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Number of results: 62
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Abstract

To produce the lime required for the Bayer process, two parallel flow regenerative shaft kilns (PFR) were used in the Iran Alumina plant located in Jajarm, North Khorasan Province, Iran. In this study, the calcination conditions of limestone were modelled in a laboratory furnace by considering three factors of limestone size, temperature and calcination time using the Box-Behnken method. The calcination model of limestone was obtained using a quadratic equation. Due to the importance of limestone dust in the performance of industrial kilns, conditions of calcification and its reactivity with water were examined at three temperature ranges of 800, 1000, and 1200°C, by two methods of titration and standard ASTM C110. The results indicated a decrease in reactivity of lime relative to the increased temperature of calcination and the lack of forming the burnt lime particles that stick together (blocking). Finally, the ratio of input limestone (kg) to fuel (m3) was reduced from 16.4 to 15.3 to increase the average temperature of the burning zone to 1000°C. Also, excess air was reduced from 40 to 20%. In this condition, the lime quality was increased by about 6% in the kilns.
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Authors and Affiliations

Hosseinali Mirzaei
1
ORCID: ORCID
Mohammad Noaparast
1
ORCID: ORCID
Hadi Abdollahi
1
ORCID: ORCID

  1. School of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran
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Abstract

Industrial size pipe loop tests were conducted to determine the effect of paste mass concentration, cement content, conveying pipe diameter and conveying volumetric flow rate, on the pipeline pressure loss of paste slurry. The tests were conducted to determine the pressure losses in the backfill system at a Copper Mines major ore body. Results show that the pressure loss of paste slurry increases with the increase in mass concentration, and when the mass concentration exceeds 70%, the pressure loss will increase sharply and would be an exponential function of paste mass concentration; as the cement content increases, the pressure loss would decrease at first and then increase with the maximum pressure loss at 11% cement content; the pressure loss increases with the increase in conveying the volumetric flow rate accordingly, while the growth rate of pressure loss will increase after the volumetric flow rate exceeds 50 m 3/h; the pressure loss of paste slurry decreases sharply with the increase in pipe diameter, i.e., the larger pipe diameter, the smaller pressure loss; lastly, the paste conveying parameters were determined as mass concentration of lower than 70% (pressure loss: 2.55 MPa/km), cement content of 5% to 11%, inside diameter of conveying pipe of 150 mm and the maximum allowable pipeline pressure of 6 MPa.
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Authors and Affiliations

Wei Sun
1
ORCID: ORCID
Minggui Jiang
1
ORCID: ORCID
Kai Fan
1
ORCID: ORCID
Zeng Liu
1
ORCID: ORCID

  1. Kunming University of Science and Technology, Faculty of Land Resources Engineering, Yunnan Key Laboratory of Sino-German Blue Mining and Utilization of Special Underground Space, China
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Abstract

The Euler multiphase flow and population equilibrium model were used to simulate the three-phase flow field in the bubble expansion stage of the outlet curved pipe section. The influence of the ratio of the bending diameter and the volume fraction of the gas phase on the pressure loss is revealed, and the safety range of the optimum bending diameter ratio and the volume fraction of the outlet gas phase is determined. The results show that the three-phase flow in the tube is more uniformly distributed in the vertical stage, and when the pipe is curved, the liquid-phase close to the pipe wall gathers along the pipe flank to the outside of the pipe, the solid phase is transferred along the pipe flank to the inside of the pipe, and the gas phase shrinks along the pipe flank to the inner centre. The maximum speed of each phase of the three-phase flow in the elbow is at the wall of the tube from 45° to 60° inside the elbow, and the distribution law along the axial direction of the pipe is about the same as the distribution law of volume fraction. The pressure loss of the elbow decreases with the increase of the bend diameter ratio, when the bend diameter ratio increases to 6, the pressure loss of the pipe decreases sharply, and the pressure loss decreases slowly with the increase of the bend diameter ratio. When the gas phase volume score in the elbow reaches 70%, there will be an obvious wall separation phenomenon, to keep the system in a stable working state and prevent blowout, the gas phase volume score should be controlled within 60%.
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Authors and Affiliations

