Abstract:
Oxy-fuel combustion of solid fuel in a laboratory refers to the process of burning solid fuel in the
presence of oxygen enriched gas to produce heat and combustion products, with the aim of studying
combustion chemistry and/or emissions.
In this laboratory experiment, the combustion of pulverized high and low ash content coals and
biomasses from Kazakhstan was studied using a drop tube furnace. The ultimate and proximate
analysis was conducted beforehand to determine the composition of ash, moisture, and volatile matter
in the solid fuel. The combustion tests were carried out in both air (O2/N2) and oxy-fuel (O2/CO2)
environments. A 95cm long quartz tube was used as the Drop Tube and was kept at a temperature
between 900 to 1000 °C. The particle size of the fuels was averaged at 400 microns. High-resolution
images of the fuel conversion process in the Drop Tube were recorded to analyze the combustion
process. To achieve complete burn-out, the remaining oxygen concentration in the flue gas was
maintained at 5-7%. The temperature profile of each coal and biomass was taken during the heating
zone and used for the thermogravimetric analysis. The results of the experiment are expected to show
the flue gas emission at 900 to 1000°C for both air and oxy-fuel environments. These results will be
compared to determine the temperature that equates to that of compressed air.
Generally, this experiment will provide valuable insights into the combustion of high and low ash
content coals and biomasses gotten from Kazakhstan in different environments. The results will
inform future studies on the development of cleaner and more efficient combustion technologies. The
use of high-resolution images to study the fuel conversion process will also aid in the understanding
of the complex processes involved in combustion. By comparing the results obtained in air and oxyfuel
environments, it will be possible to determine which environment provides the most efficient
combustion for these fuels.