Download pdf - Gavin Diener, Allied Mineral Laboratories: Applying Gravity Separation Techniques to Fine Iron Ore

ALLIED MINERAL LABORATORIES ALLIED MINERAL LABORATORIES

FINE IRON ORE

BENEFICIATION

GAVIN DIENER

NOVEMBER 2013 FE TECH 2013 - FINE IRON ORE BENEFICIATION

GAVIN DIENER ALLIED MINERAL LABORATORIES

Slide 2

Content

• Introduction

• Characterisation

– What do you need to know before you start?

• Equipment selection

– Matching the flowsheet with the material

– Optimised flowsheet design

• Testwork program

– Characterisation

– Laboratory scale

– Pilot scale

• Conclusion



Slide 3

What do you need to know before you start?

• Particle size distribution

• Typically between 45 micron and 1 mm

• Relative distribution of Fe and gangue elements

• Heavy liquid separation

• SG of 2.9-3.3

• Mineralogy / Microscopy

• Liberation

• Mineral assemblage

• Magnetic separation profile

Characterisation



Slide 4

0%

10%

20%

30%

40%

50%

60%

70%

80%

0% 10% 20% 30% 40% 50% 60% 70%

SiO

2 g

rad

e in

fee

d (

%)

Fe grade in feed (%)

Ore 1

Ore 2

Ore 3

Ore 5

Ore 6

Ore 4

Ore characterisation



Slide 5

Equipment selection

Center

To Cons To Tails

High SG Low SG

Spirals



Slide 6

Equipment selection

To Underflow

To Overflow

High SG Low SG

Upcurrent classification



Slide 7

Equipment selection

High SG Low SG

0

10

20

30

40

50

60

70

80

90

100

10 100 1000

% M

as

s p

as

sin

g

Particle size (micron)

O/F

U/F


To Underflow

To Overflow



Slide 8

0

10

20

30

40

50

60

70

80

90

100-1

06u

m

+1

06-1

25 u

m

+1

25-1

50 u

m

+1

50-2

12 u

m

+2

12-2

50 u

m

+2

50-3

00 u

m

+3

00 u

m

Pro

po

rtio

n r

ep

ort

ing

to

un

derf

low

Mass




Slide 9

0

10

20

30

40

50

60

70

80

90

100-1

06u

m

+1

06-1

25 u

m

+1

25-1

50 u

m

+1

50-2

12 u

m

+2

12-2

50 u

m

+2

50-3

00 u

m

+3

00 u

m

Pro

po

rtio

n r

ep

ort

ing

to

un

derf

low

Mass

Fe

SiO2




Slide 10

Flowsheet design

Underflow

Overflow

Flowsheet options

• Spirals only

• Classifier only

• Classifier with underflow spirals

• Classifier with overflow spirals

• Classifier with both sets of spirals



Slide 11

Equipment selection

To Underflow

To Overflow

Center

To Cons To Tails

Center

To Cons To Tails



Slide 12

0%

10%

20%

30%

40%

50%

60%

70%

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Cu

mu

lati

ve

Fe g

rad

e (

%)

Cumulative yield to concentrate (%)

U/F 1

O/F 1

Spiral results



Slide 13

0%

10%

20%

30%

40%

50%

60%

70%

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Cu

mu

lati

ve

Fe g

rad

e (

%)

Cumulative yield to concentrate (%)

U/F 1

O/F 1

O/F 2

Spiral results



Slide 14

Testwork programs

Characterisation

Particle size distribution

Mineralogy

Heavy liquid separation

Sample sizes < 1 kg

Laboratory scale testwork

Laboratory gravity

separation

Air tables and wet tables

Sample sizes

5 to 20 kg

Pilot scale testwork

Pilot scale classification

Plant scale spiral

separators

Sample sizes

> 100 kg



Slide 15

• Understand the ore

• Consider the appropriate flowsheet

• Consider the optimised testwork plan

• Gravity separation on fine iron ore has produced exceptional results

Conclusion

ALLIED MINERAL LABORATORIES

THANK YOU