EFFECT OF CLAY CALCINATION TEMPERATURE ON POZZOLANIC ACTIVITY

Cement production undergoes four main stages: raw material grinding, blending, rotary kiln firing, and final grinding. Throughout these processes, energy is utilized, and detrimental gases are discharged. Mitigating CO2 emissions from cement manufacturing can be accomplished via techniques like enhancing production technologies and substituting cement in concrete blends with pozzolanic substances. Research endeavors are underway to formulate substitute binding agents for cement, aiming to diminish energy requirements and greenhouse gas discharges in cement fabrication. Emission reduction methods such as partial or high volume replacement of cement with natural and artificial pozzolans such as slag, fly ash, calcined clay are among the most frequently studied topics on a global scale. Even if the advantages of using mineral additives in cementitious systems have been proven in the literature, there are several reasons that limit their industrial use. Recently, studies on various clay minerals, which can have high pozzolanic activity by calcining at 600-900 o C, have been intensified. This study focuses on the effect of clay calcination temperature on pozzolanic activation. For this purpose, raw clay obtained from nature was calcined at 600, 700, 800 and 900 o C. In addition, natural pozzolan was also used to compare the calcined clay performance. Natural pozzolan and calcined clays were tested for pozzolanic activity according to TS-25. As a result, calcined clay performed better than natural pozzolan at all temperature values. Moreover, it was found that calcining at 800 o C was the most suitable condition for the maximum performance of the clay used.