Wei Chen
1 2 3
ORCID: ORCID
Hai-liang Xu
2 3
ORCID: ORCID
Bo Wu
2 3
ORCID: ORCID
Fang-qiong Yang
2 3
ORCID: ORCID

  1. Hunan University of Humanities, Department of Energy and Electrical Engineering, Science and Technology, Loudi, Hunan 417000, China
  2. Central South University, School of Mechanical and Electrical Engineering, Changsha, Hunan 410083, China
  3. State Key Laboratory of High Performance Complex Manufacturing, Changsha, Hunan 410083, China
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Abstract

The dynamic characteristics of the hydraulic leg are essential for determining the safe working range of roof supports operating in seams threatened by rock mass tremors. The systematic increase in the support of the hydraulic legs due to deteriorating geological-mining conditions has increased their diameters, which currently exceed 0.32 m for the 1st hydraulic stage. Evaluation of the dynamic properties of the roof support and the hydraulic legs are carried out by the Central Mining Institute through calculation methods as an implementation of the Regulation of the Minister of Energy on occupational safety and health. However, the issue of validating the calculations concerning natural scale studies still needs to be addressed. There are significant limitations in this area due to the technical and metrological capabilities of the testing stations. This paper presents an attempt to evaluate bench testing of a hydraulic leg with 0.32 m of the 1st hydraulic stage diameter for the validation of computational and test methods. Results of previous studies affecting the evaluation of the research methods used are also cited. According to the authors, the optimal and economically justifiable direction is to undertake model tests using numerical analyses and to validate these results, based on the study of models of hydraulic legs that are in use at a reduced scale. The construction of testing stations to ensure adequate dynamic loading for the support of the largest diameter hydraulic legs is currently not economically viable. The problem presented, however, is important given the constantly deteriorating geological-mining conditions and the associated threat of rock mass tremors.
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Authors and Affiliations

Kazimierz Stoiński
1
ORCID: ORCID
Marek Płonka
1
ORCID: ORCID
Janina Świątek
1
ORCID: ORCID

  1. Central Mining Institute (GIG ), 1 Gwarków Sq., 40-166 Katowice, Poland
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Abstract

In this study, an old rotational landslide that has reactivated in the NW sector of an open-pit mine operated within the gneiss rock unit was evaluated for geological and hydrogeological properties. The pit slopes were susceptible to mass movement when there were variations in water inflows. Considering this fact, a conceptual numerical model concerning geostructural features, rainfall infiltration, and varying hydrological conditions was constructed. Initially, finite element (FE) groundwater seepage analyses were performed to evaluate the effect of water flow on stability in the dry and rainy seasons. The rainy season was simulated by vertical infiltration. Since the dewatering measures are of importance in open pit slope instability mitigation, pumping wells were designed to control water flow through the disturbed zone to improve the stability of the sector that can be triggered again with changing environmental conditions. The performance and organization of the pumping wells were also simulated in the FE model. This FE model was part of a dewatering plan. From this, the effect of the pumping rate from the wells on the stability of the sector was revealed. It was also found that there should be an increase in the pumping rate in the rainy season.
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Authors and Affiliations

Tümay Kadakci Koca
1
ORCID: ORCID

  1. Muğla Sıtkı Koçman University, Turkey
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Abstract

W strap is a crucial surface support component for underground coal mine roadways. In this study, the failure characteristics of the W strap in the field are discussed, and the loading characteristics of the strap and the faceplate are numerically and experimentally analysed. Afterwards, a loading apparatus capable of reappearing the loading environment of the strap in the field is fabricated. This loading device, combined support systems consisting of a bolt, faceplate and strap is tested under different simulated strata conditions. Failure patterns of the strap are evaluated by the 3D scanning method, and proper selection of a faceplate is explored. Results indicate that a domed faceplate can achieve a favourable supporting effect on strata, and thus it is favoured compared with a square domed faceplate. In addition, rock cavity and rock integrity beneath the strap are essential factors determining the servicing life of the overall supporting system.
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Authors and Affiliations

