Long campaign cupola

To allow for long campaign operation the following measures need to be taken apply a more persistent refractory lining of the shaft, bottom and the hearth apply water cooling of the furnace wall this keeps the wall temperature low and thus prevents rapid wearing of the hearth lining 

A specific t)q)e of long campaign cupola is the cokeless cupola. This is discussed in Section 4.2.I.8. 

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Figure 2.11 Schematic representation of a long campaign cupola [150, ETSU, 1998]...

Hot blast cupolas are normally set up for long campaign operation, in order to minimise process switch overs and maintenance time and effort. 

Due to the absence of cokes (and CO), no latent heat is lost from the cokeless furnace system. Full heat recuperation from the flue-gas occurs in the shaft. In duplex configurations (for example in conjunction with an induction furnace), efficiencies in the range of 40 to 60 % may be obtained. Thermal efficiencies for coke fired cupolas vary between 25 % (cold blast) and 45 % (hot blast, long campaign). 

Installing post combustion on cold blast cupolas can be combined with a full retrofit to hot blast operation. In general, this choice is based on operational considerations. The characteristics of hot blast and long campaign furnaces are discussed in Section 2.4.1. 

ETSU (1998). "Long campaign hot-blast cupolas in iron foundries", GPCS366. 

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