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: A shaft reduction furnace is provided with a pressure equalizing chamber for supplying raw materials such as ores in the furnace. The interior of the furnace is separated by a dividing plate into an upper portion and a lower portion. A pipe path through the dividing plate communicates the upper portion with lower portion. The upper portion and the pipe path form an inside ore hopper for supplying ore continuously into the lower portion of the furnace, thus omitting the conventional ore hopper of pressure-proof-structure provided separately outside of the furnace.

Abstract: A sintering plant in which sinter exhaust gases and cooling gases are collected in separate gas collecting systems. A cooling gas gas-collecting main is located beneath the lower strand of a sintering belt and is connected to opposite sides of each of the wind boxes underlying the cooling section of the sintering strand by at least two cooling gas connecting pipes, and at least one sinter exhaust gas gas-collecting main is disposed adjacent to said cooling gas gas-collecting main and connected to each of the wind boxes underlying the sintering section. Both the cooling gas gas-collecting main and the sinter exhaust gas gas-collecting main are exhausted through a plurality of gas evacuating fans and flue connecting pipes to a flue.

Abstract: A method for evaluating and/or controlling a blast furnace operation is disclosed wherein the carbon content of off-gases is measured at a test point located downstream of the wet scrubber.

Abstract: The gases emerging from a high-pressure gas furnace are subject to coarse particle separation and then to washing and scrubbing with water before driving an expansion turbine which has a gas bypass so that the turbine can be cut off. The scrubbing water recycled to the scrubber when the turbine is cut off, is permitted to traverse a cooler of the washing-water recovery unit but, when the turbine is operative, the scrubbing water bypasses the cooler. The water introduced into the scrubber can thus have a temperature of about 25.degree. C. when the turbine is bypassed and about 50.degree. C. when it is effective.

Abstract: Stack gas is first passed through a coarse-particle separator and then a prescrubbing tower. Then this gas, which is under pressure, is passed through a pair of differential-pressure (annular-gap) washers. The output side of one of the washers is connected directly to a droplet separator at the output of the system. The outlet of the other washer is connected through a turbine driving an electric generator and having its output side in turn connected to the droplet separator. The control body of at least the washer which is connected directly to the droplet separator is adjustable so as to maintain a constant backpressure in the system at the blast furnace from which the stack gas comes. The washer connected to the turbine is set up to pass at least four times as much of the gas as the other washers so that most of the gas passes through the turbine, undergoing a pressure drop that is transformed into the work of driving the turbine and generates electricity.

Abstract: A heat treatment plant comprising an assembly of refractory material adapted to receive a bath and containing a channel for a burner and optionally a channel for a flue, a framework adjacent to the refractory material, and at least one sub-frame mounted on the framework and adapted to receive a burner and flue. The burner and flue being capable of traversing the sub-frame in a direction transverse to that in which the sub-frame may traverse the framework.

Abstract: An indirectly fired vertical shaft furnace suitable for use as a volatilizing furnace for recovering metals from their ores, a crop drying or roasting furnace or a heating furnace is comprised of two concentric cylindrical metal shells each of which is closed at the upper end. The outer shell is completely lined with a lightweight insulating material and the lower end of the shell is connected to the upper end of an annular fire chamber having an upwardly open U-shaped cross-section cast from firebrick material. Two tangentially directed burners extend into the chamber to produce a swirling action of the hot gases in the heating chamber between the two cylindrical members. Conduits are provided through the top walls of both cylindrical member for withdrawing the material from the bottom of the central chamber.

Abstract: Contaminated exhaust gases being generated at a work table or work station having one or more open sides adjacent the area above the work table, and normally tending to rise into the atmosphere surrounding the work station, are collected in an exhaust hood which includes an inlet extending parallel to and generally above each of the open sides. A first portion of such exhaust gases collected are passed on to be filtered in conventional pollution abatement equipment; however, a second portion of the contaminated exhaust gases are rerouted, in some cases mixed with fresh outside air, and introduced through an air nozzle directed at the aforementioned inlet to the exhaust hood to improve the exhaust gas collecting, as well as reducing the requisite capacity of the filtration equipment and reducing the intake of make up air from the room surrounding the work table.

Abstract: Contaminated exhaust gases being generated at a work table or work station having one or more open sides adjacent the area above the work table, and normally tending to rise into the atmosphere surrounding the work station, are collected in an exhaust hood which includes an inlet extending parallel to and generally above each of the open sides. A first portion of such exhaust gases collected are passed on to be filtered in conventional pollution abatement equipment; however, a second portion of the contaminated exhaust gases are rerouted and introduced through an air nozzle directed at the aforementioned inlet to the exhaust hood to improve the exhaust gas collecting, as well as reducing the requisite capacity of the filtration equipment and reducing the intake of make up air from the room surrounding the work table.

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.

