is at least 10 times smaller than the extension of the thrust pad (1) in the first direction (X) and/or the second direction (Y), and wherein, for example, the thrust pad (1) comprises a thickness of less than 10 mm.
  7. Thrust pad (1) according to any one of the preceding claims, wherein the thrust pad (1) is provided by a composite material comprising polyether ether ketone.
  8. Port plate arrangement (250) for the pressure exchanger (1000), for example a pressure exchanger for a sea water reverse osmosis plant, wherein the pressure exchanger (1000) includes a rotatable drum (1001) and a port flange (100; 400), wherein said port flange (100; 400) has at least a first fluid passage (101; 401), wherein the port plate arrangement (250) has a port plate (200) that extends along a longitudinal axis (ZL) between a flange-side (203) of the port plate (200) and a drum-side (204) of the port plate (200) opposite to said flange-side (203), wherein the port plate (200) further comprises a first port orifice (201) and a second port orifice (202) extending between the flange-side (203) and the drum-side (204) of the port plate (200), wherein the ports orifices (201, 202) allow separate fluid flow from the flange-side (203) to the drum-side (204) of the port plate (200), wherein the port plate (200) comprises the thrust pad (1) according to any one of claims 1 to 7.
  9. Port plate arrangement (250) according to claim 8, wherein the thrust pad (1) is configured such that the through hole (2) of the thrust pad (1) forms part of the first port orifice (201).
  10. Port plate arrangement (250) according to claim 8 or 9, wherein the port plate (200) comprises polyether ether ketone, preferably the port plate (200) is made of PEEK CA30.
  11. Assembly of the port plate arrangement (250) according to any one of claims 8 to 10 and an adjacent port flange (100; 400), wherein the port flange (100; 400) includes: a plate-interface for facing the flange-side (203) of the port plate (200) with the thrust pad (1), the first fluid passage (101; 401), wherein the first fluid passage (101; 401) opens towards the port plate (200) at the plate-interface, a thrust-pad recess (105) surrounding the first fluid passage (101; 401) at the plate-interface; wherein the flange-side (203) of the port plate (200) with the thrust pad (1) faces the plate-interface of the port flange (100; 400), wherein a flange-side portion the thrust pad (1) is received in the thrust-pad recess (105) of the port flange (100; 400).
  12. Assembly according to claim 11, wherein the assembly includes a lateral sealing element (15) for lateral sealing between the flange-side portion of the thrust pad (1) and the thrust-pad recess (105), and wherein the thrust-pad recess (105) and/or the flange-side portion of the thrust pad (1) includes a circumferential recess (106) for receiving the lateral sealing element (15).
  13. Assembly according to claim 11 or 12, wherein the assembly includes an axial sealing element (16) for axial sealing between the flange-side portion of the thrust pad (1) and the thrust-pad recess (105), wherein the axial sealing element (16) is at least axially resilient.
  14. Pressure exchanger (1000) extending along a rotational axis (ZZZ) and comprising two assemblies according to any one of claims 11 to 13 and a drum (1001) with channels (1002), wherein the assemblies are arranged in opposite orientation, wherein the drum (1001) is arranged between the two assemblies and on the respective drum-sides (104) of the port plates (204), wherein the rotational axis (ZZZ) runs parallel to the longitudinal axes (ZL) of the port plates (200), wherein the channels (1002) of the drum (1001) extend parallel to the rotational axis (ZZZ), wherein the drum (1001) is rotatable about the rotational axis (ZZZ) relative to the port plates (200), and wherein the channels (1002) are configured to be fluidically connected to the fluid passages (101, 102; 401, 402) of the port flanges (100; 400) via the port orifices (201; 202) of the port plates (200) depending on rotational positions of the drum (1001).
  15. Pressure exchanger (1000) according to claim 14, wherein the pressure exchanger (1000) comprises a high-pressure side (HS) and a low-pressure (LS), and wherein the pressure exchanger (1000) is configured to allow fluid comprising a high pressure to pass from one of the port flanges (100; 400) through the through hole (2) of the thrust pad (1), through the first port (201) of the port plate (200) and into one of the channels (1002) of the drum (1001).

