ways to improve ore extraction
TRANSCRIPT
WAYS TO IMPROVE ORE
EXTRACTION
Indirect carbothermic reduction
can be carried out using carbon and Al2O3,
which forms an intermediate Al4C3 and this can further yield aluminium metal at a temperature of 1900–2000 °C.
it requires less energy and yields less CO2 than the Hall-Héroult process.
Aluminium
Calcination
The fire burns on the grate at (G), and the
flames, passing over the bridge at (E), are
deflected down ward by the low sloping
roof of the furnace, and pass directly over
the surface of the charge in the bed of the
furnace at (B), finally escaping through
the throat (F) into the chimney.
Can change alumina to aluminium.
Using less energy than molten electrolyte
process.
Cont..
The aluminum trichlorid precipitate is purified by dissolution and re-precipitation. The final product is calcined to form alumina
the alumina so produced has a higher purity than alumina produced from bauxite by the Bayer process.
Cont..
Fusion methodpowdered silicate mineral is fused with CaCO3 and the fused mass is extracted with HCl and filtered.The filtrate contains chlorides Li, Al, Ca, Na and K whereas silicon is removed as insoluble residue.The filtrate is evaporated to dryness and the residue is extracted with pyridine in which only LiCl dissolves.Pyridine is distilled off while LiCl is left behind.
Lithium
LiCl then undergoes the electrolysis prosess to obtain pure lithium metals.
LiCI++ ↑ Li+ + CI-
At cathode: Li+ + e- → Li
At anode : 2CI- - 2e- → CI2
Lithium extraction can be improve by adding new method.
analytical Methods
The pegmatite rocks as well as the mineral products were analyzed by chemical (ICP-OES and XRF), optical and mineralogical analysis (XRD).
Electrodynamic FragmentationThe introduction of a electrodynamicfragmentation process allows the selective liberation of pegmatite minerals via high voltage pulses.
During electrodynamic fragmentation shock waves travel through a solid submerged in water.
The high selectivity of the fragmentation is achieved through high tensile stress in the areas of grain boundaries, inclusions or composite interfaces, causing the material to predominantly break at these boundaries.
A: Polished section of a typical pegmatite piece. B: spodumene crystalsseparated after electrodynamicfragmentation. C: feldspar crystals separated after electrodynamicfragmentation; D: quartz crystals separated after electrodynamicfragmentation.
A B C D
Increase the variety of final product.
Decreasing the usage of energy to grind material that are not needed.