Abstract: A cold charge of steel scrap is melt cut and melted in an arc furnace provided with special oxygen-fuel burners by which rapid melting is promoted, the interior of the furnace being maintained under negative pressure by a fume evacuation and filtration means thereby to draw in secondary air from the outside atmosphere and, moreover, to increase the burner combustion efficiency. The arc furnace is provided with water cooling devices including a water-cooled ring, carbonaceous bricks, high-alumina ramming masses, and burner tiles in parts of the furnace wall and roof, particularly at wall parts where the burners are mounted, the wall above the slag line, and a roof part where an exhaust gas outlet is formed.

Abstract: An improved apparatus for cooling hot pellets discharged from a kiln or the like with water is presented wherein the pellets are charged through a chute into a water cooling bath while avoiding oxidation thereof. The cooling bath is covered with a hood and the pressure difference between the chute and hood is controlled during the process.

Abstract: Use of a shaft kiln in continuous smelting and refining of cement copper is made possible with a mix preheater, a refined gas preheater, an air preheater, an air mix feeder and forehearths for cement oxidation and reduction, and wherein oxidation is achieved by injecting oxidant gases and reduction by injecting preheated petroleum gas, subsequent to having placed a layer of charcoal on the smelt.

Abstract: An apparatus for cleaning the exhaust gas of a high-pressure blast furnace comprises a coarse-particle separator, a prewasher and a differential-pressure annular gap washer traversed in succession by the gases. The exhaust gases can be passed through a main duct provided with an expansion turbine or through a bypass duct around the expansion turbine. The expansion turbine unit controls the back pressure at the blast furnace while a separate control circuit is provided to operate the differential-pressure washer with optimum efficiency. A quick-closing valve in the turbine-supply line and a quick-opening valve in the bypass line permits rapid switchover, a pressure-control valve in the bypass line maintains a constant backpressure at the blast furnace when the expansion turbine unit is shut down.

Abstract: A textile or other industrial machine, of the type where one or a plurality of operations generate a gaseous discharge at a work station, is provided with at least one wall leaving at least one open side and includes an exhaust hood on the top which communicates with the air space above the work station. A first fan communicates with the exhaust hood to withdraw smoke, fumes, vapors and steam from the air space and deliver it to the outside. A second fan draws in fresh, unconditioned outside air and delivers it to a delivery nozzle extending along the front edge of a work table in said work station. An air curtain is thus formed between the delivery nozzle and the aforementioned exhaust hood, whereby the smoke, fumes, vapors and steam are confined within the air space above the work table until withdrawn through the exhaust hood.

Abstract: Contaminated exhaust gases being generated at a work table or work station having one or more open sides adjacent the area above the work table, and normally tending to rise into the atmosphere surrounding the work station, are collected in an exhaust hood which includes an inlet extending parallel to and generally above each of the open sides. A first portion of such exhaust gases collected are passed on to be filtered in conventional pollution abatement equipment; however, a second portion of the contaminated exhaust gases are rerouted and introduced through an air nozzle directed at the aforementioned inlet to the exhaust hood to improve the exhaust gas collecting, as well as reducing the requisite capacity of the filtration equipment and reducing the intake of make up air from the room surrounding the work table.

Abstract: In a device for the collecting and conveying of fumes emanating from a furnace having an opening therein, the device includes a fume hood disposed in communication with the furnace opening with a fume collecting reservoir extending around the fume hood, the fume collecting reservoir and the fume hood being in further fluid communication with an exhaust system, the exhaust system including means therein to selectively control the flow of fumes from the fume collecting reservoir and the fume hood.

Abstract: Apparatus for direct reduction of iron ore containing sulfur comprises a shaft type reduction furnace with means for withdrawing two separate streams of spent reducing gas. One stream, being substantially free of sulfur is recycled through a catalytic reformer to produce fresh reducing gas. The other stream containing sulfur, is connected to process equipment such as a burner where sulfur is not of consequence.

Abstract: An improved cupola furnace waste gas recuperative system and method for collecting waste furnace gases, cleaning them for the purpose of safely burning same either in a recuperator-heat exchanger for preheating incoming furnace blast air or for other heating purposes. The improvement consists of a method and means to control the pressure inside of the gas take-off chamber of an open, top charged, cupola furnace for the purposes of preventing gases from escaping through the charging hopper, preventing the indraft of excessive amounts of air, preventing explosive combustion and flashback of the waste gas and maintaining cleaning efficiency at any gas flow rate. Means include the controlled recirculation of a variable portion of the waste gas through part of the gas cleaning system and control of the furnace top gas pressure as a function of the incoming cupola furnace blast air.

Abstract: Dust-laden waste gases from a converter and from ancillary equipment are exhausted by respective blowers through a first and a second duct to a main and a secondary scrubbing station whence the purified gases escape through respective chimneys. The first duct is provided with two cascaded washing stages, the upstream stage being operable to throttle or block the flow of gases therethrough. An annular cowl for the interception of peripherally escaping converter gases is connected to a third duct which joins the first duct at a location between the two washing stages but is also connectable through a switching valve to the second duct.