- 行业: 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 method of refining silver in which a small reverberatory furnace with a movable bed and a fixed roof is used. The bullion is charged gradually, and the silver is refined in the same furnace where the cupellation is carried on.
Industry:Mining
A method of removing methane from mines. It consists of injecting water under pressure into a coal seam to push out the gas. Holes are drilled horizontally into the coal face and water is pumped into some of the holes at pressures varying from 200 to 650 psi (1.4 to 4.5 MPa). This forces the methane out through the other holes and also from the exposed part of the coal seam.
Industry:Mining
A method of removing methane from mines. It consists of injecting water under pressure into a coal seam to push out the gas. Holes are drilled horizontally into the coal face and water is pumped into some of the holes at pressures varying from 200 to 650 psi (1.4 to 4.5 MPa). This forces the methane out through the other holes and also from the exposed part of the coal seam.
Industry:Mining
A method of representing the curved surface of the Earth on a flat map. As the true shape of the Earth is a globe, it is impossible to make a map of large areas of the Earth's surface without some distortion.
Industry:Mining
A method of reproducing a drawing on opaque paper by printing from a photographic negative, which enables the original drawing to be enlarged or reduced.
Industry:Mining
A method of retarding an electric winder or haulage, in which a direct current is injected into the alternating-current winder motor stator during the deceleration period; the motor then acts as an alternator, and the negative load of the winding cycle is absorbed as electric power and wasted as heat in the controller.
Industry:Mining
A method of roasting carbonate iron ore in a shaft furnace. The ore sinks continuously down the furnace while a current of hot air or flue gas, with a low carbon dioxide content, is passed through the body of the ore and a current of cold air is passed upward through the lower part of the shaft, this part acting as a cooling chamber for the ore and as a preheating flue for the air, which rapidly oxidizes the ferrous oxide in the upper regions of the furnace. The quantity and temperature of the hot gases and cold air are carefully regulated, so as to keep the carbon dioxide content of the flue gas at a minimum and thereby ensure thorough roasting of the ore at the lowest possible temperature. A furnace roasting 181 to 408 t/d requires about 176,400 to 220,500 kg.cal/t (736 to 923 kg.kJ/t), giving a heat efficiency of 73%.
Industry:Mining
A method of roasting, applied to finely divided material, in which air with sufficient strength is blown through a heated bed of mineral to keep it fluid, while reaction is controlled by continuous adjustment of rate of feed, cooling water, and added fuel (including oxygen in air). Train of appliances includes instrument controls, air compressor, dust-collecting cyclones, and feed pump.
Industry:Mining
A method of roof control whereby the natural strength of the roof strata is maintained by relieving pressure in working areas and controlling transference of load to abutments that 3640 are clear of workings and roadways. The method consists of causing certain coal pillars to yield in small amounts.
Industry:Mining
A method of rotary drilling in which chilled steel shot is used as the cutting medium.
Industry:Mining
