Vast reserves of brown coal exist in Australia. However, the high moisture contents of these brown coals pose challenges for existing and potential users. An obvious solution isto remove the moisture by drying. A drying technique that is currently receivingincreased focus is superheated steam drying which, relative to conventional air dryingtechniques, provides a number of significant advantages including increased efficiency,reduced fire or explosion risks, faster drying rates and no particulate or odorousemissions. In the current paper, the drying of brown coal in a pilot scale superheatedsteam rotary dryer developed by Keith Engineering is investigated. It is illustrated thatthe dryer is able to significantly reduce the moisture content of Australian brown coals,with moisture reductions of up to ninety per cent achievable. Through a statisticallydesigned series of tests, the parameters affecting the drying performance are investigated.It is demonstrated that the final moisture content is particularly dependent on the steamtemperature and coal feed rate while the drum rotational rate has a less significant effect.
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