Physico-chemical investigation of stone coals of «Karazhyra» field

Abstract

Results of physico-chemical research of stone coals from the Karazhyra field presents in this work. The following technical indicators of coals were studied: moisture, ash, yield of volatile component, sulfur content, elemental composition, heat capacity, morphology and particle size. The results of the technical analysis indicate low ash and moisture. X-ray fluorescence spectral analysis indicates the presence of rare earth metals in the composition of coal. The surface morphology and particle size of coal samples were characterized by scanning electron microscopy. Results show that the surface is heterogeneous with areas characterized by a dense structure and porous texture. On the surface also observed micron-sized clusters. The average fraction size is 0–300 millimeters. Areas with a porous texture has a corrugated surface with open slit-like and tunnellike exits forming a system of pores with a size 2–10 microns. Thermal stability was determined by differential scanning calorimetry. On the sample surface was spectroscopically identified oxygen-containing and nitrogen-containing groups. Coal has a relatively high heat of combustion, a high yield of volatile compounds, characterized by a relatively low ash value, moisture, low sulfur and nitrogen content. Demonstrated the possibility of using the Karazhyra field coals in almost all branches of the national economy.