Oxy-fuel combustion is one of the most promising CO2 capture technologies. The oxygen-enriched combustion of pulverized coal was simulated in a thermogravimetric analyzer coupled with a mass spectrometry (TG-MS) in order to understand the ignition model and the generation characteristics of pollutants during combustion. Bituminous and anthracite standard coals were selected as the samples. The tests were done with oxygen volume fractions of 21%

30% and 50% with two kinds of atmospheres (O2/Ar and O2/CO2). In the O2/CO2 atmosphere

both of the ignition temperature and burnout temperature were lower

the combustion rate was improved

the combustion time was shortened

and the combustion performance was much better. Based on the TG/DTG curves

the ignition models of pulverized coal were judged. It was showed that the heterogeneous ignition of pulverized coal happened in O2/Ar atmosphere

while the homogeneous ignition occurred in O2/CO2 atmosphere. Also

the activation energy and pre-exponential factor of coal combustion were calculated by Coats-Redfern method. When the oxygen volume fraction was above 30%

the apparent activation energy of the anthracite coal combustion in O2/CO2 atmosphere was significantly lower than that in O2/Ar atmosphere

indicating an obvious improvement in reactivity. In the same reaction conditions

the activation energy of bituminous coal was lower than that of anthracite coal

and the former was more prone to ignition and combustion

showing better combustion performance. In the atmosphere of O2/CO2

the generation of CO and volatile-NO was promoted

and the formation temperature was lower than in O2/Ar atmosphere. Meanwhile

the abundant CO would lead to NO reduction reaction.