From in situ coal to the final coal product: a case study of the Danville Coal Member (Indiana)

A surface coal mine operation and preparation plant in southwestern Indiana was sampled to examine variations in coal quality and coal petrography par ameters for the Danville Coal Member of the Dugger Formation (Pennsylvanian -Desmoinesian, Westphalian D). Representative samples from in situ coal, pr eparation plant feeds, and a final coal product were collected in order to compare coal quality, coal petrography, trace element concentrations, and a sh chemistry of the coal to those of the product. Coal quality parameters o f the in situ samples and various feeds, coarse refuse, and final product w ere variable. The quality of the final coal product was best predicted by t he coal quality of the dean coal feed (from the middle portions of the seam ). Some trace element contents, especially lead and arsenic, varied between the coal feeds and the product. Lead contents increased in the feeds and p roduct compared to the channel sample of the raw coal, possibly due to cont amination in the handling process. (C) 1999 Elsevier Science B.V. All right s reserved.