The article deals with the perspectives of producing heat-resisting materials on the base of serpentine rocks (a by-product of asbestos production) and the factors preventing it. The section “Materials and methods” describes the methods used in the work and the characteristics of materials. The influence of orthophosphate acid concentration on strength, water resistance and heat resistance of magnesium phosphate cements are estimated. The concentrations of the acid providing the maximum limits of bending and compression strength are identified herein. The resistance of elaborated material to the influence of high temperatures and its water resistance are estimated herein. The phase composition of the developed material is defined and the article proves that there is no harmful gas emission at heating in the studied compositions. We showed the benefits of the scientific direction and research in this area

Water treatment plant (WTP) sludge is actively used in building materials production. The object of this research was modifying additives for ceramic bricks from WTP aluminium-containing sludge. The research aim of this study was to determine the suitability of a million-plus population city’s WTP sludge as a burning-out additive in the production of structural ceramics and to establish the optimal conditions for obtaining products with the best characteristics. The raw water belongs to water belongs to the hydrocarbonate class, the calcium group, and it is of low turbidity (1.5–40 mg/L kaolin). Sludge, sourced from WTP sedimentation tanks, was dewatered by adding lime or by using the freezing-thawing method. The spray-dried WTP sludge is introduced into the clay in amounts of 5% to 20% by weight. The addition of 20% reduces the sensitivity of the clay to drying, reduces the density of ceramic by 20% and simultaneously increases its compressive strength from 7.0 to 10.2 MPa. The use of WTP sludge as a modifying additive, pretreated by the freezing-thawing method, makes it possible to obtain ceramic bricks with improved properties. The results can be used for WTP sludge containing aluminium obtained by treating water of medium turbidity and medium colour.

According to the study results, the influence of complex additives based on microsilica and superplasticizers on the processes of the heat release, hydration, hardening, formation of the structure and properties of cement stone was determined. Calorimetry, derivatography, X-ray phase analysis, electronic microscopy and physical-mechanical methods for analyzing the properties of cement stone were used for the studies. It was established that plasticizing additives, in addition to the main water-reducing and rheological functions, regulate cement solidification and hardening while polycarboxylate superplasticizers even contribute to the formation of a special, amorphized microstructure of cement stone. In a complex containing microsilica and a polycarboxylate superplasticizer the strength increases sharply with a sharp drop in the capillary porosity responsible for the density, permeability, durability, and hence, the longevity of concrete. All this is a weighty argument in favor of the use of microsilica jointly with a polycarboxylate superplasticizer in road concretes operated under aggressive conditions.

The article considers the problem of reducing the energy consumption during the production process of magnesia cement based on brucite admixed with serpentine, because this solid requires roasting at high temperatures (1100–1200°C). It was demonstrated that the most effective way to increase the energy efficiency of the technology is to use additives, so that roasting intensifiers. We investigated the effect of various additives and intensifiers to reduce the roasting temperature of serpentinized brucite material. We found that the most effective additives are those, destabilizing a crystal lattice of roasted solid and simultaneously producing the hot melt during their dehydration. It was shown that the highest temperature can be reduced by 100–300°C without increasing the heat treatment time. We also estimated the quality of magnesia cement obtained by the developed method and confirmed its compliance with all relevant regulations