5.- mineral processing_introduction_mcu_2011_luis magne.pdf

7/27/2019 5.- Mineral Processing_Introduction_MCU_2011_Luis Magne.pdf

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Mill Circuit UniversityWeir Minerals


Mineral Processingineral Processing

Mineral Processing: IntroductionMineral Processing: IntroductionLuis MagneLuis Magne


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Extractive Metallurgy:

Crushing

Metals Extraction:

Example Copper

Metals Extraction:

Example Copper

Process:

Exploration (Geology) Extraction (Minning)

Extractive Metallurgy:


Grinding

Classification

Concentration

Dewatering

Smelting Electro refinery

rus n

Leaching Solvent Extraction

Electro winning

Materials Process

EarthEarth


Elements in the Earth CrustElements in the Earth Crust

Elements Quantity, %

Oxygen (O) 46,6

Silicon (Si) 27,7

Aluminum (Al) 8,1

Iron (Fe) 5,0

Calcium (Ca) 3,6


Sodium (Na) 2,8

Potassium (K) 2,6

Magnesium (Mg) 2,1

Titanium (Ti) 0,5

99,0

Copper: 0,006%

Molibdenum: 0,00025%


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Copper in the Earth CrustCopper in the Earth Crust


OreOre

An ore is a type of rock that contains minerals with

important elements including metals. The ore is formed

through geological processes and it has a characteristicchemical composition.

An economic definition is: Ore is a mineral that can be

mined at a profit. For example:


CalcopiritaCalcopirita

CuFeS2

GalenaGalena

PbS

EsfaleritaEsfalerita

ZnS

OreOre

MoS2

MolibdenitaMolibdenita

Fe2O3

HematitaHematita MagnetitaMagnetita

Fe3O4

Cu ritaCu rita


FeS2

PiritaPirita AzuritaAzurita

Cu23(CO3)2(OH)2

Cu2O

GoldGold

Au

SilverSilver

Ag


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Ore DepositesOre Deposites

An ore deposit is a portion of the earths crust from

which some industrial raw material can be extracted at aprofit.

The interest elements concentration is called grade. Copper: % (bigger than 0,4%)


Molybdenum: % (bigger than 0,05%)

Iron: % (bigger than 25%)

Gold: g/t (bigger than 0,8 g/t or ppm)

Silver: g/t (bigger than 15 g/t or ppm)

Grade Variation of Copper in Main Chiles

Plants

Grade Variation of Copper in Main Chiles

Plants


RecoveryRecovery

Is the mass of element of interest obtained trough aconcentration process.

Mineral Processin Plant

Feed: 150 t/h

GF: 1,2% feedininterestofelementofmass

econcentratininterestofelementofmassR

tph

100

1,2tphfeedininterestofelementofMass 8,1150


Concentrate: 6,5 t/h

GC: 25,0%

Tails: 143,5 t/h

GT: 0,122%

tph100

25,0tpheconcentratininterestofelementofMass 625,15,6

%3,908,1

625,1100

tph

tphR


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Copper Production in ChileCopper Production in Chile


Mineral processing parameters for sulphur (concentration):

Copper Production in ChileCopper Production in Chile

2007 2008 2009 2010 2011

CopperGrade,% 1,09 1,10 1,05 0,97 0,94Recovery,% 87,9 87,7 88,1 87,6 87,8


Mineral processing parameters for oxides (leaching):

2007 2008 2009 2010 2011

Copper Grade,% 0,69 0,67 0,66 0,61 0,60Recovery,% 63,67 63,43 63,35 59,09 58,90

Total Mineral for ProcessTotal Mineral for Process



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Mine Material RemoveMine Material Remove


Minning Proyects in ChileMinning Proyects in Chile


Mineral ProcessingMineral Processing


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Mineral ProcessingMineral Processing

Unit process:

Size reduction process

Size classification


Ore Concentration

Dewatering

Minerals ConminutionMinerals Conminution

Size reduction process:

Blast

Crushing

Conventional grinding

Autogenous grinding


Size classification:

Screens

Hydrocyclones

Minerals ConcentrationMinerals Concentration

Ore concentration:

Gravitational concentration

Magnetic concentration

Flotation


Dewatering:

Thickening

Filtration

Drying


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Minerals ProcessingMinerals Processing


Minerals ProcessingMinerals Processing


Slurry or PulpSlurry or Pulp


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Slurry or PulpsSlurry or Pulps

Homogenous mixture between solidsparticles and a liquid

A slurry can be described as a two phase

medium (liquid/solid). In mineral processing, the solid particles are

ores and the liquid is industrial water.


