STUDY OF THE MINERALIZING EFFECT OF CRYOLITE AND ITS INFLUENCE ON THE PROCESSES OF CLINKER FORMATION

The article discusses the effect of the addition of calcium fluoride CaF2 on the dissociation of calcium carbonate CaCO3. When calcium fluoride is added in amounts of 1 and 10% by fluorine ion, a low-temperature liquid phase is formed in the system of calcium carbonate CaCO3, calcium oxide CaO and calcium fluoride CaF2. The temperature of formation of the liquid phase depends on the amount of introduced calcium fluoride CaF2. The presence of a liquid phase leads to a decrease in the rate of decomposition of calcium carbonate, which contributes to the appearance of endothermic effects on the curves of differential scanning calorimetry. With the introduction of 1% fluorine ion, the completion temperature of the decomposition reaction of CaCO3 calcium carbonate is 23 ° C higher than that of non-additive CaCO3. With the introduction of 10% fluorine ion, the completion temperature of the CaCO3 calcium carbonate decomposition reaction is 42 ° C higher than that of non-additive CaCO3. The presence of a low-temperature liquid phase is also confirmed by electron microscopy. After the decomposition of calcium carbonate, the surface of the calcium fluoride particles is enveloped by calcium oxide particles, which is not observed in a mixture of carbonate and calcium fluoride before heat treatment.