1999 Volume 39 Issue 4 Pages 319-328
The compuer model, which could simulate the transport phenomena of the COREX melter-gasifier considering the pyrolysis behavior of raw coal, was developed. This model was made up of 192 ordinary differential equations for gas and solid phases in the 1-dimensional fixed bed part and balance equations for gas phase in the combustion zone and the freeboard zone of 0-dimensional assumption. This coupled non-linear equations are calculated by the LSODE packages and Gibbs free energy minimization method. The effluent gas temperature showed good agreement with the operational data. The temperature of the gas was decreased linearly with the distance from the combustion zone. The predicted melting position of ore and flux mixture was 2.0 m high from the combustion zone. CO was mainly generated in the combustion zone and H2 was mainly produced during the devolatilization of coal. The fixed bed in the melter-gasifier could be divided into four distinct zones. Each zone has its own reaction characteristics such as heating zone, primary pyrolysis zone, secondary pyrolysis zone and gasification zone.