9-early magmatic & nickel laterite deposit
Post on 18-Feb-2018
257 Views
Preview:
TRANSCRIPT
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 1/79
P.T. INCO
NICKEL LATERITES
Formation & Mineralogy,Exploration, Mining, and
Processing Method
March 2006
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 2/79
P.T. INCO
NICKEL LATERITES FORMATION
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 3/79
P.T. INCO WHAT ARE NICKEL LATERITES?
• Nickel laterites are residual soils that have developed
over ultramafic rocks through processes of chemical
weathering and supergene enrichment
•Critical conditions for the formation of nickel laterites:
Appropriate accumulation of soil
Appropriate rock type
Appropriate weathering conditions Appropriate conditions for supergene enrichment
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 4/79
P.T. INCO TYPICAL LATERITE PROFILE
Red Laterite
Limonitezone
Saprolitezone
Bedrock pinnacle
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 5/79
P.T. INCO APPROACH TO LATERITE STUDY
• Study of Laterites requires a good knowledge of the
relevant principles of:
Chemistry
Mineralogy
Petrology
Geomorphology
Soil formation
Processing constraints & technology
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 6/79
P.T. INCO
MINERALOGY
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 7/79
P.T. INCO MINERALS ASSOCIATED WITH LATERITES
Primaryigneous
minerals
OlivinePyroxene
MagnetiteChromite
Mafics Spinels
Hydrothermal
minerals
Serpentine
Talc
Chlorite
Laterite
weathering
minerals
Oxides &
Hydroxides
Hematite
Goethite
Limonite
BauxiteGibbsite
Secondary:
Serpentine
Talc
Chlorite
Nickel
Silicates
Garnierites:
Nepouite
Willemsite
PimelliteNimite
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 8/79
P.T. INCO LATERITE MINERAL ASSOCIATIONS
H2O
MgO FeO
SiO2
Fe2O3H2O
Fo
Fa
En
Fs
Serp.
Talc
Magnesioferrite
Hematite
Magnetite
GoethiteLimonite
Xanthosiderite
Esmeraldaite
OLIV
PYXChlor.
Brucite
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 9/79
P.T. INCO OLIVINES — Formation
• Forsterite crystallises first (higher melting temperature)
• If the olivine is allowed to react with the liquid magma, it
will change its composition towards ferrous olivine
• As the larger ferrous cations replace the smaller Mg
cations, the melting temperature is progressively
reduced
• If the original magma has more silica than can be used
by the olivines (> 40%), then the more sil iceous mafic
minerals such as pyroxenes will be formed
• Olivines can take up to 0.5% of NiO (0.4% Ni)
• Ni occurs as replacement of Mg atoms by Ni atoms
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 10/79
P.T. INCO OLIVINES — Formation
MAGMAForsterite forms first
High melting temp.
Crystals
settle on
the bottomof magma
chamber.
Original
Forsteritecomposition
preserved
Crystals
allowed to
react withmagma
Magma with < 40% SiO2
Only olivine forms. Successivecrystals richer in Fayalite.
Magma with > 40% SiO2
Pyroxenes form, depending onsil ica availabili ty.
