Pub Date : 2023-06-30DOI: 10.33271/mining17.02.112
Nikolina Račić, T. Malvić
Purpose. This paper focuses on the comparison of Ni and Pb concentrations in air and soil pollution in the Zagreb area. Due to the very limited amount of publicly available data from soil analysis samples, 2016 and 2019 were chosen as the best possible indicators of related changes in metal concentrations in soil and air. Methods. Testing the normality of Ni and Pb concentrations in the total deposited matter (TDM) confirmed the feasibility of using two parametric statistical tools – the Pearson correlation coefficient and the t-test. The Inverse Distance Weighting (IDW) interpolation method was selected as the best approach for a small number of measurements. Findings. The insufficient amount of data is the main shortcoming for urban health policy in a large area like Zagreb. The small number of air measurement stations and especially soil sampling sites cannot lead to any reliable conclusions about urban pollutants, their activity over time and direct links to soil toxic degradation based on statistical or geological methods and analyses. However, there is no doubt that urban pollution sources fill the soil with accumulated toxic elements such as Ni and Pb, especially in suburban areas located along the paths of the dominant wind directions. Originality. This is an original research that for the first time statistically analyzes and maps publicly available air and soil pollution data for the period 2016-2019. Practical implications. This research is a necessary step in determining the future planning of air and soil measurement stations in the Zagreb urban area.
{"title":"Relation between air and soil pollution based on statistical analysis and interpolation of Nickel (Ni) and Lead (Pb): Case study of Zagreb, Croatia","authors":"Nikolina Račić, T. Malvić","doi":"10.33271/mining17.02.112","DOIUrl":"https://doi.org/10.33271/mining17.02.112","url":null,"abstract":"Purpose. This paper focuses on the comparison of Ni and Pb concentrations in air and soil pollution in the Zagreb area. Due to the very limited amount of publicly available data from soil analysis samples, 2016 and 2019 were chosen as the best possible indicators of related changes in metal concentrations in soil and air. Methods. Testing the normality of Ni and Pb concentrations in the total deposited matter (TDM) confirmed the feasibility of using two parametric statistical tools – the Pearson correlation coefficient and the t-test. The Inverse Distance Weighting (IDW) interpolation method was selected as the best approach for a small number of measurements. Findings. The insufficient amount of data is the main shortcoming for urban health policy in a large area like Zagreb. The small number of air measurement stations and especially soil sampling sites cannot lead to any reliable conclusions about urban pollutants, their activity over time and direct links to soil toxic degradation based on statistical or geological methods and analyses. However, there is no doubt that urban pollution sources fill the soil with accumulated toxic elements such as Ni and Pb, especially in suburban areas located along the paths of the dominant wind directions. Originality. This is an original research that for the first time statistically analyzes and maps publicly available air and soil pollution data for the period 2016-2019. Practical implications. This research is a necessary step in determining the future planning of air and soil measurement stations in the Zagreb urban area.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46245380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-30DOI: 10.33271/mining17.01.035
Aibek Mussin, A. Imashev, Azamat Matayev, Yerkebulan Abeuov, Nurlan Shaike, A. Kuttybayev
Purpose. The research purpose is to study the effectiveness of artificial maintenance of the mined-out space based on the use of cable bolts to reduce the dilution coefficient when mining low-thickness ore bodies. Methods. Geotechnical mapping of the rock mass according to the Q, RMR, RQD and GSI rating classifications is conducted, as well as a linear survey of the fracture system in the hanging wall and footwall rocks is performed using a rock compass and the GEO ID application. Numerical analysis by the limit equilibrium method in the Unwedge software package is applied to determine the safety factor of a mass divided by fractures into wedges. Using a Schmidt test hammer, the uniaxial compressive strength of the mass rocks has been determined. The full-scale studies have been conducted using cable support in the conditions of the Akbakai deposit. Findings. It has been revealed that the footwall rocks are in a stable state, while the safety factor of the hanging wall rocks is 0.98, which requires artificial maintenance using cable bolts. The cable support parameters are calculated taking into account nonuniform distribution of horizontal and vertical stresses in the rock mass. It has been determined that when strengthening the hanging wall with cable bolts in inclined veins with a dip angle of up to 40º, the average ore dilution is 66.1%, and that of previously mined without fastening is 68.7%. In similar experiments in steep-dipping veins with a dip angle of more than 60º, dilution decreases from 62.8 to 48.7%. Originality. It has been revealed that in the conditions of the Akbakai deposit, cable fastening of the hanging wall rocks is effective at an ore deposit dip angle of more than 60º, at which the mined ore dilution coefficient decreases. Practical implications. The research results can be used to increase the stability of hanging wall rocks when mining low-thickness ore bodies with a sublevel caving system.
