New horizons of non-ferrous metallurgy in Kazakhstan

The mineral resources of the Earth are finite and many of them are irreplaceable. At the same time, a decrease in ore quality is a global trend and is typical for most metal deposits. Proven reserves of rich ores are almost everywhere running out, and the objective reality is the transition to processing of difficult-to-enrich, complex and poor ore raw materials.

The metallurgical industry in Kazakhstan is the leading sector of the economy, accounting for more than 21% of total industrial production and 43% of total manufacturing industry in 2020.

In terms of the richness of mineral resources and their diversity, the republic is one of the world's leading countries, but in terms of ore quality it is inferior to the main world metal producers.

Solutions to raw materials problems are especially important for non-ferrous metallurgy in Kazakhstan. So, today the copper and lead-zinc sub-sectors are experiencing serious difficulties in providing existing enterprises with raw materials, and ores from Zhezkazgan, Maleevka, and other deposits are running out.

The country's significant potential is the largest porphyry-type copper deposits, the involvement in the development of which is primarily due to the need to solve a number of technological problems, which will allow for the cost-effective processing of such types of low-grade raw materials. Therefore, the creation of highly efficient technologies for the extraction and complex processing of such a class of non-ferrous metal deposits is currently one of the main and urgent tasks of developing existing resources.

The National Center for Integrated Processing of Mineral Raw Materials of the Republic of Kazakhstan, which has extensive experience in successfully solving complex technological problems in the field of ferrous and non-ferrous metallurgy, presented the work "Creation and industrial development of fundamentally new mining and processing technologies that ensure highly effective involvement" for the State Prize of the Republic of Kazakhstan in the field of science and technology named after al-Farabi. the economic turnover of Kazakhstan's hard-to-recover, low-quality and decommissioned polymetallic raw materials reserves".

This work is the result of many years of scientific and technological developments by leading and world-renowned scientific and industrial teams in Kazakhstan, and the authors are prominent scientists of the republic in the field of mining and metallurgical sciences, with extensive experience in the creation and development of new metallurgical technologies.

The technology complexes included in the work correspond to the world level, they are protected by patents of the Republic of Kazakhstan, which make it possible to create a reliable long-term raw material base for non-ferrous and ferrous metallurgy enterprises in Kazakhstan by involving more than 1 billion tons of hard-to-recover, low-quality, decommissioned reserves of copper and oxidized lead-zinc ores in processing.

Only the introduction of technology for the re-processing of stocks written off for losses in various purpose piles at the Tishinsky and Maleevsky mines, Orlovskaya, Artemyevskaya, Pervomaiskaya mines allowed almost 2 times to increase the intensity of ore extraction from chambers, 1.3 times to increase labor productivity and reduce the cost of laying operations, reducing losses and dilution of ore with economic the effect is 1.5 million dollars. The re-mining of ore at the Zhezkazgan deposit made it possible to additionally extract more than 11 million tons of valuable ore from the inter-chamber pillars.

New hydraulic pulse technologies due to the supersonic velocity of the discharged water make it possible to increase the development productivity by almost 15 times. Their use in the destruction of strong and abrasive ores and rocks makes it possible to switch to in-line transportation, ensure the safety of sinking and operation of workings at no additional cost, and reduce the volume of ventilation eightfold.

Herring delivery during underground mining of inclined ore deposits ensures the safe conduct of cleaning operations, significantly reduces the volume of mining preparatory work and operating costs. The internal dump formed in the depleted space with a capacity of 34 million tons allowed Kostanay Minerals JSC to receive savings of 384 million tenge.

When studying the chemistry and mechanism of high-temperature processes, the authors established a previously unknown new phenomenon, namely, a significant acceleration of the formation of iron silicides during the interaction of silicon oxide with carbon and iron in the presence of calcium oxide. The scientific discovery made it possible to propose fundamentally new technological solutions - direct processing of polymetallic oxide ores, bypassing the enrichment stage, with a high degree of extraction of not only heavy non-ferrous metals, but also all other components of the ore and a significant increase in the complexity of the use of raw materials.

This approach has been worked out at the ores of the Zhairem and Shalkia deposits, Shaimerden and Achisai, Aktogay, Sayak, Moldybai, Bozshakol, Nurkazgan, and Shatyrkol deposits. Similarly, it is used on oxidized and mixed copper ores to produce chloride concentrate of copper, rough copper and ferrosilicon.

Of great interest to the ferrous metallurgy industry is an original economical method for producing high-purity and highly concentrated ferrosilicon FS75 with low costs of coke, quartzite, electricity and the complete elimination of scarce steel shavings.

For oxidized and mixed low-grade copper ores from the Aktogay, Kounrad, Benkala, Nurkazgan, Shatyr-kul, Karchiga, Taskora, Borly, Ayak-Kojan, Bozshakol, Baytemir deposits,Beschoku, Zhezkazgan, Babylonskoye, Ai, Koksai, Almaly, Shagala and others have created and mastered new hydrometallurgical processing technologies, which annually produce 12% of Kazakhstan's copper (~50 thousand tons).

The work submitted to the competition allows us to assert that the fundamentally new technological approaches created by the authors contribute to the successful solution of the acute raw material problem in non-ferrous metallurgy and the overall competitiveness of the entire mining and metallurgical industry in Kazakhstan, and the authors of the work deserve to be awarded the al-Farabi State Prize in Science and Technology.

Sultanbek Kozhakhmetov,

Academician of the National Academy of Sciences of the Republic of Kazakhstan,

winner of the USSR State Prize in Science and Technology

Kazakhstanskaya Pravda newspaper, August 12, 2021