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United States Bureau of Mines
Industry: Mining
Number of terms: 33118
Number of blossaries: 0
Company Profile:
The U.S. Bureau of Mines (USBM) was the primary United States Government agency conducting scientific research and disseminating information on the extraction, processing, use, and conservation of mineral resources. Founded on May 16, 1910, through the Organic Act (Public Law 179), USBM's missions ...
A process sometimes used where water is scarce. The separation of free gold from the accompanying finely divided material is effected by the use of air currents.
Industry:Mining
A process step wherein granular activated carbon particles much larger than the ground ore particles are introduced into the ore pulp. Cyanide leaching and precious metals adsorption onto the activated carbon occur simultaneously. The loaded activated carbon is mechanically screened to separate it from the barren ore pulp and processed to remove the precious metals and prepare it for reuse.
Industry:Mining
A process taking place in rocks at or near their contact with a body of igneous rock. Metamorphic changes are effected by the heat and materials emanating from the magma and by some deformation connected with the emplacement of the igneous mass. Compare: thermal metamorphism; metamorphic aureole. Approx. syn: pyrometasomatism. Adj: contact-metamorphic.
Industry:Mining
A process that converts the incompletely burned hydrocarbons present in fuel exhaust into harmless gases. It involves burning up the fuel remnants with the aid of catalysts-- chemical agents, such as platinum and palladium, that speed up reactions without being consumed themselves.
Industry:Mining
A process that denotes the brittleness produced when copper containing oxide is heated in an atmosphere containing hydrogen. The hydrogen diffuses into the metal and 1326 combines with oxygen, forming steam that cannot diffuse out. A high steam pressure is built up at the crystal boundaries, and the cohesion is diminished.
Industry:Mining
A process that is designed to move the mined product (usually coal) from a continuous mining machine to a mine belt conveyor system as a continuous flow. One end of the continuous haulage system (the outby end) always remains positioned so that it discharges onto the mine belt; the other end (inby end) is free to move as the mining machine advances so as to be able to receive the product from the machine's conveyor discharge.
Industry:Mining
A process that uses an inert heavy liquid with a specific gravity between that of coal and free mineral matter to separate coarse or fine-size coal in a static bath or cyclone separator.
Industry:Mining
A process used for refining of crude nickel anodes. These are placed in reinforced concrete tanks lined with asphalt. The nickel anodes are dissolved electrochemically and the impurities, such as copper and iron, pass into solution. The cathodes are surrounded by bags of closely woven canvas duck, fastened on wooden frames, and pure nickel electrolyte is passed continuously into them to maintain a higher solution level inside the cathode compartment than outside. By this means, the pure solution flows through the pores of the bags, thus preventing the ions of copper, etc., in the solution in the anode compartment from migrating into the cathode compartment, depositing on the cathode, and preventing the refining process from taking place. The electrolyte in the anode compartments is drawn off continuously and is purified in the copper cementation and iron precipitation departments before being returned to the cathode compartments of the nickel deposition tanks.
Industry:Mining
A process used for the recovery of copper, uranium, and precious metals from weathered low-grade ore. The crushed material is laid on a slightly sloping, impervious pad and uniformly leached by the percolation of the leach liquor trickling through the beds by gravity to ponds. The metals are recovered by conventional methods from the solution.
Industry:Mining
A process used formerly for the recovery of manganese dioxide in making chlorine from hydrochloric acid in a stoneware still, by adding lime to the still liquor and oxidizing with air to precipitate a mud containing calcium manganite and yielding chlorine when recirculated and treated with hydrochloric acid.
Industry:Mining