Composition and properties of North Bohemian coals IVANA SYKOROV, ~ l, JAROSLAV (~ERN' ~ 2,

Abstract: This work presents the mean chemical, micropetrographic, surface and other characteristics of coal seams from western, central, and eastern parts of the North Bohemian brown coal basin. Attention was especially paid to the elemental composition, ash content, content and forms of sulphur, occurrence of syngenetic and epigenetic sulphides, maceral composition, and degree of gelification and decomposition of components in the huminite maceral group. Some other coal characteristics were also assessed, such as pore texture, extractability and solvent swelling of the coals. The coals examined were huminitic with a variable xylite and detrite content. Huminite reflectance varied between 0.33 and 0.39%. Substantial differences in pore texture of the coals were found in the range of meso- and macropores. These differences largely affected the extractability of the North Bohemian coals. The coals also exhibited extremely high swelling ratios in basic solvents, such as pyridine. The North Bohemian basin is the most impor-tant brown coal basin in the Czech Republic. It is situated south of the Kru~n6 Hory mountains and has an area of approximately 1400 km 2. The main coal seam belongs to the Miocene Most Formation. The only mineable seam in the North Bohemia coal basin is the main coal seam with an average thickness of 30 m and maximum i,_.r-'/ % ~,~ L S ' '73.75 "bs7.+f&apos