Coal Preparation » Gravity Separation
The objective of this project was to develop a machine to sort +4mm coal particles by density in the laboratory, to replace conventional heavy liquids fractionation (sink float analysis). The benefits were expected to include improved safety through the elimination of heavy liquids, reduced operating cost, and perhaps more accurate measurement.
The ACARP funding permitted a prototype machine ("Machine I") to be built and tested. This report describes the machine in detail. The principle is that of the gas pycnometer, incorporating systems to implement the measurement automatically on single particles without operator intervention. The machine comprises a single particle feeder, a weigher, a volume measuring apparatus, and mechanics for directing the measured particle to a particular sample bin depending on its calculated density. The operation is controlled by computer, and data acquired automatically and placed in an Excel spreadsheet for later use and evaluation.
After some development work, Machine I successfully demonstrated the proof of principle for each of the design elements. However some problems were encountered in the mechanical realisation of the principles. In view of the interest shown in the machine by a number of potential clients, it was decided to build a production prototype ("Machine 2") to address these problems and to test the requirements for manufacture. Full manufacturing drawings were prepared and the machine built under contract. This work was funded internally by JKTech, but the details of the work are included in this report for completeness. Progress was made in the development of the main system features, but Machine 2 was judged not to be an appropriate model for manufacture due to problems with single particle feeding and the sealing of the volume measurement pots.
After reviewing the sales potential and various business models, negotiations were successfully conducted with UltraSort Pty Ltd (a designated partner in the original ACARP project) to develop a production version and to commercialise the device. At the time of writing, this is the mechanism by which it is expected the technology will be made available to the market.