Fluid exchanger devices, pressure exchangers, and related methods

A method of exchanging pressure between fluid streams, the method comprising:

• supplying a relatively high-pressure fluid into a first port formed in a first end of a housing of a pressure exchanger;
• supplying a relatively low-pressure fluid into a second port formed in a second, opposing end of the housing of the pressure exchanger;
• rotating a valve element including a first valve positioned on a first end of a plurality of stationary ducts extending along a longitudinal axis of the pressure exchanger and a second valve positioned on a second, opposing end of the plurality of stationary ducts about the plurality of stationary ducts, wherein each of the first valve and the second valve further comprises an axial port at least partially extending along the longitudinal axis of the housing, each axial port being in communication with an associated port formed in the housing extending in a direction along the longitudinal axis of the housing;
• transferring the relatively high-pressure fluid from the first port and into at least one duct of the plurality of stationary ducts with the first valve;
• transferring the relatively low-pressure fluid from the second port and into at least one duct of the plurality of stationary ducts with the second valve;
• pressurizing the relatively low-pressure fluid with the relatively high-pressure fluid to form a pressurized fluid and a spent fluid;
• transferring the pressurized fluid from the at least one duct of the plurality of stationary ducts with the second valve and outputting the pressurized fluid from the pressure exchanger through a third port formed in the second end of the housing;
• and
• transferring the spent fluid from the at least one duct of the plurality of stationary ducts with the first valve and outputting the spent fluid from the pressure exchanger through a fourth port formed in the first end of the housing.