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 11/79
P.T. INCO ALTERATION OF OLIVINE
MgO SiO2
H2O
Fo En
Talc
Serpentine
Alteration of Forsterite
+800°C: Fo to En
625-800°C: Fo to En to Talc
500-625°C: Fo to Talc200-500°C: Fo to Serpentine
Hydrothermal
Magmatic
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 12/79
P.T. INCO GARNIERITE GROUP
SiO2
MgO NiO
Kerolite - Talc
Serpentine Pimelite
Nepouite
7°A basal
spacing
GARNIERITES
Mg3Si4O10(OH)2.nH2O
Mg3Si2O5(OH)4
Ni3Si4O10(OH)2.H2O
Ni3Si2O5(OH)4
10°A basal
spacing
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 13/79
P.T. INCO WORLD’S SERPENTINE BELTS
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 14/79
P.T. INCO STRUCTURE OF OCEANIC CRUST
Marine Sediments
Ocean basalts
Mantle Peridotites
Layer
Seismic
Velocity
1 2.0 km/sec
2 5.1 km/sec
3 6.7 km/sec
4 8.1 km/sec
Thickness
0 – 4 km
1 – 2.5 km
5 km
0.5 km
O c e ani c C r u s t
5 – 8 k m
Sea Level
8.1 km/sec
Metamorphic
Grade
Zeolite
Greenschist
Amphibolite
Mohorovicic
Discontinuity
Layered Peridotite
Gabbros
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 15/79
P.T. INCO Ni IN ULTRAMAFIC ROCKS
• Ni in ultramafic rocks is primarily in mafic minerals
High in olivines (0.2 – 0.3% Ni)
Low in orthopyroxenes (0.05 – 0.1% Ni) Very low in clinopyroxenes (< 0.05% Ni)
• Thus, decrease in the olivine content of the ultramafic reduces the
overall nickel content of the rock:
Highest Ni grades in dunites Lower Ni grades in peridotites
Lowest Ni grades in pyroxenites
• Ni in mafic minerals is largely as a replacement of Mg
• Some Ni may exist as replacement of the larger Fe atoms
• Primary chromite and magnetite may contain minor Ni
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 16/79
P.T. INCO WEATHERING
Four major processes under which rocks change their physical or
chemical properties:
Melting (at very high temperatures)
Metamorphism (high temperatures / pressure / addition)
Hydrothermal alteration (through high-temperature fluids)
Weathering (at ordinary temperatures and pressure)
Types of weathering:
Physical (mechanical breakdown of rocks) erosion, thermal expansion/contraction, action of plants
Chemical (breakdown of rocks through chemical processes)
contact with water, oxygen, carbon dioxide, etc.
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 17/79
P.T. INCO CHEMICAL WEATHERING
“ The process in which rocks react to atmospheric, hydrospheric and
biologic agencies to produce mineral phases that are more stable”
1. HydrolysisOxygen, carbon dioxide, ground water, dissolved acids attack the
minerals in the rock
2. Oxidation
Elements released by chemical weathering are oxidised
3. Hydration
Reaction with water adds the hydroxyl ion to newly formed minerals
4. Solution
The more soluble products of weathering are dissolved and removed
And the cycle continues .....
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 18/79
P.T. INCO CONDITIONS FOR CHEMICAL WEATHERING
RAIN AND THUNDER STORMS
Nitrous oxides, CO2
HUMOUS (Organic) LAYER
WATER TABLE
ZONE OF OXIDATION
(Reducing conditions)
(Reducing conditions)
Acidic
Rain
Acidic
Rain
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 19/79
P.T. INCO Elemental Mobilit ies
• Many metallic elements are soluble in
ground waters
• Solubil ities generally increase withtemperature
• Solubil ities are a function of pH (acidity)
and Eh (redox) conditions
Mobilit ies of elements found in ultramafic
rocks are generally classified as:
• Highly soluble = Ca, Na, Mg, K, Si
• Non-soluble = Al, Fe+++, Cr, Ti, Mn, Co
• Variably soluble = Ni, Fe++
Relative
Mobilities
(decreasingOrder)
Ca++ = 3.0
Na+ = 2.4
Mg++ = 1.3
K+ = 1.25
SiO2 = 0.20
Fe2O3 = 0.04
Al2O
3= 0.02
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 20/79
P.T. INCO
The following factors influence the speed as well as the character of
chemical weathering:
1. Stability of Minerals (crystal structure, melting points)
2. Acidity / basicity (pH) conditions
3. Reduction / oxidation (redox potential) of the environment
4. Rate of removal of dissolved constituents
5. Climate (temperature, rainfall, fluctuation of water table)
6. Topography
7. Rock conditions (Fracturing, Jointing, Grain size)
Factors Influencing Chemical Weathering
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 21/79
P.T. INCO Various topographic profiles
