Copper Mine
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Metals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1903
Author(s):  
Jincheng Xie ◽  
Dengpan Qiao ◽  
Runsheng Han ◽  
Jun Wang

In order to reasonably and accurately acquire the settlement interface and velocity of tailings, an identification model of tailing settlement velocity, based on gray images of the settlement process and unsupervised learning, is constructed. Unsupervised learning is used to classify stabilized tailing mortar, and the gray value range of overflow water is determined. Through the identification of overflow water in the settlement process, the interface can be determined, and the settlement velocity of tailings can be calculated. Taking the tailings from a copper mine as an example, the identification of tailings settling velocity was determined. The results show that the identification model of tailing settlement speed based on unsupervised learning can identify the settlement interface, which cannot be manually determined in the initial stage of settlement, effectively avoiding the subjectivity and randomness of manual identification, and provide a more scientific and accurate judgment. For interfaces that can be manually recognized, the model has high recognition accuracy, has a rapid and efficient recognition process, and the relative error can be controlled within 3%. It can be used as a new technology for measuring the settling velocity of tailings.


Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Xianglong Li ◽  
Qiang Li ◽  
Jianguo Wang ◽  
Zichen Wang ◽  
Hao Wang ◽  
...  

In order to optimize the arrangement of cutting holes in tunnel blast in Dahongshan Copper Mine, theoretical analysis and numerical simulation were combined to preliminarily determine the diameter of the hollow hole and the distance between the charge hole and the hollow hole during cut blast, which was verified through the field blast test. The research results show that with the increase of the hole diameter, the peak compressive stress of rock surrounding the empty hole gradually decreases, and the peak tensile stress gradually increases, which is consistent with the calculation results; when the hole diameter is 10 cm, the two first blast holes are arranged horizontally and 30 cm from the empty hole, two second blast holes are arranged vertically and 40 cm away from the empty hole, and the four third blast holes are arranged at a horizontal distance of 45 cm and a vertical distance of 45 cm from the empty hole; the contour area in numerical simulation is the maximum. The difference in contour area, contour width, and contour and contour height between the measured value and the simulation result is 5.3%, 3.3%, and 3.4%, respectively, indicating that the combination of theoretical calculation and numerical simulation is suitable for prediction of cavity section after blast in tunnel excavation.


2021 ◽  
Author(s):  
Shokoofeh Hajihashemi ◽  
Shakiba Rajabpoor ◽  
Marian Brestic

Abstract Mining activity is one main source of heavy metal pollution. In this study, Al, Ba, Be, Ca, Cd, Co, Ce, Cr, Cu, Fe, Ga, Gd, K, La, Li, Mg, Mn, Na, Nb, Nd, Ni, P, Pb, S, Sc, Si, Sr, Ti, V, Y, Zn and Zr were measured by ICP-OES analyzing of the soils taken in the Dehmadan mining area, Chaharmahal and Bakhtiari, Iran. Al, Fe, Cu, Si and Zn were the most frequent metals in the mining area. Phytoremediation is one of the eco-friendly methods to effectively remediate soils contaminated with heavy metals. Consequently, the wild plants were collected from the mining area and subjected to ICP-OES analysis to determine the elements concentrations. A reverse relation was observed between the metals concentrations and vegetation density in the mining area. Finally, the bioconcentration factor (BCF) of the root and shoot, and translocation factor (TF) were determined to assess phytoremediation potential of species. The shoot elements concentrations in combination with BCF and TF greater than 1 were assess to determine hyperaccumulators and plants with excluder potential. Overall, the results showed that BCF in parallel with TF and metals concentrations can advance the knowledge of recognizing hyperaccumulators for phytoremediation of polluted environment.


2021 ◽  
Vol 5 (1) ◽  
pp. 11
Author(s):  
Kostas Kaklis ◽  
Zach Agioutantis ◽  
Munyindei Masialeti ◽  
Jerome Yendaw ◽  
Thierry Bineli Betsi

The pillar stability factor (PSF) is calculated in three different mining stages for a sublevel open stoping mining project located in northern Botswana. Several three-dimensional finite element models were developed by varying the stope span. Pillar strength was estimated using the Lunder and Pakalnis equation and pillar stress was obtained from the numerical models. As mining progresses, both the first and second mining stages meet the rib pillar stability factor requirement for safe extraction. Geometrical improvements are suggested in the mining layout for the third mining stage to achieve the required PSF, which is based on international practices.


2021 ◽  
Vol 11 (5) ◽  
pp. 157-164
Author(s):  
Dr. Christ Barriga P. ◽  
Ing. Mabel Calderón V.

