Development and Justification of a Hydro-Impulse Method for Increasing Ore Permeability in Conditions of Uranium Borehole Production

Purpose. The research purpose is to increase the efficiency of borehole uranium mining by selecting special decolmating solutions and rational parameters of the technology for influencing the seam near-filter zone of geotechnological boreholes, as well as improving the filtration characteristics of the seam, depending on the mineralogical composition of ores and the structure of sediment-forming materials. Methods. The method of X-ray phase analysis was used to study the powders. The core material samples were studied on transparent sections using a LEICA DM 2500 P microscope. The content of the elemental composition of the ores and host rocks in the samples of the productive horizon was controlled using an atomic emission spectrometer. Findings. Based on the research results, quantitative-qualitative characteristics of the host rocks in the productive horizon, sedimentary formations from technological boreholes have been determined, revealing various levels in the productive horizon. It has been found that in the Campanian horizon boreholes, ores have a complex structure and multicomponent sedimentary formations, representing a mixture of sediments of mechanical-chemical origin. Originality. The results of quantitative-qualitative, microscopic, thermal research methods of the characteristics of ore-bearing rocks from various horizons at the Syr Darya depression uranium deposit have been studied and comparatively analyzed. The sedimentary formations of technological boreholes in the productive Santonian, Maastrichtian, Campanian horizons of the Northern Kharasan field, Syr Darya depression, have also been sampled and studied. The choice of the most appropriate composition of chemical reagents for dissolution and prevention of sedimentary formation in porous media has been substan-tiated by the microscopic research method. Practical implications. A detailed study and comparative analysis of the characteristics of ores and host rocks in various productive horizons makes it possible to more accurately plan the mining of blocks, minimizing emerging risks. Using the developed combined technology for intensifying borehole uranium mining, it is possible to increase the efficiency of borehole uranium mining and reduce its operating costs. At the same time, the ecological and industrial safety of the work of intensi-fying the leaching uranium ores increases.

Section: Share Production Of Uranium By Countries Of the Worldmentioning

confidence: 99%

Selecting the rational parameters for restoring filtration characteristics of ores during borehole mining of uranium depositst

Kenzhetaev¹,

Togizov²,

Абдраймова³

et al. 2022

“…The impact of the mining depth on the stress-strain state of the mass and the parameters of main structural elements of mining blocks are studied in many scientific works, in particular, in researchers from Ukraine [14]- [17] and foreign researchers [18]- [22]. Special attentions are given to providing readiness for mining [23]- [25].…”

Section: Research and Publications Analysismentioning

confidence: 99%

Methodology enhancement for determining parameters of room systems when mining uranium ore in the SE “SkhidGZK” underground mines, Ukraine

Stupnik¹,

Kalinichenko²,

Fedko³

et al. 2022

Purpose. The present paper aims to enhance methodology for determining the safety and stability parameters of room mining systems with backfilling of the mined-out area when mining uranium ores in underground mines of the State Enterprise “Skhidnyi Mining and Beneficiation Plant” (SE “SkhidGZK”). Methods. The analytical research method used in the presented paper includes the analysis of previous relevant instructions and reports on the research performed at the SE “SkhidGZK”, as well as publications on the subject, operational geological survey documentation containing monitoring data on the stress-strain state of the rock mass surrounding the formed cavities and the actual state of the mined-out blocks in all underground mines of SE “SkhidGZK”. Findings. The research performed enables development of a new instruction for determining the safety and stability parameters of the room systems with backfilling when mining uranium ores in the SE “SkhidGZK” underground mines. Based on the developed new instruction, the stability of outcrops in mined-out rooms has been calculated, considering the actual time of their life. The obtained parameters fully correspond to actual stability of rooms in blocks of all underground mines. This indicates that the new instruction is more advanced as compared to the current Instruction and its implementation will contribute to mine safety enhancement. Originality. The increased depth of mining uranium ore in the SE “SkhidGZK” underground mines and the increase in lifetime of mined-out rooms require regular adjustment of the methodology for determining their safety and stability parameters. Based on the accumulated production experience, the observations conducted and a thorough analysis of the actual state of cavities, new and adjusted current dependences have been obtained that more accurately consider the impact of both determined factors and those unprovisioned in the current Instruction for determining the safety and stability parameters of rooms. Practical implications. The advanced methodology for determining the safety and stability parameters of room systems in comparison with the methodology described in the current Instruction at the “SkhidGZK” underground mines provides higher accuracy when determining the design parameters of rooms in the stoping blocks and greater reliability of predictive stability of both individual outcrops and rooms in general.

“…Currently, in the geotechnology of metals by in-situ leaching method, various oxidizers are used, such as atmospheric oxygen, hydrogen peroxide, sodium nitrite (NaNO2) and potassium bichromate (K2Cr2O70) and others [9], [10].…”

Section: Introductionmentioning

confidence: 99%

Investigation of the solid oxidizer effect on the metal geotechnology efficiency

Yussupov,

Aben,

Akhmetkanov

et al. 2023

Purpose. The research is aimed at increasing the useful component content in a pregnant solution during in-situ leaching (ISL) using a solid oxidizer and increasing the ferric iron concentration in the leaching solution based on laboratory research. Methods. Laboratory research is performed on a specially developed model electrolyzer for obtaining comparative data on divalent iron oxidation to trivalent iron and the change in the useful component content in a pregnant solution. Firstly, tests are conducted with a basic leaching solution, then on the oxidation of the leaching solution with a solid oxidizer in the form of a lead dioxide plate. Tests are conducted by changing sulphuric acid concentration within 5-50 g/l, amount of divalent iron ions in the solution from 0.5 up to 4.0 g, lead dioxide plate surface area from 19 to 76 cm2. The leaching time is up to 10 hours. Findings. The results of laboratory research on determining the oxidation degree of divalent iron ions and change in the oxidation-reduction potential (ORP) depending on the sulphuric acid concentration and on the initial concentration of divalent iron ions in the initial solution are presented. With a change in the sulphuric acid concentration from 5 to 50 g/l, the oxidation value of divalent iron ions increases from 26.5 to 96.5%, and with an increase in the initial solution concentration of divalent iron, the oxidation degree of divalent iron naturally decreases from 95.2 to 58.8%. In the initial leaching solution, the divalent solution concentration is 312 mg/l, and that of the trivalent solution is 288 mg/l. After oxidation with a solid oxidizer, the divalent and trivalent iron concentrations are 56 and 392 mg/l, respectively. In the course of further laboratory research using core materials from a uranium deposit, it has been revealed that when leaching with a basic solution, the uranium content in the pregnant solution is 19.36 mg/l, and when leaching with a solution after oxidation with a solid oxidizer, it is 27.9 mg/l, which is by 8.54 mg/l more. Originality. New dependences have been determined of the oxidation degree of divalent iron ions to trivalent one on the sulphuric acid concentration and on the initial concentration of divalent iron ions, as well as the useful component content in the pregnant solution on the leaching time when using a solid oxidizer. Practical implications. Using of a solid oxidizer, it is possible to increase the trivalent iron concentration in the leaching solution and the useful component content in the pregnant solution compared with the basic technology, thereby reducing the time of mining uranium reserves. Proposed technology is environmentally friendly, with low capital costs.