PULVERIZED COAL CHAR COMBUSTION - THE EFFECT OF PARTICLE-SIZE ON BURNER PERFORMANCE

A two-dimensional, two-phase combustion model of pulverized coal char is presented in this paper. It is of particular importance to reveal t he controlling mechanisms, through prediction of the diffusion and rea ction rates and to evaluate the effect of initial coal-particle size o n the performance of the burner. The partial differential equations of conservation of mass, momentum, energy and chemical species are solve d taking into consideration turbulent flow, interphase mass and heat t ransfer, radiative heat transfer and operational conditions such as co al feed and primary and secondary air. The equations are integrated wi th the finite volume methods and are solved for the flow held, tempera ture field of gaseous and solid phases and the concentration of reacta nts and products. The results are compared with experimental data from the literature and the comparison is satisfactory. (C) 1998 Elsevier Science Ltd. All rights reserved.