Azerbaijan is one of the oldest oil and gas provinces, where more than 2 bln tons of oil have been extracted over more than a century. At present, the oil production is declining and mainly determined by production from the Azeri-Chirag-Guneshli offshore block (AChG). Compared to oil, the opportunities for further growing natural gas reserves and production are very promising. For the latest years, a number of large gas condensate fields have been discovered in the deep-water part of South Caspian Sea, such as Shakh-Deniz, Apsheron, Umid. There are a number of prospects that have not yet been drilled in this part of the sea basin. The paper assesses their prospectivity, substantiates the priority exploration targets and, on the basis of the statistical analysis of the quantitative gas/oil ratio data for many other Azerbaijanian and world basins, an attempt is made to assess the reserves in the prospects. The total recoverable oil reserves in Azerbaijan are estimated at 3.5 bln tons, of which slightly above 2 bln tons have already been extracted. Based on the statistically estimated ratio between the volumes of gas and oil in various basins of the world, including Azerbaijan, the total possible natural gas reserves in Azerbaijan are estimated at about 4 trillion m3 . This is in agreement with the other available estimates. Of this volume of natural gas, 0.85 trillion m3 has already been extracted, and the approved geological reserves are estimated at 2.55 trillion m3 . Almost 83% of the extracted natural gas belonged to offshore fields. This trend will continue in the future, and, moreover, will be strengthened due to large volumes of gas condensate accumulations in the deepwater part of the basin. In this part of the basin, the most attractive prospects are Mashal, Shafag, and Israfil Huseynov, total reserves of which are expected at 0.6 trillion m3 of natural gas.

Copper and scheelite concentrates are produced from scheelite-sulfide ores of the Vostok-2 deposit at the Primorsky processing plant. Chalcopyrite, gold, silver, and harmful impurities (arsenopyrite, pyrrhotite) are extracted into the copper concentrate. As a collector, dialkyldithiophosphate-type IMA-I413p reagent is used. Bulk sulfide concentrate is produced using activated carbon and trisodium phosphate; copper cleaner flotation is carried out in the medium of ferrous sulfate. The commercial copper concentrate contains 16 % copper, 33 g/t gold, and 280 g/t silver. The recovery of the metals is 67.6, 44.7, and 50.1 %, respectively. The weight fraction of arsenic in the ore fluctuates in the range of 0.04–0.25%, and that in the concentrate, 0.7–2.3 %. The enterprise looks for ways to increase recovery of the valuable metals and decrease content of arsenic in the copper concentrate to below 1% at the expense of increasing contrast in the separation of chalcopyrite from iron sulfides/arsenopyrite/pyrrhotite. For solving this problem, we performed a study of flotation properties of sulfide collectors based on dialkyldithiophosphates: BTF-15221, BTF -271, non-ionic collector Reaflot-277, and combinations of Reaflot-277 and IMA-I413p. Applying BTF-15221 collector allowed, as compared to the standard IMA-I413p reagent, to increase recovery of copper, gold, and silver and reduce arsenic content in the copper concentrate. The higher selectivity of BTF-15221 as compared to IMA-I413p was confirmed by the fact that the bulk of the increase in copper recovery and decrease in the weight fraction of arsenic in the copper concentrate was achieved in the selective cycle. Besides, during the study, surface activity and hydrophobizing ability of the water-soluble collectors were assessed. Using the example of BTF-15221, it was shown that improvement of the reagent collecting properties can be achieved not only due to increasing the surface activity of the reagent, but also at its decrease – in case of sufficient hydrophobizing ability of the reagent, close to that of the standard reagent. By adjusting these parameters through the use of low-molecular weight homologues of the main components, it is feasible to increase or decrease the selectivity and collecting ability of the reagent. Collector BTF-15221 is of practical interest for further testing in flotation of copper-arsenic and other ore types.

