Clinker temperature curve

Typical temperature curves for the clinker, secondary air and kiln shell are shown in Fig. 45. 

Alite may be expected to form in clinkers as the R polymorph, and belite as u l, ot n or a, according to the temperature. Chromy (C9) and Hofmanner (H21) discussed DTA curves of raw meals (Fig. 3.4). The main exotherm is due to belite formation, and the main endotherm to melting. A small... 

Major influences on the kinetic curve of a cement include the phase composition of the clinker, the particle size distribution of the cement and the RH and temperature regimes during curing. Other influences include the w/c ratio, the content and distribution of admixtures, including gypsum, the reactivities of individual clinker phases and probably others, such as the microstructures of the clinker and of the cement particles. 

Because of the considerable effect that the secondary rate has upon the clinker entry temperature and the calculated efficiency of the cooler, the relevant values are, for the sake of better comparability, sometimes converted to equal secondary air rate and, with the aid of the cooling curves determined, also to equal clinker entry temperature. However, this procedure is meaningful only in those rare cases where the granulometric characteristics of the clinker in the respective plants to be compared are also similar. 

High temperature DTA is a useful tool for studying the clinkering reactions. Figure 3 shows atypical DTA curve of an industrial raw meal.1 1... 

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