An improved blast furnace system for producing molten iron incorporating a
preheater to heat the cold blast air used to temper the hot blast
temperature is disclosed. The improved blast furnace system comprises a
blast furnace, a hot blast main for conveying a supply of hot blast to
the blast furnace, a plurality of stoves for heating a supply of cold
blast and generating the hot blast, a cold blast main for conveying a
supply of cold blast to the plurality of stoves, and at least one cold
blast preheater for heating a portion of the cold blast, that has been
diverted to the preheater, into heated air and the heated air is mixed
with the hot blast to temper the hot blast temperature.