luis magne

7/30/2019 Luis Magne

1/19

SAG MILLS OPTIMIZATION:

IMPLEMENTATION AND EVALUATION INDOA INS DE COLLAHUASI MINING

. agne, . ap a, . am rano, . u oz,G. Titichoca, I. Yutronic

CMDI de Collahuasi Lmagne Ingeniera


2/19

Compaa Minera Doa Ins de Collahuasi

Is located 4.400 meters

above sea level in theAndean plateau of the

Tarapac Region of the far

north of Chile, to 245 km

from Iquique.


3/19

Semiautogenous Grinding Circuit

CS - 1011

CS - 1012

BM 3

SAG 1

BM 4

SAG 2

Line #1

Line #2

DI 01

DI 02

Fe - 003

Fe - 004

Fe - 005

Fe - 006

Fe - 007

Fe - 008

Fe - 1031

Fe - 1032

Fe - 1033

Fe - 1034

Fe - 1035

Fe - 1036

Fe - 1037 Fe - 1038

CV - 05

CV - 06

SU - 01

CS - 001

CS - 002

CS - 003

CS - 004

PP- 03 PP- 04

PP- 05 PP- 06

CV - 07

CV - 09

PP- 1023 PP- 1024

PP- 1021 PP- 1022

BM

1013

SAG

1011

Line #3BM

1012

DI

1051

SU - 02

SU - 1021

CS -1013

CS - 1014

CV - 1036

CV - 1038

CV - 1037

CV - 1035

CV - 08

CV - 10

SAG Power Ball mill Mill ball Power

Line D x L, foot HP number D x L, foot HP

1 32 x 15 11.000 1 22 x 36,5 13.000

2 32 x 15 11.000 1 22 x 36,5 13.000

1011 40 x 24 28.000 2 26 x 38 20.000


4/19

Semiautogenous Mill Optimization

Trommel:

classification efficiency laundry water

SAG 1011: Charge baffle

Liners design

n runn on

End discharge:

Grates Pulp lifters

Cone discharge


5/19

SAG Mills Linings Design

h: altura media de lifter libre

d= distancia media entre lifters

rea entre lifters

1.941 cm2

d/h = 2,56 (706/276)li l ~

d = media distance between lifters

Area between lifters

h = free lifters media high

d/h: it relates liners distance and media box high between lifters Vlift/Vmill: it relates volume between liners and mill volume Lifting angle: is the attack lifters angle (one o more)

Using MillMED simulations is calculated the effect over: Useful impacts (Ball-Ore, Ore-Ore, Ore-Liners) Useless impacts (Ball-Ball, Ball-Liners)

li mol


6/19

SAG Mills Linings Design: Relation Between SAG

Diameter and Row Lifters Number

27

30 30

56

30 30 30 30

32 32

36 36 36 36 36 36 36 36 36

30 30 30

18

24

30

36

42

48

54

60

28 28 28 28 32 32 32 32 34 34 36 36 36 36 36 36 36 36 36 38 38 40

CantidadFilasLifters

4,50

0,96

1,07

2,00

0,94 0,94 0,941,00

0,79 0,75

3,3

2,9

1,6

3,4 3,3 3,3

3,1

4,0

4,2

0,00

0,50

1,00

1,50

2,00

2,50

3,00

3,50

4,00

,

28 28 28 32 34 34 36 38 40

Dimetro Molino (pies)

Cant. Filas Lifters/Dim. Molino (pies) Distancia Entre Centro de Lifters (pies)


7/19

SAG Mills Linings Design: SAG 1 - 2d= distancia media entre lifters

Differences:Pro oused Avera e

Smaller superior lifting angle (42 vs 52) Fall of the load near to foot of load

Bigger lifting angle in intermediate area (26) Better energy distribution and bigger load in flight

Lifting capacity independent of the waste

Bigger lifters height: 43 mm

Bigger load volume in flight Bigger duration of the lining (15% with 150 mm of

retirement thickness)

Original design

design

industry

d/h 2,44 2,19 2,32

V between lifters 6,9% 8,3% 7,7%

h/mill diameter 2,5% 2,9% 2,8%


8/19

SAG Mills Linings Design: SAG 1011

erences:

Variable angle since 35 Fall of the load near to foot of load

Better energy distribution and bigger load in flight

Lifting capacity independent of the waste

Bigger lifters height: 71 mm Bigger load volume in flight

Bigger duration of the lining (18% with 150 mm ofretirement thickness)

Original design

Propoused

design

Average

industry

d/h 4,37 3,19 2,32

V between lifters 5,1% 6,9% 7,7%

h/mill diameter 1,6% 2,4% 2,8%


9/19

Trommels Classification Efficiency

Mill Capacity Open

SAG Plant Diameter, feet Diameter, feet Long, feet Screen tph Wide, mm Long, mm Area, %

