Some Results of Studies of the Correlation Between the Petrographic Composition of Brown Coals from Turow and Their Briquetting Properties

摘要

Petrographic-chemical and briquetting studies led to the following conclusions: (1) The coal seam being exploited, which basically consists of three separate and specific coal strata is characterized by wide differences in the petrographic composition of the coal over the vertical profile. The upper layers are richer in xylites and clayey interlayers. The middle section is characterized by the presence of bituminous coal layers and clayey interlayers. The floor layers include bituminous coal consisting of normal xylites with insertions of woody structural xylites and smudge coal. (2) Microscopic examination of the samples of coal indicated a high degree of gelling of the organic constituents. The concentration of gelled xylinites having characteristics similar to those of doplerite is appreciable in all coal strata. Egzynite (exinite)-protobituminous substances are present in an amount of 4 to 18% throughout the entire vertical profile of the investigated coal strata. They consist mainly of resinous substances. (3) Chemical analysis of the coal confirms the results of the microscopic examination and does not indicate local accumulations of egzynite (exinite)-protobituminous substances, but there was higher concentration of proto-tar due to bituminization of lignin-cellulose materials under specific anaerobic conditions. The carbon concentration is typical of low conversion and gelled brown coals. (4) Evaluation of the compression strength of the briquettes made from the coal under investigation and determination of their water absorption indicates that it is possible to obtain briquettes of suitable mechanical strength from coal of low ash content, but the resistance of such briquettes to water will be low because of the high content of gel, i.e., doplerite (gelled xylinite). 3 refs., 1 fig., 3 tabs. (ERA citation 11:021908)