{"title":"Reduction of ore dilution when mining low-thickness ore bodies by means of artificial maintenance of the mined-out area","authors":"Aibek Mussin, A. Imashev, Azamat Matayev, Yerkebulan Abeuov, Nurlan Shaike, A. Kuttybayev","doi":"10.33271/mining17.01.035","DOIUrl":"https://doi.org/10.33271/mining17.01.035","url":null,"abstract":"Purpose. The research purpose is to study the effectiveness of artificial maintenance of the mined-out space based on the use of cable bolts to reduce the dilution coefficient when mining low-thickness ore bodies. Methods. Geotechnical mapping of the rock mass according to the Q, RMR, RQD and GSI rating classifications is conducted, as well as a linear survey of the fracture system in the hanging wall and footwall rocks is performed using a rock compass and the GEO ID application. Numerical analysis by the limit equilibrium method in the Unwedge software package is applied to determine the safety factor of a mass divided by fractures into wedges. Using a Schmidt test hammer, the uniaxial compressive strength of the mass rocks has been determined. The full-scale studies have been conducted using cable support in the conditions of the Akbakai deposit. Findings. It has been revealed that the footwall rocks are in a stable state, while the safety factor of the hanging wall rocks is 0.98, which requires artificial maintenance using cable bolts. The cable support parameters are calculated taking into account nonuniform distribution of horizontal and vertical stresses in the rock mass. It has been determined that when strengthening the hanging wall with cable bolts in inclined veins with a dip angle of up to 40º, the average ore dilution is 66.1%, and that of previously mined without fastening is 68.7%. In similar experiments in steep-dipping veins with a dip angle of more than 60º, dilution decreases from 62.8 to 48.7%. Originality. It has been revealed that in the conditions of the Akbakai deposit, cable fastening of the hanging wall rocks is effective at an ore deposit dip angle of more than 60º, at which the mined ore dilution coefficient decreases. Practical implications. The research results can be used to increase the stability of hanging wall rocks when mining low-thickness ore bodies with a sublevel caving system.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48313512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-30DOI: 10.33271/mining17.01.129
Abzal Zhienbayev, M. Balpanova, Zhanar Asanova, M. Zharaspaev, Rustem Nurkasyn, Bolegen Zhakupov
Purpose. To ensure the roof span stability in terms of room-and-pillar system of mining taking into consideration the calculations, modelling, and statistic analysis of factual rock falls from the roof. Methods. Analysis of inelastic deformations to define overall displacement of a thin-layer roof of the chamber being 9 m wide was performed with the help of software complex RS2. To estimate the effect of chamber spans on the roof stability, a problem was considered in two variants where chamber width was 8 and then 7 m. The results were analyzed in terms of strength factor of the interchamber pillars. Statistic analysis of the roof stability loss for the chambers was carried out according to the results of monitoring of a state of the worked-out space in the context of the Zhaman-Aibat deposit. The obtained data were compared in terms of chamber roof spans being 9-7 m. Findings. The performed studies make it possible to state that the reduction of chamber spans down to 7 m decreases the roof deflection up to 2 cm and ensures stability of both chamber roof and worked-out space by 13 times; in its turn, that results in safe conditions while stoping. Optimal parameters of the roof span stability for chambers and safe mining conditions were substantiated basing on computer modelling and statistic analysis of the results of geotechnical monitoring of a state of worked-out space at the Zhaman-Aibat deposit. Originality. The regularity of changes in the safety factor of the peripheral part of a chamber was substantiated depending on the chamber width (7, 8, and 9 m) and considering the distance from the contoured chamber (m). Reduction of the chamber span by 1 m (from 9 to 8 m) reduces roof deflection by 2 times (up to 5 cm); moreover, breaking depth in the roof experiences considerable reduction – up to 1.75 m. Reduction of the chamber span by 1 m more (from 8 to 7 m) reduces the roof deflection up to 2 cm; breaking depth in the roof decreases considerably as well – up to 1.33 m. Practical implications. The proposed variant of chamber span reduction can decrease significantly the total area of rock falls and ensure stability of the worked-out space of the Zhomart mine where roof stability is the weakest element on the mining system. The obtained results can be the basis for the development of methodological recommendations to calculate mining parameters at the Zhaman-Aibat deposit as well as at other deposits with medium roof stability.
