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| − | '''Mineral processing''', otherwise known as mineral dressing, is the practice of beneficiating valuable minerals from their [[ore]]s.
| + | {{honor_header|3|1949|Nature<br>General Conference<br>2001 Edition}} |
| − | Industrial mineral treatment processes usually combine a number of unit operations in order to liberate and separate minerals by exploiting the differences in physical properties of the different minerals that make up an ore.
| + | ==1. Have the Rocks and Minerals Honor == |
| | + | {{ay prerequisite|Nature|Rocks & Minerals}} |
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| − | Many plants also incorporate hydrometallurgical or pyrometallurgical processes as part of an extractive metallurgical operation.
| + | ==2. Have a collection of 30 rocks and minerals properly named, 20 of which you have personally collected. Label with collector's name, date and locality in which it was found. == |
| − | | + | ==3. Know two minerals that belong to each of the following crystal systems:== |
| − | Mineral processing involves four general types of operations: '''Comminution''' or particle size reduction, '''Sizing''' or separation of particle sizes by screening or classification, '''Concentration''' by taking advantage of physical and surface chemical properties, and '''Dewatering''' or solid/liquid separation.
| + | ===a. Isometric === |
| − | | + | ===b. Hexagonal === |
| − | A number of auxiliary [[materials handling]] operations are also considered a branch of mineral processing such as storage (as in bin design), conveying, sampling, weighing, slurry transport, and pneumatic transport.
| + | ===c. Tetragonal === |
| − | | + | ==4. Know Mohs' scale of hardness and the simplified field tests of hardness. By using these field tests, collect a scale range of specimens from your own region to form your own hardness test set. == |
| − | == Comminution == | + | ==5. Do one of the following:== |
| − | [[Comminution]] is particle size reduction of materials. Comminution may be carried out on either dry materials or slurries. [[Crushing]] and [[grinding]] are the two primary comminution processes. Crushing is normally carried out on "run-of-mine" ore, while grinding (normally carried out after crushing) may be conducted on dry or slurried material.
| + | ===a. Know and tell two different processes by which metals are extracted from ores.=== |
| − | | + | ===b. Know eight minerals and tell how each is used. === |
| − | == Sizing == | + | ==6. Define the following: == |
| − | Sizing is the general term for separation of particles according to size.
| + | ===a. Crystalline === |
| − | | + | ===b. Cryptocrystalline === |
| − | The simplest of sizing processes is screening, or passing the particles to be sized through a screen or number of screens. Screening equipment can include grizzlies, bar screens, and wire mesh screens. Screens can be static (typically the case for very coarse material), or they can incorporate mechanisms to shake or vibrate the screen.
| + | ===c. Breccia === |
| − | | + | ===d. Noncrystalline === |
| − | Classification refers to sizing operations that exploits the differences in settling velocities exhibited by particles of different size. Classification equipment may include [[ore sorters]], gas cyclones, hydrocyclones, rake classifiers, rotating trommels, or fluidized classifers. When the feed material contains particles of different densities as well as particles of different size, a degree of concentration takes place during classification because settling velocities are also dependent on particle density.
| + | ===e. Fibrous fracture === |
| − | | + | ===f. Vitreous luster === |
| − | == Froth flotation == | + | ===g. Geode === |
| − | [[Froth flotation]] is achieved when particles are separated based on their surface potential. Hydrophobic particles are recovered to the froth, whereas hydrophilic particles are discharged with the tailings stream. Some mineral particles are naturally hydrophobic, whereas others require specific reagent additions to change their surface potentials.[[Oxide]] ores, such as [[spodumene]] and [[tantalite]] can be treated using [[oxalic acid]] based collectors. [[Sulfide]] ores can be recovered using xanthate or dithiophosphate type collectors.
| + | ===h. Petrification === |
| − | | + | ===i. Stalactite=== |
| − | == Gravity concentration == | + | ===j. Fluorescence === |
| − | Particles can be classified based on their [[specific gravity]]. Gravity concentration processes include:
| + | ==7. What four metals are frequently found in native or free form? == |
| − | * Heavy media or dense media separation
| + | ==8. Discuss the content of three statements from the writings of Ellen G. White concerning rocks or mine== |
| − | * Shaking tables, such as the wilfely table
| + | ==References== |
| − | * Spirals
| + | [[Category:Adventist Youth Honors Answer Book|{{SUBPAGENAME}}]] |
| − | * Centrifugal bowl concentrators
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| − | * Jig concentrators. [http://www.gekkos.com Gekko Systems] is a manufacturer of the InLine Pressure Jig (IPJ), a continuous processing gravity concentration device.
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| − | # Multi gravity separators
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| − | # Nelson concentrators
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| − | == Electrostatic separation == | |
| − | Non-conducting particles maintain an electrostatic charge induced electrically, and so remain pinned to a charged drum. Conducting particles do not maintain the electrostatic charge and so fall off the drum, thus minerals such as [[ilmenite]] and [[rutile]] can be separated.
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| − | | |
| − | == Magnetic separation == | |
| − | Minerals such as [[magnetite]] and [[pyrrhotite]] are naturally [[magnetic]], and so can be separated from non-magnetic particles using strong magnets.
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| − | == External links == | |
| − | *[http://www.tandf.co.uk/journals/titles/08827508.asp Mineral Processing and Extractive Metallurgy Review]
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| − | *[http://www.min-eng.com/ Minerals Engineering International]
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| − | [[Category:Metallurgy]] | |
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| − | [[fi:Rikastus]]
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