The present disclosure relates to methodologies, systems, and devices for compressing CO.sub.2 for recycling within a CO.sub.2-based chromatography or extraction system. A bellows pump can receive CO.sub.2 in a gaseous state and can compress the CO.sub.2 into a liquid or partially liquid-vapor state using hydraulic compression. Once compressed, the liquid or liquid-vapor CO.sub.2 can be recycled within the CO.sub.2-based chromatography or extraction system.

An electrochemically actuated pump and an electrochemical actuator for use with a pump. The pump includes one of various stroke volume multiplier configuration with the pressure of a pumping fluid assisting actuation of a driving fluid bellows. The electrochemical actuator has at least one electrode fluidically coupled to the driving fluid chamber of the first pump housing and at least one electrode fluidically coupled to the driving fluid chamber of the second pump housing. Accordingly, the electrochemical actuator selectively pressurized hydrogen gas within a driving fluid chamber.

Provided is a bellows pump device that is able to reduce fall of a discharge pressure of a transport fluid during contraction operation of a bellows. The bellows pump device supplies pressurized air to a hermetic discharge-side air chamber thereby to cause a bellows disposed within the discharge-side air chamber to perform contraction operation to discharge a transport fluid, and discharges the pressurized air from the discharge-side air chamber thereby to cause the bellows to perform expansion operation to suck the transport fluid. The bellows pump device includes an electropneumatic regulator configured to adjust an air pressure of the pressurized air to be supplied to the discharge-side air chamber, such that the air pressure is increased so as to correspond to a contraction characteristic of the bellows during the contraction operation of the bellows.

Disclosed is a conveying device for fluids with an inlet and an outlet and a conveying part which is connected therebetween and can be actuated by a drive part, wherein the conveying part has a fluid-tight media-separating device with a variable chamber volume, which becomes connected in a fluid-conducting manner via its receiving chamber to the inlet or the outlet, and which, by means of the drive part, receives fluid via the inlet as part of an intake stroke, increasing the chamber volume, and discharges the received fluid via the outlet as part of a discharge stroke, reducing the size of said chamber volume.

A liquid feeding pump is disclosed, including: a pump housing defining a hydraulic chamber, and a water inlet portion and a water outlet portion allowing a first liquid to enter or to be discharged from the hydraulic chamber; a pump chamber member defining a pump chamber isolated from the hydraulic chamber, the pump chamber member being movable between a first configuration in which the pump chamber has a first volume and a second configuration in which the pump chamber has a second volume; a liquid inlet portion and a liquid outlet portion allowing a second liquid to enter or to be discharged from the pump chamber; wherein, the liquid feeding pump is configured such that the first liquid entering the hydraulic chamber via the water inlet portion can urge the pump chamber member towards its second configuration, thereby pumping the second liquid out of the pump chamber.

Provided is a bellows pump device that is able to reduce fall of a discharge pressure of a transport fluid during contraction operation of a bellows. The bellows pump device supplies pressurized air to a hermetic discharge-side air chamber thereby to cause a bellows disposed within the discharge-side air chamber to perform contraction operation to discharge a transport fluid, and discharges the pressurized air from the discharge-side air chamber thereby to cause the bellows to perform expansion operation to suck the transport fluid. The bellows pump device includes an electropneumatic regulator configured to adjust an air pressure of the pressurized air to be supplied to the discharge-side air chamber, such that the air pressure is increased so as to correspond to a contraction characteristic of the bellows during the contraction operation of the bellows.

A hydraulically driven diaphragm pumping machine (pump), in particular for water and difficult-to-pump materials, comprises at least two side-by-side pumping units. Each pumping unit comprises a hydraulically-driven pump cylinder (1,2) and a separate non-pump hydraulic drive cylinder (9,10). The pump cylinder (1,2) has a lower first end with a first inlet and outlet for fluid to be pumped and an upper second end with a second inlet and outlet for hydraulic fluid. The pump cylinder (1,2) contains a bellows (3,4) closed at its lower end and open at its upper end for communication with hydraulic fluid. The outside of the bellows (3,4) defines a space for fluid to be pumped. The bellows (3,4) of the pump cylinder (1,2) is arranged to be driven by hydraulic fluid supplied at its top end, in concertina like expansion and contraction to pump the fluid to be pumped adjacent the lower first end of the pump cylinder (1,2). The hydraulic drive cylinder (9,10) is placed side-by-side the pump cylinder (1,2). The hydraulic drive cylinder (9,10) has a lower first end associated with a hydraulic drive an upper second end containing hydraulic fluid communicating with the upper second end of the pump cylinder (1,2). The hydraulic drive terminates at its upper end with a drive piston (19,20) slidably mounted in the hydraulic drive cylinder (9,10). The hydraulic drives of the hydraulic drive cylinders (9,10) of the two pumping units are connected by a hydro-mechanical connection (25,27) designed to control drive of the hydraulic fluid to advance and retract the pistons (19,20) of each hydraulic drive cylinder (9,10).

Disclosed is a conveying device for fluids with an inlet and an outlet and a conveying part which is connected therebetween and can be actuated by a drive part, wherein the conveying part has a fluid-tight media-separating device with a variable chamber volume, which becomes connected in a fluid-conducting manner via its receiving chamber to the inlet or the outlet, and which, by means of the drive part, receives fluid via the inlet as part of an intake stroke, increasing the chamber volume, and discharges the received fluid via the outlet as part of a discharge stroke, reducing the size of said chamber volume.