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Instead of using pure oxygen in oxy-fuel combustion,oxy-enrichcombustion uses air to replace part of pure oxygen for coal combustion.Compared with oxy-fuel combustion, oxy-enrich combustion uses muchless pure oxygen, which may reduce the cost for CO2capturedue to the reduction of pure oxygen requirement. The thermo-gravimetrictechnique was used to study the combustion characteristics of threepulverized coals under oxy-enrich atmospheres. The results show thatboth the ignition and burnout temperatures of pulverized coals decreasewith the rise of oxygen concentration, while the combustibility index Sincreases gradually. Under the same oxygen concentration,the ignition and burnout temperatures in oxy-enrich combustion arelower than those in oxy-fuel combustion due to the different propertiesbetween N2and CO2. A fixed-bed reactor (FBR)was used to investigate the NO emissions of a coal sample at differentatmospheres. It is found that temperature has played an importantrole in NO releasing. With the increase of furnace temperature, thepeaks of NO release appear to occur early. For the tested coal, theconversion rates of fuel-N to NO in air are higher than those in oxy-fuelor oxy-enrich atmospheres, which may be due to the effect of CO2gasification. The conversion of fuel-N to NO appears to havesome complicated tendencies in oxy-enrich combustion, and some possiblereasons about this were discussed. [ABSTRACT FROM AUTHOR]