Utilization of high-inerts lignite fractions in cement raw meal
(EN)
Moutsatsou, A
(EN)
Kakali, G
(EN)
Merkos, P
(EN)
Tsimas, S
(EN)
This paper comprises the study of the partial replacement of Portland cement raw meal by rejected lignite fractions after their treatment by the method of Selective Reduction of Size (SRS). SRS is a process developed in the authors' laboratory for physically upgrading lignites, and leads to two granulometric fractions. The fines are enriched in inorganic material which has a mineralogical and chemical composition very similar to that of cement raw meal. The calorific value of the organic fraction that it contains can also help to meet the energy demand of the burning process. The results are supported by the use of DSC, TG and XRD methods as well as by the determination of the free CaO content. It is concluded that the rejected lignite can replace up to 40 % w/w of the cement raw meal. The burning of the organic material promotes the decomposition of the limestone and the early sintering reactions.
(EN)