Steep Hill
Depression / basin
Gentle Hill
Plateau
River Terrace
Dissected Plateau
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 22/79
P.T. INCO Role of Water Table
• The position of water table depends on:
Amount of rainfall
Ground porosity/permeability Topographic characteristics
• Impact of High water tableMuch of rock fil led with water
Less oxygen being supplied
• Fluctuating water table
Varying zones of oxidation and reduction
Frequent flushing of system to remove dissolved material
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 23/79
P.T. INCO
WEATHERING OF
ULTRAMAFIC ROCKS AND LATERITES
Weathering of Ultramafic rocks
Behaviour of MgO, SiO2, Fe, Al, Ni
Laterite Profile: Limonite zone
Laterite Profile: Intermediate zone
Laterite Profile: Saprolite zone
Rates of Laterisation
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 24/79
P.T. INCO WEATHERING OF OLIVINE
Forsterite: 2MgO.SiO2 (MgO = 57.3%)
• Highly unstable in weathering
environment
• Individual SiO4 tetrahedra are
weakly bonded by cations
•Magnesia is highly soluble in ground water
• Release of magnesia breaks down the Olivine structure
• Breakdown of Olivines releases various cations:
MgO, FeO, NiO, MnO
Sorowako Olivine:
• FeO = 9.0%
• Al2O3 = 0.4%
• NiO = 0.37%
• MnO = 0.12%
• Cr 2O3 = 0.02%
• TiO2 = 0.02%
Replacements
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 25/79
P.T. INCO WEATHERING OF PYROXENE
Enstatite: MgO.SiO2 (MgO = 40.2%)
• Relatively unstable in weathering
environment (but < Olivine)
• Individual SiO4 tetrahedra arebonded by shared Oxygen
• Magnesia is highly soluble in
ground water • Release of magnesia breaks down the Pyroxene
• Breakdown of Pyroxenes releases various cations:
MgO, FeO, CaO.Al2O3.NiO, MnO
Sorowako Pyroxene:
Opx Cpx
• FeO = 6.0 2.5
• Al2O3 = 3.2 3.5
• CaO = 1.9 21.7
• NiO = 0.08 0.05
• MnO = 0.13 0.08
• Cr 2O3 = 0.58 0.86
• TiO2 = 0.05 0.09
Replacements
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 26/79
P.T. INCO Weathering of Serpentine
• Serpentine: 3MgO.2SiO2.2H2O
• Magnesia is leached out first, leaving behind a silica
enriched phase or montmorillonite and chlorite
• Ni and Fe can replace the magnesium being leached.
This results in the formation of:
Iron containing serpentine
Nickeliferous serpentine
• Through a similar process, nickel is also fixed in Talc,Chlorite, and Smectite
• Eventually, montmorillonite and chlorite also break
down, releasing remaining magnesia and sil ica
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 27/79
P.T. INCO Behaviour of Magnesia (MgO)
• Magnesia is present in Olivine, Pyroxene and Serpentine
•Magnesia is released by the breakdown of olivines
• Magnesia has very high solubility in ground water
• It is the first major component to be leached out in large
quantities
• Some magnesia may stay in the laterite profile to form
clay minerals and nickel hydrosil icates
• Final product of lateritic weathering (Goethite/limonite)
does not contain any magnesia
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 28/79
P.T. INCO Behaviour of Silica (SiO2)
• Silica is present in Olivine, Pyroxene and Serpentine
• Silica is released by the breakdown of ferro-magnesian
silicates
• In humid environments, laterite is constantly flushed and
lit tle silica gets f ixed as smectite/nontronite clays
• In wet-dry environments, flushing of laterite profile is
poor and si lica gets fixed as smectite/nontronite clays in
the Intermediate Zone• In the alkaline environment (where MgO is being
released), silica can precipitate from solution as
amorphous silica (sil ica veins, boxwork, coatings)
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 29/79
P.T. INCO Behaviour of Iron (Fe)
• Iron is present as: Ferrous Ferric
In olivine (MgO.FeO.SiO2) : Fe++
In pyroxene (MgO.FeO.2SiO2) : Fe++
In chromite (FeO.Cr 2O
3) : Fe++
In ilmenite (FeO.TiO2) : Fe++
In magnetite (FeO.Fe2O3) : Fe++ Fe+++
• Breakdown of mafic minerals releases Ferrous ions
• Ferrous ion is quite soluble and mobile
• Ferrous ions get quickly oxidised to ferric ions, as:
Hematite / Maghemite, Goethite, Limonite
• Iron in primary magnetite and ilmenite oxidise to form:
Hematite / Maghemite, Goethite, Limonite
• Iron in the Ferric (Fe+++) state is very insoluble
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 30/79
