Dual priming system for a pump

A pump system comprising:

• a centrifugal pump defining a casing with an inlet, an outlet and a vacuum port, the inlet being fluidly connectable with a liquid containing reservoir;
• and a dual priming system connected with the vacuum port of the centrifugal pump, the dual priming system comprising:
• a compressed air source;
• a positive displacement pump having an inlet port and a discharge port, the inlet port being fluidly connectable with the vacuum port of the centrifugal pump, whereby selective activation of the positive displacement pump is configured to evacuate gas from the centrifugal pump casing through the vacuum port and into the inlet port of the positive displacement pump and, in turn, draw liquid from the reservoir and into the centrifugal pump casing;
• a venturi having a lower maximum vacuum generation capability than the positive displacement pump, the venturi having an inlet port, an outlet port and a suction port, the inlet port being fluidly connectable with the compressed air source and the suction port being fluidly connectable with the vacuum port of the centrifugal pump in parallel with the inlet port of the positive displacement pump, whereby selective activation of the venturi pump is configured to evacuate the gas from the centrifugal pump casing and into the suction port of the venturi and, in turn, draw the liquid from the reservoir and into the centrifugal pump casing;
• a first check valve positioned upstream and in line with the suction port of the venturi and positioned in parallel with the inlet port of the positive displacement pump, the first check valve being oriented in a closed position, substantially preventing fluid flow between the vacuum port of the centrifugal pump and the suction port of the venturi, and actuatable to an open position, permitting fluid flow from the vacuum port of the centrifugal pump to the suction port of the venturi;
• a second check valve positioned upstream and in line with the inlet port of the positive displacement pump and positioned in parallel with the first check valve, the second check valve being oriented in a closed position, substantially preventing fluid flow between the vacuum port of the centrifugal pump and the inlet port of the positive displacement pump, and actuatable to an open position, permitting fluid flow from the vacuum port of the centrifugal pump to the inlet port of the positive displacement pump;
• and a control valve positioned upstream and in-line with the venturi inlet port, the control valve having an inlet fluidly connected with the compressed air source and an outlet fluidly connected with the venturi inlet port, the control valve being actuatable between a closed position, substantially fluidly disconnecting the compressed air source from the venturi, and an open position, fluidly connecting the compressed air source with the venturi inlet port;
• the dual priming system being operational in a first mode, wherein the positive displacement pump is inactive and the venturi is activated, and a second mode, wherein the positive displacement pump is activated and the venturi is activated.

A method of priming a centrifugal pump defining a casing with an inlet, an outlet and a vacuum port, the inlet being fluidly connectable with a liquid containing reservoir, the method comprising:

• connecting a dual priming system with the vacuum port of the centrifugal pump, the dual priming system comprising:
• a compressed air source;
• a positive displacement pump having an inlet port and a discharge port, the inlet port being fluidly connectable with the vacuum port of the centrifugal pump;
• a venturi having a lower maximum vacuum generation capability than the positive displacement pump, the venturi having an inlet port, an outlet port and a suction port, the inlet port being fluidly connectable with the compressed air source and the suction port being fluidly connectable with the vacuum port of the centrifugal pump in parallel with the inlet port of the positive displacement pump;
• a first check valve positioned upstream and in line with the suction port of the venturi and positioned in parallel with the inlet port of the positive displacement pump, the first check valve being oriented in a closed position, substantially preventing fluid flow between the vacuum port of the centrifugal pump and the suction port of the venturi, and actuatable to an open position, permitting fluid flow from the vacuum port of the centrifugal pump to the suction port of the venturi;
• a second check valve positioned upstream and in line with the inlet port of the positive displacement pump and positioned in parallel with the first check valve, the second check valve being oriented in a closed position, substantially preventing fluid flow between the vacuum port of the centrifugal pump and the inlet port of the positive displacement pump, and actuatable to an open position, permitting fluid flow from the vacuum port of the centrifugal pump to the inlet port of the positive displacement pump;
• and a control valve positioned upstream and in-line with the venturi inlet port, the control valve having an inlet fluidly connected with the compressed air source and an outlet fluidly connected with the venturi inlet port, the control valve being actuatable between a closed position, substantially fluidly disconnecting the compressed air source from the venturi, and an open position, fluidly connecting the compressed air source with the venturi inlet port;
• actuating the control valve into the open position thereof to fluidly connect the compressed air source with the venturi inlet port to permit compressed air to flow into the inlet port of the venturi, and, in turn, creating a vacuum at the suction port;
• and actuating the first check valve into the open position thereof to fluidly connect the vacuum port of the centrifugal pump with the suction port of the venturi, and, in turn, evacuating gas from the centrifugal pump casing and into the suction port of the venturi, thereby drawing liquid from the reservoir and into the centrifugal pump casing.