EFFECTS OF THERMOPHYSICAL PROPERTIES OF PACKED COAL BED ON COKING BEHAVIOR IN OVEN CHAMBER

The internal stress of a lump coke in a coke oven chamber is analyzed using a creep model, which can represent a deformation behavior of the lump coke. The thermal stress analysis, which has been previously dev eloped by authors to estimate the stress distribution within the lump coke in the laboratory scale oven, is improved with considering the cr eep characteristics of the plastic and semi-coke layers, dilatation of the plastic layer and the pyrolytic reaction fraction dependence of t hermophysical properties. The effects of the above-mentioned models on the stress distribution and deformation behavior within the lump coke are discussed in this study. The calculated stress distribution and d eformation behavior within the lump coke lead to the following conclus ion: 1) The pyrolytic reaction fraction dependence of the thermophysic al properties influences on the results of the heat transfer within th e lump coke and the heating rate at the region near the coke oven cent er is estimated to be higher than one calculated with the properties w hich are measured in the constant heating rate condition. 2) The y-dir ectional tensile stress at the center of the lump coke, which is calcu lated with the creep analysis, is half of the one of the elastic analy sis. 3) The clearance which is defined as a distance between heated wa ll and lump coke is smaller because of considering the dilatation of t he plastic layer. 4) The model used in this study can more accurately predict the formation/propagation of transverse fissure within the lum p coke. Thus the creep model would be an effective tool to investigate the coking process.