{"title":"Analysis of the roof span stability in terms of room-and-pillar system of ore deposit mining","authors":"Abzal Zhienbayev, M. Balpanova, Zhanar Asanova, M. Zharaspaev, Rustem Nurkasyn, Bolegen Zhakupov","doi":"10.33271/mining17.01.129","DOIUrl":"https://doi.org/10.33271/mining17.01.129","url":null,"abstract":"Purpose. To ensure the roof span stability in terms of room-and-pillar system of mining taking into consideration the calculations, modelling, and statistic analysis of factual rock falls from the roof. Methods. Analysis of inelastic deformations to define overall displacement of a thin-layer roof of the chamber being 9 m wide was performed with the help of software complex RS2. To estimate the effect of chamber spans on the roof stability, a problem was considered in two variants where chamber width was 8 and then 7 m. The results were analyzed in terms of strength factor of the interchamber pillars. Statistic analysis of the roof stability loss for the chambers was carried out according to the results of monitoring of a state of the worked-out space in the context of the Zhaman-Aibat deposit. The obtained data were compared in terms of chamber roof spans being 9-7 m. Findings. The performed studies make it possible to state that the reduction of chamber spans down to 7 m decreases the roof deflection up to 2 cm and ensures stability of both chamber roof and worked-out space by 13 times; in its turn, that results in safe conditions while stoping. Optimal parameters of the roof span stability for chambers and safe mining conditions were substantiated basing on computer modelling and statistic analysis of the results of geotechnical monitoring of a state of worked-out space at the Zhaman-Aibat deposit. Originality. The regularity of changes in the safety factor of the peripheral part of a chamber was substantiated depending on the chamber width (7, 8, and 9 m) and considering the distance from the contoured chamber (m). Reduction of the chamber span by 1 m (from 9 to 8 m) reduces roof deflection by 2 times (up to 5 cm); moreover, breaking depth in the roof experiences considerable reduction – up to 1.75 m. Reduction of the chamber span by 1 m more (from 8 to 7 m) reduces the roof deflection up to 2 cm; breaking depth in the roof decreases considerably as well – up to 1.33 m. Practical implications. The proposed variant of chamber span reduction can decrease significantly the total area of rock falls and ensure stability of the worked-out space of the Zhomart mine where roof stability is the weakest element on the mining system. The obtained results can be the basis for the development of methodological recommendations to calculate mining parameters at the Zhaman-Aibat deposit as well as at other deposits with medium roof stability.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45650713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-30DOI: 10.33271/mining17.01.101
S. Matkivskyi
Purpose. The research purpose is to increase the efficiency of development of gas condensate fields with a high condensate yield in the reservoir gas and to develop optimal ways of increasing their hydrocarbon recovery. Methods. The effectiveness of the implementation of reservoir pressure maintenance technologies using dry gas for the development of gas condensate fields with a high condensate yield in the reservoir gas is studied on the basis of a heterogeneous 3D model using the Schlumberger Eclipse and Petrel software packages. The technological indicators of the development of gas-condensate reservoir are studied for different pressure values at the beginning of the dry gas injection. Calculations were made for pressures at the beginning of injection at the level of: 1.0 Рinit; 0.8 Рinit; 0.6 Рinit; 0.4 Рinit; 0.2 Рinit. Findings. It has been determined that when the dry gas is injected into a gas-condensate reservoir, reservoir pressure is maintained at a significantly higher level than it is in the case of depletion. This ensures stable operation of production wells over a longer period of the reservoir development. According to the research results, it should be noted that in the case of implementation of the reservoir pressure maintenance technology, a part of the precipitated condensate is transferred to the gas phase, which makes it necessary to extract it together with the reservoir gas. Based on the modeling results, the ultimate condensate recovery factor have been calculated. The calculation results indicate that in the case of the cycling process implementation, the ultimate condensate recovery factor of the gas-condensate reservoir increases by 7.26% compared to depletion development. Originality. Based on the calculation data analysis, the optimal pressure value at the beginning of dry gas injection into a gas-condensate reservoir has been determined, which is 0.842 Рinit. Practical implications. The use of the conducted research results will optimize the development system of gas-condensate fields with high initial condensate yield in the reservoir gas and increase the efficiency of development the explored hydrocarbon reserves in the conditions of a significant shortage of hydrocarbon raw materials in Ukraine. The conducted research results indicate the high technological efficiency of the reservoir pressure maintenance technology using dry gas.
