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Gypsum composites are promising building materials, but they have disadvantages such as low strength and water resistance. To improve these properties, a self-reinforcement method can be used, where the gypsum matrix is reinforced with crystals other than gypsum. One type of such crystals is ettringite. To obtain a self-reinforced gypsum composite, it is necessary to maintain a high pH environment and sufficient ions to form ettringite. In this work high-calcium fly ash, which is a waste product of coal combustion...

Construction technologies are among the most critical in terms of negative impact on the environment. Burnt binders, primarily cement and air-lime, emit significant volumes of carbon dioxide and man-made heat. At the same time, a large amount of hydrocarbon fuel is also consumed for their firing. Therefore, to achieve sustainable development goals, the development of alternative binder formulations or innovative ways to produce traditional binders with low carbon emissions is necessary. The synthesis of low-carbon...

India generates over 500 million tonnes of agricultural waste annually, much of which is lignocellulosic biomass rich in silica, calcium, potassium, and carbon elements, which are favourable for catalytic applications. This study highlights the valorisation of abundant agro-wastes such as rice husk (up to 20% silica), coconut shell (74%-78% fixed carbon), sugarcane bagasse (45%-55% cellulose), and tamarind seed (rich in polysaccharides and carbon), as cost-effective and sustainable catalysts. Various preparation t...

One of the promising areas of utilization of solid technogenic waste from energy generation is their processing to produce alumina, the production of which is accompanied by the formation of by-products that can be used to produce belite sludge (2CaO-SiO2). The basic schemes of purification of the initial ash from carbon and iron oxides are proposed. Using the example of ash from coal burning in the Ekibastuz basin, the possibility of obtaining two grades of belite sludge is shown. Up to 1.5-1.8 tons of belite slu...

Ash and slag waste (ASW) is a finely dispersed mineral material resulting from the combustion of brown and hard coal at thermal power plants. The involvement of ash and slag waste in industrial circulation is one of the effective ways to solve the issue of energy and resource saving. Utilization of ash and slag waste in industrial production will provide a solution to the environmental problem of environmental pollution by industrial waste - technogenic fine dust and harmful effluents by gradually reducing the rat...

Gypsum-based materials and products currently deserve special attention from specialists in many industries. They are distinguished by high environmental friendliness, manufacturability and safety. The construction industry is showing additional interest in their increased comfort, reduced sound insulation and thermal insulation. Obtaining crystallization structures directly from gypsum dihydrate using a non-hydration hardening scheme competes with many modern technological approaches. In the production of non-fir...

Among the existing methods of processing waste from coal-fired thermal power plants, little attention is paid to the problem of ash disposal with variable composition. During the combustion of coals, various chemical reactions occur as part of their mineral part, resulting in the formation of a new technogenic raw material that differs from natural raw materials in chemical and phase composition and has other technological properties. Using the example of a coal-fired power plant burning coals from six different d...

Improving the performance of the gypsum binder is possible by strengthening the gypsum matrix. The increase in strength is ensured by the introduction of a complex of mineral and chemical additives. The use of waste as components of such a complex solves a set of problems. The market is saturated with competitive and high-quality materials. Designed materials meet modern requirements. In addition, the problems of waste disposal, freeing up space, environmental protection and reducing the resource intensity of prod...

The work is devoted to the study of fuel ash as components of composite cements and building mixtures based on them. The use of bottom ash as raw material is an urgent problem. On the one hand, their use in production solves the issue of creating resource and energy saving technologies and increasing the efficiency of cements and concretes. The use of ash makes it possible to improve the properties of cements, bricks, products from aerated and heavy concrete, light aggregates, and the quality of road construction....

As a result of the operation of thermal power plants used solid hydrocarbon fuel, ash and slag waste (ASW) is formed. ASW is a finely dispersed mineral material remaining as a result of burning brown and hard coal. The involvement of ASW in industrial turnover is one of the most effective ways to solve the issue of energy and resource conservation. The share of involvement of these types of waste in economic turnover in the European Union is about 98%, in China about 80%, and in Russia this indicator does not exce...

Solutions to the environmental problems associated with the burning of coal in power plants are in poor condition. One of the main problems is the continuous growth and accumulation of ash and slag waste (ASW). Ash and slag waste is a major source of raw materials for various industries. However, the degree of use of ash and slag waste at Russian thermal power plants does not exceed 2 million tons / year, with an annual output of 25-28 million tons. Modern methods of enrichment and processing allow the use of ash ...

In the article synthesis of structures of disperse systems on the basis of gypsum is considered. Such systems are necessary for receiving materials which exclude burning of raw materials on the basis of gypsum waste for the receiving binders. For them use a certain composition of raw mix. Selection of structure of compositions allows to increase properties of materials. Such materials are characterized by high strength. The process of formation of structure of a gypsum which is received by hyper pressing is studie...