Evaporation of volatiles polymorphic transitions reducing conditions

5 Evaporation of volatiles polymorphic transitions reducing conditions 

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 

For normal cements, the effects of reducing conditions are all undesirable, but for white cements, which contain very little iron, reducing conditions are preferred because they yield a whiter product. Locher (LI2) concluded that the bad effects of reducing conditions were avoided so long as the clinker left the kiln at a temperature of at least 1250 C and thereafter cooled rapidly in air however, reoxidation of Fe in alite below 1300°C has been observed to cause the formation of exsolution lamellae consisting of CjF and belite (Lll). 

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