Resources from coal beneficiation waste: Chemistry and petrology of the Ayrshire coal tailings ponds, Chandler, Indiana

Abstract

Tailings (refuse) material, a mixture of fine coal and rock from the beneficiation of high volatile C bituminous Pennsylvanian Illinois Basin coals, was recovered from the tailings pond near the site of the former preparation plant. The material has widely varying concentrations of some elements, such as Sn, which might reflect non-coal contamination of the product stream at any point from mining and beneficiation of the coal to disposal of the waste product. The rare earth elements have a strong M-type enrichment. Concentration of the rare earths is below what would normally be considered to be an economic grade. The mix of coal and REE-lean rock, though, implies that the resource must be examined with an eye towards the recovery of critical elements, not just for the reconnaissance bulk characterization, as was done here. Despite the low concentration of REE and other critical elements, factors such as the ease of moving the comminuted, near-surface material and its proximity to highway, rail, and river transport implies that such resources must be carefully examined; not simply dismissed because the grade is below a cutoff level developed for coal, not mixed rock + coal.