Developing/Modifying Coal Grinding Procedures and Equipment to Produce Predictable Size Distributions During Coal Preparation. Annual Progress Report, October 1977-December 1978

摘要

The mechanical properties analyses of the project coals were completed. As found by other researchers, there was no property which correlated with the grindability of the project coals. The mechanistic models for the three dry grinding systems were derived and are undergoing validation. Two special studies were completed. The first examined the grinding of coal in oil. The results were presented in an invited technical paper before the 1st International Coal Oil Mixture Conference. This is only the first of many technical papers that will evolve from this study. The second special study involved a comparison between two types of grinding media - the conventional ball and the cylpeb, a type of equidistant rod. All four coal grinding circuits - air swept ball mill; ball and race mill; hammer mill; wet overflow ball mill - were operated to generate data to validate the mechanistic models. The coal produced during these tests was made available to other DOE projects requesting material. In addition, the grinding facilities were used in support of coal grinding process information for several DOE demonstration projects. (ERA citation 05:002452)