Output control from a sinter strand through the manipulation of strand speed; recent results of a simulation investigation

The sinter strand process consists of a moving grate onto which is loaded the raw material in the form of micropellets composed essentially of iron ore fines, coke, water and rejected sinter returned for reprocessing. The material is levelled to form a flat bed. The surface is ignited and under the influence of a suction fan, which draws air through the bed into a series of windboxes situated below the grate, a heatwave is drawn downwards through the bed. The heatwave first reaches the bottom of the bed at a point along the strand, known as the burnthrough position, which ideally should remain fixed near the output end of the strand. Although input-mix controls are used, the permeability of the material loaded onto the grate varies and consequently the burnthrough point shifts about its desired position and a proportion of the material unloaded from the strand is either undersintered or oversintered.