Method to produce cement clinker using high sulfur content fuel

In a method for producing in a cement plant cement clinker from a conventional feedstock raw mixture, which method comprises the steps of:

• feeding the raw mixture to said plant;
• preheating the raw mixture;
• calcining the preheated raw mixture;
• sintering of the calcinated raw mixture to produce cement clinker;
• and
• cooling the cement clinker;
• modifying the method to permit use of a fuel having a high sulfur content as a heat source for at least one of preheating, calcining, decarbonating and sintering of the raw mixture while preventing process-inhibiting build up of sulfur compound encrustations within said plant by:
• preparing a modified raw mixture before the feeding step based on the Lime Saturation Factor (LSF), the Silica Module (SM) and the Alumina Module (AM) and the fineness of the raw mixture, wherein the LSF is up to 1, the SM is between 2 and 3.5, the AM is between 0 and 3, and the fineness is on the order of mesh size no. 200, which in combination are adequate to reduce the conventional temperature in the clinkering step by more or less 100° C., from about 1500-1450° C. down to about 1400-1350° C., while maintaining essentially the same low percent of free CaO;
• and
• controlling the residence time of the calcinated mixture, the clinkering temperature and the maintenance of oxidizing conditions at the kiln inlet at an excess of 4% to 5% during the clinkering step.