Abstract: Systems, methods, and software program products for dispensing chemical solutions. A controller receives a signal from a pressure sensor indicative of a pressure of a diluent. The controller determines an expected flow rate of the diluent through an eductor based at least in part on the pressure of the diluent. The controller may further determine an expected concentration of a chemical product in the solution dispensed from a discharge port of the eductor. Based on the expected flow rated and concentration of the chemical product, the controller determines a duration of a dispense stage of a dispensing operation required to dispense a predetermined dose of the chemical product. The controller then causes the diluent to flow through the eductor for the determined duration of the dispense stage. A check valve on the output of the eductor prevents dissimilar chemicals from mixing and reduces a response time of the eductor.

Abstract: Systems, methods, and software program products for dispensing chemical solutions. A controller receives a signal from a pressure sensor indicative of a pressure of a diluent. The controller determines an expected flow rate of the diluent through an eductor based at least in part on the pressure of the diluent. The controller may further determine an expected concentration of a chemical product in the solution dispensed from a discharge port of the eductor. Based on the expected flow rated and concentration of the chemical product, the controller determines a duration of a dispense stage of a dispensing operation required to dispense a predetermined dose of the chemical product. The controller then causes the diluent to flow through the eductor for the determined duration of the dispense stage. A check valve on the output of the eductor prevents dissimilar chemicals from mixing and reduces a response time of the eductor.

Abstract: A chemical dispenser for a chemical dispensing system is disclosed. The chemical dispenser includes an input selector valve having an opened position and a closed position and configured to be coupled to a diluent source, a diverter valve coupled to the input selector valve, and a plurality of eductors coupled to the diverter valve. The diverter valve includes a valve head having a diluent port, a valve seat having a plurality of eductor ports, wherein each eductor port is in communication with a respective one of the plurality of eductors, and a drive mechanism coupled to the valve head and configured to move the valve head relative to the valve seat. The valve head may include one or more pressure relief ports for equalizing the diluent pressure across the valve head. A chemical dispensing system including the chemical dispenser and a method of using the chemical dispenser are also disclosed.

Abstract: A chemical proportioner comprises an eductor wherein a venturi generates a vacuum to suck chemical into a diluent and also to maintain open a diluent valve until the vacuum is automatically vented by depletion of a concentrated chemical, discharge of a predetermined diluent and chemical mix or manual venting. An expansible chamber device such as a bellows is operably connected to a diluent valve to maintain it in open position until a vacuum operating on such bellows is vented by one or more of the foregoing events.