Abstract: Processes and apparatus for reducing and pelletizing moist fine-grained ore having zinc--and/or lead-containing impurities and wherein preheated ore is discharged to a rotary furnace in which the zinc and/or lead is separated from the ore and discharged from the furnace with its exhaust gases. The zinc and/or lead is separated from the exhaust gases and the thus purified gases dry the ore prior to the preheating thereof.

Abstract: This invention relates to a fluid closure for preventing gaseous and particulate material from flowing through an opening in a fluid confining structure, and more particularly relates to a fluid curtain for sealing a lance port in a gas collecting hood for an oxygen steelmaking furnace.

Abstract: A control system for multiple burners or heaters in an afterburner section of a metal scrap dryer is provided. The control system provides for cascade and sequential control including selective and sequential ignition as well as selective and sequential deenergization of the burners or heaters.

Abstract: A pipe curtain is formed by a plurality of pipes independently suspended at one end portion to an outwardly extending flange positioned around a pollution control hood positioned at the discharge of a metallurgical furnace. Molten metal is transferred from the furnace to a metal transporting vessel through a trough, spout or the like. The hood is positioned above the trough and fans for the hood draw emissions, such as gaseous and particulate pollutants emitted from the molten metal, into the hood. The vertically suspended pipes are positioned in close relation to each other and substantially enclose the space between the bottom edge of the hood and the upper edge of the trough. With this arrangement the pipes form a curtain that prevents the air entrained pollutants emitted from the molten metal from escaping out from beneath the hood to the surrounding atmosphere.

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 flame cutting arrangement includes a cutting machine movable on a transverse track over the workpiece with the workpiece being mounted on a support table having feet in which are provided a suctioning arrangement for removing smoke gas.

Abstract: A fume extraction assembly comprises an elevated canopy adapted to collect fume; and elongated outlet means offset from an apex of the canopy and having gas flow characteristics compensating for a tendency to uncontrolled extraction rates along said outlet means.

Abstract: The generation of visible or ultraviolet chemical laser radiation is achieved by the vapor phase combustion of metal atoms. The vapor is formed in a precombustor and metal vapor is extracted from the precombustor and fed via a supersonic nozzle to the laser cavity where it is reacted with an oxidant to produce excited molecules and thereby lasing.

Abstract: A purifier for handling the high temperature effluent from a blister copper furnace, which includes solid particles in the range from 600 microns, or greater, down to a few microns, which contains oxidizable material, and which is at a high temperature, in the range of 2100.degree. to 2400.degree. F. The effluent from the blister furnace goes first to a settling chamber where the very large particles are caused to settle out by reducing the velocity of the effluent gas. The effluent then goes to a precooler tower which is an adiabatic humidifier, where the temperature is reduced to the neighborhood of 1200.degree. F. by injecting an air-driven water atomizer spray. The effluent then goes to an oxidation tower where the combustibles are oxidized, at lower than flame temperature, by injecting air and recycled gas. The effluent then goes to a conditioning tower which is a second adiabatic humidifier to further cool the gases to the neighborhood of 450.degree. F.

Abstract: Device for removing carbonizable residues includes a closed furnace heatable to low-level carbonization temperature, the furnace having an outlet for carbonization gases formed therein, means for burning off carbonization gases from carbonizable residues and utilizing the heat of combustion therefrom for heating the furnace, the means comprising a burner and a combustion chamber connected to the burner and forming part of a hot gas circulatory system, the hot gas circulatory system also including a container wherein the furnace is disposed so as to be heatable by hot gas circulating through the hot gas circulatory system, a carbonization gas return line connecting the furnace and the combustion chamber for returning to the combustion chamber carbonization gases formed in the furnace, and an inert gas line communicating with the interior of the furnace for supplying inert gas thereto.

Abstract: This invention provides a method and apparatus for exhausting rising fume from a fume-producing apparatus into a hood opening located above but laterally displaced from the fume-producing apparatus. A first jet producing a moving curtain of air is directed generally across the fume-producing apparatus from the side thereof which is remote from the hood, with the curtain at least wide enough to span substantially the whole of the rising fume. A second jet produces a second moving curtain of air travelling generally upwardly toward the hood opening from a position spaced generally beneath that opening. The energy and direction of the first jet and the resultant air curtain are such that, if the second jet were not present, the resultant paths for all portions of the air/fume mixture would traverse the general region between the hood opening and the position of which the second jet originates.

Abstract: In a method for melting a material in a vertical shaft furnace having an upper portion, a lower combustion zone portion and an intermediate post-burning portion, said upper and lower portions being separated by a restriction and wherein coke is burned and the material melted in said lower combustion zone by introducing a blast of air close to the bottom of the lower combustion zone to produce combustion gases containing CO and/or H.sub.