Abstract: A device for filtering dust from air drawn by apparatus from a factory shop or building, for example a steelmaking shop, including a plurality of dust extractors which have a total capacity at least equal to the air throughput of the drawn air. The extractors have regulators by which they can be regulated individually or in groups. Preferably each extractor is associated with an individual dust extractor and also each extractor preferably has its own individual cleaning system. The extractors are preferably of the dry filter bag type.

Abstract: A hood-like chamber over a converter vessel for refining pig iron, affords the collection of exhaust gases from the vessel and the direction of the gases into an exhaust gas line. The chamber is formed by a top wall containing an opening into the exhaust gas line, and side walls extend downwardly from the top wall. The lower ends of the side walls are located above the bottom of the vessel. A flange extends inwardly from the lower end of the side walls into contact with a collar extending radially outwardly from a support ring encircling the vessel. A seal can be provided between the flange and the collar to prevent the passage of air between them into the chamber. Alternatively, a gap can be left between the flange and the collar to admit a certain amount of secondary air into the chamber.

Abstract: A method for treating waste gases which are emitted from metallurgic refining methods wherein the gas is collected, cooled, cleaned and stored, and wherein the gas is removed from the refining method and treated under an excess pressure which pressure results from the refinery gas pressure. An apparatus for carrying out the method comprising a metallurgic vessel contained in a pressure vessel which is connected to a waste gas cooler and a dust separator is disclosed.

Abstract: This disclosure teaches a method for recovering reaction gases from a hydrocarbon-cooled converter which is bottom blown by oxygen. The converter comprises a vessel which is tippable between an upright position and an inclined position. The vessel is provided with bottom tuyeres and a cleaning system for the reaction gases. The method is characterized by the fact that, on tipping of the vessel, nitrogen is introduced instead of the oxygen through the bottom tuyeres whereby flushing of the cleaning system is effected. Detection means (preferably a gas analyzer) are provided to detect a predetermined increase in hydrogen content of the reaction gases during blowing and a setting ring is connectable to the vessel in sealed engagement with a suction line which forms part of the cleaning system. Control means are responsive to the detection means and are operable to connect the setting ring to the vessel and for tipping the vessel so as to flush the cleansing system.

Abstract: This disclosure teaches a process for avoiding formation of smoke and flames in bottom blown converters upon charging of scrap and pig iron, deslagging and casting. Inert gas, preferably nitrogen, is blown into the converter vessel through bottom tuyeres both during introduction of the scrap and pig iron in a tipped position of the vessel and in the vessels erected position.

Abstract: This disclosure teaches a vertically adjustable water cooled dome ring between an upper rim of a crucible and its gas trap. The gas trap has a dome with a dome opening which substantially conforms in cross section to a mouth defined by the upper rim of the crucible. The upper rim is provided with a downwardly and inwardly inclined lip. The dome ring has a seating collar adapted to engage the upper rim in a substantially gas tight manner. The seating collar is adapted to engage the upper rim about the mouth outward and in proximity of the inclined lip. Manifolds for cooling water are kept out of contact with the upper rim. A labyrinth passage is provided for entry of air between the dome and the seating collar.