Method of producing steam and calcined raw meal

Abstract

A method of producing a calcined raw meal and of producing additional steam in an existing steam generator comprises the following steps: pulverized raw meal, hydrocarbon, primary air and secondary air are fed to a calciner system (60), wherein the raw meal is calcined in a temperature range between 850° C. and 950° C., the calcined raw meal is separated from the calciner flue gases at the exit of the calciner system, the calcined raw meal is directed through a cooler (70), in which it exchanges its heat with the secondary air, the calciner exhaust gases are directed in the gas path of the backpass of the steam generator (1) at an appropriate temperature window and are used for steam production. The raw meal consists mainly of limestone (CaCO3) and the calcined material is mainly lime (CaO). The fuel feed (4) to the steam generator (1) is reduced during introduction of the exhaust gases into its backpass.

Dependencies are inferred from the claim text.