{"title":"Optimization of gas recycling technique in development of gas-condensate fields","authors":"S. Matkivskyi","doi":"10.33271/mining17.01.101","DOIUrl":"https://doi.org/10.33271/mining17.01.101","url":null,"abstract":"Purpose. The research purpose is to increase the efficiency of development of gas condensate fields with a high condensate yield in the reservoir gas and to develop optimal ways of increasing their hydrocarbon recovery. Methods. The effectiveness of the implementation of reservoir pressure maintenance technologies using dry gas for the development of gas condensate fields with a high condensate yield in the reservoir gas is studied on the basis of a heterogeneous 3D model using the Schlumberger Eclipse and Petrel software packages. The technological indicators of the development of gas-condensate reservoir are studied for different pressure values at the beginning of the dry gas injection. Calculations were made for pressures at the beginning of injection at the level of: 1.0 Рinit; 0.8 Рinit; 0.6 Рinit; 0.4 Рinit; 0.2 Рinit. Findings. It has been determined that when the dry gas is injected into a gas-condensate reservoir, reservoir pressure is maintained at a significantly higher level than it is in the case of depletion. This ensures stable operation of production wells over a longer period of the reservoir development. According to the research results, it should be noted that in the case of implementation of the reservoir pressure maintenance technology, a part of the precipitated condensate is transferred to the gas phase, which makes it necessary to extract it together with the reservoir gas. Based on the modeling results, the ultimate condensate recovery factor have been calculated. The calculation results indicate that in the case of the cycling process implementation, the ultimate condensate recovery factor of the gas-condensate reservoir increases by 7.26% compared to depletion development. Originality. Based on the calculation data analysis, the optimal pressure value at the beginning of dry gas injection into a gas-condensate reservoir has been determined, which is 0.842 Рinit. Practical implications. The use of the conducted research results will optimize the development system of gas-condensate fields with high initial condensate yield in the reservoir gas and increase the efficiency of development the explored hydrocarbon reserves in the conditions of a significant shortage of hydrocarbon raw materials in Ukraine. The conducted research results indicate the high technological efficiency of the reservoir pressure maintenance technology using dry gas.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":"29 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69439022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-30DOI: 10.33271/mining17.01.067
Rahma Khadri, A. Khedidja, Brinis Nafaa, Kharroubi Maha
Purpose. The neritic aquifer that extends between Hammam Bradaa and El Fedjoudj, despite its faulted and in places karstified structure, due toits capacity and lateral extension represent a strategic resource for the region. Its waters are used for drinking water supply in the neighboring towns: Heliopolis, Guelaat Bousbaa, Nechmaya and El Fedjoudj, as well as in part of the Annaba wilaya. These neritic limestones outcrop at Djebel Debagh and Bouzitoune. Methods. In order to better study the potential of this aquifer, it is essential to identify its geometry and structure by analyzing the geological data, mechanical drilling data and geophysical data analysis through an electrical survey campaign. Findings. The main results indicate that the study area has identified two important aquifer formations: a formation in the Mio-Plio-Quaternary alluvium consisting of clays, marls, gravel and sand; the second is a deep carbonate aquifer composed of fissured and karstified neritic limestone of the Cretaceous age of variable depth ranging within 50 and 350 m. Originality. The originality of the study is in the fact that the studied area is characterized by the presence of thick, fractured and karstified carbonate formations, which are intensively tectonized and have significant aquifer potential. Practical implications. The correlation of geological data with geophysical data made it possible to conclude that the stu-died area is a sedimentary basin bounded by faults predominantly oriented to the south-west and north-east, forming a highly fractured unit consisting of horsts and grabens. The significant water potential reservoir is formed essentially by carbonate geological formations, highly fractured with the presence of karst forms represented by resistant horizons.
{"title":"Geophysical and geological contribution to determining the neritic limestone aquifer structure of Hammam Bradaa – El Fedjoudj (Seybouse medium), Northeastern Algeria","authors":"Rahma Khadri, A. Khedidja, Brinis Nafaa, Kharroubi Maha","doi":"10.33271/mining17.01.067","DOIUrl":"https://doi.org/10.33271/mining17.01.067","url":null,"abstract":"Purpose. The neritic aquifer that extends between Hammam Bradaa and El Fedjoudj, despite its faulted and in places karstified structure, due toits capacity and lateral extension represent a strategic resource for the region. Its waters are used for drinking water supply in the neighboring towns: Heliopolis, Guelaat Bousbaa, Nechmaya and El Fedjoudj, as well as in part of the Annaba wilaya. These neritic limestones outcrop at Djebel Debagh and Bouzitoune. Methods. In order to better study the potential of this aquifer, it is essential to identify its geometry and structure by analyzing the geological data, mechanical drilling data and geophysical data analysis through an electrical survey campaign. Findings. The main results indicate that the study area has identified two important aquifer formations: a formation in the Mio-Plio-Quaternary alluvium consisting of clays, marls, gravel and sand; the second is a deep carbonate aquifer composed of fissured and karstified neritic limestone of the Cretaceous age of variable depth ranging within 50 and 350 m. Originality. The originality of the study is in the fact that the studied area is characterized by the presence of thick, fractured and karstified carbonate formations, which are intensively tectonized and have significant aquifer potential. Practical implications. The correlation of geological data with geophysical data made it possible to conclude that the stu-died area is a sedimentary basin bounded by faults predominantly oriented to the south-west and north-east, forming a highly fractured unit consisting of horsts and grabens. The significant water potential reservoir is formed essentially by carbonate geological formations, highly fractured with the presence of karst forms represented by resistant horizons.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48671653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-30DOI: 10.33271/mining17.01.043
L. Vasyliev, M. Malich, D. Vasyliev, V. Katan, Zahar Rizo
Purpose is to improve analytical technique to calculate strength of cylindrical rock samples taking into consideration standard horizontal stresses. Methods. Mathematical modeling of cylindrical rock sample breakage under the truncated-wedge destruction was performed taking into consideration the standard horizontal stresses using four experimental characteristics (i.e. k being shear strength; fс and μ being contact and internal friction coefficients; and Е being elasticity modulus) as well as comparing the design strength with experimental data obtained in the process of uniaxial compression. Findings. The technique makes it possible to identify both maximum strength and residual strength of cylindrical rock samples using four indicators of properties which can be simply defined by experiment. Comparison of the analytical strength limits and experimental data, obtained in terms of uniaxial compression, supports the idea of high efficiency of the proposed technique. Originality. For the first time, analytical modeling of cylindrical rock sample breakage has been performed in terms of the truncated-wedge destruction taking into consideration the standard horizontal stresses as well as contact and internal friction parameters. Practical implications. The technique advantage is to apply promptly the calculation results in the context of industrial enterprises since their environment helps apply simple procedures to define indices of physiсomechanical characteristics of rocks for determination of stability of underground structures and reduction of energy consumption while disintegrating in open pits and mining and processing complexes.
