(443f) Char Oxidation Characteristics of Ashless Coal Particles Burning in a Drop Tube Furnace

Recently, it is essential to develop alternative energy as the fuel in the power plant in the world which is faced with energy crisis because of economic constraints. The ashless coal, one of cleanest fuel, is known to contain relatively low ash and high calorific value, which could increase combustion efficiency and reduce carbon dioxide emission. The combustion processes of the ashless coal char were examined to understand how it could influence the performance of a pulverized coal-fired boiler. In this study, an experiment has been conducted on the kinetic analysis for single particle of an ashless coal char burning at different temperatures of drop tube furnace (DTF). Temperature distributions of single particles during the oxidation process were monitored by a two-color pyrometer mounted on the top of the furnace. An amount of char mass reacted during char oxidation is calculated from the flue gas measurement. The char oxidation kinetic parameters(A, E) of the ashless coal with determined char oxidation rate and the reaction rate coefficient was also obtained using an n-th order Arrhenius model. The results show the oxidation reactivity of the ashless coal was comparable with those of the conventional coals which could justify the use of the ashless coal in the real utility boiler.