The paper presents the results of the mechanical, electrical, CCSEM and XRD measurements of hard coal, conducted in simulated conditions of sintering in atmospheres of O2/CO2,. The changes of the coal ash resistivity are correlated with the content of the oxides and with the sintering temperature determined by the mechanical test and Leitz method. The SEM-EDS analysis was conducted for deposits on the probe. The changes of the measured ash samples, observed during sintering process in O2/CO2 atmosphere, were discussed in the ash microstructure point of view.

The paper presents results of coal behaviour during combustion in oxy-fuel atmosphere. The experiment was performed using 3 meter long Entrained Flow Reactor and 1 meter long Drop Tube Reactor. Three hard coals and two lignites were analysed in order to investigate NOx, SO2 emission and fly ash burnout. The measurements were performed along and at the outlet of a combustion chamber for one- and two - stage combustion. In the second stage of the experiment, kinetic parameters for nitrogen evolution during combustion in oxy - fuel and air were calculated and the division of nitrogen into the volatile matter and the char was measured. The conducted experiment showed that emissions in oxy - fuel are lower than those in air.