The Variability of Mercury Content in Bituminous Coal Seams in the Coal Basins in Poland

The mercury content in bituminous coal in Poland varies depending on the coal basin. The highest of its concentrations are recorded in the Lower Silesian Coal Basin where this may be the result of the volcanic activity reported there. A much lower average of Hg content was recorded in Lublin and the Upper Silesian Coal Basins (LCB and USCB), although it was higher in the former. A higher mercury concentration in the LCB is probably related to the zone of supposed deep disturbances, named the Karpinsky lineament. Most published works present the data on the mercury content in the bulk of mined coal. The preliminary assessment of mercury content in coal seams indicates that it varies considerably between and within them. It is bound to the presence of arsenic-bearing iron sulfides. Concentration of mercury in small zones of limited extent suggests it was introduced by migrating fluids. The knowledge of mercury content distribution in coal seams would improve the prediction of its content in the mined coal and allow better management of produced coal quality with the aim of reducing mercury emission to the atmosphere as a result of coal combustion.