Mineral resource base of the Republic of Kazakhstan, being as the basis of its economy, plays a special role not only in sustainable development of the country, but also in the formation of successful international relations. The paper substantiates the direction of the mining and metallurgical complex development in the Republic of Kazakhstan towards solving the problem of increasing the country's long-term competitiveness. It was demonstrated that achieving these goals will allow building the potential for consistent and secure participation of the national economy in market interaction with leading global partners on mutually beneficial terms. At the same time, despite forecasted promising geological data, significant excess of the scope of mining work over that of exploration is observed in the Republic of Kazakhstan. It is also shown that the share of investments in geological exploration in the total investments in the mining sector is insignificant. The major part of the funds is invested in mineral extraction activities. In this connection, the paper proposes ways to improve administrative approaches to subsoil management in the Republic of Kazakhstan when granting subsoil use rights, in order to eliminate barriers for investors. The proposed improvements for the state subsoil management can have positive effect: investment growth due to improving the administrative approaches in the Republic’s state subsoil management, ensuring transparency of information, supporting new standards, a simplified procedure for obtaining subsoil use rights (licensing); reducing corruption in the field of geology and subsoil use and reducing labor costs for the implementation of state functions through the creation of a modern geological infrastructure and the use of innovative opportunities in the implementation of supervisory functions by the competent authorities; ensuring fair returns for the government from taxes, as well as obtaining fair returns by investors.

The study relevance is supported by the following: the need to improve procurement activities in accordance with the tasks set by the Government of the Republic of Kazakhstan, which indicate the need for radical revision of approaches to procurement in the quasi-public sector, natural monopolies, and subsoil use sector; the need to optimize NAC Kazatomprom JSC (the Company)'s expenses and reduce the cost of production in highly competitive situation at the natural uranium market through implementing category procurement strategy; the need to ensure efficiency and transparency of the Company's procurement through the implementation of category procurement strategy. The study aim is to substantiate effectiveness of the category procurement strategy implementation at uranium mining enterprises. The category procurement strategy is a completely new approach, which, unlike the current system, provides for achievement of economic efficiency throughout the entire life cycle of a product, work, or service. This system is being implemented for the first time in the Company and has no analogues in the country. The paper analyzed the current state of procurement activities of the uranium mining enterprises, identified and segmented problem areas of the activities, determined directions of their optimization. In addition, effectiveness of the category procurement strategy implementation at the enterprise was substantiated, and measures were developed to form the category procurement strategy in the Company for the main groups of goods.

Drilling and blasting operations (D&B) are the most difficult and laborious operations in the process of mineral extraction, requiring permanent development and upgrading of methods and equipment. The aim of the study is to substantiate the parameters of drilling and blasting drivage of horizontal and inclined (up to 12o) mine workings on the basis of high-performance self-propelled equipment and new designs of box cuts with cleaning explosive charges (0.2 kg of 6ZhV ammonite), placed in advance holes of 65 to 105 mm in diameter. The paper presents the results of the analysis of practical experience and scientific achievements in the field of drilling-andblasting rupture of solid media and continuum mechanics. The need for new designs of box cuts, reliability of which in the formation of high-quality (clean) cut cavity reaches 0.95-1.00, was substantiated. New design options of box cuts have been developed, the peculiarity of which consists in provision of sufficient compensation (peripheral) volume with the use of blast hole cut charges for blasting rupture of trapezoidal partitions, with the compensation volume factor of 2.50 to 1.34. Promising areas of research were shown using the example of complicated structure ore deposits and large faults in the Kirovograd ore district and crystalline rocks of the Ukrainian shield at the following mines of Ukraine: PJSC KZhRK, CJSC Sukhaya Balka (Kryvyi Rih), Vostok-Ruda LLC, SE VostGOK (Zheltye Vody), CJSC ZZhRK, etc. Promising areas of research were proposed using the example of complicated structure ore deposits typically formed at the junction of large faults; besides, the use of environmentally friendly emulsion explosives and self-propelled emulsion explosive chargers was recommended.