Xiaowei Feng
1
ORCID: ORCID
Fei Xue
2
ORCID: ORCID
Xiaotian Feng
3
ORCID: ORCID
Tongyang Zhao
2
ORCID: ORCID

  1. China University of Mining and Technology, China
  2. Shaoxing University, Key Laboratory of Rock Mechanics and Geohazards of Zhejiang Province, China
  3. Xi’an University of Architecture and Technology, Politecnico di Milano, China
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Abstract

The rheological behaviour of cemented paste backfill (CPB) has an important influence on the stability of its transportation in pipelines. In the present study, the time-dependent rheological behaviour of CPB was investigated to elucidate the effects of time and solid content. Experimental results showed that when CPB is subjected to a constant shear rate, the shear stress gradually decreases with time before finally stabilis ing. When the solid content was 60%~62%, a liquid network structure was the main factor that influenced the thixotropy of CPB, and the solid content had less influence. When the solid content was 64%~66%, a floc network structure was the main factor that influenced the thixotropy of CPB, and the solid content had a more significant influence on the thixotropy than the shear rate. The initial structural stability of CPB increased with the solid content, and this relationship can be described by a power function. Based on the experimental results, a calculation model of pipeline resistance considering thixotropy was proposed. The model was validated by using industrial experimental data. The current study can serve as a design reference for CPB pipeline transportation.
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Authors and Affiliations

Yingjie Chang
1
ORCID: ORCID
Youzhi Zhang
1
ORCID: ORCID
Deqing Gan
1
ORCID: ORCID
Xinyi Wang
1
ORCID: ORCID
Shuangcheng Du
1
ORCID: ORCID

  1. North China University of Science and Technology, College of Mining Engineering, China
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Abstract

Contemporary mine exploitation requires information about the deposit itself and the impact of mining activities on the surrounding surface areas. In the past, this task was performed using classical seismic and geodetic measurements. Nowadays, the use of new technologies enables the determination of the necessary parameters in global coordinate systems. For this purpose, the relevant services create systems that integrate various methods of determining interesting quantities, e.g., seismometers / GNSS / PSInSAR. These systems allow detecting both terrain deformations and seismic events that occur as a result of exploitation. Additionally, they enable determining the quantity parameters that characterise and influence these events. However, such systems are expensive and cannot be set up for all existing mines. Therefore, other solutions are being sought that will also allow for similar research. In this article, the authors examined the possibilities of using the existing GNSS infrastructure to detect seismic events. For this purpose, an algorithm of automatic discontinuity detection in time series “Switching Edge Detector” was used. The reference data were the results of GNSS measurements from the integrated system (seismic / GNSS / PSInSAR) installed on the LGCB (Legnica-Głogów Copper Belt) area. The GNSS data from 2020 was examined, for which the integrated system registered seven seismic events. The switching Edge Detector algorithm proved to be an efficient tool in seismic event detection.
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Authors and Affiliations

Dariusz Tomaszewski
1
ORCID: ORCID
Jacek Rapiński
1
ORCID: ORCID
Lech Stolecki
2
ORCID: ORCID
Michał Śmieja
3
ORCID: ORCID

  1. University of Warmia and Mazury in Olsztyn, Faculty of Geoengineering, Institute of Geodesy and Civil Engineering, 2 Oczapowskiego Str., Olsztyn, 10-900, Poland
  2. KGHM CUPRUM Sp. z.o.o. Research and Development Centre, gen. W. Sikorskiego Street 2-8, Wrocław, 53-659, Poland
  3. University of Warmia and Mazury in Olsztyn, Faculty of Technical Sciences, Chair of Mechatronics, 2 Oczapowskiego Str., Olsztyn, 10-900, Poland
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Abstract

