Experimental and numerical study of pulverized lignite combustion in air and oxy-fuel conditions. Part 1: Experimental setup and the mathematical model

摘要

The present paper presents the setup used to carry out experiments of pulverized lignite combustion in air and in oxy conditions involving 25% and 30% O_2 mole fraction in the gas mixture. The experiments were carried out in laboratory conditions using a drop tube furnace operating at temperature of 1200°C. Next, a complete combustion model of pulverized coal has been presented. The model takes into account all key processes and phenomena occurring during pulverized coal combustion. A general single-film model has been introduced and used to define rates of gas-solid reactions. The gas phase reaction rates have been defined by the Magnussen formula developed for non-premixed flames. The model implemented into Ansys Fluent code has been used to simulate pulverized lignite combustion carried out in the experimental part of this study.