ASARCO process

Basic Data, 590 Sulphidine Rnocess, 591 ASARCO Process, 593 CANSOLV Process, 595 Dow Process, 596... 

Four processes that remove sulfur dioxide from gases using amines are described here. These are the Sulphidine, ASARCX), Dow, and Union Carbide processes. The Sulphidine process was operational prior to World War II while the ASARCO process has been commercial since the late 1940s. Both the Dow and Union Carbide s CANSOLV processes are more recent developments which use proprietary amines. 

Reformed natural gas reduces sulfur dioxide in a process developed by Asarco (231). 

The Bunker Hill Co. (15) and ASARCO, Inc. (16) have developed processes for the leaching and electrowinning of antimony from tetrahedrite ores. As of 1991, only Sunshine Mining Co. was electrowinning antimony metal. 

ASARCO [American Smelting and Refining Company] This large metallurgical company has given its name to a flue-gas desulfurization process in which the sulfur dioxide is absorbed in dimethylaniline and subsequently desorbed at a higher temperature. Operated in California, Tennessee, and Norway. 

Similar acid-base chemistry is involved in the American Smelting and Refining Company s (ASARCO s) sulfur dioxide capture process using aqueous dimethylaniline (Eq. 3.25). 

The use of cyclic absorption processes for concentrating sulfur dioxide from smelter gases is still very limited. If and when sulfur dioxide reduction is practiced, concentration processes must be used more extensively unless metallurgical processes are used that deliver richer off-gases, probably with sulfur dioxide concentrations not lower than 20-25%. The Asarco DMA absorption process (9, 10) is coming into renewed use, partly to produce liquid sulfur dioxide and partly to provide enriched feed to sulfuric acid plants. 

In the ASARCO sulfur dioxide process, however, reformed natural gas is the reducer. If we assume natural gas to be comprised solely of methane, reformed natural gas formation in the process developed by Phelps Dodge Corp. may be expressed in terms of Reaction 2 ... 

Overall recovery could be increased slightly by adding a third catalytic stage. However, it was not deemed necessary to use a third stage in the ASARCO-Phelps Dodge pilot plant because it represents technology well established in the Claus process. 

The initial laboratory investigation of the process now being piloted at the ASARCO El Paso plant involved bench scale evaluations of 19 different primary sulfur dioxide reduction catalysts. Also, fixed-bed and fluid-bed catalysis were compared, and various construction materials were evaluated in the corrosive hydrogen sulfide and sulfur vapor atmosphere generated in gas phase reduction of sulfur dioxide. 

Operation was resumed at El Paso on October 28, 1973, using a 12% sulfur dioxide feed gas. Only minor operational difficulties have been encountered to date with this feed. However, curtailed natural gas use forced shutdown of the plant on several occasions. The future availability of natural gas for industrial use could limit application of the ASARCO sulfur dioxide reduction process. It is probable that a suitable reducing gas can be generated using other fossil fuels, although this alternative has yet to be proved. 

Received April 4, 1974. Certain process details and specific laboratory and pilot data have been omitted from this discussion of the ASARCO sulfur dioxide reduction process because of their proprietary nature. 

Enshield Plus, EMI shielding processes, Enthone-OMI Inc., Subs. Asarco Inc. 

ASARCO Inc., and Phelps Dodge Corporation. He is currently Principal Advisor at Rio Tinto Kennecott Utah Copper. Dr. Wang has been active in extractive metallurgy and has experience in metallurgical process development and existing operation optimization as well as troubleshooting. He is copper and precious metals refining subject matter expert. 

The first commercial installation of the standard slag fuming furnace was at the Asarco, East Helena lead smelter in Montana in 1927, and this furnace design has subsequently been applied at a number of other major lead smelters. Copper smelter slags rich in zinc are also processed in conventional slag turners such as at Boliden s Ronnskar smelter in Sweden, and at the Hin Flon smelter of Hudson Bay Mining and Smelting Company. 

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