Gekko IPJ Coal Separator Applications in Coal Preparation

transcript

Andrew Vince(Elsa Consulting Group)

Laurie Gibson, Peter Purdon(ACIRL)

Tim Hughes(Gekko Systems)

Elsa Consulting Group ACIRL Gekko Systems ACARP1

Narrative

• Identified Australian circular jigging technology successfully processing

metalliferous ores.

• Confirmed application in coal processing

• For 6 (30) mm x 0.25 mm

• Small modifications necessary for high floats recovery

• Tested out at small lab scale (1 t/h) – good

• Variables – developed DEM/CFD model

• Tested on site at 10 t/h. Not found maximum capacity yet.

• Circular – therefore capacity and efficiency both improve with radius.

• Need to go bigger.

Introduction

• Trend to installation of “three circuit” plants.

• This is due to:

• Matching size range to process technology

• Increased plant capacity

• Move to standardised plant design.

• Mid size fraction (eg 1.4 x 0.25mm) is currently

processed less efficiently than others.

• Gekko IPJ Coal Separator is targeting the mid size fraction.

Current Processes for Mid-sized Particles

• Spirals

• 1.5 mm top size, low unit capacity, feed rate

sensitive.

• Teetered bed separators

• Cut point varies with particle size.

• Multiple units with split feeds – complicated circuit.

• Reflux classifier

• New technology currently being rolled out in some companies.

• Consumes significant water volumes.

Gekko IPJ Coal Separator

• Gekko IPJ Coal Separator represents a competitor technology.

• Unique application possibilities due to high top size capability.

• Successfully deployed in metalliferous industry with more than 100

applications world-wide.

• This project considered application in coal industry.

Staged Approach

1. Laboratory scale testing.

2. CFD/DEM modelling.

3. Larger scale pilot testing on site.

Slurry Feed

Air bleed

Control box

Product barometric leg 1

Product barometric leg 2

Reject barometric leg

Hutch water

Pulse actuator

Hydraulic pump

In LinePressure Jig

IPJ 600 Unit 1 tph

Close-up of In Line Pressure Jig With Top Removed

Wedge wirescreen

Feed distributor

Ragging

InLine Pressure Jig Top Removed

Slurry Feed

PressureGauge

In Line Pressure Jig

InLine Pressure Jig Fully Assembled

Bowen Basin Pilot Scale

1.200 1.450 1.700 1.950 2.200 2.450

coeffi

Relative Density

Bowen Basin 6 x 2 mm

1.200 1.450 1.700 1.950 2.200 2.450

coeffi

Relative Density

Bowen Basin 2 x 0.5 mm ww

1.200 1.450 1.700 1.950 2.200 2.450

coeffi

Relative Density

Bowen Basin 2 x 0.25 mm ww

Hunter Valley Pilot Scale

1.200 1.450 1.700 1.950 2.200 2.450

coeffi

Relative Density

Hunter Valley 6 x 2 mm

1.200 1.450 1.700 1.950 2.200 2.450

coeffi

Relative Density

Hunter Valley 2 x 0.5 mm ww

1.200 1.450 1.700 1.950 2.200 2.450

coeffi

Relative Density

Hunter Valley 2 x 0.25 mm

Laboratory Results Summary

Bowen Basin Coal

6 x 2 mm 2 x 0.5 mm 2 x 0.25 mm

t/h D50 Ep ±0.1RD D50 Ep ±0.1RD D50 Ep ±0.1RD

0.76 1.44 0.075 23 1.475 0.200 11 - - -

0.55 1.49 0.100 9 1.55 0.213 5 - - -

0.94 1.50 0.150 6 - - - 2.00 - -

Hunter Valley Coal

6 x 2 mm 2 x 0.5 mm 2 x 0.25 mm

t/h D50 Ep ±0.1RD D50 Ep ±0.1RD D50 Ep ±0.1RD

1.03 1.50 0.098 6 1.58 0.195 2 - - -

1.60 1.54 0.105 20 1.66 0.180 6 - - -

1.13 1.55 0.129 16 - - - 1.94 - -

1.12 1.55 0.129 17 - - - 1.80 0.282 712

CFD/DEM Modelling

• 10 adjustable parameters.

