EXPERIENCES ON KAOLINITIC CLAYS ACTIVATION AT PILOT SCALE: ISLA, MOA, YAGUAJAY AND REMEDIOS AS CASE STUDIES

Abstract

Introduction:
The industrial processes of thermal activation of kaolinitic clays represent an alternative approach in the implementation-expansion phase to reduce global CO2 emissions.
Objective:
To present experiences, and some of the most relevant results obtained during calcination tests of kaolinitic clays from different deposits in Cuba, in the existing experimental pilot plant at Universidad Central “Marta Abreu” de Las Villas.
Materials and Methods:
The main physical and chemical characteristics of the clays under study, determined using XRF and XRD techniques, are described, and the stages of the technological process for activating these materials in the experimental facility are analyzed. The changes that occur in the particle size distribution are compared by sieving.
Results and Discussion:
The degree of dehydroxylation, and the pozzolanic reactivity of the material subjected to thermal modification are correlated with its chemical and mineralogical composition; and the results of the compressive strength achieved in standardized mortars for different formulations of activated kaolinitic clays are evaluated, both in the laboratory and at pilot scale.
Conclusions:
It is demonstrated that the initial preparation of raw materials through fine grinding, and the strict control of oven temperature and rotation, are essential parameters for achieving satisfactory dehydroxylation indicators. All national kaolinitic clays activated at pilot scale meet the necessary quality parameters and requirements for their use as supplementary cementitious materials.