Pulpvolume =Solidvolume + Liquidvolume

Vp = Vs + Vl

PulpMass =Solid mass + Liquidmass

Mp = Ms + Ml

Mineral PulpsMineral Pulps

Pulp in movement: if is the resident time ofthe pulp in a control volume

Volumetric flow rate: is the volume of fluidwhich passes through the control volume inthe resident time, .

V


pp

lslsp

ll

ss

VQ

VVQQQ

VQ

Q

Solids:

Liquid:

Pulp:


Mass flow rate: is the mass of fluid whichpasses through the control volume in theresident time, .

ss

MG Solids:


pp

lslsp

ll

MG

MMGGG

MG

Liquid:

Pulp:


10/32


Pulp density :

ls

lsp

p

pp

VV

MM

V

M

In a static system:


ls

lsp

p

pp

QQ

GG

Q

G

In a dynamic system:

Solid Concentration in PulpsSolid Concentration in Pulps

Solid concentration involume Cv: it is the fractionof volume of solid that there

is in the total volume of

pulp

vs

p

s

s l

vs

p

s

s l

C =V

V=

V

V +V

C =Q

Q=

Q

Q + Q


Solid concentration inweight Cp: it is the fractionof mass of solid that there is

in the total mass of pulp

ps

p

s

s l

p

s

p

s

s l

C =M

M=

M

M +M

C =G

G=

G

G +G


Cp in function of Cv:

CC

Cp

v s

l v s l

100100

( )

Cp

in function ofp

:


Cps p l

p s l

100

( )

( )

Cv in function ofp:

Cvp l

s l

100


11/32


p in function of Cv:

lpps

lpv

CC

CC

)100(100

Cv in function of Cp:


100

)( lsvlp

C

p in function of Cp:

plps

lsp

CC

)100(100


Example:

A mineral process plant, processes 500 mtph of ore with

density of 2,8 mt/m3. In the mill, the pulp has a Cp of

80,0% and in the flotation the Cp is 32,0%. Determine:

o How much water is necessary for grinding process


o How much additional water it should be added in the

flotation process

o Which is the pulp density in both cases?

a) 125 m3/h; b) 937,5 m3/h; c) 2,06 t/m3; 1,26 t/m3

Water in Mineral ProcessingWater in Mineral Processing


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Water in Mineral ProcessingWater in Mineral Processing

CrushingPlant

ROM

(3 5%humidity)

GrindingPlant

Cp=80%

ConcentrationPlant Tails ThickeningTailsde osit

FreshWater RecycledWater


If 60% of water is recovered, then is necessary 1 m3 of water for 1t of ore.

Cp=30%

Concentrate

Cp=62%

Thickening

Cp=60%

Filtration

Dryconcentrate(8 10%humidity)

Recycled

Water

Size Reduction ProcessSize Reduction Process

Size reduction is relevant in mineral

processing, because it have:

High capital cost (investment)

Reduction SizeReduction Size


o Equipment process

High operational cost

o Energy

o Steel consumption


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Why Size Reduction?Why Size Reduction?

Why Mineral Size Reduction?Why Mineral Size Reduction?


Mineral Size Reduction TargetMineral Size Reduction Target

To liberate interest minerals of non interestmaterials or gangue (concentration)

To promote fast chemical reactions by a big

superficial area exposition (hydrometallurgy)


Degree of Liberation:

The degree of liberation of a certain mineral orphase is the percentage of that mineral orphase occurring as free particles in relation tothe total of that mineral occurring in the freeand locked forms


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Usually the first steps are doing in a mine for

transport objective.

The following steps, crushing and grinding, are

doing made to separate the interest minerals of

the gangue.

