Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Predictive Mineralogy Process Control Exploration Remote Sensing Reserve Estimation.

Présentation au sujet: "Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Predictive Mineralogy Process Control Exploration Remote Sensing Reserve Estimation."— Transcription de la présentation:

1

2 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Predictive Mineralogy Process Control Exploration Remote Sensing Reserve Estimation Georesources & Geo-Imaging Research Group Georesources & Geo-Imaging Research Group © CSIRO Quantitative Microscopy On Line Vision Core Scanning 3D particle size & shape

3 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Range 50µm -> 5mm + 10 4 particles/min o Mechanical dispersion Vibration (tray) Acceleration (conveyor) o Suction Laminar air flow Free flowing powders Free flowing powders

4 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Range 500nm - 150µm + 10 5 particles / min Vacuum dispersion For dry powders Flow cell For wet powders suspensions emulsions,… Non free flowing powders Non free flowing powders

5 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Estimation of chromite content in UG2 slurries o Modified flow cell Identification of chromite grains (opaque) Real time estimation of chromite content and liberation Size and Mineralogy Size and Mineralogy 5 [chromite] from AA [chromite] from IMAGE

6 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Existing spectral databases o Specular reflectance of ore-forming minerals QDFIII 400nm-700nm (Criddle & Stanley, 1993) Extended to 1000nm (Brea et al., 2010) Mineralogy & Particle Size Mineralogy & Particle Size 6

7 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Existing spectral databases o Diffuse reflectance of rock forming minerals Speclab USGS, Grove et al. (1992) Mineralogy & Particle Size Mineralogy & Particle Size 7 < 45 µm < 125 µm < 500 µm Chalcopyrite Pyrite Specular (QDFIII)

8 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Best of both worlds o Diascopic imaging for opaques White LED illumination o Episcopic imaging Selected LEDs Eight wavelength Dichroic mirrors Dark field objective Multispectral Set Up Multispectral Set Up 8

9 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Gangue Silicates vs Sulphides Diascopic Imaging Diascopic Imaging 9

10 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Oxides vs Sulphides Episcopic Darkfield RGB Imaging Episcopic Darkfield RGB Imaging 10

11 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Chromite vs Pyrite o Photonfocus MV1 D1312ie 1312x1082 (binning) 3,1 µm/pixel 400 ms Episcopic Darkfield Spectral Imaging Episcopic Darkfield Spectral Imaging 11 Backlit image F0=405 nm F1=455 nm F3=590 nm F4=617 nm F2=530 nm F5=735 nm F6=950 nm

12 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Darkfield imaging o Reflectance angles Maximum reflectance depends on particle shape and λ Calibration and discrimination Calibration and discrimination Cu wire Ø=100 µm

13 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Darkfield imaging o Pyrite vs. Copper Percentile P 80 of intensity distribution within particle Combination of > P 80 per wavelength Discrimination Discrimination Pixels voted > P 80 for every λ Pyrite Ø=52 µm Mask P 80 Cu wire Ø=100 µm P 80 P 99 Raw spectrum

14 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement LYSC: Pyrite-rich (> 91%) LYSB: Mixed sulphides (Py+Cp+…) Particle sizing vs. 405nm/617nm band ratio Discrimination Discrimination Pyrite-rich (LYSC ) Mixed sulphides (LYSB) Pyrite-rich (LYSC ) Mixed sulphides (LYSB)

15 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement LYSC: Pyrite-rich (> 91%) LYSB: Mixed sulphides (Py+Cp+…) Particle sizing vs. 455nm/617nm band ratio Discrimination Discrimination Pyrite-rich (LYSC ) Mixed sulphides (LYSB) Pyrite-rich (LYSC ) Mixed sulphides (LYSB) Py Cp

16 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement LYSC: Pyrite-rich (> 91%) LYSB: Mixed sulphides (Py+Cp+…) Particle sizing vs. 405nm/617nm band ratio Discrimination Discrimination Pyrite-rich (LYSC ) Mixed sulphides (LYSB) Pyrite-rich (LYSC ) Mixed sulphides (LYSB) Grey sulphide (sphalerite, galena, arsenopyrite,…) (tbc) Yellow sulphides mix (pyrite,chalcopyrite,…)

17 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Improved flow cell imaging system o Combined dia- and episcopic imaging o Particle size, shape + mineralogy, (liberation) Multispectral imaging o Simple and flexible o Tunable to dedicated minerals Image processing o Spectra of brightest pixels (> P 80 ) to limit size and shape influence Mineralogy o Band-ratio discrimination Online mineralogy Online mineralogy 17

18 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement Mineralogical Analysis o Needs further calibration o Cross-validation with chemistry and XRD Discrimination limits o Gangue Carbonates vs. Silicates o Sulphides Cp, Py, Ga, Sp, Po,… o Oxides Hem vs. Goe; Ilm vs. Lcx vs. Rut; … Sample Preparation o Dilution needed for dirty and dense pulps Multimodal imaging o Add other imaging modules (i.e. SWIR, Raman,…) Online mineralogy Online mineralogy 18

19 Université de Liège - GeMMe - Génie Minéral, Matériaux & Environnement See you in Liège in 2015 See you in Liège in 2015 www.em-georesources.eu Liège, Belgium