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На основе алюмосиликатного сырья Республики Казахстан предложена технология получения сверхплотных алюмосиликатных огнеупоров с повышенной шлакоустойчивостью для тепловых процессов утилизации фторсодержащих углеродистых отходов. Использование «керамической» технологии позволяет получать структуру с водопоглощением менее 1 % как у шамота, так и у огнеупорных изделий с разным содержанием Al2O3.

Improving wear resistance of elements of mining and processing equipment, subjected to abrasion and shock loads, is an actual task, since it determines effectiveness of mining operations to a great extent. Results of industrial tests of two kinds of mining and processing equipment details, manufactured of pilot wear-resistant alloys, presented. Two sidepieces plates for jaw crushers were manufactured of steel based on 30Х3МФ grade and additionally alloyed by niobium (up to 0.15%) as a strong carbide-forming element. As a comparing sample, steel 30Х3МФ without additional alloying was used. The second kind of details to test – sprockets, used as grinding bodies in the crushers for medium ore crushing. The sprockets were casted of chromic iron with increased nickel content (up to 3.5%) to increase the shock ductility, vanadium and titanium content (together up to 1.5%) – to form carbides of MeC type at decreased chrome content (down to 16%). As the comparing sample sprockets ware used, casted of ИХЧ28 grade iron, which is used for these purposes at present. The tests were accomplished at the operating equipment during medium crushing and grinding of “Bogach” deposit ore. The test cycles corresponded to the accepted at the plants crushing cycles – 18 h. The tests were duplicated 2 times. After tests completion the percent of wear of pilot samples was evaluated. The wear was evaluated by relative mass change. The results obtained showed, that the pilot samples have higher wear resistance approximately by 30%.

Samples of aluminosilicate refractory after operation in the shaft and in the hearth of a coke-gas cupola were investigated; this cupola was used for smelting of cast iron with spheroidal graphite using carbon wastes from aluminium electrolysis production as a reducing agent. Use of only fluorine-containing carbon wastes as a solid fuel in cast iron production allows to utilize hazardous man-caused wastes, improves the economic performance of production and has influence on resistance of fireclay refractories. It was established that the products acquire a distinct zone features during the service, due to penetration of the components of gas and liquid phases and the effect of low-boiling components of carbon-containing wastes. Upon that, changes in the structure along the distance from the working space are complex ones in lining thickness and in concentration of volatile components in the “cold” parts of the lining. Permanent character of the mullite content in different zones of fireclay products can be traced, as well as a slight increase in the less altered zone, despite the different service conditions. Absence of alkaline and fluoride phases in the zones of refractory products in the pores and structure of the fireclay refractory was established, due to migration of these gaseous phases into the working space of the cupola with their subsequent removal with furnace gases. Additional development of mullite in certain zones of refractory was revealed, resulting by its synthesis from alumina that did not react during fireclay refractories manufacture under the mineralizing action of a fluorine compound. Use of fluorine-containing carbonaceous wastes as a solid fuel in cast iron production makes it possible to utilize hazardous man-caused wastes, improves the economic performance of production and has slight effect on resistance of aluminosilicate refractories in the conditions of a coke-gas cupola. © SIDORINA E. A., ISAGULOV A. Z., KASHCHEEV I. D., ZEMLYANOY K. G., 2022.

Nonmetallic inclusions in steel such as oxides, silicates, aluminates, spinels, etc. substantially reduce the quality of metal. They are mainly introduced by the slag formed on the metal surface of a doublestrand plant. It is proposed to separate the slag from the metal using a special perforated tube installed on the refractory pocket block of the ladle bottom and fixed with gunning mix. The use of this device for continuous slab casting ensures the high quality of hot- and cold-rolled sheets.

Based on studies, the technological process results of the production of a complex calcium-containing ferrous alloy of waste blast-furnace slag using high-ash coal from the Saryadyr coal field and coal slurry from the Karaganda coal basin are presented. The study was conducted on the experimental site of the Abishev Chemical Metallurgical Institute using an ore-smelting furnace equipped with a 200-kV A transformer. The main task of the study was ensuring the complete reduction of all oxides of the charge comprised of blast-furnace slag, high-ash coal, and coal slurry in a continuous, stable, and easy-to-control slagless process.

The influence of the structure of refractory products on such operational properties as slag resistance and heat resistance is considered. As samples, a conventional chamotte refractory (standard) and chamotte refractory made according to a new technology using non-stationary pressing pressure were used. It is shown that the porosity, slag resistance and heat resistance of products manufactured using unsteady pressure is higher than that of the standard.Ill.4. Ref. 4. Tab. 2.

