Ключевые слова: micrоsilica

Investigation properties of microsilica to assess the possibility of its use as an additive in concrete production

https://doi.org/10.58224/2618-7183-2025-8-3-5
Аннотация
A comprehensive study of the composition, structure and properties of microsilica from the sludge field of JSC Kremniy was conducted. It was shown that the capture of microsilica during gas purification with a soda solution and its storage under a layer of water on the sludge field for many years contributed to the formation of agglomerates of particles with an average size of 7-16 μm, consisting of nanosized amorphous silica particles of spherical shape. It was found that microsilica has a relatively low pozzolanic activity, and agglomerates of its particles formed during capture during gas purification and long-term storage on the sludge field reduce the efficiency of using microsilica as an active mineral additive. To increase the activity of microsilica and destroy agglomerates, intensive mechanical action is required during the processing of microsilica as part of various building materials. The laboratory studies have confirmed the possibility of using microsilica in the construction industry as an active mineral additive to cements, including as a substitute for part of the clinker, as an "acidic" component of unfired hydraulic and autoclave hardening binder, and as a silica-containing additive to raw sludge for clinker firing. It has been shown that the use of microsilica from JSC "Kremniy" in the construction industry will improve the environmental situation in the region, and the experience of using waste described in the work can be extended to other metallurgical enterprises.
PDF

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
Аннотация
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.
PDF