• Too many to investigate experimentally.

• Develop CFD/DEM model to identify initial starting points for site-based pilot testing.

• Volumetric feed rate• Feed pressure• Feed % solids• Stroke length• Stroke frequency

• Stroke shape• Hutch water flow rate• Ragging diameter• Ragging density• Number of ragging layers

Hunter Valley Test Work

Issues Overcome

• Upward water flows

• Overcome with automation (commercially).

• Provision of back pressure.

• Migration of ragging.

Provision of Back Pressure

Blind Cyclones

Ragging Mobility

Site Tests

Feed Hutch Pressure

m3/h Dry t/h % Solids m3/h Bias kPa

Lower 9.32 3.16 20.5 26.0 -13.9 145

Upper 25.8 10.27 26.3 40.2 7.9 185

Stroke Ragging Near Gravity

Blind Cyclone Orifice

Cyc/min Length RD Layers ±0.1 RD mm

Lower 59 10 1.60 2.5 1 42

Upper 100 15 1.80 4.0 22 57

Site Test Results

1.25 1.45 1.65 1.85 2.05 2.25 2.45

Relative density

Partition coefficient curvesCoal A

6 x 2.0 mm

Series2

2.0 x 0.25 mm

Series4

6 x 0.25 mm

Series6 0

1.25 1.45 1.65 1.85 2.05 2.25 2.45

Relative density

Partition coefficient curvesCoal B

6 x 2.0 mm

Series2

2.0 x 0.25 mm

Series4

6 x 0.25 mm

Series6

1.25 1.45 1.65 1.85 2.05 2.25 2.45

Relative density

Partition coefficient curvesCoal C II

6 x 2.0 mm

Series2

2.0 x 0.25 mm

Series4

6 x 0.25 mm

Series6

Site Results Summary

Coal A

Feed 6 x 2 mm 2 x 0.25 mm

Ash (%) m3/h % Solids D50 Ep ±0.1RD D50 Ep ±0.1RD

21.3 24.5 24.4 1.89 0.112 1.0 - - -

Coal B

36.8 9.3 22.5 1.70 0.057 1.7 1.91 0.185 5.0

Coal C

53.3 10.0 25.6 1.43 0.069 18.0 1.49 0.172 7.1

47.6 18.0 24.1 1.57 0.081 3.7 1.82 0.223 3.2

All Site Test Results

0 5 10 15

Ash (db, %)

Coal A: 6.3 x 2.0 mm

Washability data

Operating Pt

Sizing results

0 5 10 15 20

Ash (db, %)

Coal A: 2.0 x 0.25 mm

Washability data

Operating Pt

Sizing results

50556065707580859095

0 10 20 30

Ash (db, %)

Coal B: 6.3 x 2.0 mm

Washability data

Operating Pt

Sizing results

50556065707580859095

0 10 20 30 40

Ash (db, %)

Coal B: 2.0 x 0.25 mm

Washability data

Operating Pt

Sizing results

All Site Test Results

0 10 20 30 40

Ash (db, %)

Coal C II: 6.3 x 2.0 mm

Washability data

Operating Pt

Sizing results

0 10 20 30 40

)Ash (db, %)

Coal C II: 2.0 x 0.25 mm

Washability data

Operating Pt

Sizing results

On-site and Lab Test Results

Low Cut Point High Cut Point

Scale Size (mm)

D50 Ep D50 Ep

Lab 6 x 2 1.43-1.55

0.075-0.15

Pilot 6 x 2 1.43 – 1.57

0.069 – 0.081

1.70 – 1.89

0.057-0.112

Lab 2 x 0.25 1.80-2.00

Pilot 2 x 0.25 1.49 0.172 1.82 – 1.91

0.185-0.223

Why you expect performance to improve with scale (diameter)?

