АР15473081 «Development of an integrated technology for the production of road construction materials based on blast-furnace production waste»

Blast furnace slag is a waste produced during pig iron smelting. Part of the liquid blast-furnace slag is subjected to granulation and used for the production of portland slag cement. However, a significant amount of blast-furnace slag (about 300 million tons per year worldwide) accumulates in dumps that require disposal. Dump blast-furnace slag is used for the production of road-building slag crushed stone. Slag crushed stone is much cheaper than natural crushed stone, but differs in heterogeneity in strength, high water absorption (6-8%) and low frost resistance.

The idea of the project is to improve the physical and mechanical characteristics of slag crushed stone by enrichment (sorting) of grains by the strength and impregnating stronger grains (suitable for road building) with a water-repellent composition (hydrophobization).

The integrated use of slag crushed stone in the construction of road bases and slag portland cement for cement-concrete pavements of roads will reduce the cost of road building, reduce the environmental burden due to the disposal of slag dumps and save reserves of natural materials.

1) Kunaev Vyacheslav Alexandrovich – PhD, Director of the Department of Science, Innovation and International Cooperation, Project Leader.

Scopus ID: 57200448577  

ResearcherID: AAR-2188-2020 

https://orcid.org/0000-0001-8283-7186.

2) Bazarov Baurzhan Anuarkhanovich – Doctor of Technical Sciences, Professor, Head of the Department «Construction», scientific consultant.

Scopus ID: 36913827300  

ResearcherID: IVS-8148-2023  

https://orcid.org/0000-0002-8535-5446

Within the framework of the project, studies of the interaction of the physical-mechanical characteristics of aggregate based on the blast furnace slag (bulk density, water absorption, frost resistance) will be carried out, approximation equations of experimental results will be obtained and the correlation of these parameters is will be estimated.

A set of requirements will be established and technical specifications for designing the equipment for hydrophobization and enrichment by strength of road-building aggregate based on the blast furnace slag will be developed.

A technology to improve the physical-mechanical characteristics of the aggregate based on the blast furnace slag by complex processing using methods of hydrophobization and grains enrichment by strength will be developed, a pilot batch of samples of the enriched aggregate based on the blast furnace slag with increased strength and frost resistance will be prepared and the laboratory tests of the samples will be carried out.

2 articles will be published in journals from the first three quartiles with an impact factor in the Web of Science database or having a CiteScore percentile in the Scopus database of at least 50 and 4 articles will be published in peer-reviewed foreign or domestic publications recommended by by Committee for Quality Assurance in the Sphere of Education and Science of MSHE RK.

1 patent for a utility model based on the results of research will be obtained.

Abstracts of the research report obtained on the basis of the research results will be sent to an international conferences.

The research results will be entered into the state register of rights to copyrighted objects.

1) Based on the results of a critical analysis of equipment and promising technologies for the enrichment of non-metallic road-building materials based on industrial waste, a morphological set of mechanization tools and technological processes for sorting road-building aggregate based on industrial waste by grain strength has been established.

2) Experimental samples of the slag aggregate with various bulk densities (from 1086.6 kg/m3 to 1426.9 kg/m3) were prepared. The prepared samples of slag aggregate were tested for water absorption, frost resistance and strength. Mathematical processing of experimental data (using the method of correlation analysis) was performed. This study made it possible to assess the degree of influence of the bulk density of samples of heterogeneous slag aggregate samples on their physical and mechanical characteristics.

3) Approximation equations that relate the physical-mechanical characteristics of aggregate based on the blast furnace slag (water absorption, frost resistance, strength, bulk density)  have been obtained. Based on the obtained approximation equations, a mathematical model describing the relationship of the listed parameters is developed.

4) It is proposed to use a machine for the hydrophobization of slag aggregate for impregnation. The basic requirements for the design of a laboratory use for the hydrophobization of slag aggregate have been established. The main stages have been determined and a technological map of the process of hydrophobization of slag aggregate has been prepared.

5) An experimental assessment of the effect of temperature, the consistency of the water-repellent composition and the time of impregnation of slag aggregate on its water absorption was performed.

6) Mathematical processing of experimental data was performed (using approximation and correlation analysis methods), which made it possible to assess the degree of influence of hydrophobization parameters (impregnation time and temperature of the water-repellent composition) on the water absorption of the material. The results of processing experimental data are presented in the form of a mathematical model of the technological process of hydrophobization of slag rubble.

7) The optimal composition and parameters of the equipment for impregnating slag aggregate with a water-repellent composition have been determined. Based on these data, a technical specification has been developed for the design of a pilot machine for the hydrophobization of aggregate based on metallurgical waste.

8) A 3D model of the experimental machine for the hydrophobization of slag aggregate has been developed in the KOMPAS-3D software environment.

