MACERAL MICROLITHOTYPE PARTITIONING THROUGH TRIBOELECTROSTATIC DRY COAL CLEANING

Three eastern Kentucky and two Illinois Basin coals were tested in a b ench scale triboelectrostatic separation unit. The three eastern Kentu cky samples provided a rank series of petrographically comparable coal s. The Illinois Basin bituminous coals were lower rank and had high vi trinite (similar to 80%) and sulfur contents in comparison to the othe r three coals. Triboelectrostatic beneficiation provides efficient mac eral and mineral partitioning in the high volatile A and B bituminous coals tested, with vitrinite, as vitrite and vitrinite-enriched microl ithotypes, reporting to the clean fractions and the inertinites, lipti nites, and minerals reporting to the tails. The high volatile C bitumi nous Springfield coal had a lower separation efficiency than the petro graphically similar, but higher rank, Herrin coal. The decreased separ ation efficiency in the behavior of the Springfield coal may be a resp onse to its higher moisture content. Compared to bench-scale fuel oil agglomeration of some of the same coals, triboelectrostatic separation provides clearer partitioning of mineral matter, sulfur, and macerals . (C) 1997 Elsevier Science B.V.