Size Reduction StepsSize Reduction Steps


The final product have different types of

particles:

Fully liberated

Partially liberated

Non liberated or locked

Fully liberated: more than 80%is mineral

Partially liberated:oMixed: between 80 y 50% ismineral

Asociaciones Mineralgicas y Grados de

Liberacin

Asociaciones Mineralgicas y Grados de

Liberacin


oAssociate: between 50 y 15%is mineral

Non liberated:oLess than 15% is mineraloOccluded: mineral is inside ofgangue

Size Reduction MechanismSize Reduction Mechanism


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Fracture


Abrasion

Fracture

by compression



by shearing

by impact

Size Reduction Mechanism and EquipmentSize Reduction Mechanism and Equipment

MECHANISMMECHANISM

COMPRESSIONCOMPRESSION IMPACTIMPACT COMPRESSIONCOMPRESSION--IMPACTIMPACT


Jaw Crusher

Giratory Crusher

Cone Crusher

Rolls Crusher

Impact crusher

Impact millBars mill

Balls mill

Autogenous mill

Semiautogenous mill


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Size Reduction Processize Reduction Processize Reduction Processize Reduction Process

Size Reduction ProcessSize Reduction Process

Size reduction process depend of product target

Product target depend of the next process:concentration (flotation, magnetic concentration,

gravitational concentration), cyanuration, leaching,etc.

If the target is fine product (150 to 300 m):


onven ona r n n c rcu : or crus ng

steps and 2 grinding steps

Unitary grinding circuit: 3 crushing steps and 1grinding step

Semiautogenous grinding circuit: 1 crushing stepand 1 grinding step

If the target is medium size (20 mm): 3 crushing steps.

Conventional Grinding Circuit

Crusher Plant

Conventional Grinding Circuit

Crusher Plant

Primary crusher:

Run of mine material (ROM), with sizes until 60 inch(1,5 m). Product of 6 to 8 inch (15 to 20 cm)

Secondary crusher:

Work with product of the primary crusher. Product of2 to 3 inch (5 to 8 cm)

Tertiary crusher:


Work with product of the secondary crusher. Productminus of inch (12 mm) for mill circuit.

Primary mill:

The crusher plant product is grinding until 6 to 4 mm.

Normally is wet.

Secondary mill:

The product of primary mill is grinding for produceparticles of 200 m (may be 100 to 300 m or more).


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Unitary Grinding Circuit

Crusher Plant

Unitary Grinding Circuit

Crusher Plant

Primary crusher:

Run of mine material, with sizes until 60 inch (1,5m). Product of 6 to 8 inch (15 to 20 cm)

Secondary crusher:Work with product of the primary crusher.Product of 2 to 3 inch (5 to 8 cm)

Tertiary crusher:


Work with product of the secondary crusher.Product minus of inch (12 mm) for mill circuit.

Milling:

The crusher plant product is grinding for produce

particles of 200 m (may be 100 to 300 m ormore).

Semiautogenous Grinding CircuitSemiautogenous Grinding Circuit

Primary crusher:

Run of mine material, with sizes until60 inch (1,5 m). Product of 6 to 8 inch(15 to 20 cm)

Semiautogenous mill:

Work directl with the crusher roduct


and produce material with 12 mm.

Normally is wet.

Secondary mill:

The product of primary mill is grinding

for produce particles of 200 m (may be100 to 300 m or more).

FAG o SAGFAG o SAG

Size Controlize Controlize Controlize Control


18/32

Size Distribution of Mineral Particlesize Distribution of Mineral Particles

The sizes distribution of the mineralparticles can be represented by a set ofnumbers representing the cumulative weight

fraction below size xi versus xi: F(xi) vs xi

100


10 100 1000 10000 1000001

10

AcumuladoPasante,%

Tamao de partcula, m

Size Distribution of Mineral Particlesize Distribution of Mineral Particles

Ro-Tap


SievesSieves

Mesh number is the slots number by onelineal inch.

Size Distribution of Mineral Particlesize Distribution of Mineral ParticlesAbertura Serie ASTM

N de tamiz

Serie Tyler

N de tamiz

107.6 mm101.6 mm

90.5 mm76.1 mm

64.0 mm

4.24"4.00"

31/2"3"

21/2"

53.8 mm50.8 mm45.3 mm38.1 mm32.0 mm26.9 mm

2.12"2"

13/4"11/2"11/4"1.06"

25.4 mm 1"


22.6 mm19.0 mm16.0 mm13.5 mm

7/8"3/4"5/8"

0.530"

0.883"0.742"0.624"0.525"

12.7 mm11.2 mm9.51 mm8.0 mm

6.73 mm6.35 mm

1/2"7/16"3/8"

5/16"0.265"

1/4"

0.441"0.371"2.172"

3

5.55 mm

4760 m4000 m3360 m2830 m2380 m

3 1/2

45678

3 1/2

45678


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Size Distribution of Mineral Particlesize Distribution of Mineral ParticlesAbertura Serie ASTM

