This investigation is part of the Bureau of Mines program to develop technology that emphasizes the reuse of recycled, economically important materials, including iron and steel scrap. In addition, the research helps meet the basic objective of substituting abundant domestic materials for imported strategic commodities such as fluorspar. Scrap Preheating Of the 84.6 million st … Read more
Numerous low-grade gold-silver ore deposits throughout the Western United States have been developed in the past few years. Cyanide leaching and carbon adsorption are generally used to recover the gold. Precious metals and other adsorbed metals are eluted from the carbon with dilute caustic cyanide solutions. The elution process requires elevated temperatures and in some … Read more
The importance of ferrous scrap as a resource in the domestic iron and steel industry has increased significantly during the last two decades owing to the growth of steel production in electric arc furnaces. In 1984, approximately 55 million tons of scrap was consumed in domestic steel mills, of which 56 pct was used in … Read more
The Bureau of Mines and the Nevada Bureau of Mines have investigated hydrometallurgical methods for recovering mercury metal from sulfide concentrates. Most recently, Atkinson investigated the recovery of mercury from sulfide concentrates by a CuCl2 leaching- electrolysis technique. The concentrate used in the investigation was obtained from the McDermitt Mine, the major mercury producer in … Read more
Significant amounts of cobalt, a strategic and critical metal, are present in some secondary sources such as spent copper leach solutions. The United States currently imports over 95 pct of its cobalt supply, much of it from Africa. Development of a process to recover cobalt from readily accessible spent copper leach solutions would help meet … Read more
Cobalt is a critical and strategic metal because of its essential defence related uses and the high degree of U.S. import reliance for its supply. Currently, the United States does not produce any cobalt from domestic mines. Most of the U.S. supply of cobalt is imported from the African nations of Zambia and Zaire CO-4 … Read more
The Bureau has developed a process using ion exchange to extract cobalt, a strategic and critical metal, from domestic copper leach solutions. These solutions are produced by dump or heap leaching of low-grade ores with dilute sulfuric acid and contain significant amounts of readily accessible cobalt. Although the cobalt concentrations in these streams are only … Read more
A major problem facing the metals industry in the United States and perhaps throughout the world is the disposition of waste oxide dusts generated at various stages of processing. Storage in landfills has been used most often in the past; but, as more and more of these wastes are being declared hazardous, landfill costs have … Read more
Silicon carbide (SiC) is a synthetic compound which is commercially produced by heating a mixture of metallurgical coke and high-purity silica sand to 2,400° C in an electrical resistance furnace. A method to produce SiC was first discovered in this country by E. G. Acheson in 1891 while studying the reaction of carbon with other … Read more
The extended Haulage Truck bumper was developed to provide protection to the operator in the event of a rear-end collision between trucks. This protection is necessary because the outcome of a rear-end collision between trucks often results in the rear-end of the dump body of the forward truck penetrating the cab area of the rearward … Read more