{"title":"Improving a technique to calculate strength of cylindrical rock samples in terms of uniaxial compression","authors":"L. Vasyliev, M. Malich, D. Vasyliev, V. Katan, Zahar Rizo","doi":"10.33271/mining17.01.043","DOIUrl":"https://doi.org/10.33271/mining17.01.043","url":null,"abstract":"Purpose is to improve analytical technique to calculate strength of cylindrical rock samples taking into consideration standard horizontal stresses. Methods. Mathematical modeling of cylindrical rock sample breakage under the truncated-wedge destruction was performed taking into consideration the standard horizontal stresses using four experimental characteristics (i.e. k being shear strength; fс and μ being contact and internal friction coefficients; and Е being elasticity modulus) as well as comparing the design strength with experimental data obtained in the process of uniaxial compression. Findings. The technique makes it possible to identify both maximum strength and residual strength of cylindrical rock samples using four indicators of properties which can be simply defined by experiment. Comparison of the analytical strength limits and experimental data, obtained in terms of uniaxial compression, supports the idea of high efficiency of the proposed technique. Originality. For the first time, analytical modeling of cylindrical rock sample breakage has been performed in terms of the truncated-wedge destruction taking into consideration the standard horizontal stresses as well as contact and internal friction parameters. Practical implications. The technique advantage is to apply promptly the calculation results in the context of industrial enterprises since their environment helps apply simple procedures to define indices of physiсomechanical characteristics of rocks for determination of stability of underground structures and reduction of energy consumption while disintegrating in open pits and mining and processing complexes.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47025410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-30DOI: 10.33271/mining17.01.001
V. Bondarenko, I. Salieiev, I. Kovalevska, V. Chervatiuk, D. Malashkevych, M. Shyshov, Volodymyr Chernyak
Purpose. The research purpose is to develop a concept for complex mining of mineral resources from coal mines using the example of PJSC DTEK Pavlohradvuhillia mines with a transition to multi-product production of clean drinking water, utilization of methane, secondary coal from rock dumps and sludge reservoirs, low-potential thermal energy of mine groundwaters and associated raw materials from desalination waste. Methods. The research uses an integrated approach, which includes an analysis of existing experience and available complex coal mining technologies, laboratory studies of mine water desalination technology by the reverse osmosis method with thermal distillation of concentrated brine, and chemical analysis using ElvaX laboratory equipment. Findings. This paper presents the research results of a comprehensive analysis of mineral raw material resources related to coal mining. The technically achievable energy potential that can be produced from the secondary coal of rock dumps and sludge reservoirs has been determined, which in total is 183.3 TJ. The annual heat potential of methane gas utilization has been estimated, which in total of PJSC DTEK Pavlohradvuhillia’s mines reaches 7.1 PJ. The possibility of extracting up to 1.12 TJ/year of associated thermal energy from the water-drainage installation of mine complexes has been determined. For the conditions of the Zakhidno-Donbaska mine, the authors of the paper have developed a technological scheme for the water preparation process by the reverse osmosis with the desalination brine treatment by the method of multistage evaporation on adiabatic evaporators. Originality. For the first time, the energy flows related to coal mining technology have been comprehensively analyzed for the possibility of their joint use to cover the needs of the mine complex. The prospects for complex mining of mineral resources have been assessed based on the adaptation of the mine complex production facilities to the multi-product production of clean drinking water, utilization of methane gas, low-potential thermal energy from mine groundwaters and secondary raw materials of desalination waste. Practical implications. The proposed set of technological solutions will ensure the sustainable development and diversification of the production of PJSC DTEK Pavlohradvuhillia coal-mining enterprises, as well as the effective transformation of coal-mining cities during the period of transition from mono-product production to the creation of multi-business production complexes that comply with ESG principles. The creation of multi-product mine complexes capable of producing not only coal, but also heat and associated mineral raw material resources, should become a guarantee of stable social-economic development of coal-mining regions.