N de tamizSerie TylerN de tamiz

2000 m1680 m1410 m1190 m1000 m

1012141618

910121416

841 m707 m595 m500 m420 m

2025303540

2024283235


m297 m250 m210 m

506070

486065

177 m149 m125 m105 m

80100120140

80100115150

88 m74 m63 m53 m44 m

37 m

170200230270325

400

170200250270325

400

Size Distribution of Mineral Particlesize Distribution of Mineral ParticlesTotal mass 537,6 g

I nter va l Rep re se ntative P ar ticle Mass P ar tial Cummu la tive

Mesh Mesh size, m g fraction, % fracti on, %

10 - 14 10 1680

14 - 20 14 1190

20 - 28 20 841

28 - 35 28 595

35 - Bottom 35 420



10 - 14 10 1680 65,4

14 - 20 14 1190 93,0


20 - 28 20 841 145,4

28 - 35 28 595 122,6

35 - Bottom 35 420 110,9

537,3



10 - 14 10 1680 65,4

14 - 20 14 1190 93,0

20 - 28 20 841 145,4

28 - 35 28 595 122,6

35 - Bottom 35 420 111,2537,6

Size Distribution of Mineral Particlesize Distribution of Mineral ParticlesInterva l R ep re se ntat ive P ar ticle Mas s P ar tial C um mu la tive

Mesh Mesh size, m g fraction, % fraction, %

10 - 12 10 2380 65,4 12,17

12 - 30 12 2000 93,0 17,30

30 - 270 30 595 145,4 27,05

270 - 400 270 53 122,6 22,81

400 -(-400) 400 37 111,2 20,68

537,6 100,00

Interva l R ep re se ntat ive P ar ticle Mas s P ar tial C um mu la tive

Mesh Mesh size m fraction % fraction %


, , ,

10 - 12 10 2380 65,4 12,17 100,00

12 - 30 12 2000 93,0 17,30 87,83

30 - 270 30 595 145,4 27,05 70,54

270 - 400 270 53 122,6 22,81 43,49

400 -(-400) 400 37 111,2 20,68 20,68

537,6 100,00

80% size (F80) is the 80% passing size in the

distribution.

Which is the F80 of this distribution size?


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Size Reduction Definitionsize Reduction Definitionsize Reduction Definitionsize Reduction Definitions

Size Reduction Caracterizationize Reduction CaracterizationSize Reduction

Power consumption

Pot in kW

Feed Product

F80

F, mtph

P80

P=F, mtph

100


10 100 1000 10000 100000 1000000

0.1

1

10

AcumuladoPasante,

%

Tamao de Partcula, m

Alimentacin Molino SAG

Descarga Molino Sag

Reduction RatioReduction Ratio

Ratio of feed size to product size for acrushing or grinding operation:

RF

Pr

80

80


RF

Pr

max

max

Inefficient process:

Rr = 1


21/32

Consumed Specific Energy (CSE)Consumed Specific Energy (CSE)

CSE is the necesary energy to reduce a ton ofmineral:

kWPotCSE


Inefficient process:

F = 0 mtph

mtp

Reduction Ratio and SECReduction Ratio and SEC

The ideal condition is to obtain themaximum reduction ratio and minimumCSE:


0CSERr

Sizing and

Sizing and


22/32

Sizing and Size ClassificationSizing and Size Classification

Sizing is the general term for separation ofparticles according to their size. The simplestsizing process is screening.

Classification refers to sizing operations that

exploit the differences in settling velocitiesexhibited by particles of different size.Classification equipment may includeh droc clones and rotatin trommels.


.

Feed

Fine

Coarse

Sizing and Size ClasificationSizing and Size Clasification

DPA

Global mass balance:

coarseinflowMassfineinflowMassfeedinflowMass

Mass balance by size: Feed

FineP, mtph

pi

CpR


iiiDdPpAa

Mass balance of water:

D

D

P

P

A

A

Cp

CpD

Cp

CpP

Cp

CpA

)100()100()100(

A, mtph

ai

Coarse

D, mtph

di

CpA

CpD

10

100

pa

sante,

%

Sizing and Size ClassificationSizing and Size Classification


10 100 1000 10000 1000001

Granulometras:

Alimentacin

Descarga

RebalseAcumulado

Tamao de partcula, m


23/32

Size Reduction Circuitsize Reduction Circuitsize Reduction Circuitsize Reduction Circuits

