Fluid exchange devices and related systems, and methods

A device for exchanging at least one property between at least two fluid streams, the device comprising:

• at least one high pressure inlet for receiving a fluid at a first higher pressure;
• at least one low pressure inlet for receiving a downhole fluid at a first lower pressure;
• at least one high pressure outlet for outputting the downhole fluid at a second higher pressure that is greater than the first lower pressure;
• at least one low pressure outlet for outputting the fluid at a second lower pressure that is less than the first higher pressure;
• a valve device comprising a valve actuator configured to move one or more valve members in order selectively fill and empty at least one tank in communication with the at least one low pressure outlet and the at least one high pressure inlet, wherein the valve device comprises openings configured to selectively place the at least one high pressure inlet in communication with the at least one tank, and wherein the openings are staggered along a linear path of the one or more valve members, each of the openings overlapping with at least one adjacent opening of the openings in a direction transverse to the linear path of the one or more valve members, the openings for fluid communication with the at least one tank extending through only one lateral side of the valve device, the valve device configured to:
• selectively place the fluid at the first higher pressure in communication with the downhole fluid at the first lower pressure in order to pressurize the downhole fluid to the second higher pressure;
• and
• selectively output the fluid at the second lower pressure through the at least one low pressure outlet.

A method of operating a device for exchanging pressure between at least two fluid streams, the method comprising:

• receiving a fluid at a first higher pressure into a high pressure inlet of the device;
• receiving a downhole fluid at a first lower pressure into a low pressure inlet of the device;
• placing the fluid at the first higher pressure in communication with the downhole fluid at the first lower pressure by moving an actuator of the device in order to pressurize the downhole fluid to a second higher pressure that is greater than the first lower pressure;
• moving the actuator of the device at a first speed as a valve member of the actuator approaches an opening between the high pressure inlet and the low pressure inlet;
• reducing a velocity of the actuator of the device from the first speed to a second, lower speed as the valve member of the actuator traverses the opening, wherein the opening comprises staggered openings;
• and
• intersecting only a minor portion of leading ends of the staggered openings at a time as the valve member of the actuator traverses the staggered openings.

A method of operating a device for exchanging pressure between at least two fluid streams, the method comprising:

• receiving a fluid at a first higher pressure into a high pressure inlet of the device;
• receiving a downhole fluid at a first lower pressure into a low pressure inlet of the device;
• placing the fluid at the first higher pressure in communication with the downhole fluid at the first lower pressure by moving an actuator of the device in order to pressurize the downhole fluid to a second higher pressure that is greater than the first lower pressure;
• moving one or more valve members of the device along staggered openings between the high pressure inlet and the low pressure inlet, the staggered openings being positioned on one side of the device in communication with one or more pressure-exchanging volumes along a path of the one or more valve members;
• and
• intersecting only a minor portion of leading ends of the staggered openings as the one or more valve members traverse the staggered openings;
• and
• gradually increasing an area of the staggered openings through which the fluid is flowing as the one or more valve members move from the leading ends of the staggered openings toward trailing ends of the staggered opening.