Blast-furnace gas negative pressure displacement blowing device

The utility model discloses a blast-furnace gas negative pressure displacement blowing device, which is suitable for the displacement of toxic and harmful explosive gas, such as blast-furnace gas, coke oven gas, natural gas and the like. The device comprises a pedestal, and is characterized in that: the pedestal is connected with a connecting pipe through a valve; the connecting pipe is connected with a connecting short pipe; a steam connecting pipe is arranged on the connecting short pipe; the connecting short pipe is connected with a gas raising pipe; the gas raising pipe is connected with a throat opening; the throat opening is connected with an injection pipe; the pedestal is a metal pipe which is 400mm in outer diameter and 800mm in length; the connecting pipe is a reducing pipe which is 530mm in length; the outer diameter of the throat opening is 200mm; and the injection pipe is 400mm in outer diameter and 2,000mm in length. The device is small in occupation volume, safe and quick in displacement and go