A Provisional Basinal Study of the Waterberg-karoo, South Africa
R1500,00
Description
Related Products
Development of a Horizontal Winnower for the Beneficiation of Fine Coal
Proof of concept work on dry beneficiation of minus 6 mm coal, combining airflow modelling and simulation with a laboratory winnowing box, for plants short of process water.
What this report foundHorizontal air winnowing separated fine coal by particle size and density in laboratory experiments, supported by equation of motion modelling and...
R1500,00
Horizontal air winnowing separated fine coal by particle size and density in laboratory experiments, supported by equation of motion modelling and computational fluid dynamics. Modelling indicated that a chamber 0.6 m high and 1 m long is sufficient to displace any minus 6 mm particle at air velocities of 10 to 30 m/s.
Verification of the New Coal Pillar Strength Formula and Investigations Into the Prediction of Pillar Life in Witbank and Highveld Coalfields
2004
Covers pillar load and strength estimation, the limits of tributary area theory, and the extraction gains available from revised strength formulae, for rock engineers designing bord and pillar workings.
What this report foundLaboratory testing showed coal specimen strength rising linearly with width to height ratio and falling exponentially with specimen size, the size effect...
R1500,00
Laboratory testing showed coal specimen strength rising linearly with width to height ratio and falling exponentially with specimen size, the size effect becoming insignificant beyond about 2 m diameter. The slope of that relationship was the same for coals from different mines, while the intercept varied with specimen size.
A Preliminary Investigation Into the Geotechnical Interpretation of Geophysical Logs
2004
Compares a full suite of downhole sondes against geotechnical core logging over the 5 m above three coal seams, for geologists and rock engineers assessing roof conditions.
What this report foundGeophysical logging of boreholes above three Witbank seams identified clay rich matrices, stiffness changes, bedding planes and the principal stress direction...
R1500,00
Geophysical logging of boreholes above three Witbank seams identified clay rich matrices, stiffness changes, bedding planes and the principal stress direction, and picked up fractures in 30 to 75 per cent of cases. Core logging found most of the same features faster, so routine use was not recommended unless stiffness and stress direction matter.