Friday 29 December 2017

CLASSIFICATION OF MINERALS ON THE ELECTRICAL PROPERTIES

Ph. D. Natalia Petrovskaya, 2016 Classification of minerals on the electrical properties

Classification of minerals on the electrical properties:
  • Conductors are minerals with high conductivity.
  • Semiconductors are minerals that have an average (low) conductivity.
  • Non-conductors (dielectrics) are minerals that don't conduct electricity.
Conductores: Anthracite, argentite, arsenopyrite, bornite, braunite, cassiterite (ferriferous), chalcocite, chalcopyrite, cobaltite, columbite, copper, covellite, chromite, enargite, galena, gold, graphite, hematite,  ilmenite, magnetite, manganite, marcasite, molibdenite, pyrite, pyrolusite, pyrrhotite, rutile, silver, smaltite, titanomagnetite, wolframite.

Semiconductors: bauxite, cassiterite, cuprite, limonite, magnesite, siderite, sphalerite,  vermiculite

Non-conductors: Actinolite, albite, almandite, andesite, anglesite, anhydrite, apatite, azurite, barite, beryl, biotite, calcite, celestite, cerussite, chrome, chrisocolla, chlorite, corundum, crocidolite, crocoite, chromite, cryolite, diamond, diaspore, diopside, dolomite, enstatite, epidote, feldspar, fluorite, franklinite, gibbsite, quartz, halite, monazite, muscovite, phlogopite, scheelite, spinel, spodumene, staurolite, stibnite, stibnite, sylvite, talc, titanite, topaz, tourmaline, wollastonite, wulfenite, xenotime, zircon.

It is easy to separate conductors out of non-conductors. It is more complicated to separate semiconductors out of conductors or non-conductors.

The electrical separation is very useful for separate next minerals:
  • Gold and platinum
  • Diamond and rock minerals
  • Ilmenite and apatite, garnet, tourmaline, zircon
  • Cassiterite and monazite, zircon, scheelite, spodumene
  • Rutil and  monazite, zircon
  • Monazite and  cassiterite, columbite, rutil
The electrical separation is used for:
  • Separation of placer deposits of rare earth minerals
  • Separation of tin and tungsten ores
  • Separation of ferrous metals ores
  • Separation of non-metallic minerals:  quartz, feldspar, coal, mica
  • Secondary metals: non-ferrous and ferrous metals, solid waste
  • Dedusting and dust collection
  • Separation of materials by size: building materials, ores
 
There are 6 types of electrical separation of minerals:
  • Electrical separation
  • Electrostatic separation
  • Dielectric separation
  • Tribo-electrostatic separation
  • Tribo adhesive separation
  • Separation in the corona–discharge field
Rare types of electrical separation of minerals:
  • Electrical classification by size and shape
  • Pyroelectric separation
  • Tribo-aero-electrostatic separation
  • Pneumoelectric separation
  • Fluidising-electrostatic separation
  • Crown-magnetic separation
  • Opto-electrical separation
Electrical separation is used frequently with magnetic separation and gravity separation. Flotation can be used for eliminate silycates out of the iron concentrate.
Next effects exist in nature:
  • Thermoelectric effect
  • Pyroelectric effect
  • Photoconductivity
  • Photo-electromotive-force effect (EMF)
  • Photoluminescence
  • Piezoelectric effect
  • Triboelectric effect
  • Triboluminescence

  • Electrostatic separators
  • Corona-electrostatic separators
  • Tribo-electrostatic separators
  • Tribo adhesive separators (TAS)
  • Dielectric separators
  • Electrostatic classifiers

HOW TO CHOOSE A METHOD FOR THE SEPARATION OF MINERALS


Ph.D. Natalia Petrovskaya, February 3, 2016
By

No comments:

Post a Comment

Subscribe to: Post Comments (Atom)