Energy mineral processing

Processing costs include those for size reduction, size classification, minerals concentration and separations, soHd—Hquid separation (dewatering), materials handling and transportation, and tailings disposal. Size reduction, one of the most expensive unit operations in minerals processing, could account for as much as 50% of the total energy consumed. This cost varies considerably from deposit to deposit and quite often from one area of a deposit to another. Ore bodies are extremely heterogeneous and the associated minerals Hberation, complex. 

Size reduction (qv) or comminution is the first and very important step in the processing of most minerals (2,6,10,20—24). It also involves large expenditures for heavy equipment, energy, operation, and maintenance. Size reduction is necessary because the value minerals are intimately associated with gangue and need to be Hberated, and/or because most minerals processing/separation methods require the ore mass to be of certain size and/or shape. Size reduction is also required in the case of quarry products to produce material of controlled particle size (see Size measurement of particles). In some instances, hberation of valuables or impurities from the ore matrix is achieved without any apparent size reduction. Scmbbers and attritors used in the industrial minerals plants, eg, phosphate, mtile, glass sands, or clay, ate examples. 

Energy Use Patterns in Metallurgical andMonmetallic Mineral Processing, Report No. PB-246 357, BatteUe Columbus Laboratories, U.S. Department of Commerce, Washington, D.C., 1975. 

Energy Use Patterns in Metallurgical and Non-Metallic Mineral Processing, Phase 6—Eow Priorif Commodities, final report to U.S. Bureau of Mines, BatteUe Columbus Laboratory, Columbus, Ohio, July 1976. 

Ores are mined and are then refined in an energy intensive process to produce pure metals, which in turn are combined to make alloys (see Metallurgy Mineral RECOVERY and processing). Corrosion occurs because of the tendency of these refined materials to return to a more thermodynamically stable state (1—4). The key reaction in corrosion is the oxidation or anodic dissolution of the metal to produce metal ions and electrons... 

A novel comminution device, the roll press, has achieved commercial success [Schoenert, International J. Mineral Processing, 22, 401-412 (1988)]. It is used for fine crushing, replacing the function of a coarse-baU mill or of tertiary crushers. Unlike ordinary roll crushers which crush individual particles, the roll press is choke fed and acts on a thick stream or ribbon of feed. Particles are crushed mostly against other particles, so wear is veiy low. Energy efficiency is also greater than in ball mills. 

Battelle-Columbus Laboratories, Energy Use Patterns in Metallurgical and Nnnmetallic Mineral Processing. (197.S). High Priority Commodities, PB 24.i 7.S9 (197.i). Intermediate Prioriy Commodities PB 246 357 (1976). Low-Prioriy Commodities, PB 261 150. 

Cata, M., Ciccu, R., Delfa, G., 1973. Improvement in electric separation and flotation by modification of energy level in surface layers. 10th International Mineral Processing Congress, London, 1 1 - 22... 

Leitch, C.H.B. Lentz, D.R. 1994. The gresen approach to mass balance constraints of alteration systems methods, pitfalls, examples. In Lentz, D.R., ed) Alteration and Alteration processes associated with Ore-forming systems. Geological Association of Canada, Short Course Notes, 11, 161-192. Lentz, D.R. 1995. Preliminary evaluation of six in-house rock geochemical standards from the Bathurst Camp, New Brunswick. New Brunswick Department of Natural Resources and Energy, Minerals and Energy Division, Miscellaneous Report 18, p. 81-89. 

At low and medium doses, it is well established that the nutritional value of proteins, carbohydrates, and fats as macronutrients are not significantly impaired by irradiation, and neither the mineral bioavailability is impacted. Like all other energy depositing process, the application of ionizing radiation treatment can reduce the levels of certain sensitive vitamins. Nutrient loss can be minimized by irradiating food in a cold or frozen state and under reduced levels of oxygen. Thiamin and ascorbic acid are the most radiation sensitive, water-soluble vitamins, whereas the most sensitive, fat-soluble vitamin is vitamin E. In chilled pork cuts at the 3 kGy maximum at 0-10°C, one may expect about 35 0% loss of thiamin in frozen, uncooked pork meat irradiated at a 7 kGy maximum at —20°C approx., 35 % loss of it can be expected [122]. 

The literature on mineral luminescence is somewhat bimodal in character. On one hand those mineral structures that have proved useful as phosphors or as crystal lasers have been studied in great detail and the physics of the energy transfer processes are often well known. The luminescence characteristics of many other minerals... 

Electrical Energy Consumption in the Electrochemical Mineralization Process... 

K. E. Haque, Microwave energy for mineral treatment processes, Int. J. Miner. Process, 57,1-24, 1999. 

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