Waste water energy-saving utilization device of water ring vacuum pump

The utility model discloses a waste water energy-saving utilization device of a water ring vacuum pump. A cooling water tank is provided with a liquid level meter and a temperature sensor, and a blow-down valve is arranged at the bottom of the cooling water tank; the cooling water tank is provided with a low-temperature water inlet valve and a low-temperature water outlet valve, and the top of the cooling water tank is provided with a water replenishing valve and a water replenishing automatic switch valve; the cooling water tank is connected with a water inlet of the feed pump through a pipeline; a pressure gauge, a check valve and a pump water outlet valve are sequentially arranged downstream the water outlet of the water feeding pump; a pipeline connected with a water inlet of the water ring vacuum pump is arranged between the pump water outlet valve and a backflow pipeline pressure regulating valve of the cooling water tank, and pressure transmitters are sequentially arranged on the pipeline; according to