1. N. Malumbazo, M. Ndhlalose and N. J. Wagner
LEACHING OF URANIUM FROM COAL USING SAMPLES FROM THE SPRINGBOK FLATS COALFIELD: ACID LEACHING.
N. Malumbazo, M. Ndhlalose and N. J. Wagner
MSc Project: Council for Geoscience and Wits University
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2. Presentation Outline Introduction Project rationale
Aims and Objectives
Methodology
Results
Conclusions
Future work
Acknowledgments
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3. Introduction and Project Rationale
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4. Introduction South Africa sixth in coal production in world
19 Coalfields in SA
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5. Project Rationale
SFC not mined to any degree of economic profit, partly due to the presence of U in the coal.
SA’s Department of Mineral Resources Beneficiation Strategy - Disentangle uranium and coal in the Springbok flats coalfield.
SA’s Integrated resource plan - Increase energy sources by 2030.
Limited research about the amount of uranium that is associated with coal & leaching of uranium from coal.
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6. Integrated resource plan for electricity
Now
Future
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7. Aim and Objectives Aim:
Assess feasibility of extracting U from selected SFC coal samples using acid leaching.
Objectives:
Obtain 5 freshly drilled SFC borehole cores
Determine the coal quality.
Quantify U present in coal.
Identify the coal samples with high U concentration
Acid medium to leaching of U from coal
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8. Methodology
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9. Scope of work 2015 International Pittsburgh Coal Conference
Drilling and Storage
Splitting
ICP-MS
Ultimate, Prox and CV
Leaching
Optimized leaching
Ur detection
Coal quality
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10. Drilling and Storage
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11. Drilling and Storage 2015 International Pittsburgh Coal Conference
Carbonaceous shale
Bright coal bands
Calcite cleats
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12. Leaching Sulphuric acid leaching
Sulphuric acid- Previously successful
Effect of pH- varying pH, keeping time intervals and temperature const.
Effect of time- vary time, keep pH and temperature constant
Effect of temp- vary temp, keep pH and time constant
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13. Leaching experiments Reaction conditions Temperature (0C) pH
Time (hours)
Temperature variation
25, 45, 65
0.5 8
pH variation 25
0.5, 1, 1.5
Time variation
4, 8, 24

14. RESULTS AND DISCUSSION
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15. Coal quality results
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16. U detection results U in coal zone world average- 2ppm (Swaine, 1990)
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17. U detection results
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18. U results relative to coal quality
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19. Recap 2015 International Pittsburgh Coal Conference
Drilling and Storage
Splitting
ICP-MS, INAA, XRF
Ultimate, Prox and CV
Leaching
Optimized leaching
Ur detection
Coal quality
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20. Leaching samples Sample name Borehole U [INAA] U [ICP-MS] 1416 BH5 LCZ
8.93
8.6
1417
11.8
9.8
1421
BH3
161
145.9
1422
15.6
11.3
1429
BH2
86.9
85.9
1436
BH1
64.6
34.1
1437
43.2 13
1438
39.4
19.4
1439
29.3
20.9
1440
11.5
6.2
1443
BH4
33.5
34.4

21. Leaching Results- Time Effect
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22. Leaching Results- pH effect
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23. Leaching Results- Temperature effect
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24. Conclusions and Future Work
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25. Conclusions: Coal quality
BH1 and the UCZ in BH5 ash contents >50% for all the samples; the coal zones are made up almost entirely of carbonaceous shale.
BH2 had coal quality that resembles a typical South African bituminous coal and could potentially economically benefit the country.
BH3 and BH4 had horizons that are potentially mineable, and could be of use in coal conversion industries.
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26. Conclusions: U content
All coal seams studied had U content averages higher than the 2 ppm world average
BH3 has the highest U average
BH4, the UCZ in BH5 and the LCZ in BH5 all had an average Ur content less than 10 ppm.
U in the SFC samples was disseminated throughout the coal and carbonaceous shale.
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27. Conclusions: U detection
For all boreholes except BH5, U in the SFC samples was concentrated within the first 1m of the coal zone
U in the coal zones was generally restricted to a single layer, usually the highest in the local sequence, except in BH2 and the LCZ in BH5 where U mineralization was seen in multiple locations in the coal zone.
U was successfully leached from coal samples into solution.
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28. Future Work Analysis of the acid leached cake samples
Leaching using basic medium solutions.
Combustion of coal with U.
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29. Acknowledgements Prof N. J. Wagner
National Research Foundation:Thuthuka Fund
Council for Geoscience
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30. Thank you
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