{"title":"A new concept for complex mining of mineral raw material resources from DTEK coal mines based on sustainable development and ESG strategy","authors":"V. Bondarenko, I. Salieiev, I. Kovalevska, V. Chervatiuk, D. Malashkevych, M. Shyshov, Volodymyr Chernyak","doi":"10.33271/mining17.01.001","DOIUrl":"https://doi.org/10.33271/mining17.01.001","url":null,"abstract":"Purpose. The research purpose is to develop a concept for complex mining of mineral resources from coal mines using the example of PJSC DTEK Pavlohradvuhillia mines with a transition to multi-product production of clean drinking water, utilization of methane, secondary coal from rock dumps and sludge reservoirs, low-potential thermal energy of mine groundwaters and associated raw materials from desalination waste. Methods. The research uses an integrated approach, which includes an analysis of existing experience and available complex coal mining technologies, laboratory studies of mine water desalination technology by the reverse osmosis method with thermal distillation of concentrated brine, and chemical analysis using ElvaX laboratory equipment. Findings. This paper presents the research results of a comprehensive analysis of mineral raw material resources related to coal mining. The technically achievable energy potential that can be produced from the secondary coal of rock dumps and sludge reservoirs has been determined, which in total is 183.3 TJ. The annual heat potential of methane gas utilization has been estimated, which in total of PJSC DTEK Pavlohradvuhillia’s mines reaches 7.1 PJ. The possibility of extracting up to 1.12 TJ/year of associated thermal energy from the water-drainage installation of mine complexes has been determined. For the conditions of the Zakhidno-Donbaska mine, the authors of the paper have developed a technological scheme for the water preparation process by the reverse osmosis with the desalination brine treatment by the method of multistage evaporation on adiabatic evaporators. Originality. For the first time, the energy flows related to coal mining technology have been comprehensively analyzed for the possibility of their joint use to cover the needs of the mine complex. The prospects for complex mining of mineral resources have been assessed based on the adaptation of the mine complex production facilities to the multi-product production of clean drinking water, utilization of methane gas, low-potential thermal energy from mine groundwaters and secondary raw materials of desalination waste. Practical implications. The proposed set of technological solutions will ensure the sustainable development and diversification of the production of PJSC DTEK Pavlohradvuhillia coal-mining enterprises, as well as the effective transformation of coal-mining cities during the period of transition from mono-product production to the creation of multi-business production complexes that comply with ESG principles. The creation of multi-product mine complexes capable of producing not only coal, but also heat and associated mineral raw material resources, should become a guarantee of stable social-economic development of coal-mining regions.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42643443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-30DOI: 10.33271/mining17.01.093
S. Krasnovyd, Andrii Konchits, B. Shanina, M. Valakh, V. Yukhymchuk, M. Skoryk, O. Molchanov, Oleksandr Kamchatny
Purpose is to analyze influence mechanisms of physicochemical coal properties on the degree of outburst risk as well as desorption kinetics of methane. Methods of scanning electron microscopy (SEM), electron paramagnetic resonance (EPR), nuclear magnetic resonance (NMR), infrared spectroscopy (IR) and Raman scattering (RS) have been applied. The samples have been taken from Donbas coal seams varying in their ranks (i.e. carbonization degree). Findings. It has been identified that in the context of outburst hazardous zones, the ratio between integral intensity of spectral RS bands D and G, K = I(D)/I(G) shows abnormal dependence upon the nominal amount of volatile compounds connected with the impact by iron impurities. It has been defined that within the ferriferous coal samples, concentration of spins ns (i.e. the broken carbon bonds) correlates with iron content. Methane adsorption/desorption processes in the studied coal samples have been studied with the help of NMR method; in addition, they have been described using superposition of diffusion and filtration mechanisms. Originality. It has been understood that high iron content is typical for coal with a greater outburst hazardous degree. The abovementioned iron content and I(D)/I(G) and Ns correlation between the values determines the key role of iron impurities for coal metamorphism processes. For the first time, correlation between the outburst hazardous degree of coal seam and intensity of 3030 cm-1 IR band, stipulated by aromatic CH groups where hydrogen is in atomic status, has been identified. Practical implications. Predictability of outburst risk has been improved in the context of coal seam mining.
