A new the pig iron and molten slag level meter for the blast furnace was developed to realize stable furnace operation. One
type of the unstable operation is rise of the pig iron and molten slag level, which causes poor furnace conditions. In the worst
case, this can cause serious trouble with a large decrease in production.
In this proceeding, the new technique is described, which is measuring the liquid level in a blast furnace using the very low
electrical resistance measurement in the lower part of a blast furnace, which contains pig iron and molten slag. The four point
contact method was adopted, and a pseudo random signal as a current pattern to improve S/N ratio. This technique makes it
possible to detect rise or fall of the liquid level. An online test confi rmed that the level meter could predict deterioration of the
furnace condition before other sensors can.
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