Abstract: An apparatus for equalizing top gas pressure exerted on the bottom surface of the large bell operating in the large bell hopper in a top closing device for a blast furnace, so as to enable opening of the large bell for the feeding of charge therethrough during operation of the blast furnace of any top gas pressure, including a venturi scrubber, located at the top or in the vicinity of the blast furnace, connected by ducts to the uptake or other gas main for furnace top gas, and a separator, mounted at the top or in the vicinity of the blast furnace, connected by ducts to the venturi scrubber and large bell hopper, which elements scrub the furnace top gas and direct scrubbed top gas into the large bell hopper, so as to exert equalizing pressure on the large bell with scrubbed top gas, and further including an ejector, mounted in the venturi scrubber, which maintains a continuous flow of scrubbed top gas into the large bell hopper, so as to maintain equalizing pressure therein.

Abstract: An apparatus located at the top of a blast furnace for equalizing pressure exerted by top gas, generated during operation of the blast furnace, on the bottom surface of the large bell movably mounted in the top of the blast furnace, operable so as to remove pollutants from the top gas and direct the top gas with the pollutants removed therefrom into the large bell hopper at full furnace pressure to exert equalizing pressure on the top surface of the large bell to enable opening of the large bell for feeding charge therethrough into the blast furnace.