Open CircuitOpen Circuit

Size ReductionFeed, F Product, P

F80 P80


PF

productinflowMassfeedinflowMass

Direct Closed CircuitDirect Closed Circuit

Size

Reduction

Feed, F

Classification

F80

Water

Water

Coarse

Product, DG

A


Fine Product, P

P80GDF

PDA

GA

ass ow a ance

Mass balance by size:

iiiGgDdFf

iiiPpDdAa

FP


24/32

Inverse Closed CircuitInverse Closed Circuit

Size Reduction

Feed, F

Classification

F80Water

Water

CoarseProduct, D

A

G


Fine Product, P

80

AGF

PDA

GD

Mass flow balance

FP

Mass balance by size:

iiiAaGgFf

iiiPpDdAa

Circulating Load RatioCirculating Load Ratio

Equipo deF G FF

Circulating Load, C, is the ratio of the massflowrate of solids in the classifier dischargestream to the mass flowrate of solid in theclassifier overflow stream:


Reduccin de

Tamaos

Producto

final

Clasificador

Q

D

A

Equipo de

Reduccinde

Tamaos

Q

Clasificador

D

A

GEquipo de

Reduccinde

Tamaos

Q

Clasificador

D

A

G

P

DC 100

P

DC 100

P

R


FeedA, mtph

ai

Fine

P, mtph

pi

CpA

CpR

DPA

iiiDdPpAa

D

D

P

P

A

A

Cp

CpD

Cp

CpP

Cp

CpA

)100()100()100(


)(

)(100

ii

ii

ad

paC

CoarseD, mtph

diCpD

PDA

DAP

CpCpCp

CpCpCpC

)(

)(100

Since mass balance by size:

Since mass balance of water:


25/32


Feed

A, mtph

ai

Fine

P, mtph

pi

CpA

CpR

PDA

DAP

CpCpCp

CpCpCpC

)(

)(100

Example 1:

CpA = 60%

CpD = 80%

CpP = 30%


Coarse

D, mtph

diCpD

Example 2:

CpA = 60%

CpD = 78%

CpP = 35%

R: Example 1=400%: Example 2=309,5%

Size Reduction Circuit EvolutionSize Reduction Circuit Evolution


Size Reduction Circuit Evolution:60s Decade

Transporte

a Proceso

Chancado

Primario

(Mandbulas)

Chancado

Secundario

(Cono

estndar)Molino

A Flotacin


Conventional circuit: Conventional blast Jaw primary crusher Symons cone crusher, secondary and terciary Mills of 12 ft, 950 kW The same power in both mill steps Ball mill circuit is direct Classification in spirals

Chancado

Terciario

(Cono

C. corta)

Tolva de Finos

Molino

de Barras

de Bolas


26/32

Transporte

a Proceso

Chancado

Primario

(Mandbulas)

Chancado

Secundario

(Cono olino

A Flotacin



Unitary circuit:

Conventional blast Jaw primary crusher Symons cone crusher, secondary and terciary Ball mills of 16,5 ft, 3.000 kW Ball mill circuit is inverse Classification in small hydrocyclon

estndar)

Chancado

Terciario

(Cono

C. corta)

Tolva de Finos

de Bolas

SAG mill Circuit:

Conventional blast Giratory primary crusher SAG mills of 36 ft, 11.200 kW Balls mills of 18 ft, 4.800 kW Power of primary mill is bigger than

secondary mill Ball mill circuit is inverse

Transporte

a Proceso

Chancado

Primario

(Giratorio)

Stock



uster of y rocyc ons of inc

Molino

de Bolas

A Flotacin

Clasificador

Molino SAG

Pebbles

SAG mill circuit: Conventional blast Giratory primary crusher SAG mills of 40 ft, 19.400 kW Balls mills of 24 ft, 10.500 kW Power of primary mill iqual to secondary mill Pebbles crusher Ball mill circuit is inverse

Cluster of hydrocyclon of 26 inch

Transporte

a Proceso

Chancado

Primario

(Giratorio)

StockStock

PilePile


Pebbles


Molino

de Bolas

A Flotacin

Clasificador

Molino SAG


27/32

SAG mill circuit: Selective blast Giratory primary crusher Pre crushing SAG mills of 40 ft, 24.000 kW

Balls mills of 27 ft, 18.650 kW Power of primary mill less than secondary

mill Pebbles crusher Secundar circuit is inverse

Circuitos de Reduccin de Tamaos:Dcada del 2000

Transporte

a Proceso

Chancado

Primario

(Giratorio)

Stock

Pile


Pebbles crushed to ball mills Cluster of hydrocyclons de 33 inch

Molino

de Bolas

A Flotacin

Clasificador

Molino SAG

Prechancado

(Cono

serie moderna)

Pebbles

Concentration ProcessConcentration Process


Feed

Mf , G f

Tail

Mt , Gt


Concentrate

Mc , Gc


28/32

Concentration CircuitConcentration Circuit

Rougher o Bulk:

Is the first concentration step. Their objective is tomaximize the recovery. Produce a rougher concentrate

and rougher tails.

