Kolesnikova O.G.

Master of Engineering and Technology, M. Auezov South Kazakhstan University

Research on air purification from pulverized large-tonnage tailings of non-ferrous metal ores and the possibility of their use as secondary raw materials

https://doi.org/10.58224/2618-7183-2025-8-6-1
Аннотация
Pulverized waste (large-tonnage tailings) from the enrichment of non-ferrous metal ores pose a significant environmental threat and a health hazard to the personnel of enterprises and the population of nearby territories. In this regard, this study is devoted to solving the problem of dust suppression with the prospect of subsequent complex tailings processing. The effectiveness of a combined method combining fine-dispersed hydraulic spraying and pulsating ventilation for dust deposition from the tailings of the former Kentau Enrichment Plant (Kentau, Kazakhstan) has been experimentally studied. Laboratory tests were carried out on a specialized stand with monitoring of microclimatic parameters. The results showed that the combined method reduces the dust deposition time by approximately 30% compared to traditional irrigation and by more than two times compared to natural precipitation. Optimal process parameters have been established: nozzle diameter of 10 microns, liquid pressure of 5.4 MPa, air flow velocity of 4 m/s, pulsation frequency of 13 Hz. Based on the X-ray phase analysis of the tailings composition (the total content of zinc compounds is ~3.77%, lead ~4.47%), the economic feasibility of their complex processing is substantiated. A two-stage technology is proposed: preliminary, associated extraction of valuable metals (Zn and Pb) followed by the use of a non-metallized residue rich in oxides of silicon, aluminum and calcium in the production of building materials (cement clinker, ceramics). Thus, effective dust suppression is the first step towards the transition from passive waste storage to active recycling within the framework of the principles of circular economy, which will significantly improve the environmental situation in the region.
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Development of a modified bitumen emulsion to enhance the operational properties of asphalt concrete

https://doi.org/10.58224/2618-7183-2025-8-3-1
Аннотация
At present, the primary objective of the road construction industry is to increase the service life of road pavements by implementing innovative technologies that meet modern standards of operational reliability. The key advantages of bitumen emulsions were analyzed, including improved adhesion and cohesion, environmental safety, resistance to water exposure, rapid curing and opening to traffic, applicability under cold conditions, as well as enhanced stability and durability. The research findings confirm the benefits of using bitumen emulsions in road construction, contributing to high-quality and long-lasting pavement performance. Studies were conducted on the modification of petroleum bitumen. The additional incorporation of Kulantau vermiculite into the composition enhances and stabilizes adhesion across a wide range of ambient humidity and temperature conditions. The adhesion process can be regarded as the adsorption of bitumen emulsion on the surface of mineral aggregates. Adsorption occurs through intermolecular interactions, and adhesion is improved by strengthening these interactions, which is achieved by increasing the activity of the bitumen emulsion through the introduction of additives with active functional groups. It was found that incorporating secondary polyethylene and Kulantau vermiculite into asphalt concrete leads to a noticeable decrease in the air void content. This reduction enhances the material’s resistance to moisture and freeze-thaw cycles.
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