This flow control device (60) for a liquid in a pipe comprises a hollow body (62) including an inlet port (620) and an outlet port (622) between which a liquid is able to flow. It includes at least one adjustment element able to rotate in the hollow body (62), the adjustment element comprising several rotating discs rotatably secured to one another and each pierced with several orifices having different diameters. The device (60) comprises stationary intermediate discs relative to the adjustment element and inserted between the rotating discs, the intermediate discs being pierced with at least one orifice. The adjustment element is suitable for being rotated so as to be able to place one of the orifices of the rotating discs across from the orifice of the intermediate disc.

A fluid dispenser and method of operating the same. The fluid dispenser can include a wheel driven by diluent passing along a flow path in the fluid dispenser. The wheel can be connected to a pump to pump fluid from a reservoir for dispense into the diluent. In some embodiments, the ratio of wheel rotations to pump cycles is selected to provide a desired and repeatable dilution ratio of concentrated fluid to diluent. The fluid dispenser can be portable and/or disposable, and in some embodiments is adapted for installation on an upper rim of a reservoir wall. Also, the fluid dispenser can be provided with a baffle limiting the velocity and impact of incoming diluent to the wheel driving the pump, thereby improving dosing accuracy of the dispenser in some embodiments.

A fluid dispenser and method of operating the same. The fluid dispenser can include a wheel driven by diluent passing along a flow path in the fluid dispenser. The wheel can be connected to a pump to pump fluid from a reservoir for dispense into the diluent. In some embodiments, the ratio of wheel rotations to pump cycles is selected to provide a desired and repeatable dilution ratio of concentrated fluid to diluent. The fluid dispenser can be portable and/or disposable, and in some embodiments is adapted for installation on an upper rim of a reservoir wall. Also, the fluid dispenser can be provided with a baffle limiting the velocity and impact of incoming diluent to the wheel driving the pump, thereby improving dosing accuracy of the dispenser in some embodiments.

An apparatus for dosing a fluid flow system with treatment fluid/chemicals is described. The apparatus includes a vessel; an inlet pipe or hose and an outlet pipe for coupling to the system so that fluid from the system may flow into the vessel and return into the system to flush chemicals from within the vessel and into the system. The vessel has a piston within it and the vessel wall defines a cylinder in which the piston moves under pressure of incoming fluid from a first position at which the vessel contains fluid to be dispensed into the system to a second position corresponding to substantially complete emptying of the vessel. The piston has a bypass passage through or around it that opens when the piston substantially reaches the second position so that fluid from the system may flow passed the piston when the piston is at the second position.

A system and method of injecting a chemical into a high pressure process stream without pumps or other active components. The system utilizes the differential pressure created by resistive losses of downstream components within a high pressure process stream. A bypass side stream is taken from an upstream pressure location and returned to the downstream side of the resistive inline process component. The chemical solution vessel is pressurized by the higher side of the pressure differential. The solution then passes through a flow controlling capillary tube exiting on the lower pressure differential side into the bypass stream. The high flow rate chemically diluted bypass stream then returns to the process stream at the lower differential process stream tie-in. The chemical solution is isolated from the process water pressuring the vessel by a movable separating device preventing mixing of the two fluids. The vessel can also be pressurized by gas.

Systems and method for dispensing chemical include an eductor having a diluent inlet, a chemical pickup port, a discharge port, and a venturi fluidly coupled between the diluent inlet and the discharge port; a selector valve fluidly coupled to the diluent inlet and configured to control a flow of diluent into the diluent inlet; a sensor configured to measure a flow characteristic of the flow of diluent; and a controller operatively coupled to the selector valve. The controller includes at least one processor and memory storing instructions that, when executed, cause the at least one processor to perform operations including opening the selector valve to allow the flow of diluent into the diluent inlet; determining a dispense duration based on the measured flow characteristic and an amount of a chemical to be dispensed; and in response to determining that the dispense duration has elapsed, closing the selector valve.