The stability of longwall mining is one of the most important and the most difficult aspects of underground coal mining. The loss of longwall stability can threaten lives, disrupt the continuity of the mining operations, and it requires significant materials and labour costs associated with replacing the damages. In fact, longwall mining stability is affected by many factors combined. Each case of longwall mining has its own unique and complex geological and mining conditions. Therefore, any case study of longwall stability requires an individual analysis. In Poland, longwall mining has been applied in underground coal mining for years. The stability of the longwall working is often examined using an empirical method. A regular longwall mining panel (F3) operation was designed and conducted at the Borynia-Zofiówka-Jastrzębie (BZJ) coal mine. During its advancement, roof failures were observed, causing a stoppage. This paper aims to identify and determine the mechanisms of these failures that occurred in the F3 longwall. A numerical model was performed using the finite difference method - code FLAC2D, representing the exact geological and mining conditions of the F3 longwall working. Major factors that influenced the stability of the F3 longwall were taken into account. Based on the obtained results from numerical analysis and the in-situ observations, the stability of the F3 longwall was discussed and evaluated. Consequently, recommended practical actions regarding roof control were put forward for continued operation in the F3 longwall panel.
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Authors and Affiliations

Phu Minh Vuong Nguyen
1
ORCID: ORCID
Sylwester Rajwa
1
ORCID: ORCID
Marek Płonka
1
ORCID: ORCID
Waldemar Stachura
2

  1. Central Mining Institute (GIG), 1 Gwarków Sq., 40-166 Katowice, Poland
  2. Jastrzębska Spółka Węglowa SA, Poland
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Abstract

The article describes the behaviour of the flysch rock massif (Carpathian flysch) during the drilling of three tunnels in the preliminary lining. These tunnels were excavated in: “Naprawa”, “Laliki”, and “Świnna Poręba”. The distance between these tunnels in a straight line was 50 km to 90 km. The results of the displacement of the contours of these tunnels and their convergence were analysed in detail. These values were compared with the indices used to assess the behaviour of the rock mass in the tunnel environment (Zasławski index and Hoek index) and the adopted limit values of displacements and deformations. On this basis, a critical analysis of the selection of initial supports in the completed tunnels was made, showing errors at the design stage.
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Authors and Affiliations

Antoni Tajduś
1
ORCID: ORCID
Krzysztof Tajduś
2
ORCID: ORCID

  1. Faculty of Civil Engineering and Resource Management, AGH University of Science and Technology, Mickiewicza 30 av., 30-059 Cracow, Poland
  2. Strata Mechanics Research Institute, Polish Academy of Science, 27 Reymonta Str., 30-059 Krakow, Poland
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Abstract

The ecological environment is significantly vulnerable to coal-mining activities in western China due to the cold and arid climate. The evaluation of land reclamation is therefore a key process that has to be known for the sustainable use of coal resources. A Bayes discriminant analysis method to evaluate the suitability level of land reclamation for coal mine lands in cold and arid regions of western China is presented. Ten factors influencing the suitability of land reclamation were selected as discriminant indexes in the suitability analysis. The data of eighty-four land reclamation units from sixteen coal-mining areas was used as training samples to develop a discriminant analysis model to evaluate the suitability level of land reclamation. The results show that the discriminant analysis model has high precision and the misdiscriminant ratio is 0.02 in the resubstitution process.The suitability levels of land reclamation for eleven sites in two coal mine lands were evaluated by using the model and the evaluation results are identical with that of the practical situation. Our method and findings are significant for decision makers in similar regions who want to prepare for possible strategies for land reclamation in the future.
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Authors and Affiliations

Ruihua Hao
1
ORCID: ORCID
Zizhao Zhang
1 2
Xiaoli Guo
3
Xuebang Huang
1
Zezhou Guo
1
Tianchao Liu
4

  1. School of Geological and Mining Engineering, Xinjiang University, Urumqi, Xinjiang, China
  2. State Key Laboratory for Geomechanics and Deep Underground Engineering, Xinjiang University, Urumqi, Xinjiang, China
  3. Xinjiang Intelligent Check for Security Environmental Protection Technology Co., Ltd, Urumqi, Xinjiang, China
  4. The First Regional Geological Survey Brigade, Xinjiang Bureau of Geo-Exploration & Mineral Development, 466 North Tianjin road, Urumqi, Xinjiang, China
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Abstract

