Drillability Index
Cost is a major criterion in decision making for selecting operational methods in mining. Knowledge of the operating cost, therefore, provides a sound basis for evaluating the feasibility of plans and for selecting alternative operational procedures. In production drilling, the choice of a drilling method is primarily based on several factors such as working condition, […]
How to Dehydrate Magnesium Chloride
The United States has almost limitless supplies of magnesium chloride available for the production of magnesium metal in the form of hydrated salts or brines from seawater, wells, and the Great Salt Lake. Anhydrous magnesium chloride has certain advantages for metal production but cannot be made from the hydrate or brines by simple drying. In […]
How to Recover Copper & Silver Sulfide Concentrate
One of the goals of the Bureau of Mines is to insure that an adequate supply of minerals is available to meet national, economic, and strategic needs. To help reach this goal, the Bureau is conducting research to advance minerals processing technology, which includes investigations for recovering metals from complex sulfide ores and concentrates. Marketing […]
How to Remove Cobalt and Nickel from Zinc Sulfate Electrolyte
The Bureau of Mines strives continually toward its goals of maximizing minerals and metals recovery from primary and secondary domestic resources, and reducing energy requirements of mining and mineral processing. This investigation to improve zinc electrolysis by separating and recovering the currently discarded cobalt and nickel found in Missouri zinc concentrates is among the Bureau’s […]
How to Chlorinate Leach Copper Chalcopyrite
The present technology for processing copper sulfide ores involves pyro-metallurgical (smelting) and to some degree hydrometallurgical techniques. Although these techniques are efficient and economical, they cause air and water pollution. Environmental concern has led the Bureau of Mines to investigate an anhydrous chlorination technique to extract Cu, Fe, and elemental S from sulfide ore without […]
How to Extract Uranium from Granite
Despite severe slippage in the growth rate of nuclear power, current estimates still show that the U.S. uranium demand will exceed the production capacity from known resources by about 1981. Projected demands also show that a fourfold to sixfold increase in uranium production will be necessary to meet the expected 1990 requirements. Surging demand and […]
Refractory Coal Flotation
There is a wide difference in the floatability of coals of different rank, and even of the same rank, depending on whether they have been freshly mined or allowed to oxidize. Also, differences in floatability, presumably due to oxidation, may occur within a particular seam because of ground water percolating through the coal bed or […]
Copper Arsenic Smelting
Copper smelting practice has not changed much over the last century. Little attention has been paid to the gas-fired reverberatory furnace because it has traditionally represented only about 10 percent of the total cost of producing copper from its ores. However, the emphasis on air pollution control, fuel shortages, and costs have generated interest in […]
Electrowon Copper Manufacturing
One aim of metallurgy research within the Federal Bureau of Mines is the advancing of metals and minerals processing technology to foster the overall goal of maintaining an adequate supply of minerals and metals to meet national economic and strategic needs. This report describes part of a research effort aimed at increasing the utilization of […]
How to Reduce Zinc Sulfide with Iron
In the quest for technological improvements in the extractive metallurgy of zinc, some efforts have been made to develop a one-step pyrometallurgical process for direct reduction of zinc sulfide to metallic zinc. The earliest endeavors were those of Eulenstein in 1912 and Peterson in 1913 who both attempted to reduce zinc sulfide with iron in […]