- 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 ...
Process in which oxygen is blown downwards at high velocity through a watercooled lance onto the surface of the hot metal contained in a basic lined vessel. To offset the intense heat produced, coolant materials are added with the original charge. These may be iron ore, sinter, or roll scale, but usually steel scrap is the main material used. As much as 26% of scrap may be used. After about 20 min, the charge is converted into liquid steel. During the process, tests and analyses are made and materials may be added to bring the metal to the required grade and temperature.
Industry:Mining
Headings that are turned off the main level at intervals for development purposes. They may proceed to the rise or dip and are adopted in longwall and pillar methods of working.
Industry:Mining
Feature of a rock in which the grains are more or less systematically oriented by shape. A schist in which the mica plates are parallel to one another shows a preferred orientation; so does a hornblende schist in which the long axes of the hornblende crystals are parallel.
Industry:Mining
In crushing, the ratio of the size of the largest feed particle to the smallest distance between the roll faces. As used frequently in the field, it is the ratio of the smallest aperture passing all of the feed to that passing all of the product. Another basis of expression is the ratio of the average size of feed to the average size of product.
Industry:Mining
One measure of the efficiency of a mine ventilation system is the ratio of the total amount of air actually reaching the working faces to the total amount (volume in cubic feet per minute) of air handled by the fan.
Industry:Mining
Filling lower or older workings with the waste from newer workings.
Industry:Mining
In older writings, any primary mineralized material too low in tenor to constitute ore but from which ore may be formed through secondary enrichment. As commonly employed today, the rock below the sulfide zone of supergene enrichment; the primary material 2482 that cannot be produced at a profit under existing conditions but that may become profitable with technological advances or price increases.
Industry:Mining
Hydrated chloroborate of calcium, Ca<sub>2</sub>B<sub>5</sub>O<sub>9</sub>Cl.H<sub>2</sub>O , as colorless monoclinic-domatic crystals in the rock salt of Louisiana.
Industry:Mining
Changes produced in minerals without gain or loss of components; e.g., the change from kyanite to sillimanite.
Industry:Mining
