Microwave Technique for the On-Line Determination of Moisture in Coal
Source abstract
Abstract
An investigation has been carried out to compare the suitability of microwave transmission techniques, based on the determination of attenuation/mass-per-unit-area, phase shift/mass-per-unit-area and attenuation/phase shift for the on-belt measurement of moisture in coal. Preliminary measurements were made on a range of Australian coals packed in waveguide sections.A prototype non-contacting microwave gauge has been designed for the on-belt measurement of moisture in coal, in which phase shift and attenuation are determined using an 8- port junction. Measurements on a range of coals in layers of 50 to 250 mm thickness and 0 to 15 wt% moisture indicate that moisture can be measured to better than 0.37 wt%, from a determination of phase shift/mass-per-unit-area, using this gauge. The influence of sample packing density, ash content, and material temperature on measurement accuracy has been determined.
Source: openalex_inverted_index · Quality: baseline
Research context
OpenAlex topics: Acoustic Wave Resonator Technologies · Microwave and Dielectric Measurement Techniques · Geophysical Methods and Applications
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (5)
Show source-provided references
1. Cutmore, N.G., Rafter, P.T., Abernethy, D.A., and Millen, M.J. 1988. Plant trial of an under-belt capacitance and gamma-ray backscatter gauge for on-belt determination of moisture in coal. Proc. Aust. Inst. MM. Metall. (in press).
2. Fauth, G. 1982. The application of infrared-reflectance techniques to the monitoring of moisture in coal preparation plants. In Proc. Symp. Instr. Control for Fossil Energy Processes, ANL, Argonne Ill., 71–84.
3. Hoer, C.A. 1975. Using six-port and eight-port junctions to measure active and passive circuit parameters. NBS Technical Note 673.10.6028/NBS.TN.673 ↗
4. Klein, A. 1984. Microwave determination of moisture compared with capacitive, infrared and conductive measurement methods. Comparison of on-line measurements at coal preparation plants. In Proc. 14th European Microwave Conf., Liege: 661–666.
5. Nelson, S.O., Beck-Montgomery, S.R., Fanslow, G.E., and Bluhm, D.D. 1981. Frequency dependence of the dielectric properties of coal - Part II. J. Microwave Power 16 (3 & 4): 319–326.10.1080/16070658.1981.11689255 ↗