glossary - technology - multotec · minerals engineering ... or very fine ferrosilicon in water for...
TRANSCRIPT
GLOSSARY - TECHNOLOGY
www.multotec.com
Slide: 2 www.multotec.com
Metallurgy
The science of ore processing and metals
Slide: 3 www.multotec.com
Minerals Engineering
The first major step in extracting metals. Involves the
separation and concentration of minerals from ores using
mainly physical processes.
Often referred to as
Mineral Dressing or Ore Dressing.
Slide: 4 www.multotec.com
Extractive Metallurgy
Follows Ore Dressing.
Includes Pyrometallurgy, Hydrometallurgy, Electrometallurgy
for:
• the removal of remaining waste,
• the decomposition of the metallic mineral to produce metal
• the subsequent refining of metal.
Slide: 5 www.multotec.com
Hydrometallurgy
Uses liquid chemical solutions, treated resins and organics to
separate and concentrate metals by processes such as acid,
alkaline and pressure leaching, ion exchange, solvent
extraction, molecular recognition, precipitation,
crystallization.
Slide: 6 www.multotec.com
Pyrometallurgy
Uses high temperatures for smelting and refining reactions
and melting, pouring, casting and solidification processes.
Pyrometallurgy involves removing impurities from metals by
introducing air and fluxes into the molten metal. The
impurities are removed as gases or slag.
Slide: 7 www.multotec.com
Electrometallurgy Uses electrical energy, principally for electrolysis or
electrowinning to extract and refine metals.
Slide: 8 www.multotec.com
Beneficiation
Treatment of a crude ore in order to improve it’s quality.
Example: beneficiating raw coal to a steam coal for power
generation or to a coking coal for furnaces.
Slide: 9 www.multotec.com
Freeing of valuable minerals /
metals in an ore or mineral by
crushing and grinding.
Liberation
Well Liberated Minerals
Poorly Liberated Minerals
Slide: 10 www.multotec.com
Plant
Facility for processing ores or gravels. A plant where ore is
milled, usually to fine powder, and the valuable metals are
extracted by physical and/or chemical processes.
Slide: 11 www.multotec.com
Run-of-Mine Ore
Uncrushed ore in its natural state just as it is when blasted.
Ore, as accepted for treatment from the Mine.
Slide: 12 www.multotec.com
Gangue
Waste rock that surrounds an ore deposit.
The waste material in an ore.
The valueless tailings/waste fraction of an ore rejected by a
separating process.
Slide: 13 www.multotec.com
Feedrate / Throughput
Capacity of any section of a Plant in terms of tons treated in
a given period e.g. tons per hour for coal, tons per month for
gold.
Slide: 14 www.multotec.com
Recovery
Indicates the proportion of valuable material acquired
from the processing of an ore.
Generally stated as a percentage of the values recovered
compared to the total values present.
Slide: 15 www.multotec.com
Tailings
The neutralised waste discarded after the economically
recoverable metals have been extracted from the ore.
Slide: 16 www.multotec.com
TECHNOLOGIES
Slide: 17 www.multotec.com
How to extract the needle from the haystack
Slide: 18 www.multotec.com
Metallurgical Approaches
Minerals Processing Engineer: Run the entire haystack
through a magnet to retrieve the needle
Pyrometallurgist: Burn the haystack down to find the needle
in the ashes
Hydrometallurgist: Chop up haystack, dissolve it all with
chemicals, plate out metal of the needle
Slide: 19 www.multotec.com
Mineral Product
Metal Product
Run-of-Mine Ore
PREPARATION & SIZING
MINERALS SEPARATION
METALS EXTRACTION
METALS PURIFICATION
METAL PRODUCTION
Slide: 20 www.multotec.com
Minerals Engineering
The first major step in the extraction of metals, this involves
the separation and concentration of minerals from ores using
primarily physical processes.
Often referred to as
Mineral Dressing or Ore Dressing.
Slide: 21 www.multotec.com
Screening
Sizing separation of ore particles into defined size ranges
(fractions).
Slide: 22 www.multotec.com
Gravity Separation
Recovery of values from crushed rock or gravel using
specific gravity differences to separate them.
Slide: 23 www.multotec.com
Jigging
The vertical pulsing of a mass of particles dry, or in water, to
assist the separation of heavy and light ore particles.
Equipment for recovering heavy minerals by gravity settling
through a vibrating screen covered with a ragging bed.
Jig
Slide: 24 www.multotec.com
DMS
Dense Media Separation, in which lighter density ore
particles (floats) separate from heavier particles (sinks) in an
artificial or organic liquid (medium) of intermediate density.
Industrially, the medium is very fine magnetite mixed in
water for coal separations or very fine ferrosilicon in water for
higher density operations such as for diamonds, iron ore,
chromites, manganese ores.
Slide: 25 www.multotec.com
Magnetic Separator
Uses a strong permanent or electro-magnetic field to extract
ferro-magnetic materials from para-magnetic or dia-magnetic
sands or concentrates.
Slide: 26 www.multotec.com
Comminution
Particle size reduction, the crushing of coarse ore
or grinding/milling of fine ore by impact, abrasion, attrition or
compression.
Slide: 27 www.multotec.com
Autogenous Milling
In milling, selectively sized lumps of ore are used as the
grinding media.
Slide: 28 www.multotec.com
Semi-Autogenous Milling (SAG)
Grinding/milling of rock to fine powder in which the grinding
media (charge) consists of larger pieces of rock and steel
balls.
Slide: 29 www.multotec.com
A steel cylinder loaded with
steel balls into which crushed
ore is fed.
The ball mill is rotated, causing
the balls to roll and fall and
grind the ore.
Ball Mill
Slide: 30 www.multotec.com
Cyclone
Hydrocyclone: a centrifugal classifier continuously
separating particles in a water slurry on their size, shape and
density characteristics.
Dense Media Cyclone: a similar vessel with critical
differences which uses an artificial high density medium to
assist density separation.
Slide: 31 www.multotec.com
Flotation
A process for concentrating minerals in milled ores, which
uses the selective adhesion of certain minerals to air bubbles
in water after treatment with chemicals.
The right chemicals with air are added to a stirred ground ore
slurry so the minerals will float to the surface. The metal-rich
flotation concentrate is then skimmed off the surface.
Slide: 32 www.multotec.com
Electrostatic Separator
Separates mineral particles according to retained static
electrical charges induced on them by a high voltage field
with the heavy mineral concentrates deflected by an
electrode.
Slide: 33 www.multotec.com
Thickener
A high capacity solid/liquid separation device. A large circular
tank, often fitted with moving rakes, in which solids settle
slowly to form a high density slurry for continuous removal
from below, while clear water overflows the tank.
Slide: 34 www.multotec.com
Extractive Metallurgy
Follows Minerals Engineering/Ore Dressing.
Includes Pyrometallurgy, Hydrometallurgy, Electrometallurgy
for:
• the removal of any remaining waste,
• the decomposition of the metallic mineral to produce a
metal
• the subsequent refining of the metal.
www.multotec.com