Abstract: The invented pellet reclamation process includes forming green pellets of a mixture of steel furnace dust, a carbonaceous material such as coal, charcoal, lignite, petroleum coke, or coke, and an organic binder. The green pellets are fed over a layer of burnt pellets on a rotary hearth furnace which successively conveys the pellets first through a drying and coking zone in which the pellets are dried and any volatile matter driven out of the carbonaceous material. The pellets then travel through a reduction zone where the pellets are subjected to a higher temperature at which the contained iron oxide is reduced and remains within the pellets and the zinc, lead and cadmium oxides are reduced, volatilized, re-oxidized and carried off as oxides in the waste gases. The reduced pellets (DRI) are ultimately carried into a discharge zone where they are discharged from the rotary hearth furnace. An apparatus for performing the process is also disclosed.

Abstract: An improved furnace for heating or heat-treating of particulate materials, the furnace having an elongated body, preferably vertical, forming a triskele cylinder having a desired cross-sectional area defined by four (4) circles of identical diameter, a central circle, and three (3) tangential outer circles, the center of each tangential circle symmetrically placed 120 degrees about the central circle, each of said circles being connected by tangential arcs of about the same diameter as the circles. The furnace shell is a high performance corrosion resistant nickel-base alloy, including cobalt, chromium, and silicon, whereby the critical contents of cobalt and silicon provide improved sulfidation resistance.

Abstract: A method and apparatus for recovering primary metals from pyrometallurgical process dust, in which a vertical shaft retort, situated in a furnace or afterburner associated with a pyrometallurgical apparatus, such as an inclined rotary reduction smelter, and preferably having a tapered cross-section with the larger end at the bottom, receives greenball pellets from a pelletizer, vaporizes volatile metal metals therein, and removes them to an associated volatile metal recovery apparatus, while reducing and recovering the major metal oxide components in the pellets in metallized form.

Abstract: A method and apparatus is disclosed for direct reduction of metal oxides, using a rotary kiln, fed with greenball pellets, the kiln having a feed-end and a discharge end. A first chamber within the kiln, and adjacent to the feed-end, is used for drying, preheating and indurating the greenball pellets. Greenball pellets are fed into the first chamber using a conventional mechanism. The feed-end is sealed to prevent egress of process gas from the kiln into the atmosphere and ingress of the atmosphere into the kiln. A first burner is used for drying, preheating and indurating the greenball pellets within the first chamber. A second chamber within the kiln, adjacent to and connected with the first chamber, having a diameter greater than the first chamber, is used for reducing the pellets, the second chamber being adjacent to the discharge end. A second burner may be used for reducing the pellets within the second chamber. Reduced pellets are discharged from the discharge end.

Abstract: A method and apparatus for recovering primary metals from pyrometallurgical process dust, in which a vertical shaft retort, situated in a furnace or afterburner associated with a pyrometallurgical apparatus, such as an inclined rotary reduction smelter, and preferably having a tapered cross-section with the larger end at the bottom, receives greenball pellets from a pelletizer, vaporizes volatile metal metals therein, and removes them to an associated volatile metal recovery apparatus, while reducing and recovering the major metal oxide components in the pellets in metallized form.

Abstract: The invention encompasses a pneumatic steelmaking vessle and a method for the production of steel from hot carbon-bearing metallized raw materials such as direct reduced iron. The vessle is a refractory-lined ladle, having an eccentric ladle cover with an opening on one side. Opposite the opening in the ladle cover is at least one downwardly directed oxygen lance or tuyere. The vessel is mounted on trunnions for rotation about its central axis to a generally horizontal position. The bottom of the vessel has a porous plug, and a hot metal outlet controlled by a sliding gate closure member or other convenient type closure. The vessel is used in connection with a method of steelmaking by serving as the means for transporting molten metal to melting, refining, ladle metallurgy, and teeming operations.

Abstract: A method for the pyrometallurgical treatment of environmentally hazardous steelmill flue dust and sludges to separate and recover the volatile heavy metals from the flue dust material and to convert the remaining iron into recyclable directly reduced iron pellets, or disposable non-hazardous reoxidized iron pellets, or pig iron or shot and slag. The dust is mixed with solid carbonaceous reductant and a binder, pelletized, optionally dried, and reduced in an inclined rotary reduction smelter vessel. The distilled heavy metals are reoxidized and may be selectively segregated to reduce the gangue and lead oxide contamination from the reconcentrated zinc oxide dust. The reconcentrated heavy metal oxide dust is recycled by the zinc/lead industry.

Abstract: A method for the pyrometallurgical treatment of environmentally hazardous steelmill flue dust and sludges to separate and recover the volatile heavy metals from the flue dust material and to convert the remaining iron into recyclable directly reduced iron pellets, or disposable non-hazardous reoxidized iron pellets, or pig iron or shot and slag. The dust is mixed with solid carbonaceous reductant and a binder, pelletized, optionally dried, and reduced in an inclined rotary reduction smelter vessel. The distilled heavy metals are reoxidized and may be selectively segregated to reduce the gangue and lead oxide contamination from the reconcentrated zind oxide dust. The reconcentrated heavy metal oxide dust is recycled by the zinc/lead industry.