{"title":"Coal from the outburst hazardous mine seams: Spectroscopic study","authors":"S. Krasnovyd, Andrii Konchits, B. Shanina, M. Valakh, V. Yukhymchuk, M. Skoryk, O. Molchanov, Oleksandr Kamchatny","doi":"10.33271/mining17.01.093","DOIUrl":"https://doi.org/10.33271/mining17.01.093","url":null,"abstract":"Purpose is to analyze influence mechanisms of physicochemical coal properties on the degree of outburst risk as well as desorption kinetics of methane. Methods of scanning electron microscopy (SEM), electron paramagnetic resonance (EPR), nuclear magnetic resonance (NMR), infrared spectroscopy (IR) and Raman scattering (RS) have been applied. The samples have been taken from Donbas coal seams varying in their ranks (i.e. carbonization degree). Findings. It has been identified that in the context of outburst hazardous zones, the ratio between integral intensity of spectral RS bands D and G, K = I(D)/I(G) shows abnormal dependence upon the nominal amount of volatile compounds connected with the impact by iron impurities. It has been defined that within the ferriferous coal samples, concentration of spins ns (i.e. the broken carbon bonds) correlates with iron content. Methane adsorption/desorption processes in the studied coal samples have been studied with the help of NMR method; in addition, they have been described using superposition of diffusion and filtration mechanisms. Originality. It has been understood that high iron content is typical for coal with a greater outburst hazardous degree. The abovementioned iron content and I(D)/I(G) and Ns correlation between the values determines the key role of iron impurities for coal metamorphism processes. For the first time, correlation between the outburst hazardous degree of coal seam and intensity of 3030 cm-1 IR band, stipulated by aromatic CH groups where hydrogen is in atomic status, has been identified. Practical implications. Predictability of outburst risk has been improved in the context of coal seam mining.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45992065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-30DOI: 10.33271/mining17.01.028
Ye.V. Semenenko, O. Medvedieva, V. Medianyk, Borys Bluyss, Oleksandr Khaminich
Purpose. The research purpose is to develop a mathematical model of a pressureless flow in a channel with the occurrence in some areas of overflow layer through the wall. Using this model, it is possible to calculate the overflow layer height and length, as well as the change in flow rate in the channel due to the withdrawal of part of the fluid as a result of the overflow. Methods. The research uses a comprehensive multi-stage analytical approach. Firstly, in order to develop a mathematical model for a pressureless flow in the channel with the occurrence in some areas of overflow layer through the wall, this research analytically determines the dependence of the flow rate through the channel wall based on formulas for calculating the weir discharge coefficient. At the second stage, a mathematical model of a hydraulic mixture pressureless flow in a rectangular channel with an overflow through the wall is developed to determine the parameters and flow regimes of the stream. Findings. The dependences of the dimensionless height of the overflow through the channel wall and the effective critical flow depth on the dimensionless current channel length have been obtained for various values of the acting force parameters and the process parameter of the fluid overflow through the channel wall. This made it possible to study the dynamics of changes in these values along the channel for various values of the specified parameters, and to assess the degree of influence of the relevant factors on the characteristics of the pressureless flow along the channel and the process of fluid overflow through wall. Originality. For the first time, the model of the pressureless flow in the channel is generalized for the case of occurrence in some areas of overflow layer through the wall, when the length and height of the overflow layer are not determined by a hole in the side surface, but are controlled by a decrease in the corresponding flow rate. For the first time, this model makes it possible to calculate the height and length of the overflow layer and the change in the flow rate in the channel due to the withdrawal of part of the fluid as a result of the overflow in cases of overflowing condition of the channel with the stream under unstable and non-calculated flow regimes. Practical implications. The mathematical model and the calculation results can be used to ensure the environmental safety of the logistics systems of mining enterprises, as well as to assess the volume of the environmental pollution in case of overflowing through the wall of the channels of pressureless hydraulic transportation of waste from mineral processing and metallurgical plants.