P.T. INCO Behaviour of Alumina
• Alumina is present in:
Pyroxenes (as impurity and as solid solution)
Common Spinel (MgO.Al2O3)
• On the breakdown of pyroxenes, alumina is temporarily
fixed in the chlorites (Clinochlore: 5MgO.Al2O3.3SiO2.4H2O)
• After the breakdown of chlorites, alumina is fixed in
gibbsite (Al2O3.3H2O)
• Alumina is very insoluble in ground water in the pH
range commonly found (4 – 9)
• Al+++
and Fe+++
are truly residual elements in laterites
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 31/79
P.T. INCO Behaviour of Mn and Co
• Minor amounts of Mn and Co are present in the mafic
minerals (Olivine and Pyroxene)
• On the breakdown of mafic minerals, Mn and Co are
released
•Mn and Co are slightly soluble in acidic waters at the top
of the laterite profile
• Mn and Co are very insoluble in alkaline waters
• Mn and Co concentrate at the bottom of the LimoniteZone
• Much of Cobalt is t ied to the manganese wad
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 32/79
P.T. INCO Behaviour of Ni
• Minor Ni is present in Olivines (0.3%), Orthopyroxenes
(0.1%), and Clinopyroxenes (< 0.05%)
• Ni can replace the Mg being leached out of serpentines,Talcs and Chlorite to form nickeliferous silicates
• Ni is soluble in acidic water but insoluble in alkaline
water
• Ni travels down the profi le and gets precipitated as Ni
hydrosilicates in the Saprolite Zone (alkaline environment,
where solubili ty of Mg is higher than that of Ni)
• Some Ni gets permanently t ied to the goethite structure(as solid solution, from 0.5 to 1.5% Ni)
• Ni is also tied to Asbolite / Manganese wad at the base of
the Limonite Zone
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 33/79
P.T. INCO LATERITES
• The term “ Laterite” is derived from the Latin word “ later ” whichmeans brick
• Buchanan Hamilton first introduced the term in 1807 to the earthy
iron crusts that were being cut into bricks by the people of south-
central India
• Currently, the term Laterite is used for soils that are rich in
sesquioxides of iron and aluminium, formed under the influence of
chemical weathering with special ground water conditions
• Development of laterites require:
Availability of appropriate rocks that contain iron and aluminium
Relatively high temperatures (to aid chemical attack)
High rainfall (to aid chemical weathering)
Intense leaching (to remove mobile elements)
Strongly oxidising environment (to make sesquioxides)
Gentle topography (to preserve the laterite once it is formed)
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 34/79
P.T. INCO LATERITE PROFILE
“Red” Hematite
“Yellow” Limonite
Saprolite zone
Bedrock zone
• Acidic environment• Collapsed profile•“Soluble” ions leached (Ca, Mg, Si, Na, K)• “Insoluble” ions concentrated (Cr, Al, Fe)
• Mn, Co show supergene enrichment
• Alkaline environment• Un-collapsed profile• Leaching / residual concentration in progress• Boulder formation• Ni shows supergene enrichment
• Alkaline environment• Joints / fractures exposed to U/G water • Chemical attack is just beginning
• Channelways provide removal of dissolveds
Laterite Zones Processes at work
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 35/79
P.T. INCO LATERITE PROFILE – Limonite zone
• The uppermost zone is rich in hematite and goethite
• The limonite may be remobilised in near-surface acid conditions and
crystallised to hard ferricrete/iron cap
• Extremely insoluble minerals may persist in this zone (spinel,
magnetite, primary talc)
• The base of the limonite zone is enriched in manganese, cobalt and
nickel (manganese wad). This wad occurs as coatings on joints and
fracture planes
• Limonite zone represents laterite that has collapsed
• The dry bulk density in the limonite zone is higher than in the
Transition zone
• Due to collapse, the original texture and structure of rock is
completely obli terated
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 36/79
P.T. INCO
• Contains soft Smectite clays – usually nontronite (Fe2O3.2SiO2.2H2O)
– and hard crystalline quartz
• Leaching is advanced but collapse is not complete
(resulting in low bulk density)
• Some original texture/structure is still preserved
• The formation of dist inct intermediate zone requires wet-dry cl imate
• If the Intermediate Zone is developed, the occurrence of manganese
