Pneumatic pump control system

A method of operating a pneumatic pump control system, the method comprising:

• venting air from a pump chamber through an air valve to allow liquid to enter the pump chamber through an inlet check valve;
• permitting a liquid level within the pump chamber to rise until a predetermined high level is reached;
• introducing pressurized air into the pump chamber through the air valve to displace liquid from the pump chamber through a discharge tube;
• preventing liquid or air from flowing through the inlet check valve during pressurization of the pump chamber;
• and
• terminating introduction of pressurized air when a predetermined low liquid level within the pump chamber is detected.

A pneumatic pump control system comprising:

• a pump chamber configured to alternately receive liquid and pressurized air;
• a ventable air valve coupled to the pump chamber;
• an inlet check valve configured to permit liquid entry into the pump chamber when the pump chamber is depressurized;
• a discharge pathway including a discharge check valve configured to permit unidirectional liquid discharge;
• a pressure sensor configured to detect internal pressure conditions within the pump chamber;
• and
• a controller coupled to the pressure sensor and the air valve, the controller configured to determine pump operating states based on internal pressure conditions and to control venting and pressurization of the pump chamber in response thereto.