This paper presents an experimental study on the leaching of heavy metals, toxic chemicals and persistent organic pollutants (POPs) – PAH, PCB and HCB – from soil dredged from the coastal area of Västernorrland in northern Sweden. The soil was stabilized with cement/slag. Samples were subjected to modified surface leaching and shake tests using technical standards of the Swedish Geotechnical Institute (SGI). The experiments were performed using different blends of binding agents (30/70, 50/50, 70/30) and binder quantities (120 and 150 kg/m3) to analyze their effects on leaching. Soil properties, tools, and workflow are described. Binders included Portland cement and ground granulated blast furnace slag (GGBFS). Samples were tested to evaluate the min/max contents of pollutants (μg/l) for heavy metals (As, Ba, Pb, Cd, Co, Cu, Cr, Hg, Mn, Mo, Ni, S, V, Zn) and the hydrocarbon fraction index in the excess water. The leaching of heavy metals and POPs was assessed in sediments after the addition of the binder. The comparison was made against the two mixes (cement/slag in 30/70% and high/low binder with low/high water ratio). The results showed that 70% slag decreases the leaching of heavy metals and POPs. The equilibrium concentrations of DOC and heavy metals at L/S 10 (μg/l) were measured during the shake experiments to compare their levels in the groundwater that was used as a leachate. The leached content was assessed at L/S 10 in the upscaling experiments using four samples for PAH, PCB and various fractions of hydrocarbons: C10–C40, C10–C12, C12–C16 and C35–C40. The shake test showed a decrease in the leaching of heavy metals and POP substances from the soil subjected to stabilization by a higher amount of slag added as a binder. A binder blend with 30% cement and 70% of GGBFS showed the best performance.
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Authors and Affiliations

Per Lindh
1 2
ORCID: ORCID
Polina Lemenkova
3
ORCID: ORCID

  1. Swedish Transport Administration, Malmö, Sweden
  2. Lund University, Lund, Sweden
  3. Université Libre de Bruxelles, Brussels, Belgium
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Abstract

The aim of this study was to evaluate foundry waste used for various applications in terms of heavy metals quantity of fractions of their binding. The novelty of these studies is the use of speciation procedures to assess the fraction of heavy metals in foundry waste. The two most popular speciation procedures, the Tessier method and the SM&T, and also the TCLP single extraction procedure were used to evaluate the use of foundry waste in agritechnique, road engineering and construction in this research. Additionally, local soils were analyzed and compared to landfill foundry waste (LFW). It was found that LFW may have a negative impact on the natural environment when used for agrotechnological applications due to the increased concentration of mobile and bioavailable fractions (mean 9–18%) of metals. Foundry dusts were characterized by a low percentage of mobile and bioavailable (mean 2–6%) forms, although this does not include electric arc fournance dust (EAFD) (mean 17%). The metal content in TCLP extracts was low in all foundry waste samples and allowed the use of the analyzed wastes in construction and road construction. The usefulness of both speciation procedures for the assessment of the leaching of heavy metal forms from foundry waste was confirmed. However, the SM&T procedure was more effective in leaching mobile and bioavailable forms of heavy metals in foundry waste and soil samples.
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Authors and Affiliations

Marta Bożym
1
ORCID: ORCID

  1. Opole University of Technology, Opole, Poland
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Abstract

The subject of this article is the problem of payment gridlocks and their significance for the enterprise sector and the risks they cause. The authors’ attention is focused here on presenting the essence of payment gridlocks, their consequences, as well as the causes on the sides of both the debtor and the creditor. In the empirical part of the article, the authors focused on assessing the problem of payment backlogs in selected mining and energy-production companies in Poland. A study on selected companies from this industry was conducted, the purpose of which was to show the scale of delayed payments with the particular identification of those that are payment backlogs (i.e. a delay of at least 60 days). Five major companies from the energy industry in Poland were selected for the study, representing both the mining and energy production sectors. These companies are Polska Grupa Górnicza SA, Jastrzębska Spółka Węglowa SA, ENEA SA, Energa SA and TAURON Polska Energia SA According to the available data, payment terms in this sector are the longest in the European Union compared to other sectors of the economy. In Poland, the situation is no different in this respect. This is especially visible in the mining industry, which is perceived as very risky when it comes to timely payments. Undoubtedly, reducing payment gridlocks in this industry is a difficult task, which results from its specificity and the number of problems it is struggling with, which have been additionally reinforced by the Covid-19 pandemic.
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Authors and Affiliations

