Coal quality monitoring
Work was undertaken to advance the development and application of on-line coal quality monitoring. In particular, factors affecting the application and performance of ash and moisture measurement were studied. Ash content measurements, using low energy gamma radiation, demonstrated that the lower limit of measurement accuracy is mainly controlled by variations in ash composition. On-belt trials of two commercial ash monitors showed the potential for significant errors if a non-representative portion of the coal stream is analysed. A previously developed, single frequency, microwave moisture meter was improved and a new varying frequency moisture meter, which is less sensitive to the disturbing influences of coal type, particle size and sample geometry, was developed. A new type of capacitance moisture meter was designed and built. Reasonable accuracy was obtainable but some technical problems remained. Nuclear magnetic resonance techniques for measuring moisture in coal were found to have reasonable accuracy with small volume samples. Use of the technique for large scale on-stream monitoring was not considered worthwhile because of the high capital cost of equipment. On-line neutron gamma analysers are capable of measuring most of the quality parameters of coal to a useful degree of accuracy, but applications are again restricted by high capital cost.
Bibliographic Reference: EUR 13351 EN (1991) 306 pp., MF, ECU 16
Record Number: 199110181 / Last updated on: 1994-12-02
Original language: en
Available languages: en