Study on Co-combustion Characteristics of Superfine Coal with Conventional Size Coal in O₂/CO₂ Atmosphere

Yuhang Zhang, Mingyan Gu, Biao Ma, Huaqiang Chu

Department of Metallurgy and resource, Anhui University of Technology, Ma’an shan, China.

DOI: 10.4236/epe.2013.54B007                

Abstract

The pulverized coal combustion in O₂/CO₂ atmosphere is one of the promising new technologies which can reduce the emission of carbon dioxide and NOx. In this study, the combustion behaviors of different mixing ratio of Shenhua coal with 20 μm and 74 μm particle size in the O₂/CO₂ atmosphere and air atmosphere were studied by using a thermal-gravimetric analyzer. The combustion characteristics such as ignition and burnout behavior were investigated in the temperature from 20℃ to 850℃. The influence of mixing ratio on combustion characteristics was conduced. The results obtained showed that the ignition temperature of the two kinds of particle size in O₂/CO₂ atmosphere is higher than in the air, while the activation energy in O₂/CO₂ atmosphere is lower. With the increasing ratio of 20 μm superfine pulverized coals, the ignition temperature and the activation energy decreased, while the DTG peak value increased, the maximum burning rate position advanced. There were three trends for the ignition temperature curve with the increasing of superfine coal ratio: the ignition of the mixed coal decreased rapidly, then changed less, at last reduced quickly.

Keywords

Coal Particle Size; Co-combustion; Thermo-gravimetric; Heat of Combustion

Conflicts of Interest

The authors declare no conflicts of interest.

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