C.M.D.I. Collahuasi 32 14,4 13,6 No 1.320 15 30 27,0

Minera Los Pelambres 36 15,9 16,4 No 2.912 17 38 26,0

Minera Escondida 38 20,3 11,2 Si 5.170 25 60 29,0

Minera Antamina 38 15,9 16,4 No 5.472 15 38 23,0

C.M.D.I. Collahuasi 40 16,5 16,9 No 4.480 25 50 22,8

Minera Esperanza 40 15,4 15,4 Si 5.160 13 39 25,0

Trommel's Dimension Slot Size

Com arison criteria: arameter:

[ ]2

3

2

3

mareaOpen

h

mflowslurryVolumetric

hm

m

=


10/19

Trommels Classification Efficiency

Mill Pulp Trommel Free Flow by Free

SAG Plant Diameter, feet Diameter, feet Long, feet Flow, m3/h Area, m

2Area, m

2Area, m

3/m

2/h

C.M.D.I. Collahuasi 32 14,4 13,6 935 57,0 15,4 61

Minera Los Pelambres 36 15,9 16,4 2.063 75,9 19,7 105

Minera Escondida 38 20,3 11,2 3.570 66,2 19,2 186

Minera Antamina 38 15,9 16,4 3.877 76,0 17,5 222

C.M.D.I. Collahuasi 40 16,5 16,9 3.174 81,2 18,5 172

Minera Esperanza 40 15,4 15,4 3.656 69,4 17,3 211

Trommel's Dimension

32 feet Collahuasi SAG mills, have the best condition of slurry evacuation in trommel: = 61 m3/h/m2

Antaminas SAG mill has the worst condition of slurry evacuation in trommel: = 222 m3/h/m2

Esperanza and Escondidas SAG mills have high values of , but they have a screen Trommel of 40 feet SAG mill of Collahuasi has an high value of = 172 m3/h/m2.

Open Pulp Free Flow by Free

SAG 1011 Area, % Flow, m3/h Area, m

2Area, m

3/m

2/h

Initial Condition 22,8 3.174 18,5 172

Modification 1 35,0 3.174 28,4 112

Modification 2 31,8 3.174 25,8 123

Modification 3 29,2 3.174 23,7 134

28% more than the free area permit 22% more than flow discharge capacity


11/19

Trommels Classification Efficiency: Laundry

Water

SAG 1 - 2 SAG 1011


12/19

Pulp Lifters and Cone Discharge of SAG Mills

6,8

(6)

8

(7,25)

En blanco, medida el 16 de febrero de 2010

Recirculacin producto del

desgaste del pulp lifter largo

en el extremo de salida de la

carga

n amar o, me a or g na

Zona cada de carga


13/19


Cone discharge design affect:

Discharge flow capacity(then, mill capacity)

Slurry trajectory Slurry return from the

trunnion

Use of the trommel area forc as ca on

Excessive wear inpreferential areas of the

trommel

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0

1

1

1

2

1

3

1

4

1

5

1

6


14/19


182 mm

476 mm

583 mm

289 mm

385 mm

Size of SAG Grate: 64 mm

Strangulation of 182 mm


Opposing directors188 mm

328 mm

Cone discharge of SAG 1 - 2

Material: Polyurethane Material: Rubber

with ceramics


15/19


Size of SAG Grate: 64 mm

The short directors is near

to medium directors


697 mm

307 mm

674 mm

350 mm

Cone discharge of SAG 1011

95 mm

298 mm

503 mm

Material: Polyurethane Material: Rubber

with ceramics


16/19

Charge Baffle in SAG 1011 Trunnion - Trommel


17/19

Charge Baffle in SAG 1011 Trunnion - Trommel

It is possible to

eliminate one

blind line

Trunnion liner with positive angle

Grates in discharge zone, for maximum evacuation


18/19

Plant ResultsSAG 1 - 2:

The cilinder liners useful life increased in 15% (from 4,6 Mt to 6,3 Mt) Ball load level incresed since 12 to 16%, and until 18%, without risk of damage of linings Bigger operational speed from the begining of useful life of liners

By pass of fines decrease (washed pebbles)

Mill capacity increased up to 1.800 tph (from 1.400 tph, 28%)

SAG 1011:

The cilinder liners useful life increased in 34% (from 8,5 Mt to 11,4 Mt)

Bigger operational speed from the begining of useful life of liners The trommels mesh useful life incresed from 45 to 75 days Strong decrease of by pass of fines (washed pebbles) Pebbles belt is not a restriction of the process and the accidental detentions (for masive

discharge of load) were eliminated

Mill capacity increased up to 5.500 tph (from 3.900 tph, 41%)


19/19

Plant Results

We want to thank to all the suppliers that have participated and

contributed their experience and commitment in the carried out

developments.

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