Mechanistic Model for the Understanding of Sole Heated Ovens

A method for modelling sole heated ovens (SHO) based on fundamentals of heat transfer, particle dilatation and gas flow has been developed. It has been successfully applied to the Sapozhnikov SHO and University of Newcastle (UoN) SHO. The model estimates both the shrinkage and plastic layer thickness. It uses parameters determined from Ruhr dilatometer measurements to characterise the plastic properties of the coal being studied and an adjustable parameter to characterise the relative permeability of gas flow along the wall of the oven compared with through the bed.

Model predictions have been compared against Sapozhnikov results and the UoN sole heated oven (SHO). Experimentally the effect of particle size, confining pressure and bed height on results were studied.

The model allows us to investigate the effect of the different SHO design and operating parameters on the results. Key factors affecting the final results are:

· The method of packing the SHO and the impact of this on the leakage of gas up the wall of the oven. The packing could be affected by factors as the packing bulk density as well as mechanical aspects of the packing;

· Particle size;

· Confining pressure.

The model also allows us to examine the fundamental phenomena occurring inside the SHO to the phenomena expected inside a coke oven. The wall effect on gas flow in the SHO appears to be significant and is likely to cause issues with using the SHO results to fully represent the behaviour in coke ovens.

The success of the model builds upon the dilatometer model developed in a previous ACARP project, and provides confidence that the approach can be extended to modelling of behaviour in a coke oven, which is the aim of a new ACARP project.