The information on history of in-situ metal leaching method (ISL) was given. The role of Russian scientists and research organizations in research into ISL processes was shown. Examples of ISL application at the mines of the USSR, the CIS and nonCIS countries with the implementation features were given. The main disadvantages of ISL were formulated: low rate of metal production and difficulty in monitoring the completeness of metal recovery into pregnant solution. It was noted that underground leaching of even well-crushed ores lasts for many years. This, under otherwise equal conditions, decreases attractiveness of ISL in comparison with traditional methods of metal mining. Well-known and new promising methods of the leaching process intensification for increasing the rate of metal extraction into solution were described. As illustrated by the North Caucasian deposits of the Sadon group, the expediency of ISL use for extracting the residual reserves, which would not be extracted by the traditional methods, was shown. The role of Professor I.A. Ostroushko in development and implementation of methods for extracting metals remained in the mined-out space of mines, in particular, by extracting metals from the Sadon deposits wastewater. Information on the current state of ISL application was given. The conclusion was made about insufficient use of this promising method in mining in some regions. For the first time, the details of the ISL general concept were clarified: the feasibility of ISL use not only in favorable conditions, but also at non-continuous geology and mineralization; ISL applicability for not only substandard ores (non-extractable by traditional mining methods), but also for balance reserves; ISL (block leaching) was proposed as an alternative to traditional mining methods in specific conditions, for example, at the North Caucasian complex ore deposits.

The problem of restoring the lost mining potential is of particular relevance for North Ossetia-Alania. For the first time, for solving the problem of the Sadon lead-zinc complex, in connection with depletion of reserves and decreasing grade of extracted polymetallic ores, the feasibility of exploiting the whole deposit by in-situ leaching (ISL) method was investigated. Commercial mineralization of the East Dzhimidon ore zone was characterized in relation to the technological features of the ore preparation for leaching. A comprehensive assessment of the compliance of the ores and the parameters of their position with the requirements of in-situ leaching protocols was given. An audit of the lead and zinc reserves of the Dzhimidon ore field was implemented, taking into account the increase in the reserves eligible for processing due to decreasing the cut-off grades. The theory for effective rock rupture provision to facilitate the subsequent metal was considered. The study was focused on priority separation of intact grains of the useful component from barren rock minerals, with selective energy consumption for breaking interatomic bonds along the intergrowth surfaces only. A criterion of ore blasting preparation (for ISL) was determined, namely, ensuring the level of energy impact, sufficient for breaking weakened intergranular bonds but insufficient for rupture of individual grains. For the first time, a mechanism for expanding mineral resource base through decreasing cut-off grades due to shifting from common underground mining methods to in-situ leaching was demonstrated. The priority of ensuring the quality of ore crushing for leaching through optimization of the blast energy parameters was shown. The ISL performance will be determined taking into account geological parameters of the deposits and ensuring the size of ore grain to be leached.

The growth of volume of tunneling, power supplied per job, and consumption of fuel and energy resources makes it necessary to increase energy performance of production processes with reducing energy losses. Tunneling conditions are determined by a combination of mutually influencing factors (geological, technological and organizational), and assessing their impact on tunneling energy performance requires a deep detailed study. For criterion assessment of tunneling performance, indicators of energy consumption, performance, and quality of tunneling performed by shift crews, allowing to objectively assess their work, were proposed. Indicators of process and specific power consumption in the process of tunneling vary over a wide range, therefore, to ensure smooth equipment operation, shift crews must adhere to the recommended indicators that determine the optimum rates of tunneling and enables adherence to permissible operation modes. Statistical models of energy performance indicators of heading sets of equipment operation were investigated using the example of the Severnaya coal mine. Indicators of energy consumption, energy performance, and tunneling (on shift basis) were proposed. Distribution laws have been determined for the main indicators characterizing tunneling energy performance. Recommendations have been developed to ensure sustainable operation of heading sets of equipment throughout the entire period of tunneling. Tunneling requires permanent monitoring its parameters and rates of advance, the quality of face preparation, timely maintenance and repair of machinery and equipment, control of the process through ensuring optimal operating modes of the heading sets of equipment.