Scavenger:


or w roug er a s, e r o ec ve s o

supplement the recovery. Produce a scavengerconcentrate and scavenger tails.

Cleaner:

Work with rougher concentrate, their objective is to

maximize the concentrate grade. Produce a cleaner

concentrate and cleaner tails.


Alimentacin

fresca

Relave

finalRougher Scavenger

Rougher

Feed

Tail


Concentrado

final

Scavengercleaner

Cleaner

Concentrate

Alimentacinfresca

Relave

finalRougher

ScavengerCleaner


Feed

Tail


Concentradofinal

cleaner

RecleanerScavengerrecleaner

Concentrate


29/32


Recovery, R (%):

100feedininterestofelementofmass

econcentratininterestofelementofmassR

Feed

Concentrate

MF , GF

MC, GC

Tail

MT, GT


100FF

CC

GM

GMR

Concentration Ratio, K (%):

masseConcentrat

massFeedK

C

F

M

MK


Example:

A mineral process plant, processes 1000 mtpd of ore

with copper feed grade of 1,3%. The concentrate grade is

28% and the tail grade is 0,10%. If the plant produces 43

mtpd of concentrates and 957 mtpd of tails, determine:


o Copper mass in each flow

o Recovery

o Concentration ratio

a) 13,0, 12,04, 0,96 mtpd; b) 92,6%; c) 23,25


Material balance:

tailinflowMasseconcentratinflowMassfeedinflowMass

Ore balance:

Mf= Mc+ Mt

Feed

MF , GF

Tail


Element balance:

Mf Ga = Mc Gc + Mt Gt

Concentrate

MC, GC

T, T


30/32


Concentrate mass:

Recovery:Feed

MF , GF

Tail

F

TC

TFC

MGG

GGM

CTFGGG )(


Concentration Ratio: ConcentrateMC, GC

T, T

FTC GGG )(

TF

TC

GG

GGK


Alimentacinfresca

Relavefinal

Feed

Tail

2605 tph1,29% Cu

Example:

Which is the flow mass in each point?


Concentradofinal

ougher

Scavengercleaner

Cleaner

Concentrate

,

13,57% Cu7,88% Cu

5,22% Cu

30,93% Cu

10,63% Cu

0,22% Cu

0,12% Cu

Relationship Between

Consumed Energy and Particle

Relationship Between

Consumed Energy and ParticleSizeSize


31/32

Size Reduction and

Consumed Specific Energy

Size Reduction and


Primary crushing: < 1 kWh/t

Secondary crushing: Between 1 to 2 kWh/t

Tertiar crushin : Between 1 5 to 3 kWh t


,

Primary mill: Between 4 to 8 kWh/t

Secondary mill: Between 6 to 20 kWh/t

BondBonds laws law(Bond(Bonds third theory)s third theory) BondBonds laws law(Bond(Bonds third theory)s third theory)

EnergyEnergy Particle SizeParticle SizeEnergyEnergy Particle SizeParticle Size

11

The Bonds law assumes that the total work useful inbreakage is inversely proportional to the square rootof the size of the product particles:


WI is the work index (kWh/t) which expresses heresistance of the material to crushing and grinding;and F80 and P80 are the 80% passing size of the feedand the product (m), respectively.

8080

10FP

WICSE

WI depend:

Ore (resistance at comminution)

The machine used

EnergyEnergy Particle SizeParticle SizeEnergyEnergy Particle SizeParticle Size


WI is determined in a standard laboratory test


32/32

Reduction Ratio and


Reduction Ratio and


The balance between capacity and reductionratio is:

11 kWPot

Capacity Reduction ratio


8080 FPi

t/hA

In a first evaluation, we need:

CSE

Wi

Circulating Load

F80 and P80

Solid bypass in classification




Mineral Processingineral Processing

5.- mineral processing_introduction_mcu_2011_luis magne.pdf

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