• Conventional jig:

• Capacity related to width

• Efficiency related to length.

• Gekko IPJ Coal Separator

• Circular section

• Increasing radius increases

• Capacity

• Efficiency.

• Larger radius leads to increased cleaning.

Gekko IPJ Coal Separator(Extrapolated for coal)

<60 % solids

Ø1.50 m 40 tph

Ø2.40 m 80 tph

Ø3.50 m 200 tph

Tentative correlations found

Tentative linear correlations 6 x 2 mm: y = mx + C

y D50 Ep

x m C R2 m C R2

Ragging layers 0.03 0 0.67 0.003 -0.002 0.83

Ragging RD 1.46 -0.8 0.76 - - -

Vol feed rate (m3/h)

- - - 0.003 0.03 0.92

Tentative linear correlations 2 x 0.25 mm: y = mx + C

Y D50 Ep

X m C R2 m C R2

Feed % solids -0.1 5 0.89 - - -

Ragging layers 0.003 -0.002 0.67 - - -

Ragging RD 1.3 -0.4 0.46 - - -

Vol feed rate (m3/h)

- - - 0.006 0 0.90

Hutch bias (m3/h) - - - 0.005 0.13 0.84

Stroke length (mm) - - - 0.3 -0.01 0.93

Possible Circuitry

50 x 0 mm 50 x 6 mm DMC circuitDMC product

Flotation product

IPJ Product

Possible Applications – High NG

0 10 20 30 40

Ash (db, %)

PerformanceCoal C I: 6 x 2.0 mm

Washability data

Operating Pt

With scavenger40

0 10 20 30 40 50

Ash (db, %)

PerformanceCoal C I: 2.0 x 0.25 mm

Washability data

Operating Pt

With scavenger

0 10 20 30 40

Ash (db, %)

PerformanceCoal C II: 6 x 2.0 mm

Washability data

Operating Pt

With scavenger40

0 10 20 30 40

Ash (db, %)

PerformanceCoal C II: 2.0 x 0.25 mm

Washability data

Operating Pt

With scavenger

ImplicationsPlant Low cost capacity increases Better matching of incremental ashes

between circuits possible

Screen 6mm rather than 2 mm aperturesLess near sizeEasier screening

Reduced screen areas for desliming AND drain and rinseLess criticality on apertures

DMC Less impact of breakaway sizeHigher efficienciesEstimated 25% less feed tonnesLess medium recirculatingSmaller pumps

Less power consumptionLess maintenanceMuch reduced magnetite losses

IPJ For 1000 t/h ROM plant feed500 t/h in 6 x 0 mm fractionNeed= 3 x 2 units (rough/scav)

Increased longer term recovery through rougher/scavenger configuration.

CC More units handling 6 mm top size

Flotation No change

Conclusions

Gekko IPJ Coal Separator• Mature technology for metalliferous processing• Modified successfully for coal applications• Lab scale performance very good (600 mm, 1 t/h)• Site testing better (1000 mm, >10 t/h)• Strong evidence that can get even better (with size and further optimisation)• Possible applications

• Rougher/scavenger configuration• Treating 6 (30) x 0.25 mm particles• Very clean product requirements.

Recommendation

• Plant testing of rougher scavenger configuration

Grateful Acknowledgements

1. Australian Coal Association Research Program and Industrial Monitors.

2. Providers of Hunter Valley and Bowen Basin coals for laboratory testing.

3. Hunter Valley site management, technical and operations personnel.

4. UNSW for CFD/DEM modelling.

5. Organisers and officials of this conference.

6. You.

Elsa Consulting Group ACIRL Gekko Systems ACARP36

Gekko IPJ Coal Separator Applications in Coal Preparation

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