Abstract: A process is provided for the reduction roasting of ores using a C.sub.2 to C.sub.8 hydrocarbon. The process is particularly applicable to manganese dioxide containing ores and provides enhanced reduction of the manganese to lower oxidation states at low operating temperatures for manganese dioxide ores and provides increased silver recoveries from refractory manganese-silver ores.
Type:
Grant
Filed:
July 20, 1988
Date of Patent:
January 15, 1991
Assignee:
ASARCO Incorporated
Inventors:
Mamdouh M. El Tawil, Adrian E. Albrethsen
Abstract: The method of making copper rod by rolling is significantly improved by effectively controlling the water-soluble oil emulsion used to lubricate the rolls by employing a conductivity probe to maintain the conductivity of the emulsion within desired operating limits.
Abstract: A mobile truck for moving containers and other articles comprising a base, supporting standards at opposite sides of the base, a handle pivotally attached at the upper ends of the standards, a lift supporting member pivotally attached to the handle and to a suitable lifter arm, the lifter arm having attached at one end a lifting device and the other end of the lifter arm being pivotally attached to a connecting bar, with the other end of the connecting bar being pivotally attached to the truck base.
Type:
Grant
Filed:
December 9, 1985
Date of Patent:
February 20, 1990
Assignee:
Asarco Incorporated
Inventors:
Joseph B. Cumbest, Johnnie L. Briggs, Francis R. Jones
Abstract: Arsenic and antimony are separated from speiss by a roasting operation employing pyrite and coke and the arsenic is separated from the resultant product by a water pressure leaching operation.
Type:
Grant
Filed:
April 21, 1986
Date of Patent:
January 2, 1990
Assignee:
ASARCO Incorporated
Inventors:
Thomas P. Clement, II, John R. Wettlaufer, Jack A. Scott
Abstract: Fume generated by roasting speiss is contacted with an oxygen-containing gas at an elevated temperature for a sufficient time to produce arsenic and antimony products which may be separated from each other by means such as condensation. Further, in the roasting of antimony-containing phases (such as speiss) the presence of arsenic can enhance the volatility of the antimony.
Type:
Grant
Filed:
August 25, 1987
Date of Patent:
February 28, 1989
Assignee:
Asarco Incorporated
Inventors:
Thomas P. Clement, II, Taie Li, John P. Hager
Abstract: The invention relates to an improved electrodeposition process for the recovery of metals by controlling the concentration of certain impurities in the electrolyte. For a zinc sulfate electrolyte, control of only the antimony impurity level below a predetermined value provides an efficient electrodeposition process.
Abstract: A process is provided for increasing the strength of antimony-lead alloys by specially treating an alloy which contains an effective amount of arsenic in the alloy, the process comprising working the alloy, rapidly heat treating the alloy, which includes quenching, for a period of time sufficient to activate a strengthening mechanism in the alloy. The process is especially useful for the manufacture of battery grids on a continuous production line.
Abstract: Gold sand resulting from the nitric acid treatment of silver refinery slimes is purified by washing with hydrochloric acid under controlled operating conditions. Platinum and other precious metals and impurities are selectively separated from the gold sand leaving a gold sand which is more efficiently refined.
Abstract: A process is provided for increasing the strength of antimony-lead alloys by specially treating an alloy which contains an effective amount of arsenic in the alloy, the process comprising working the alloy, rapidly heat treating the alloy, which includes quenching, for a period of time sufficient to activiate a strengthening mechanism in the alloy. The process is especially useful for the manufacture of battery grids on a continuous production line.
Abstract: A process for the production of a vulcanized latex protective coating bonded to the surface of an asbestos-cement article, particularly a pipe, is disclosed. The process includes a step whereby the latex coating is applied before autoclaving to the article, and becomes a hard, protective bonded layer during the autoclaving process.
Abstract: High-velocity gas burners having enhanced flame stability over wide operating ranges are provided by correlating the dimensions of the combustion chamber with other burner dimensions, in particular, the ratio of the combustion chamber diameter to the flame holder exit diameter and the ratio of the effective length of the combustion chamber to the combustion chamber diameter.
Abstract: Lead is separated from material containing lead sulfide, e.g., galena ore concentrate, by a substantially autogenous process involving establishing a pool of molten lead in a kettle, adding a metallic alkali metal, e.g., metallic sodium, to the molten lead in an amount sufficient to reduce the combined lead of the lead sulfide to metallic lead, adding the ore concentrate to the molten lead pool, and mixing together the metallic sodium, molten lead and ore concentrate. The sodium reacts rapidly and exothermically with the lead sulfide to reduce the combined lead of the lead sulfide to metallic lead and form sodium sulfide. The thus-liberated metallic lead reports in the molten lead pool, and a matte phase containing the sodium sulfide separates from the molten lead and forms on the surface of the molten lead pool.
Type:
Grant
Filed:
March 21, 1983
Date of Patent:
June 4, 1985
Assignee:
ASARCO Incorporated
Inventors:
Carl R. Di Martini, Herbert E. Howe, William L. Scott, Leo J. Bulvanoski
Abstract: A process for precise controlling of thiourea concentrations in a copper sulfate, sulfuric acid solution used in copper refining has permitted improvements in tankhouse current efficiencies and the quality of the refined copper deposited on the cathodes.
Abstract: A sintering machine for pulverulent ore concentrates containing sulfidic metals including an ignition zone, a sintering zone and at least two cooling zones wherein there is total recirculation of cooling gases between two cooling zones and including a recuperative heat exchanger for cooling the exhaust gas from the first cooling zone, prior to its introduction to the second cooling zone.
Abstract: The invention relates to an electrode for use in electrometallurgical processes, particularly for use as an anode in copper electrorefining to deposit copper onto starting blanks to make starting sheets or cathode products. The electrode is characterized by having a continuous planar configuration having a top, bottom and two vertical sides with two integral, distinct and separate legs extending from the bottom and adjacent to each of said vertical sides.
Abstract: A process for the production of a vulcanized latex protective coating bonded to the surface of an asbestos-cement article, particularly a pipe, is disclosed. The process includes a step whereby the latex coating is applied before autoclaving to the article, and becomes a hard, protective bonded layer during the autoclaving process.
Abstract: A process for precise controlling of thiourea concentrations in a copper sulfate, sulfuric acid solution used in copper refining has permitted improvements in tankhouse current efficiencies and the quality of the refined copper deposited on the cathodes.
Abstract: A method for the introduction of sodium into lead bullion followed by controlled solidification results in higher recovery of lead from the matte and speiss, and the elimination of the expensive undesirable dross reverberatory practice.
Abstract: A bismuth-lead alloy containing lesser amounts of tin, antimony and zinc has been developed for use as a fusible metal, and particularly as a jewel metal alloy. The alloy meets the standards set by presently available jewel metals, has a lower melting temperature, better casting properties, and is less expensive than currently used alloys.
Abstract: A sintering machine for pulverulent ore concentrates containing sulfidic metals including an ignition zone, a sintering zone and at least two cooling zones wherein there is total recirculation of cooling gases between two cooling zones and including a recuperative heat exchanger for cooling the exhaust gas from the first cooling zone, prior to its introduction to the second cooling zone.