Post on 13-Jan-2017
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USE OF HYDROMETALLURGY IN METAL RECOVERY FROM MINE WASTES
BY : ALI MEHRISUPERVISOR : DR. KARIMI
CONTENT
Introduction Types of mine waste Classification of minerals wastes Mine waste leaching References
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3
Aspects :1. Economical2. Environmental
THE IMPORTANCE OF RECOVERING WASTE[1]
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Creates jobs Growth of an industry Utilize smaller solid waste dumpsters Converting waste materials into new products Reduce the consumption of fresh raw materials
ECONOMICAL ASPECTS
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Resource conservation Reduce energy usage Air pollution, including reductions in greenhouse gas generation Reduce water pollution (from land filling)
ENVIRONMENTAL ASPECTS[2]
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MINERAL EXTRACTION: FROM MINING TO METAL[3]
MiningMineral processing
(beneficiation)
Metallurgical extraction
Mineralconcentrate
Metal
Waste rock
Tailings
Slags
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COMPARISON OF WASTE AND PRODUCT[11]
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Cut – off grade ores
Tailings from mineral products
Residues
TYPES OF MINE WASTE[4][5]
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CLASSIFICATION OF MINERALS WASTES[4]
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WASTE CUT OFF GRADES[6]
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“Acid mine drainage” refers to a particular process whereby low pH
mine water is formed from the oxidation of sulphide minerals
AMD is particularly prevalent in both metallic mineral and coal
mines.
WHAT IS AMD[3]
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PROCESS[7]
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IMPACTS OF AMD
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General equations for this process are: 2FeS2 + 7O2+ 2H2O → 2Fe2+ + 4SO4
2- + 4H+ 4Fe2+ + O2 + 4H+ 4Fe3+ + 2H2O 4Fe3+ + 12H2O 4Fe(OH)3 + 12H+ FeS2 + 14Fe3+ + 8H2O → 15Fe2++ 2SO4
2- + 16H+
WHAT IS AMD[8]
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Aluminum1. Gibbsite2. Bohmite3. Diaspore
MINE WASTE LEACHING[9]
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RED MUD
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50 % of bauxite is red-mud:- a waste-product from the Bayers Process:
Fe2O3: 70 wt. pct. (35-38% metal value) Al2O3: 10 wt. pct. TiO2: 7.0 wt. pct. CaO: 7.5 wt. pct
RED MUD[10]
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RED MUD RECOVERY
Product Note
1) Pyro only
Pig iron,Ti-rich slag
(REE)/Metallic iron
① smelting : Iron oxide Reduction in blast furnace or similar reacto
② solid state reductionDisadvantage• High Na contents in Red Mud: sodium oxide deposition -.• High drying cost of red mud
2) Pyro + HydroPig iron,
REE(from REE slag)
• Pig iron by reluctant, Concentration of REE in slag• Recovery of Concentrated REE by hydro method• High sodium contents and Waste water problem
3) Hydro only REE
• Selective leaching of REE (Fe2O3 is not leached, Using HNO3, Y• 96%, Sc 80%, light lanthanides 30-50%)Selective precipitation and Solvent Extraction
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RECOVERY OF IRON[10]
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RECOVERY OF TITANIUM OXIDE[10]
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SinteringAl2O3
+
Na2CO3
=
2Na
Al
O2
+
CO2(g)Te
mperature
of
operation
:
850-1100oCTi
me
:
2
hours
LeachingNa
Al
O2(s)
=
Na
Al
O2(aq)Te
mperature
of
operation
:
25-100
oCTi
me
:
5-30
m
inutes,
Red
Mud
to
water
:
2-50
gpl
SINTERING AND LEACHING OF ALUMINA[10]
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Copper1. Sandy ore (granular)2. Slimy ore (composed of very fine particles that are difficult to
settle)3. Molybdenite4. Rhenium5. Cobalt
MINE WASTE LEACHING[9]
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SANDY ORE[9]
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SLIMY ORE[9]
• Using sponge iron • Using hydrogen sulfide
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MOLYBDENITE & RHENIUM[9]
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COBALT[9]
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Platinum1. Native platinum ores2. Gold ores3. Nonferrous metals sulfide ores
MINE WASTE LEACHING[9]PtC14 + 2NH4Cl →(NH4)2[PtCl6]
PdC12 + 4NH3 →[Pd(NH3)4]C12
[Pd(NH3)4]C12 + 2HCI → [Pd(NH3)2]C12 + 2NH4C1
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1. Mattias Bäckström. 2007-2013. Compendium of mining and processing waste management technologies
2. https://en.wikipedia.org/wiki/Recycling
3. Mark Muller. 2009. Mine wastes. Pages 3-7
4. CJ Mitchell, DJ Harrison, Dr. HL Robinson, Dr N Ghazireh.2004. minerals from waste. Pages 1-2
5. Pranjit Sharmah. 2013. dumping of mining waste. Pages 5-7
6. S.Najmedin Almasi, Amir Khademian, Reza Yarahmadi. 2015. Determination of Leaching Cutoff Grade Using. Page 1279
REFERENCES
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7. Mark Muller. 2009. Environmental and Social Concerns. Pages 3-4
8. V.GOUTHAM. 2011. Treatment methods of acid mine drainage and a case study on selective recovery of metals. Page 3
9. Fathi Habashi. 1999. Hydrometallurgy. Pages 242-252 & 229-233
10. Brajendra Mishra. 2015. Bauxite Residue Valorisation and Best Practices. Pages 3-28
11. https://www.ausimmbulletin.com/feature/towards-zero-waste/
REFERENCES