wad is more prominent in the upper part of the Intermediate Zone
rather than in the lower part of the Limonite Zone
LATERITE PROFILE – Intermediate zone
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 37/79
P.T. INCO
• The Zone consists of: bedrock fragments, saprolised rims of
boulders, precipitated quartz, and garnierite
• Chemical weathering is proceeding along joints & cracks
• Saprolisation along joints leads to the formation of “ boulders”
• The boulders can have a significant saprolised crust
• Original rock texture and structure are well preserved
• Most parent rock minerals are preserved
• In Unserpentinised rock, saprolisation is limited to boulder surfaces
since the rock is very hard (boulders are free of replacement nickel)
• In serpentinised rock, saprolisation proceeds through much of the
rock mass since it is soft (boulders may contain significant
quantities of replacement nickel)
LATERITE PROFILE – Saprolite zone
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 38/79
P.T. INCO SOROWAKO LATERITE PROFILE
0
5
10
15
20
DEPTH (m)
WEST BLOCK
UNSERPENTINISED
EAST BLOCK
SERPENTINISED
Limonite
Overburden
Iron cap
Limonite ore
Saprolite Ore
Bedrock
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 39/79
P.T. INCO NICKEL LATERITE PROFILES
0
20
40
DEPTH (m)
SILICATE
(eg New Caledonia)
CLAY
(eg Murrin Murr in)
OXIDE
(eg Moa Bay)
Cuirasse
Red
limonite
Yellow
limonite
Earthy
ore
Ore with
boulders
Rocky
ore
Bedrock Bedrock
Saprolite
(Serpentine,
chlorite,
smectite)
Smectite
zone
Ferruginous
zone
Colluvium
Bedrock
Saprolite
Limonite
Limoniteoverburden
Iron cap
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 40/79
P.T. INCO Major Elements in Laterite Profile
0
5
10
15
20
25
30
35
40
45
50
-6 -4 -2 0 2 4 6 8 10 12 14
DEPTH IN METRES
P E R C E
N T A G E
S
T r a n s i t i o n z o n e
FeSiO2
AlO2O3
MgO
LIMONITE SAPROLITE
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 41/79
P.T. INCO Minor Elements in Laterite Profile
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
-6 -4 -2 0 2 4 6 8 10 12 14
DEPTH IN METRES
P E R C E
N T A G E
S
r a
n s
o n z o n e
Cr 2O3
MnO
Co
Ni
Supergene Ni
enrichment
LIMONITE SAPROLITE
CO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 42/79
P.T. INCO RATES OF LATERISATION
1
10
100
1,000
10,000
100,000
1 1 0 1 0 0
1 , 0 0 0
1 0 , 0
0 0
1 0 0 , 0
0 0
1 , 0 0 0 , 0
0 0
1 0 , 0
0 0 , 0
0 0
TIME IN YEARS
m
m
o f L a t e r i t e
1 metre
10 metres
100 metres
Based on mineralsolubilities in the
Laboratory
Based on water
compositions of
well-drainedUltramafics
P T INCO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 43/79
P.T. INCO USE OF Ni IN THE INDUSTRY
• Over 60% of the world’s nickel is used for making
stainless steel
• With the addition of nickel in steel, it is made resistant tocorrosion
• Nickel is also used in making superalloys that can
withstand high temperatures and pressures (also high
electrical conductivity)
• Nickel is also used for plating, making coins, Ni-Cd and
Ni-metalhydride batteries, and as a chemical catalyst
• Cobalt has properties similar to nickel but is moreexpensive
• Primary nickel supply comes from newly mined ores
• Secondary nickel supply comes from recycling scrap
P T INCO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 44/79
P.T. INCO
NICKEL LATERITE EXPLORATION
P T INCO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 45/79
P.T. INCO
Nickel Laterite Exploration Stages
• Outlining of ultramafic area
• Outlining and analysis of structural lineaments• Outlining of favourable laterite landforms
• Reconnaissance sampling of favourable laterite landforms to define
Inferred resource
• Follow up dril ling for indicated resource• Determination of bulk densities and upgrading characteristic.
• Follow up dril ling of measured resource
• Bulk sampling and metallurgical testing
P T INCO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 46/79
P.T. INCO
Outlining of Ultramafic Area
• Reference/Published Geological map
• Aerial photograph, landsat/radar imageries• Ground mapping
P T INCO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 47/79
P.T. INCO
Outlining and Analysis of Structural Lineaments
• Highly tectonised rocks are more prone to penetration by
acidic surface waters and expose much larger area forchemical weathering.