Łukasz Szewczyk
1
ORCID: ORCID
Grażyna Szustak
1
ORCID: ORCID

  1. University of Economics in Katowice, Poland
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Abstract

The environmental problems caused by the development and utilization of mineral resources have become important factors affecting ecological security. Guizhou is a Chinese province with relatively developed paleoweathered sedimentary bauxite deposits, abundant resource reserves, and a long history of mining. And, the demand for bauxite in Guizhou is expected to continue to grow. However, long-term or unreasonable resource development has produced a series of prominent environmental problems, such as the occupation and destruction of land resources and heavy metal pollution in soil and water bodies. Based on the existing research results in China and abroad, this paper analyzes the current situation, distribution characteristics, and development and utilization of bauxite resources in Guizhou to explain the corresponding environmental impacts. The results show that because of the many types and high concentrations of associated elements in bauxite and the high alkalinity, heavy metal components, and radioactive elements in red mud, the development and utilization of bauxite resources are associated with higher environmental risk. And more impact of bauxite mining on regional biodiversity, soil, air, surface water, and groundwater need to be evaluated. This paper also proposes coping strategies or countermeasures of environmental governance and control to achieve the green, sustainable and high-quality development of bauxite-related industries for meeting future environmental requirements.
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Authors and Affiliations

Xiaofu Chen
1 2
Xuexian Li
3
Pan Wu
1 3
ORCID: ORCID
Xuefang Zha
3
Yabin Liu
2
Tao Wei
2
ORCID: ORCID
Wenrui Ran
2

  1. College of Resources and Environmental Engineering, Guizhou University, China
  2. Natural Resources Survey and Planning Institute, Guiyang, China
  3. Key Laboratory of Karst Georesources and Environment, Ministry of Education, Guiyang, China
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Abstract

This paper presents the results of analyses of structure, volume and trends of demand for selected major critical raw materials (CRMs) suitable for the EU’s photovoltaic industry (PV). In order to achieve the EU’s goals in terms of the reduction of greenhouse gas emission and climate neutrality by 2050, the deployment of energy from renewable sources is of key importance. As a result, a substantial development of wind and solar technologies is expected. It is forecasted that increasing the production of PV panels will cause a significant growth in the demand for raw materials, including CRMs. Among these, silicon metal, gallium, germanium and indium were selected for detailed analyses while boron and phosphorus were excluded owing to small quantities being utilized in the PV sector. The estimated volume of the apparent consumption in the EU does not usually exceed 0.1 million tonnes for high purity silicon metal, a hundred tonnes for gallium and indium and several dozen tonnes for germanium. The major net-importers of analyzed CRMs were Germany, France, Spain, Czech Republic, the Netherlands, Slovakia and Italy. The largest quantities of these metals have been utilized by Germany, France, Belgium, Slovakia and Italy. The PV applications constitute a marginal share in the total volume of analyzed metal total end-uses in the EU (10% for silicon metal, 5% for gallium, 13% for germanium and 9% for indium). As a result, there is a number of applications that compete for the same raw materials, particularly including the production of electronic equipment. The volume of the future demand for individual CRMs in PV sector will be strictly related to trends in the development of PV-panel production with crystalline silicon technology currently strongly dominating the global market.
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Authors and Affiliations

Katarzyna Guzik
1
ORCID: ORCID
Anna Burkowicz
1
ORCID: ORCID
Jarosław Szlugaj
1
ORCID: ORCID

  1. Mineral and Energy Economy Research Institute, Polish Academy of Sciences, Kraków, Poland
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Abstract

