Combustion characteristics of coal briquettes. 2. Reaction kinetics

Altun, Naci Emre
Hicyilmaz, C
Bagci, AS
This study comprises the influence of the major briquetting parameters, such as binder type and amount of binder and water addition, on the combustion kinetics of the coal briquettes. In this manner, briquettes that have been prepared with different organic agents (molasses, carboxyl methyl cellulose, Peridur XC3, Peridur C10, and sulfide liquor) and inorganic agents (cement and bentonite) were combusted in a reaction cell assembly that operated in coordination with a continuous gas analyzer. Moreover, not only was the addition amount of the binder providing the most favorable reaction kinetics with the lowest activation energy varied, but the quantity of the water added was also varied with fractions of 5%, 10%, and 15% (by mass), to determine the possible effect of variations in binder and water quantities. The influence of the parameters of concern on the combustion kinetics of the coal briquettes was investigated using the effluent gas analysis method and was interpreted by an Arrhenius kinetic model that operated on the basis of the changes in the amounts of CO and CO2 that were evolved and the amount Of O-2 gases that were consumed, as a function of temperature and time at three different pressure levels: 25, 50, and 75 psig. At the end of experiments, the activation energy and Arrhenius constant for each run were calculated, and it was observed that the liability of the coal briquettes to ignite and the efficiency and effectiveness of the combustion reaction were considerably affected both by the binder type used and by the amount of binding agent and water addition.