{"title":"Research into the pressureless flow in hydrotechnical systems at mining enterprises","authors":"Ye.V. Semenenko, O. Medvedieva, V. Medianyk, Borys Bluyss, Oleksandr Khaminich","doi":"10.33271/mining17.01.028","DOIUrl":"https://doi.org/10.33271/mining17.01.028","url":null,"abstract":"Purpose. The research purpose is to develop a mathematical model of a pressureless flow in a channel with the occurrence in some areas of overflow layer through the wall. Using this model, it is possible to calculate the overflow layer height and length, as well as the change in flow rate in the channel due to the withdrawal of part of the fluid as a result of the overflow. Methods. The research uses a comprehensive multi-stage analytical approach. Firstly, in order to develop a mathematical model for a pressureless flow in the channel with the occurrence in some areas of overflow layer through the wall, this research analytically determines the dependence of the flow rate through the channel wall based on formulas for calculating the weir discharge coefficient. At the second stage, a mathematical model of a hydraulic mixture pressureless flow in a rectangular channel with an overflow through the wall is developed to determine the parameters and flow regimes of the stream. Findings. The dependences of the dimensionless height of the overflow through the channel wall and the effective critical flow depth on the dimensionless current channel length have been obtained for various values of the acting force parameters and the process parameter of the fluid overflow through the channel wall. This made it possible to study the dynamics of changes in these values along the channel for various values of the specified parameters, and to assess the degree of influence of the relevant factors on the characteristics of the pressureless flow along the channel and the process of fluid overflow through wall. Originality. For the first time, the model of the pressureless flow in the channel is generalized for the case of occurrence in some areas of overflow layer through the wall, when the length and height of the overflow layer are not determined by a hole in the side surface, but are controlled by a decrease in the corresponding flow rate. For the first time, this model makes it possible to calculate the height and length of the overflow layer and the change in the flow rate in the channel due to the withdrawal of part of the fluid as a result of the overflow in cases of overflowing condition of the channel with the stream under unstable and non-calculated flow regimes. Practical implications. The mathematical model and the calculation results can be used to ensure the environmental safety of the logistics systems of mining enterprises, as well as to assess the volume of the environmental pollution in case of overflowing through the wall of the channels of pressureless hydraulic transportation of waste from mineral processing and metallurgical plants.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49666226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-30DOI: 10.33271/mining17.01.074
N. Zholmagambetov, E. Khalikova, V. Demin, Anna Balabas, Rabbel Abdrashev, Saule Suiintayeva
Purpose. The research purpose is to determine the instability zones in the host rocks and the dynamics of propagation of active fracturing zones to ensure the stability of the rock mass surrounding the mine workings. Methods. The research uses a set of analytical and experimental studies to determine the dynamics of the deformation process development in the coal-rock mass surrounding the mine workings. Mathematical modeling of the stress-strain state of the rock mass surrounding the active extraction workings is performed using the numerical method of finite elements in modern AN-SYS, Mergel and KMS-III software products. Findings. The influence has been studied of the mine working section shape and the coal seam dip angle on the value of the maximum stresses that arise in the rock mass when the mine working is fastened with the roof-bolt support. The instability zones in the host rocks and the dynamics of propagation of active fracturing zones have been determined both ahead of the front of the conducted mine working and on its sides for rocks of different strength. Originality. For the conditions of the Karaganda coal basin, the dependence of a change in the development of conventional inelastic deformation zones (CIDZ) on the host rock strength has been revealed. The influence of the coal seam dip angle on the dynamics of stratifications around preparatory working has also been substantiated. In addition, new data have been obtained on the influence of the roof rock strength on the stratification of the rock mass surrounding the mine working. Practical implications. By determining instability zones in the host rocks and the dynamics of propagation of active fracturing zones, it is possible to control geomechanical processes in the border rock mass of a mine working and influence it in order to prevent the occurrence of negative rock pressure manifestations. The data obtained are the basis for the development of recommendations on the use of roof-bolting technology for fastening extraction workings to ensure their stability and reduce the cost of their operation.
{"title":"Ensuring a safe geomechanical state of the rock mass surrounding the mine workings in the Karaganda coal basin, Kazakhstan","authors":"N. Zholmagambetov, E. Khalikova, V. Demin, Anna Balabas, Rabbel Abdrashev, Saule Suiintayeva","doi":"10.33271/mining17.01.074","DOIUrl":"https://doi.org/10.33271/mining17.01.074","url":null,"abstract":"Purpose. The research purpose is to determine the instability zones in the host rocks and the dynamics of propagation of active fracturing zones to ensure the stability of the rock mass surrounding the mine workings. Methods. The research uses a set of analytical and experimental studies to determine the dynamics of the deformation process development in the coal-rock mass surrounding the mine workings. Mathematical modeling of the stress-strain state of the rock mass surrounding the active extraction workings is performed using the numerical method of finite elements in modern AN-SYS, Mergel and KMS-III software products. Findings. The influence has been studied of the mine working section shape and the coal seam dip angle on the value of the maximum stresses that arise in the rock mass when the mine working is fastened with the roof-bolt support. The instability zones in the host rocks and the dynamics of propagation of active fracturing zones have been determined both ahead of the front of the conducted mine working and on its sides for rocks of different strength. Originality. For the conditions of the Karaganda coal basin, the dependence of a change in the development of conventional inelastic deformation zones (CIDZ) on the host rock strength has been revealed. The influence of the coal seam dip angle on the dynamics of stratifications around preparatory working has also been substantiated. In addition, new data have been obtained on the influence of the roof rock strength on the stratification of the rock mass surrounding the mine working. Practical implications. By determining instability zones in the host rocks and the dynamics of propagation of active fracturing zones, it is possible to control geomechanical processes in the border rock mass of a mine working and influence it in order to prevent the occurrence of negative rock pressure manifestations. The data obtained are the basis for the development of recommendations on the use of roof-bolting technology for fastening extraction workings to ensure their stability and reduce the cost of their operation.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48334768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}