A simulation study of coal blending control using a fuzzy logic ash monitor

On-line nuclear meters have been in use in the coal industry for many years. They have been utilised for coal quality monitoring, in the control systems for coal blending, or for separating coals in the heavy media separation process. Their operation is based on the scattering or the absorption of incident gamma radiation, and the derived density or ash value is the result of a time-averaged measurement. The simulation analysis shows that the best results are given by the monitors in which the time of measurement is variable and adapts to changes of the input signal. An example of a coal blending control system which stabilises coal quality of the blend with the use of the fuzzy logic ash monitor has been analysed.