• Major structures may also cause serpentinisation of the
ultramafic rocks.
• Aerial photograph, landsat and radar imageries
P.T. INCO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 48/79
P.T. INCO
Outlining Favourable Laterite Landforms
• Good laterite is generally associated with slopes 5-15%range, moderate slopes allow better drainage while stil lretaining the soil. Steep slopes allow rapid erosion oflaterite while depressions do not allow good flushingsystem to dissolve light elements.
• Landform is an extensive peneplaination of terrain.
• Landforms can be easily interpreted from aerialphotograph, landsat and radar imageries
P.T. INCO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 49/79
9th Relinquishment CoW Boundary
PeteaPetea Area AreaMahalonaMahalona
EBWB
SorowakoSorowako
SorowakoSorowako PlantPlant
P.T. INCO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 50/79
Reconnaissance Sampling of Laterite Landforms
• To check the presence of reasonable thickness and
nickel grades
• Power auger, RC dril ling, Lightweight Winkies, or even
hand auger can be used.
• 400m – 200m drill space
P.T. INCO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 51/79
Follow up Drilling for Indicated Resource
• To define Indicated Resources to ensure geological
continuity.
• Core Drill ing with 100m dril l space (may need closer
space if ore continuity is not uniform or in complex
geology/mixed rock type).
P.T. INCO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 52/79
Determination of bulk densities and upgrading
characteristic
• To determine tonnage factors, moisture content and
upgradeabil ity/screen recoveries to convert in situ volumes to
equivalent dry metric tonnes of potential plant feed.
• The best method: test pit or large diameter (20 cm) core drill ing.
P.T. INCO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 53/79
Follow Up Drilling for Measured Resource
• To further increase geological confident (ore continuity,
ore type and chemistry variability
• Core Drill ing with 100m dril l space (may need closer
space if ore continuity is not uniform or in complex
geology/mixed rock type).
P.T. INCO Mineral Resources and Mineral Reserves
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 54/79
Mineral Resources and Mineral ReservesCLASSIFICATION OF
MINERAL RESOURCES ANDMINERAL RESERVES(Based on CIMM philosophy)
PROBABLE PROVEN
MINERAL MINERALRESERVE RESERVE
INFERRED INDICATED MEASURED
MINERAL MINERAL MINERAL
RESOURCE RESOURCE RESOURCE
MINING ASPECTS
(Mineability,
Dilution)
MINING ASPECTS
(Mineability,
Dilution)
C
O N S I D E R A T I O N
O F E C O
N O M I C , M E T A L L U R G I C A
L ,
E N V I R O N M E N T A L , L E G A L A N D
O T H E R
A S P E C T
S
INCREASING GEOLOGICAL ASSURANCE AND CERTAINTY
(Continuity of grades, thickness, chemistry, etc.)
Low Medium High
FIGURE - 1Revised: May 6, 2001
P.T. INCO Bulk Sampling and Metallurgical Testing
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 55/79
Bulk Sampling and Metallurgical Testing
• To obtain:
Detailed geology (ore-waste contacts) at small scale
Mining methodGrade/Quality control sampling method
Reconcil iation between pre-mining and post mining
estimates
Detailed ore chemistry and mineralogy studies abd
processing implications
Reduction and Smelting test
• Size : 5,000 – 60,000 wmt.
P.T. INCO World Nickel Laterite Deposits
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 56/79
Cuba DominicanRepublic
Brazil
Columbia
Guatemala
Albania
GreecePhilippines
IndonesiaPNG
NewCaledoni Australia
Venezuela
BurmaIndia
Madagascar
Producing CountriesProducing Countries
Non Producing CountriesNon Producing Countries
Ivory Coast
Zimbabwe
EthiopiaBurundi
P.T. INCO LATERITE vs. SULPHIDE DEPOSITS
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 57/79
CUBA
INDONESIA
AUSTRALIA
LATERITES SULPHIDES
NEW CALEDONIA
PHILIPPINES
P.T. INCOWorld Nickel Laterite Resources
(Distribution by Contained Nickel)
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 58/79
( y )
Mt Resource % Ni Mt Ni %
Caribbean 2785 1.26 35.0 25
New Caledonia 1890 1.52 28.7 20
Indonesia 1401 1.63 22.8 16
Phil ippines 1162 1.30 15.1 11 Australia 1144 0.95 10.9 8
Africa 800 1.33 10.7 8
C. & S. America 661 1.60 10.6 8
Other 539 1.08 5.8 4
Total 10382 1.34 140 100
P.T. INCOWorld Nickel Laterite Resources
(Distribution by Contained Nickel)
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 59/79
(Distribution by Contained Nickel)
