Granular Aggregates Based on Finely Dispersed Substandard Raw Materials

It is necessary to solve the ecological problems of regions where there is large-tonnage storage of various finely dispersed materials, including technogenic ones. This article presents the results of an investigation into the possible use of substandard dispersed quartz sands to obtain effective granular aggregates, with the purpose of putting them to use in mortars and concrete. The study used standard and original experimental research methods related to the analysis and preparation of raw materials, technological tests, and the study of the properties of finished composites. Investigations were carried out to obtain composite binders in the component composition of which the use of different ratios of Portland cement and substandard quartz sands prepared in a vortex jet mill was envisaged. It was found that the obtained composite binders had high physical and mechanical characteristics, which was due to the high specific surface area and hydration activity. On the basis of composite binders and finely dispersed quartz sands (fineness from ≤0.16 mm to 1 mm), the granulation of mixtures of 36 types of component compositions was performed. The developed compositions of granular aggregates (GAs) showed the possibility of obtaining them with sufficiently high strength values in cement stone. The studies carried out make it possible to recommend finely dispersed substandard and technogenic materials for the production of GAs, which would ensure the economy of binding materials as well as contribute to the reuse of large-tonnage waste of ferrous and nonferrous metallurgy and the chemical and mining industries.

Innovative Approaches to Using Kazakhstan’s Industrial Ferrous and Nonferrous Tailings in the Production of Ceramic Materials

This paper covers the production of ceramic materials from the tailings of ferrous and nonferrous metallurgy without using convention natural materials. The research addresses the dependency of the polymetallic ore tailings, chromite ore tailings, and physico-mechanical properties of ceramic materials based on the clayey portion of zircon-ilmenite ore gravity tailings. The dependency model is based on the actual experimental data and provides an analytical description of the test results as a function. Regression analysis has produced mathematical models for predicting the properties of ceramic mixtures at points not covered by the experiments. The paper presents five model equations to show:– how the content of chromite-ore tailings and polymetallic-ore tailings affects the compressive strength of ceramic bricks;– how the content of chromite-ore tailings and polymetallic-ore tailings affects the bending strength of ceramic bricks;– how the content of chromite-ore tailings and polymetallic-ore tailings affects the frost resistance of ceramic bricks;– how the content of chromite-ore tailings and polymetallic-ore tailings affects the thermal conductivity of ceramic bricks;– how the content of chromite-ore tailings and polymetallic-ore tailings affects the heat resistance of ceramic bricks;The research team has managed to produce ceramic bricks of high physico-mechanical properties from the tailings of ferrous and nonferrous metallurgy without using convention natural materials.

Use of Nonferrous Metallurgy Waste: Clayey Portion of the Zircon-Ilmenite Ore Gravity Tailings and Pyrite Cinders in Tile-Making

Studies have shown that using nonferrous metallurgy waste in the ceramic mixture for the making of roof tiles improves the final product quality; one can use the clayey portion of the zircon-ilmenite ore gravity tailings as the clay, pyrite cinders as leaners and sintering intensifier, and wollastonite as an agent to reduce shrinkage and prevent deformation-related buckling. The common method of linear regression was used to study the dependency of the basic physico-mechanical properties of tiles on how much clay from the zircon-ilmenite ore gravity tailings, pyrite cinders, and wollastonite is used in manufacture. The resultant mathematical model takes into account the combined effects these components have on the physico-mechanical properties of tiles; it matches well the experimental data.