White Cement Clinker Roasting Intensification

This article is devoted to the study of the intensifying ability of mineralizers in the production of white cement. Dried raw sludge was used as the initial raw mixture Limited Liability Company «Holcim (Rus) Construction Materials». The reagents CaF₂ and NaF of “pure” qualification were used as mineralizers. The intensifying ability of mineralizers of calcium fluoride and sodium fluoride was studied under conditions of circulation and accumulation of alkali metal salts, depending on the input method. To simulate the circulation and accumulation of alkali metal salts, the reagent Na₂CO₃ of “pure” qualification was introduced into the raw sludge in the amount of 3.5 wt% Na₂O on clinker. Calcium fluoride was introduced in the amount of 1.5 wt% CaF₂, and sodium fluoride in the amount of 1.615 wt% NaF on clinker. Traditional (in the initial mixture) and separate input of mineralizers were used. It has been found that the circulation and accumulation of alkali metal salts lead to a decrease in the whiteness of the clinker. With the traditional input, the efficiency of the mineralizer at 1400 °C is low. The traditional input of mineralizers has practically no effect on the whiteness of the clinker at 1400 °C. Separate input makes it possible to increase the efficiency of the action of mineralizers and achieve a comparable degree of assimilation of free calcium oxide in similar samples even at 1300–1350 °C. Separate input has a positive effect on the whiteness of the clinker. The greatest efficiency was shown by separate injection of calcium fluoride under conditions of circulation and accumulation of alkali metal salts.