This work presents the results of smelting ferromanganese from high-silica iron-manganese ores with 36 % manganese content by the flux method. The Shubarkol deposit coal and metallurgical coke as reducing agents were used. The fluxing material was solid slag from the smelting of medium-carbon ferromanganese. The technological modes of the smelting process are established. The optimal composition of the charge was determined. As a result of the theoretical and experimental studies, the tasks have been solved completely - the smelting technology of high-silicon ferromanganese was developed and tested using a substandard raw materials, such as iron-manganese ores and flux.

Scientists of the Chemical-Metallurgical Institute named after Zh. Abishev develop new types of highly effective alloys based on resource-saving technologies that allow the complex processing of natural and technogenic raw materials, such as carbonaceous waste, chrome ore fines, etc. Therefore, it has led to the creation of a onestage, slag-free and non-waste technology with the maximum use of all useful charge components. With disappearance of rich ore reserves, as well as the expansion of demand for raw materials and the development of technology, the rich ores are replaced by poorer and substandard ones that require new methods of processing. The maximum use of raw materials and industrial waste, if this is economically justified, is one of the basic requirements for the technology. This task is closely intertwined, and in many cases coincides with another task – the development of integrated methods of raw materials processing, which, in the general production cycle, allows using, if possible, all useful elements of raw materials. The main objective of the study is to find ways to improve the use of sub-standard chrome ore. As a reducing agent in the electrothermal smelting of the ACS alloy, instead of expensive coke, without which no process of carbothermic smelting is required, a cheap high-ash Borly coal was used. The coal ash, which mainly consists of silica and alumina, is an additional source of silicon and aluminum in the alloy. This technology will be simple and allows regarding substandard chromium ore as a complex metallurgical raw material, since not only chrome is used, but also the components of the waste rock – silicon and aluminum. As a result of the complete reduction of all charge oxides, this technology will make it possible to obtain a complex alloy of ACS with an approximate chemical composition: 39 – 43 % of chromium, 23 – 27 % of silicon, 7 – 10 % of aluminum. The transition of the main components of the charge to the alloy will be: 82 – 85 % of chromium, 68 – 70 % of silicon, 59 – 60 % of aluminum. In this paper, the results of experimental studies on the production of a complex alloy of ACS (aluminum-chromium-silicon) from high-ash coals of the Borly deposit and chrome ore minerals of the Donskoi GOK are presented. The course of furnace operation is described with a lack, excess, and also the calculated amount of the reducing agent. The ways of eliminating the upset in furnace operation are shown.

At Abishev Chemical and Metallurgical Institute, highly effective new alloys have been developed on the basis of resource-saving technology. The alloys may be produced from natural and industrial materials such as coal waste and chromium-ore fines. The result is a single-stage, slag-free, and waste-free technology with the maximum utilization of all the useful batch components. As reserves of rich ores are exhausted, alternatives must be sought. The use of leaner and unconditioned ores calls for new processing methods. Such technologies must make the best possible use of the raw materials and production wastes, within the limits of economic feasibility. In many cases, this complex problem is associated with the development of complex processing methods capable of utilizing all the useful components in the raw materials within a single production cycle. In the present work, the goal is to find means of more efficiently utilizing unconditioned chromium ore. In the electrosmelting of aluminum–chromium–silicon alloy, the traditional reducing agent is coke, which is expensive. Our proposal is to use inexpensive high-ash Borly coal. The ash in this coal consists mainly of silica and aluminum and provides an additional source of silicon and aluminum for the alloy. The proposed technology is simple and makes effective use of unconditioned chromium ore, which provides not only chromium but also the silicon and aluminum present in the ash. By complete reduction of all the oxides in the batch, this technology yields aluminum–chromium–silicon alloy with the following approximate composition: 39–43% Cr, 23–27% Si, and 7–10% Al. The extraction of the basic batch components in the alloy is as follows: 82–85% Cr, 68–70% Si, and 59–60% Al. Experimental data are presented for the production of aluminum–chromium–silicon alloy from high-ash Borly coal and chromium-ore fines from Don enrichment facility. Furnace operation is described in the case of deficient, excess, and correct quantities of reducing agent. Methods of eliminating furnace disruption are outlined.

The effect of refractory product structure on such operational properties as slag resistance and thermal shock resistance is considered. The specimens used are conventional chamotte refractory (standard) and chamotte refractory prepared by new technology using variable pressing pressure. It is shown that porosity, slag resistance, and thermal shock resistance of products manufactured using variable pressure are better than those of the standard.