The mean-reversion model is introduced into the study of mineral product price prediction. The gold price data from January 2018 to December 2021 are selected, and a mean-reverting stochastic process simulation of the gold price was carried out using Monte Carlo simulation (MCS) method. By comparing the statistical results and trend curves of the mean-reversion (MR) model, geometric Brownian motion (GBM) model, time series model and actual price, it is proved that the mean-reversion process is valid in describing the price fluctuation of mineral product. At the same time, by comparing with the traditional prediction methods, the mean-reversion model can quantitatively assess the uncertainty of the predicted price through a set of equal probability stochastic simulation results, so as to provide data support and decision-making basis for the risk analysis of future economy.
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Authors and Affiliations

Shuwei Huang
1 2 3
ORCID: ORCID
Zhaoyang Ma
1
Feng Jin
1
ORCID: ORCID
Yuansheng Zhang
1

  1. BGRIMM Technology Group, China
  2. Beijing Key Laboratory of Nonferrous Intelligent Mining Technology, China
  3. BGRIMM Intelligent Technology Co. Ltd, China
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Abstract

The demand for energy on a global scale increases day by day. Unlike renewable energy sources, fossil fuels have limited reserves and meet most of the world’s energy needs despite their adverse environmental effects. This study presents a new forecast strategy, including an optimization-based S-curve approach for coal consumption in Turkey. For this approach, Genetic Algorithm (GA) and Particle Swarm Optimization (PSO), Grey Wolf Optimization (GWO), and Whale Optimization Algorithm (WOA) are among the meta-heuristic optimization techniques used to determine the optimum parameters of the S-curve. In addition, these algorithms and Artificial Neural Network (ANN) have also been used to estimate coal consumption. In evaluating coal consumption with ANN, energy and economic parameters such as installed capacity, gross generation, net electric consumption, import, export, and population energy are used for input parameters. In ANN modeling, the Feed Forward Multilayer Perceptron Network structure was used, and Levenberg-Marquardt Back Propagation has used to perform network training. S-curves have been calculated using optimization, and their performance in predicting coal consumption has been evaluated statistically. The findings reveal that the optimization-based S-curve approach gives higher accuracy than ANN in solving the presented problem. The statistical results calculated by the GWO have higher accuracy than the PSO, WOA, and GA with R 2 = 0.9881, RE = 0.011, RMSE = 1.079, MAE = 1.3584, and STD = 1.5187. The novelty of this study, the presented methodology does not need more input parameters for analysis. Therefore, it can be easily used with high accuracy to estimate coal consumption within other countries with an increasing trend in coal consumption, such as Turkey.
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Authors and Affiliations

Mustafa Seker
1
ORCID: ORCID
Neslihan Unal Kartal
2
Selin Karadirek
3
Cevdet Bertan Gulludag
3

  1. Sivas Cumhuriyet University, Turkey
  2. Burdur Mehmet Akif Ersoy University, Turkey
  3. Akdeniz University, Antalya, Turkey
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Abstract

In order to improve the utilization rate of coal resources, it is necessary to classify coal and gangue, but the classification of coal is particularly important. Nevertheless, the current coal and gangue sorting technology mainly focus on the identification of coal and gangue, and no in-depth research has been carried out on the identification of coal species. Accordingly, in order to preliminary screen coal types, this paper proposed a method to predict the coal metamorphic degree while identifying coal and gangue based on Energy Dispersive X-Ray Diffraction (EDXRD) principle with 1/3 coking coal, gas coal, and gangue from Huainan mine, China as the research object. Differences in the phase composition of 1/3 coking coal, gas coal, and gangue were analyzed by combining the EDXRD patterns with the Angle Dispersive X-Ray Diffraction (ADXRD) patterns. The calculation method for characterizing the metamorphism degree of coal by EDXRD patterns was investigated, and then a PSO-SVM model for the classification of coal and gangue and the prediction of coal metamorphism degree was developed. Based on the results, it is shown that by embedding the calculation method of coal metamorphism degree into the coal and gangue identification model, the PSO-SVM model can identify coal and gangue and also output the metamorphism degree of coal, which in turn achieves the purpose of preliminary screening of coal types. As such, the method provides a new way of thinking and theoretical reference for coal and gangue identification.
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Authors and Affiliations

Yanqiu Zhao
1
ORCID: ORCID
Shuang Wang
1
Yongcun Guo
1
Gang Cheng
1
Lei He
1
Wenshan Wang
1

