Blast furnace slags are subdivided into granular and dump. Granulated slag is widely used in the construction industry to production of Portland cement, Portland slag cement, slagalkaline cements, and concretes based on these cements. Dump slag is of less use, because it has low activity. The phase composition of granular and waste slag was investigated by methods of physicochemical analysis. The slags contain minerals that are present in Portland cement clinker. Concrete samples were made using granular, waste slag and sand. Unsatisfactory results in compressive and flexural strength were shown by a sample made of only two types of slag. The best strength results were obtained for a composition in which there are three components: granular slag, dump slag (filler) and sodium hydroxide. Electronic images have confirmed the appearance of low-basic calcium silicates, which provide the strength of the cementless composite. The resulting concrete composition is resource-saving, because made from production waste. And it can be called energy-saving, because no energy is expended to obtain components. The ecological feasibility of the production of such concrete is due to the absence of emissions of pollutants into the atmosphere (including carbon dioxide), since the firing of cement clinker is not needed.

In recent years, solid waste of the production of mineral fertilizers, phosphogypsum, has been of great scientific and practical interest in construction. The results of scientific research and practical experience in many countries have convincingly proved the technical feasibility and feasibility of using phosphogypsum. The problems of reducing impurities of phosphorus and fluorine in the manufacture of building materials from phosphogypsum are considered. Comparative experimental studies of the presence of phosphorus impurities for the initial phosphogypsum of the Dnieper Mineral Fertilizer Plant, calcined phosphogypsum and mixtures of phosphogypsum were carried out. Comparative indicators of the presence of radioactive elements in phosphogypsum are given. It is shown that there are methods for reducing heavy metals in phosphogypsum.

Theoretical calculation of the thermal effect of formation of minerals of binders is carried out. The dependence allowing calculating the thermal effect of formation of minerals of lime, gypsum, slag cement, portland cement, dolomite cement is presented. The formula also takes into account the effect of organic components in the mixture. A comparative analysis of the energy efficiency of different types of binder in concrete is carried out. It is shown that the use of slag cement in the production of concrete mix is twice as effective as portland cement. This is due to the presence in the slag of calcium oxide, which does not need energy to carry out the endothermic decarbonization reaction. Lime in the concrete composition has a rate of energy consumption is five times greater. This means, industrial waste which contains calcium oxide (slag, ash and others) can replace natural materials with high efficiency.

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