Title :
Sensing pulverized material mixture proportions by resonant cavity measurements
Author :
Nelson, Stuart O. ; Kraszewski, Andrzej W.
Author_Institution :
Agric. Res. Service, Russell Res. Center, Athens, GA, USA
fDate :
10/1/1998 12:00:00 AM
Abstract :
Based on differences in the permittivity of coal and limestone rock, a resonant cavity measurement technique is presented for the rapid determination of the proportions of coal and limestone in powdered mixtures. The ratio of the resonant frequency shift and the change in the transmission factor when mixed coal and limestone samples are inserted into the cavity provides a means for estimating the percentage of coal in the mixture relatively independent of the bulk density of the mixture. The technique might be developed for rapid tests of dust in coal mines to determine whether the 65% noncombustible content requirement is being met for prevention of coal mine explosions
Keywords :
cavity resonators; coal; dust; microwave measurement; mining; permittivity measurement; pulverised fuels; coal mine explosions; coal permittivity; limestone rock permittivity; noncombustible content requirement; pulverized material mixture proportions determination; rapid dust tests; resonant cavity measurements; resonant frequency shift; transmission factor; Dielectric constant; Dielectric loss measurement; Dielectric losses; Dielectric materials; Dielectric measurements; Equations; Measurement techniques; Permittivity measurement; Resonance; Resonant frequency;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