9) Experimental studies have been carried out on the enrichment of slag aggregate by grain density in various ways: by selective crushing and by separation by friction characteristics. Based on the established empirical dependencies, a mathematical model has been developed describing the correlation relationship of the parameters of the technological process of enrichment of aggregate based on blast furnace slag with its physical and mechanical characteristics.

10) The requirements for the parameters of the technological process and equipment (laboratory ball mill) for the enrichment of slag aggregate by selective crushing have been empirically established. Based on these data, a technical specification has been developed for designing of equipment for the enrichment of road-building aggregate based on blast furnace slag  by density (strength).

11) A 3D model of the experimental design of the equipment (friction separator) for the enrichment of slag aggregate by grain density has been developed. An experimental design of a laboratory friction separator was made and tested using a 3D model.

12) A method has been developed and patented to improve the physical and mechanical characteristics of aggregate based on blast furnace slag by complex processing using methods of hydrophobization and grain strength enrichment.

13) A pilot batch of samples of enriched aggregate based on blast furnace slag with increased strength and frost resistance has been prepared.

1) Kunaev V., Bazarov B., Tavshanov I., Kadyrov A., Abdugaliyeva G., Kydyrbayeva S. Evaluation of the effect of enrichment of slag aggregate for pavement subbase by grains density on its physical and mechanical characteristics // Results in Engingeering. – 2023. – 18. – 101181. https://doi.org/10.1016/j.rineng.2023.101181 (Web of Science, Q1, Scopus, 82th percentile);

2) Kunaev V., Tavshanov I., Asanov R. Laboratory evaluation of a complex treatment technology for reducing water absorption of the pavement subbase aggregate from the blast-furnace slag // Engineering Research Express. – 2024. – 6 (1). – 015048. https://doi.org/10.1088/2631-8695/ad1e16 (Web of Science, Q2, Scopus, 53th percentile);

3) Kunaev V., Bazarov B., Kadyrov A., Konakbaeva A. Selective crushing, enrichment by friction properties and hydrophobization for obtaining the sustainable blast furnace slag aggregate for road subbase. – 2024. – 102928. https://doi.org/10.1016/j.asej.2024.102928   (Web of Science, Q1, Scopus, 53th percentile);

4) Кунаев В.А., Тавшанов И.С., Четын А. Анализ оборудования и технологий обогащения щебня из промышленных отходов для строительства объектов транспортной инфраструктуры // Труды университета. – Караганда: КарТУ. – 2023. – № 2. – С. 206-211. URL: http://tu.kstu.kz/publication/publication/download/528 (recomended by CCSHE);

5) Кунаев В.А., Тавшанов И.С., Тимухина Е.Н. Применение фрикционного сепаратора для повышения прочности и снижения водопоглощения дорожно-строительного шлакового щебня // Труды университета. – Караганда: КарТУ. – 2023. – № 3(92). – С. 271-277. URL: http://tu.kstu.kz/publication/publication/download/602 (recomended by CCSHE);

6) Кунаев В.А., Тимухина Е.Н. Проект технологической линии для избирательного дробления и гидрофобизации дорожно-строительного щебня из доменного шлака // Труды университета. – Караганда: КарТУ. – 2023. – № 4(93). – С. 241-246. URL: http://tu.kstu.kz/issue/issue/download/100 (recomended by CCSHE);

7) Кунаев В.А. Патент на полезную модель № 8677 «Способ повышения физико-механических характеристик щебня из доменного шлака». Бюл. № 48 ­от 01.12.2023.URL: https://gosreestr.kazpatent.kz/Utilitymodel/Details?docNumber=382664

8) Кунаев В.А., Кадыров А.С. Современные технологии и материалы из промышленных отходов в дорожном строительстве (Монография). – Темиртау: Карагандинский индустриальный университет, 2024. – 195 с.

9) Кунаев В.А. Лабораторная оценка влияния обогащения шлакового щебня для дорожного строительства по пористости зерен на его физико-механические характеристики. Свидетельство о внесении сведений в государственный реестр прав на объекты, охраняемые авторским правом № 31583 от «5» января 2023 года;

10) Кунаев В.А. Математическая модель технологического процесса гидрофобизации предварительного обогащенного шлакового щебня. Свидетельство о внесении сведений в государственный реестр прав на объекты, охраняемые авторским правом № 40471 от «15» ноября 2023 года;

11) Кунаев В.А. Проект разработки комплексной технологии производства гидрофобизированного обогащенного шлакового щебня: текущие результаты // Сб. трудов межд. научн.-практ. конф. ««Инновационные технологии и инжиниринг», посвященной 60-летию Карагандинского индустриального университета». – Темиртау: КарИУ, 2023. – С. 600-604.

12) Кунаев В.А. Экспериментальная оценка эффективности технологии обработки дорожностроительного шлакового щебня в целях экономии минерального сырья // Сб. трудов межд. научн.-практ. конф. «Ресурсосберегающие технологии в минерально-индустриальном мегакомплексе в условиях устойчивого развития экономики». – Алматы: КазНИТУ, 2024. – C. 144-148.