Patent ID: 7207781

Claim:
A pressure exchange device for the transfer of a fluid comprising: a housing having a low pressure inlet located at a first distal end of said housing and a low pressure outlet located a second distal end of said housing, wherein said low pressure outlet is in alignment with said low pressure inlet, said housing further comprising a high pressure inlet located at said second distal end of said housing and a high pressure outlet located at said first distal end of said housing, wherein said high pressure inlet is in alignment with said high pressure outlet; a left rotor rotatably mounted inside said housing, said left rotor having a first low pressure conduit and a first high pressure conduit therethrough, said conduits configured to align with said high pressure outlet and said low pressure inlet concurrently as said left rotor rotates; a right rotor, coaxially aligned and offset from said left rotor, rotatably mounted inside said housing, said right rotor having a second low pressure conduit and a second high pressure conduit therethrough, said conduits being configured to align with said high pressure inlet and said low pressure outlet concurrently as said right rotor rotates; a first tube sealingly placed intermediate said left rotor and said right rotor configured to communicate fluid between said first low pressure conduit and said second low pressure conduit; a second tube, sealingly placed intermediate said left rotor and said right rotor configured to communicate fluid between said first high pressure conduit and said second high pressure conduit; a spring disposed between said left rotor and said right rotor, said spring configured to bias said left and right rotor apart from each other thereby maintaining light contact with said housing; a motive force configured to rotate said left rotor and said right rotor; and, a pressurized fluid internal to said housing, said pressurized fluid acting to maintain sealing contact between said left rotor and said right rotor and a respective sealing surface of said housing.