Method of heating a continuously charged furnace particularly for steel-making products, and continuously charged heating furnace

#1. Field of the Invention

#The invention relates to the heating of continuously charged furnaces, and in particular to a method of heating furnaces intended to raise to a high temperature, as uniformly as possible, steel-making products which may have a large cross section, for example slabs, billets, blooms or ingots, and to a heating (or reheat) furnace of this kind.

#2. Description of the Related Art

#Other features and advantages of the invention will emerge from the description which will follow of some methods and forms of embodiment of the invention which are given by way of non-limiting examples.

#FIG. 1 illustrates the heat balance in a conventional furnace depicted very diagrammatically in longitudinal section, and

#FIG. 2 illustrates the heat balance in a furnace according to the invention, depicted very diagrammatically in longitudinal section.

#The conventional continuously charged reheat furnace depicted very diagrammatically in FIG. 1, by means of which steel-making products are raised to a high temperature, includes an internal space in which the steel-making products 1 are made to pass from a charging end 2 to a discharging end 3.

#This internal space includes a heating zone 4 equipped with heating air/fuel burners symbolized as 41, on the discharge end side, at which burners, as a result of combustion, high-temperature (of the order of 1200° C.) flue gases are released; the heating zone 4 may itself be subdivided into several zones such as, from the upstream end in the downstream direction, a preheat zone, a heating zone proper, and an equalization zone. The internal space of the furnace also includes a burner-free so-called recuperation or drainage zone 5 in which the hot flue gases released at the burners are circulated so as to recover some of their energy before recuperating them themselves as they leave the furnace in the discharge end region 2 thereof so as to reheat the air sent to the burners.

#The term “air/fuel burners” is understood to mean not only conventional air/fuel burners but also air/fuel burners doped with oxygen but nonetheless releasing a significant volume of flue gases typical of combustion using air.