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Keywords: microsilica

Investigation properties of waste from the chemical and metallurgical industries to assess the possibility of their use in concrete production

https://doi.org/10.58224/2618-7183-2025-8-4-7
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Abstract
The investigation was conducted on waste from the chemical industry in the form of carbide silt and metallurgical industry in the form of microsilica. For the study, X-ray phase analysis used on a Shimadzu XRD-7000 diffractometer in Cu Kα radiation. Electron microscopic studies were carried out according to GOST R ISO 22309-2015 on a Tescan Vega III SBH electron microscope with an integrated Oxford X-Act energy-dispersive microanalysis system. The Co standard (MAC, reg. no. 9941 Co) and a cassette of standard samples (MAC, reg. no. 11192) were used as samples. Samples were prepared at the Quorum Q150RES spraying station. The amount of raw sludge components was calculated taking into account the preservation of the saturation coefficient and modular characteristics of the cement plant. The calculation of the raw mix consisted in determining the ratios between its components based on the chemical composition of the raw materials and the specified characteristics of the clinker. The possibility is shown and the limits of carbide silt input are determined for use as a lime component of raw sludge in obtaining cement clinker. The possibility of adjusting the lime component of raw sludge by using microsilica is established, which will allow maintaining a balance in silicon content. The identity in the formation of the main clinker phases formed during sludge firing for the pilot sample and the sample made from the enterprise sludge is proven by the X-ray method. Cement of the CEM-II/A22.5N brand was obtained in laboratory conditions, the properties of which correspond to the properties of cement of the industrial enterprise. It is shown that the use of carbide silt and microsilica in the cement industry will allow not only to use them as raw materials, but also to improve the environmental situation in the territory adjacent to these enterprises.
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DEVELOPMENT OF SPECIAL RECIPES OF BINDING COMPOSITIONS WITH IMPROVED PROPERTIES

https://doi.org/10.34031/2618-7183-2020-3-4-5-12
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 5-12 p.
Abstract
Abstract: the ecological safety of earthly civilization suffers from the accumulation of huge volumes of industrial waste, the natural resource potential is decreasing, therefore, special attention is paid to the development of less costly and low energy-intensive technologies for obtaining new building materials, the implementation of which does not require high-temperature and expensive technological processing, and will allow the use of secondary and substandard raw materials.
The work presents the results of the development of special formulations of binder compositions of alkaline activation based on cement production wastes in the form of aspiration and clinker dust from electrostatic precipitators of rotary kilns and waste from the metallurgical industry - ferrosilicon additives in the form of active silica, which will allow obtaining new building materials with improved properties.
The paper investigates the properties of an alkaline cement paste and cement stone, reveals issues related to the theoretical foundations of the formation of the structure and strength of an artificial stone based on an alkaline activator. The research results, in our opinion, are certainly of practical importance for the construction industry, as the proposed formulations of clinker-free cements can partially replace expensive and energy-intensive Portland cement, making it possible to create strong and durable concrete and reinforced concrete structures.
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FIBER CONCRETE FOR 3-D ADDITIVE TECHNOLOGIES

https://doi.org/10.34031/2618-7183-2019-2-4-14-20
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 14-20 p.
Abstract
Fine-grained fiber concrete used in 3D printing is significantly different from conventional heavy concrete, which is determined by the increased consumption of cement, low water-cement ratio and the absence of large aggregates. The largest grain size of fine aggregate is selected taking into account the thickness of the section, the frequency and type of reinforcement, as well as the method of concrete placement. Despite the fact that the tensile strength of concrete on fine sand is more than 1.5 times higher than the strength of concrete on coarse sand, while there is a decrease in compressive strength. Due to the peculiarities of the technology of concrete manufacturing for layering, the use of coarse sands is impractical, and therefore it was decided to use quartz sand with a particle size module of 1.12 as a filler.
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