Numerical Simulation of Coal and Natural Gas Co-Combustion in a Rotary Lime Kiln with Different Types of Coal

In order to improve the coal combustion condition, this essay based on an active lime rotary kiln in Wulongquan Limestone Mine of WISCO, focuses on the multifuel combustion of the coal together with natural gas by means of numerical simulation. To discuss the relationship of the flames with the coal composition, the cases with four different qualities of coal were compared. The gas phase is expressed with ¿-¿ two-equation turbulence model; the discrete phase with particle track model; the combustion with non-premixed model; and the radiation with PI radiation model. The results show that the volatile fraction content of coal has important impact on the early stage of the coal combustion; the natural gas burns out quickly to heat the coal and the gas flow.