Experimental determination of reaction kinetics for the release of chlorine and sulphur species and for the conversion of these species in the gas phase
Sulfur, chlorine and nitrogen present in coals can form various corrosive combustion products and pollutants. Due to the flue gas recirculation, Oxy-Fuel combustion results higher concentration of these corrosive (and all other) combustion gases. In Oxyflame project A3, models for the prediction of sulfur, chlorine and nitrogen species are developed.
Experiments are performed with an entrained flow reactor in which pulverized fuel is heated up to target temperature almost immediately, achieving heating rates equivalent to large-scale boilers. The reaction progress is analyzed by taking gas and solid samples after different residence times. Kinetics are determined using thermogravimetric analysis.
Global reaction mechanisms for the release of chlorine, sulfur and nitrogen species during pyrolysis and char burnout will be derived from the experimental data. The influence of fuel type, heating rate, temperature and gas atmosphere (conventional and Oxy-Fuel combustion) on species release will be evaluated.