  1. School of Mechanical Engineering, Anhui University of Science and Technology, China
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Abstract

This paper presents the results of an analysis of selected seismic profiles (reflection and refraction data) from the Radom-Lublin area aimed at obtaining a better understanding of geological structure and the identification of hydrocarbon deposits. To accurately reproduce the seismic reflection covering the sub-Permian formations, seismic cross sections were interpreted based on effective reflection coefficients (ERC). In interpreting the results, reference was made to the results of studies of the area using other geophysical methods.
The results of these studies made it possible to obtain new information on the geology and structure of the Paleozoic complex of the Radom-Lublin area and its relationships with the basement tectonics. The structural arrangement of Carboniferous and Devonian formations as well as older Silurian, Ordovician, and Cambrian series were recognized. Selected significant tectonic and lithological discontinuities and the nature and directions of their course were characterized. Special attention was given to regional tectonic zones: the Skrzynno Fault, the Ursynów-Kazimierz fault zone and the Kock zone. The use of ERC methodology made it possible to define the boundaries of lithostratigraphic units in Carboniferous, Devonian, and older formations. The obtained results can be used to assess hydrocarbon accumulation in the area under consideration.
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Authors and Affiliations

Lidia Dziewińska
1
ORCID: ORCID
Radosław Tarkowski
1
ORCID: ORCID

  1. Mineral and Energy Economy Research Institute, Polish Academy of Sciences, Kraków, Poland
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Abstract

The article deals with issues related to the application of statistical methods used in the valuation process. The proposed algorithm for real estate valuation can be used in the statistical market analysis method in the process of mass appraisal. The algorithm uses a multiple linear regression model. Legal considerations indicate the need for such an algorithm for the determination of the value of representative properties. Due to the large size of the database of comparables, the proposed algorithm can be used only to appraise typical properties. A good statistical model is parsimonious, that is, it uses as few mathematical concepts as possible in a given situation. A model should extract what is systematic in the results observed, allowing for the presence of purely random deviations. The article discusses the basic principles of building a good statistical model. Attention is drawn to the number of market attributes that are entered into the model and the range of their values. As few explanatory variables as possible should be entered into the model to explain the phenomenon under study. Explanatory variables are only those characteristics of the property that differentiate prices in a given market defined and adopted by the appraiser as the basis for valuation. The article highlights the importance of taking into account market changes during the period under study.
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Authors and Affiliations

Agnieszka Bitner
1
ORCID: ORCID
Małgorzata Frosik
1
ORCID: ORCID

  1. University of Agriculture in Krakow, Krakow, Poland
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Abstract

The object of the study is the processing of space images on the territory of the Carpathian territory in the Lviv region, obtained from the Landsat-8 satellite. The work aims to determine the area of deforestation in the Carpathian territory of the Lviv region from different time-space images obtained from the Landsat-8 satellite. Methods of cartography, photogrammetry, aerospace remote sensing of the Earth and GIS technology were used in the experimental research. The work was performed in Erdas Imagine software using the unsupervised image classification module and the DeltaCue difference detection module. The results of the work are classified as three images of Landsat-8 on the territory of the Carpathian territory in the Lviv region. The areas of forest cover for each of them for the period of 2016-2018 have been determined. During the three years, the area of forests has decreased by 14 hectares. Our proposed workflow includes six stages: analysis of input data, band composition of space images on the research territory, implementation of unsupervised classification in Erdas Imagine software and selection of forest class and determination of implementing this workflow, the vector layers of the forest cover of the Carpathians in the Lviv region for 2016, 2017, 2018 were obtained, and on their basis, the corresponding areas were calculated and compared.
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Authors and Affiliations

Borys Chetverikov
1
ORCID: ORCID
Ihor Trevoho
1
ORCID: ORCID
Lubov Babiy
1 2
ORCID: ORCID
Mariia Malanchuk
1
ORCID: ORCID

  1. Lviv Polytechnic National University, Lviv, Ukraine
  2. Kryvyi Rih National University, Kryvyi Rih, Ukraine

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