Non-condensable steam discharging device

The utility model discloses a non-condensable steam discharging device which comprises an evaporator set and a water tank, the evaporator set further comprises a first-stage multi-effect evaporator, a second-stage multi-effect evaporator and a third-stage multi-effect evaporator, and the first-stage multi-effect evaporator, the second-stage multi-effect evaporator and the third-stage multi-effect evaporator are fixedly installed in an installation frame. And the first-stage multi-effect evaporator, the second-stage multi-effect evaporator and the third-stage multi-effect evaporator are respectively connected in series through a plurality of conveying pumps and connecting pipes and are connected with an external input pipeline. The second-stage multi-effect evaporator and the third-stage multi-effect evaporator are connected through the guide pipe, the control valves and the non-condensed steam discharge pipe, one end of the non-condensed steam discharge pipe is inserted into the water tank to form liquid seal