Study on combustion characteristics of young lignite in mixed O2／CO2 atmosphere

Abstract

In order to study the influence of the change of oxygen concentration on combustion characteristics of coal, in the simultaneous thermal analysis was carried out on different oxygen concentration of Xiaolongtan young lignite (21%, 30%, 50%, and 80%) combustion characteristics experiments under the mixed O2/CO2 atmosphere. Determined the combustion characteristics of pulverized coal with different oxygen concentration. Experimental results show that, with the increase of oxygen concentration, the DTG curve of pulverized coal shifted towards lower temperature range, the ignition temperature and burnout temperature of coal sample decreased, combustion time shorten, burning speed accelerated, flammability index increased. Meanwhile, at different heating rates, with the increase of heating rate, the temperature of the same burnout rate increase, with the increase of temperature, the coal sample’s burnout rate increased. With the decrease of pulverized coal’s particle size, lignite ignition temperature and burnout temperature are both decreased, at the same time burnout time also shorten. When the oxygen concentration is larger than 30%, pulverized coal’s combustion characteristic parameter change slowly. Thus, industry, considers the cost of oxygen-enriched, it can control oxygen concentration at 30%.