The behaviour of Kolubara and Kostolac lignite during devolatilisation process: A petrographical approach

Abstract

The devolatilization process is the initial step in the coal combustion. Devolatilization research was performed on a wire-mesh reactor in inert gas, at the atmospheric pressure. Two different sets of feed coal samples of various particle diameters (0.50<х<1.00 mm; 0.25<x<0.50 mm; 0.1<x<0.25 mm; x<0.1 mm) from the Kolubara and Kostolac mines were used for research. Lignite samples were spread in a thin layer a few particles thick, over electrically heated stainless steel wire mesh and rapidly heated at four different temperature stages (300oC, 500oC, 700oC, 900oC). Maceral analysis and rank deternination were performed on 32 combustion residues and 8 lignite samples following the classification developed by ICCP for lignite, bituminous coal and coal chars.