Abstract: A method and system for recycling byproduct streams from metal processing operations introduces a flow of a molten mixture of salts, metal and metal oxides from a melting vessel into a flow of water. The molten salts dissolve into the water. The metal oxides, and any metal entrapped in the molten mixture, instantly fragment into small particles. The slurry of brine and small particles flows into a storage tank and from there the brine can be separated from the small particles by employing a series of known liquid-solid separation techniques which preferably utilize cyclones, centrifuges, thickeners, and filters. In the case of aluminum processes, an antioxidant is preferably provided in the holding tank. To increase the settling rate of the solids, a flocculent can be added in the thickener.

Abstract: A method for producing iron carbide for use as an iron source in steelmaking is provided. The method can use a wide range of feedstocks without depending on natural gas by using other forms of carbon as the carburizing source. The present method accomplishes the production of iron carbide by mixing together finely divided iron oxide containing feedstocks and carbon, pelletizing the mixture, and heating the pellets to a high temperature under reducing conditions. Preferably, the pellets are heated to a temperature of at least 1100.degree. C. Excess levels of carbon should be used in the process to assure maximum production of iron carbide.

Abstract: A method for producing iron carbide for use as an iron source in steelmaking is provided. The method can use a wide range of feedstocks without depending on natural gas by using other forms of carbon as the carburizing source. The present method accomplishes the production of iron carbide by mixing together finely divided iron oxide containing feedstocks and carbon, pelletizing the mixture, and heating the pellets to a high temperature under reducing conditions. Preferably, the pellets are heated to a temperature of at least 1100.degree. C. Excess levels of carbon should be used in the process to assure maximum production of iron carbide.

Abstract: A technique for rendering toxic metals (chromium, lead, cadmium and arsenic) contained in steel plant furnace dust innocuous and suitable for burial with minimal adverse environmental impact. Pelletized iron oxide containing dust is introduced into a rotary hearth furnace under a reducing atmosphere in excess of 600.degree. C. The higher iron oxides are reduced to FeO which in turn complexes with the toxic metals to form relatively benign products.

Abstract: A radiantly heated, travelling hearth furnace having a supplementary feed means positioned intermediate the initial loading point and the final take-off point to increase the capacity of the furnace for treating objects fed thereto. When the objects are pellets of iron oxide and carbonaceous reductant the provision of supplementary feed means about half-way along the travel path of the hearth promotes uniformity of product by inhibition of reoxidation of reduced iron by exposure to a fossil-fuel-fired furnace atmosphere.

Abstract: A countercurrent fluid cooled conveying screw is disclosed. Suitable for furnace applications, the screw includes an outer shaft spatially circumscribing an inner tube. A plurality of hollow, fluid cooled flights are affixed to the outer shaft and are in fluid flow communication with coolant coursing through the screw. The coolant is first directed through the flights and then back through the outer shaft before exiting through the inner tube.

Abstract: Discloses an improvement in furnacing objects on the top surface of an impervious rotating hearth in a directly fired rotary hearth furnace by the use of fuel burning with a luminous flame e.g., coal.

Abstract: A rotary hearth adapted to rotate in horizontal plane having a top surface made of a loose granular refractory material, advantageously dead burned dolomite grain.

Abstract: An unsupported particulate catalyst especially useful for methanation reactions is prepared by a method comprising fluid-bed roasting agglomerates of nickel sulfide to form a particulate precursor material which can be reduced to composite particles consisting essentially of a nickel-oxide core with a then coherent adherent layer of nickel thereon, the reduced particles being characterized at the surface by the presence of microcapillary pores interconnecting with each other and the outer surface of the particles.

Abstract: The invention is directed to a process for producing metal powder through atomizing in which a molten metal stream is subjected to the influence of a plurality but correlated sets of atomization jets by virtue of which a disintegrating medium exits from the jets at a velocity of at least Mach No. 1, the medium from one set of jets being angled to strike the falling molten body at a point below and at an angle less than the medium dispensed from the other set of jets, whereby less flake and filigree are formed, a higher powder yield obtains, lower medium pressure can be used, etc.

Abstract: An unsupported particulate catalyst especially useful for methanation reactions is prepared by a method comprising fluid-bed roasting agglomerates of nickel sulfide to form a particulate precursor material which can be reduced to composite particles consisting essentially of a nickel-oxide core with a then coherent adherent layer of nickel thereon, the reduced particles being characterized at the surface by the presence of microcapillary pores interconnecting with each other and the outer surface of the particles.