Caribbean
25%
New
Caledonia
20%
Indonesia
16%
Philippines11%
Australia
8%
Africa
8%
C. & S.
America
8%
Other
4%
P.T. INCO WORLD’S LAND-BASED Ni RESOURCES
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 60/79
100%2020.9620,976TOTAL
69%1401.3210,382LATERITES
31%620.5810,594SULPHIDES
Relative
%
Contained
Nickel
%
Ni
Mt
Ore
Excluding sea-based manganese nodules
P.T. INCO WORLD LATERITES – Grade/Tonnage Plot
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 61/79
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
0 50 100 150 200 250 300 350 400 450
Millions of tonnes of Resource/Reserve
% N
i G
r a d e
N.Cal.
Indep.PalawanMindanao
SOAPTAT
Inco Pomalaa
Larco
Apo
Soroako
Bahodopi
B.Alto Exmibal
Falcondo
SLN Hi grade
Koniambo
Goro Ni
Pinares
des Mayari
Sipilou
Murr in M. 6-20
Cawse 6-20
Marlboro
C 1-5
B 1-5
M 1-5
Raventhorpe
6-20
Bulong
6-20
Ramu R. Ambatovy
Prony
GagInv.
C.Matoso
Funguesso
Inco Coastal
P.Gorda
Mt.Marg.
Tocantins
Soroako
1 B lb Ni
2 B lb Ni5 B lb Ni
10 B lb Ni
15 B lb Ni
Moa
Hinatuan
Rio Tuba
Benguet
Codemin
Nicaro
R 1-5
Taganito
PumaOnca
Cupey Inco Pomalaa
Loma
LIM Producing (Yr 2000) LIM Likely to produce (by 2010) LIM Non-producing
SAP Producing (Yr 2000) SAP Likely to produce (by 2010) SAP Non-producing
P.T. INCO WORLD Ni PRODUCTION & RESOURCES
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 62/79
PRIMARY Ni PRODUCTION WORLD Ni RESOURCES
SULPHIDE
SULPHIDELATERITE
LATERITE
60%
40% 30%
70%
P.T. INCO MAJOR LATERITE PRODUCERS
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 63/79
100%467,310TOTAL
3.717,200Loma de Niquel (Anglo)Venezuela
5.827,227Falcando (Falconbridge)Dominican Rep.6.430,000 Anglo; othersBrazil
10.046,900Cerro Matoso (BHP-B)Columbia
13.261,500Eramet/SLNNew Caledonia13.563,000PAMCO; Hyuga; Nippon YakinJapan
14.467,383QNI (BHP-B); Minara Australia
16.075,000Cuba NickelCuba
16.979,100PT Inco; ANTAMIndonesia
% of
world
Mt NiProducersCountry
For 2003
P.T. INCOINDONESIA
Principal Nickel Laterite Deposits
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 64/79
500km
WEDA BAY
SULAWESI
KALIMANTAN
SERAWAK
PNG
IRIAN JAYA
HALMAHERA
SUMATRA
TIMOR
GEBE
OBISOROAKOBAHODOPI
POMALAA
GAG
WAIGEO
SENTANI
JAVA
P.T. INCO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 65/79
LATERITE MINING PROCESS
PT INCO - SOROWAKO
P.T. INCO PTI Concession
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 66/79
Malili
Original Concession
6,600,000 Ha
Current Concession
218,529 Ha (3.3%)
P.T. INCO
PT Inco Concessions Surround Sorowako
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 67/79
PT Inco Concessions Surround Sorowako
Processing Plant
EBWB
Petea
Lampesue N&S
Tanamalia
Lingkona
Lasubonti
Matano
Malili
Lingke
Lengkobale
Mahalona
MatanoLake
Towuti Lake
P.T. INCO Mine Equipment ~ 2006
E i t T t l U itT
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 68/79
511 m3 bucketFRONT SHOVEL
51100 tons payload
711 m3 bucketLOADER
16.5 m3 bucket
13.5 m3 bucket
985 tons payload
4550 HP
DOZER
TRUCK
BACKHOE
Equipment
114 m3 bucket
350 tons payload
Total UnitType
4200 HP
34350 HP
5125 tons payload
111 m3 bucket
P.T. INCOPT INCO Simplified Mining Flow Diagram
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 69/79
LandCLEARING
STRIPPING
of Overburdencapping
OVERBURDENDISPOSAL/
DUMPS
MINING(ORE DIGGING)
SAPROLITE
SCREENING
(OREUPGRADING)
(4 activescreening
plants)
FINAL MINE
PRODUCTto
WET ORESTOCKPILES
Capacity : 1milliontons
Mine Revegetation
EXPLORATIONDRILLING
Ore Bodymodeling
&
Mine Planning
