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An increase in the activity of the cement of Plant 1 was made by changing the granulometric composition of its sludge. The change in the granulometric composition of the sludge of Plant 1 was made due to the coarsening of the grinding, by inserting limestone with a fraction of 0.315–0.2 mm in the amount of 3 and 6% wt. and due to the re-grinding of the sludge during the 0, 5, 10, 30, 60, 90 min in a 1-L mill with a standard range of grinding environment at a humidity of 37%. It was found that with an increase in the fineness of the sludge grinding, a more complete absorption of calcium oxide is observed. The binding rate of free calcium oxide increases slightly up to a mixture with 10 min of re-grinding. Then, at 30 min of re-grinding, the binding rate of calcium oxide increases dramatically. In the clinker from the ground sludge, an increase in the proportion of synthesized alite is observed.

The color control of Portland cement clinker was regulated by separate insertion of calcium fluoride in the presence of Na2O. Studies were carried out on a raw mixture of pure reagents with a Fe2O3 content equal to 2.93%. The mixture has the following characteristics: KH = 0.93; AM = 1.24; SM = 2.18. Calcium fluoride was inserted as a CaF2 reagent of the “pure” qualification. Na2O was inserted as a “pure” Na2CO3 reagent. The samples were roasted in a laboratory furnace at 1300 °C with an isothermal exposure time of 20 min. The heating speed of the furnace is 10 °C/min. The color change was determined by measuring the brightness coefficient on a reference polished barium sulfate plate using an FB-2 gloss meter. The content of free calcium oxide was determined by the ethyl-glycerate method. It was found that the optimal approach for increasing the clinker whiteness is to insert 1.5% CaF2 separately in the presence of 3.5% Na2O. The amount of 3.5% Na2O is sufficient to bind stoichiometric all aluminum in Na2O∙Al2O3. The binding of Al2O3 to sodium aluminate prevents the formation of calcium aluminoferrites. At the same time, the whiteness of the compound with a mineralizer is 49.5%. In the compound without a mineralizer, it reaches 39%. An increase in the clinker whiteness to the maximum is accompanied by a decrease in the content of free calcium oxide. In the compound without a mineralizer, it is 20.1%. The compound with a mineralizer has a free calcium oxide content of 5.28%.

This article is devoted to studies to establish the effect of separate input of the mineralizer on the properties of white cement clinker. In the course of the research, the 2C2S·CaF2 mineralizer was separately introduced into the raw material mixture for the production of white cement, prepared from the chalk of the Belgorodsky cement deposit and the kaolin of the Zhuravlinny log deposit. It was found that the separate input of the 2C2S·CaF2 mineralizer increases the whiteness of white cement clinker by 10–16% abs. and contributes to clinker with a shade closer to white than without a mineralizer. The separate input of the 2C2S∙CaF2 mineralizer allows achieving almost complete assimilation of calcium oxide even at a temperature of 1300 °C. The phase composition of the samples obtained by separate input of the 2C2S∙CaF2 mineralizer is identical to the samples without a mineralizer, except for the C12A7. Separate input of the mineralizer does not adversely affect the compressive strength of white cement samples. The phase composition of the hydration products does not differ from the phase composition of the control samples without the mineralizer.