Coal Preparation Expertise in Australia: In-Plant Issues and the Potential Impact of Broader Applications

摘要

Over the last decade, developments in fields including froth flotation and ash monitoring have been sensibly, and sometimes imaginatively, applied to improve Australian coal preparation practice. Remaining problem areas include degradation and fine coal dewatering; and further development of some instrument classes, or of calibration procedures, would be beneficial However, the greatest challenges for coal preparation in Australia lie in improving the ways in which existing equipment is applied and in improving the integration of all stages of mine production in order to achieve a suitable compromise between adequate investment returns and high utilisation of insitu resources. It is argued that existing techniques for density separation and for flotation of fines are well developed. In most situations they are capable of achieving yields within a few percent of the theoretical maximum which could be realised by sorting of individual particles according to ash content The fact that many plants fall short of that capability is attributed principally to 1. lack of understanding of preferred operating conditions for specific situations 2. inadequate maintenance 3. poor balancing of parallel circuits 4. biased feed distribution altering the performances of parallel circuits and 5. lack of appreciation of the sensitivity of yield to these factors. Many operations could achieve very great improvements in economic performance if metallurgical personnel could better share their expertise with mining and marketing personnel concerning matters such as 6. calculation of pit yields of coal (with proper correction for dilution) 7. simulation to quantify the economic advantages of adjusting mine plans and schedules to make particular coals available at appropriate times 8. assisting marketing personnel explore the options for altering the mix of products to maximise revenue, again utilising simulation procedures. Indirectly this is a plea to improve the capture and dissemination of specialist knowledge and to maintain or increase the availability, on site, of metallurgical expertise. With such assistance, and by making production and quality data readily available to those who can alter it, or whose functions are affected by it, more informed joint decisions can be made to the benefit of the entire operation. Such expertise has important applications in mining and marketing as well as in processing.