Description

The present invention relates to a thrust pad for a port plate configured to be used with a pressure exchanger, for example a pressure exchanger for a sea water reverse osmosis plant. Further, the present invention relates to a port plate arrangement, to an assembly of a port flange and a port plate arrangement, as well as to a pressure exchanger. Pressure exchangers, such as rotary pressure exchangers, are well-known in the art and used for energy transfer while maintaining hydraulic pressure (isobaric). In simple terms, the pressure exchangers transfer a high-pressure fluid flow into a low-pressure fluid flow. This general concept of a pressure exchanger is frequently used in reverse osmosis plants, for example in sea water reverse osmosis plants for desalinating of sea water, as energy recovery devices or energy saving devices. In this regard, the pressure exchangers use high-pressure fluid, for example high-pressure fluid expelled from a membrane of the reverse osmosis plant, to pressurize sea water, which is introduced into the pressure exchanger at low pressure, thereby feeding the membrane with sea water at high pressure. Using pressure exchangers as energy recovery devices is particularly helpful in reducing the amount of energy, i.e. in saving energy, that would otherwise be needed by a pump to pressurize the sea water. Typically, the pressure exchangers are thus integrated into a complex fluid system and fluidically connected to ducts, channels, passages, pipes or the like which transport the fluid under high pressure or the fluid under low pressure to and from the pressure exchangers. Leakages in the fluid system, especially in a transition area between fluid transportation means and, for example a drum of the (rotary) pressure exchanger may cause energy losses. Consequently, pressure exchangers known in the art are provided with a sealing concept to allow high-pressure fluid to enter or exit the pressure exchanger, preferably without leakage, however, typically with limited leakage, which decrease the efficiency of the pressure exchanger. Thus, to prevent excessive leakage, it is known to arrange sealing elements in the pressure exchanger. However, known sealing concepts often require alternating sealings, i.e. sealing elements or surfaces alternating between the high and low pressure side, have large dimensions, need many parts, are complex, heavy or simply not suitable for high pressures, for example for pressures of more than 60 bar. In particular, handling high pressures that deform sealing surfaces, such as sealing surfaces of a port flange of a pressure exchanger, may pose difficulties. Consequently, an improved sealing concept for pressure exchangers is required. Therefore, it is the object of the present invention to improve the sealing concept of pressure exchangers. In particular, it is the object of the present invention to provide an improved sealing concept for pressure exchanger that reduces leakage while allowing to operate the system at higher pressures and with higher volume flows. The object is solved by a thrust pad according to claim 1. Further, the object is solved by a port plate arrangement according to claim 8, by an assembly according to claim 11 as well as by a pressure exchanger according to claim 14. The thrust pad is for a port plate. The thrust pad is configured to be used with a pressure exchanger, for example a pressure exchanger for a sea water reverse osmosis plant. The pressure exchanger includes a rotatable drum, said port plate and a (corresponding) port flange (an adjacent port flange), wherein the port plate has at least a first orifice and the port flange has at least a first fluid passage. The thrust pad comprises a plate-side surface, a flange-side surface, and a lateral surface. The thrust pad comprises a curved shape configured to be arranged at least partially between the port plate and the port flange of the pressure exchanger. The thrust pad extends in a first direction, a second direction, and a thickness direction, wherein the second direction is defined (at least locally) orthogonal with respect to said first direction and the thickness direction is defined orthogonal with respect to said first direction and said second direction. The thrust pad extends in the thickness direction less than in the first direction and the second direction, wherein the thrust pad extends in the first direction less than in the second direction. The thrust pad comprises a through hole. The through hole is configured to fluidically connect the first port orifice of the port plate to the first fluid port of the (corresponding) port flange. Each port orifice may provide a flow passage between a flange-side of the port plate and a drum-side of the port plate, respectively. In more detail, the (corresponding) port flange may include at least two fluid passages. The fluid passages may be for fluid exchange with external elements, e.g. for supplying fluid into the pressure