The steam coal CBCR 182) is a medium volatile coal of high ash content, similar to many coals used for power generation. Gross samples of Lump coal were selected by hand picking from the coal seam. Initial size reduction to a particle size of approximately 12-15 mm was carried out by hand crushing using a manganese steel pestle and mortar. Further size reduction was carried out in two stages us 9 crushing rolls (chrome steel Cr 1.2 %; Mn 1.2 %) to yield a product of particle size approximately 1 mrr.. Final size reduction to approximately 0.2 mm particle size was carried out using either a cast-iron disc mill or a tungsten carbide centrifugal mill. This material was sized using standard wire mesh sieves corresponding to those specified in ISO 565 to provide a sample of particle size between 63 and 212 um. Particles of a size greater than 212 um were recrushed and returned to the bulk sample; material below 63 um in size was discarded. The sieving operation was carried out concurrently with the size reduction, all processes being carried out within the overall temperature interval of 17 - 20 °C. The yield of between 21 and 23 kg of the final product was stored under argen prior to sample division in a rotary sample divider. This operation yielded 20 sub-samples each of approximately 1 kg. Each sub-sample was protected from Oxidation by an argen atmosphere. The samples for analysis were transferred to glass ampoules, previously dried in nitrogen at 28 °C in a specialbox over dry Cblue) silica gel. The ampoules were filled by sample division by rotary sample divider and direct transfer to the ampoule.
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