P.T. INCO
Mining Process
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 70/79
P.T. INCO GEOLOGIST AND MINE ENGINEER KEY ROLES
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 71/79
GEOLOGIST
• Exploration (Mapping, Drilling,Logging, Geological Evaluation,
Geophysics)
• Orebody Modelling (GeologyDatabase, Geostatist ic, MineralResource/Reserve Estimation)
• Mine Ore Quality Control (MineGeologist)
• Mine Ore Reconciliation (Actualmined vs Model)
• Ore Blending
MINE ENGINEER
• Mine Planning (Life of Mine,LTP/STP, Equipment Calculation,
Design of mine pit, roads, dumps,drainage, quarry, etc)
• Blasting
• Mine Dispatch System (ModularMining System).
• Mining Operation
• Production Statistic and CostControl
P.T. INCO Rehabilitation workat disposal area
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 72/79
Before rehabilitation Land preparation
Vegetation development
P.T. INCO Mine Environment Control
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 73/79
P.T. INCO PROCESSING OF Ni LATERITES
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 74/79
• Pyrometallurgical processing
(Ore is melted)
Production of Ferro-nickel
Production of Ni-S matte
• Hydrometallurgical processing
(Ore is leached with acid solutions)
• Combined pyro and hydro process (Caron)
(Ore is reduced at high temperature, then leached)
P.T. INCO NICKEL SULPHIDE vs. LATERITE PROCESSING
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 75/79
Long to pay for high capitalCan be short to mediumProject size/life
High per lb of NiModest per lb of NiCapital cost
Modest due to compromise
for prevalent chemistry
High due to consistency of ore
chemistry and mineralogy
Ni recovery
High due to low Ni content.
High energy input required.
Modest due to high Ni content.
Sulphur provides latent heat.
Processing cost
Relatively high (per lb Ni)due to low upgradeabili ty
Relatively cheap (per lb Ni) dueto high upgradeabili ty
Ore/Conshipping
Low upgradeability. Final
grade generally <2.0% Ni.
Highly upgradeable to sulphide
concentrate
Upgrading
More varied in chemistryand mineralogy; stratified
More uniform in chemistry andmineralogy
Deposituniformity
Soft rock mining cheap.
Only open cast mining
Hard rock mining more
expensive. Many sulphides U/G
Mining
Nickel LateriteNickel Sulphide
P.T. INCO Processing• Drying
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 76/79
To reduce moisture content to +/- 20%. To reject high olivine/low Nickel rocks
To blend the ore
• Reduction
To further reduce moisture content to ~0%. To remove water crystal (LOI/Loss on Ignit ion)
To further blend the ore
Convert/reduce oxides to metallic form
Finalize blending recipe for smelter feed (addition of Carbon/coal and
Sulfur)
• Smelting
To remove remaining LOI
To complete reduction process
To melt sulfide and metallic phases to form a single liquid matte phase. To melt the remaining oxide phases to form a single liquid slag phase.
To separate the matte and slag phase based on density differences.
To discard the slag containing only small amount of nickel.
To tap matte containing most of nickel for further processing in theconverters.
P.T. INCO
DRYING AND REDUCTION PROCESS
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 77/79
P.T. INCO
MELTING PROCESS
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 78/79
P.T. INCO
7/23/2019 9-Early Magmatic & Nickel Laterite Deposit
http://slidepdf.com/reader/full/9-early-magmatic-nickel-laterite-deposit 79/79
Thank You
top related