The gasifiable emulsion is a technological and productive response to the need to reduce operating costs in the mining project, among the improvements with respect to ANFO are a higher detonation velocity (VOD), better fragmentation and reduction of nitrous fumes. In the test mining operation, a commercial explosive mixture called "Q "73 (70% emulsion and 30% ANFO) is used, where the ANFO is composed of 97% ammonium nitrate and 3% diesel, and the explosive mixture "Q "82 (80% emulsion and 20% ANFO) is also used, 7 blasting processes were carried out with a diameter of 12.25 in. in a waste area, the most characteristic rocks found in the blasting project in the copper mine in southern Peru are Toba Cristal (TC), Andesite Basaltic Propylitic (BA-PRO), Andesite Basaltic Argillic (BA-ARG). The results obtained show a reduction of the Power Factor by 1.32%, with respect to the commercial mixtures "Q "73 and "Q "82 an optimum increase in the detonation velocity of 9.92% and 0.59% was obtained, also the high-resolution images of the fumes after blasting indicate a low presence of orange fumes taking a great relevance in the mining sector on a large scale, achieving better results in the blasting phase.


2021 ◽  
Vol 13 (21) ◽  
pp. 4273
Author(s):  
Maoxin Zhang ◽  
Tingting He ◽  
Guangyu Li ◽  
Wu Xiao ◽  
Haipeng Song ◽  
...  

Socioeconomic development is often dependent on the production of mining resources, but both opencast and underground mining harm vegetation and the eco-environment. Under the requirements of the construction for ecological civilization in China, more attention has been paid to the reclamation of mines and mining management. Thus, it is the basement of formulating policies related to mining management and implementing reclamation that detection of mining disturbance rapidly and accurately. This research carries on an empirical study in the Dexing copper mine, Jiangxi, China, aiming at exploring the process of distance and reclamation. Based on the dense time-series stack derived from the Landsat archive on Google Earth Engine (GEE), the disturbance of surface mining in the 1986–2020 period has been detected using the continuous change detection and classification (CCDC) algorithm. The results are that: (1) the overall accuracy of damage and recovery is 92% and 88%, respectively, and the Kappa coefficient is 85% and 84% respectively. This means that we obtained an ideal detection effect; (2) the surface-mining area was increasing from 1986–2020 in the Dexing copper mine, and the accumulation of mining damage is approximately 2865.96 ha with an annual area of 81.88 ha. We also found that the area was fluctuating with the increase. The detected natural restoration was appraised at a total of 544.95 ha in the 1988–2020 period with an average restoration of 16.03 ha. This means that it just restores less in general; (3) it has always been the case that the Dexing mine is damaged by mining and reclamation in the whole year (it is most frequently damaged month is July). All imageries in the mine are detected by the CCDC algorithm, and they are classified as four types by disturbing number in pixel scale (i.e., 0, 1, 2, more than 2 times). Based on that, we found that the only once disturbed pixels account for 64.75% of the whole disturbed pixels, which is the majority in the four classes; (4) this method provides an innovative perspective for obtaining the mining disturbed dynamic information timely and accurately and ensures that the time and number of surface mining disturbed areas are identified accurately. This method is also valuable in other applications including the detection of other similar regions.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Phu Minh Vuong Nguyen ◽  
Tomasz Olczak ◽  
Sywester Rajwa

Abstract It is well-known that the longwall mining method (with roof caving) is widely used in underground mining extraction for bedded deposits (e.g. coal) due to its numerous advantages. Generally, this method is not commonly applied for ore deposits such as copper deposit. In Poland, the longwall mining method has been tested for thin copper deposits at the Polkowice-Sieroszowice copper mine (KGHM). Various failure modes were observed during longwall operation in the 5A/1 panel. This paper aims to examine these occurred failures. To do so, an analysis has been conducted using 3D numerical modelling to investigate the failure mode and mechanism. Based on the 3D numerical modelling results with extensive in situ measurements, causes of failure are determined and practical recommendations for further copper longwall operations are presented.


2021 ◽  
Vol 63 (4) ◽  
pp. 881-910
Author(s):  
Veronika Kusumaryati

AbstractCorporations often claim to be economic actors solely interested in capital accumulation. However, historical and anthropological scholarship has argued they have had outsized political roles, especially during high colonialism when transnational corporations such as the British East India Company and the Dutch East India Company shaped colonial entities. This article explores the case of American mining company Freeport-McMoRan, which runs the world’s largest gold and copper mine in West Papua, and its entanglement with contemporary imperial and colonial projects in the region. Through the study of the company’s decisive role in the transfer of West Papua from the Dutch to Indonesia during the decolonization period of the 1960s, and in the formation of the postcolonial Indonesian state characterized by its militaristic and capitalistic stances, this article argues that Freeport’s operation in West Papua has been central to shaping U.S. imperial policy in Southeast Asia. The company’s relationship with the U.S. government and its contract of work with the Indonesian government reproduce an older form of state-corporation partnership called a charter, which grants a corporate body privileges associated with exploration, trade, and colonization. Combining a historical study of the political role of corporations across time and an ethnographic study of Freeport’s operation, this article rethinks the anthropological and historical study of transnational corporations and their roles in the contemporary politics of colonialism.


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