فصلنامه مهندسی معدن
پیاپی 58 (بهار 1402)

Energy is one of the important inputs in mining. Given the importance of energy in the mining sector and the increase in the price of energy carriers in recent years, analyzing the structure of energy demand is of great importance. This study aims to estimate the demand for energy carriers’ function in operating mines across the provinces of Iran during the period 2009-2017. To do this, using profit maximization, first the energy demand function is derived and then the generalized least squares (GLS) method is used to estimate the model. The results of the study show that the real price of energy in accordance with the law of demand has a negative and significant effect on energy demand, and value added and physical volume of production in operating mines have positive and significant effects on energy demand of carriers. This study also examines the effects of other variables such as the real price of labor and capital and the kind of ownership on energy demand in in operating mines in the provinces of Iran.

Tunneling in urban areas by passing underneath several buildings causes subsidence due to stress relief and development of elastic and plastic deformations. If these subsidences are not controlled, the structures on the ground will be seriously damaged. Nowadays, several methods are used for tunnel analysis and design and for urban tunnels, which excavated in shallow and soft grounds, the best way is using numerical methods. Choosing the Appropriate behavioral model is one of the most basic steps in numerical analysis. tunnel excavation frequently uses the Mohr–Coulomb behavior model in numerical models.The Mohr-Coulomb elastic-plastic model is one of the most widely used models, used in cases evaluating the hardness of materials, independent of the surface tension. If the Mohr-Coulomb used for modeling of tunnel where in depth tunneling excavation is involved and where an increase in maximum ground surface settlement and decrease in the reliability of stability of tunnels can be seen, which may not be appropriate in some conditions. The more appropriate model should be used to solve this problem, one that can model the hardness of materials based on changes in the level of stress.In this study, the effect of different soil parameters on the ground surface settlement of Qom metro line A in Hardening Soil, Mohr–Coulomb and Drager Prager behavior models was investigated using the finite difference method. First, modeling of ground surface settlement was performed and the analysis results were compared with instrumentation data. Then, the effect of modulus of elasticity, friction angle, cohesion, Poisson's ratio and specific gravity parameters in different behavior models was investigated. The results of this research indicated that the Hardening Soil behavior model and the Drager Prager behavior model have the most and the least changes from the changes of soil parameters of Qom metro line A, respectively.

Government management and supervision on mines has always been considered and in some cases due to various legal changes over time or significant jurisprudential views on ownership, the source of government oversight of mines has been interpreted differently and in some cases There may be a suspicion that the recognition of ownership of the mines, or in other words the granting of the usufruct provided for in the laws, will lead to the decline of government sovereignty and control over the mines, so in order to help activists in this field, it seems necessary. The ambiguity of this issue should be removed by examining the laws, and then the type and limits of government supervision over these divine treasures should be determined according to the powers authorized in the laws. This article first examines the laws regarding government control over mines and how to apply them, and finally, while denying ownership and accepting the existence of the right to use mines, despite the fact that mining is allowed by individuals, but the government Exercises its approving supervision by enacting special laws and making the exploitation of individuals conditional on obtaining legal licenses.

Many different lixiviants have been investigated as alternatives to cyanide for gold leaching. Due to environmental, technical, and economic constraints, the industrial application of these alternative methods is still rare up to now. Recent research works have indicated the viability of amino acids and particularly glycine, as an alternative lixiviant to cyanide in the gold industry. In this research, the cyanide-glycine leaching of gold ore has been studied using sign of experiments. The effects of hydrogen peroxide oxidant, cyanide concentration, glycine concentration, and solid content were considered. The results showed that the most effective parameters are solid content, glycine concentration, cyanide concentration, and oxidant concentration, respectively. Gold recovery decreased by increasing solid content, glycine concentration, and cyanide concentration. The maximum gold recovery was achieved when these parameters are at their lowest levels. In optimum conditions, 81% gold recovery could be obtained at 2.49% hydrogen peroxide, 150 ppm cyanide, 0.35 mol/L glycine, and 25% solid content.

Pouya Zarkan Aq Dareh gold factory is located 32 km north of Takab city in Azerbaijan province and its gold is recovered by cyanide, adsorption on activated carbon and electrovining. Cyanide causes many environmental problems due to its toxicity and danger. In this study, the amino acid L-valine was used as a gold leach agent for cheap and non-toxic replacement, and parameters such as the concentration of the amino acid L-valine were used. , Temperature, pH and time were considered as effective parameters in the dissolution of the test design method and finally under optimal conditions the concentration of amino acid L-valine 300 g / t, temperature about 60 ° C, pH equal to 11.37 And the time of 32 hours of gold recovery was about 88.83%, while on this mineral (with dimensional specifications and fixed grade) by performing the cyanation process at a concentration of 300 g / ton, the maximum gold recovery reached 90% and 150 g / Tons of cyanide remain unused in the leach solution, which in addition to increasing the cost of chemicals used in the leaching process, will also cause environmental problems that require the solution to be neutralized before being transferred to the tailings dam

The sliding area under investigation is located in the central Alborz domain and situated at south of the north drift of Tehran with a slope to the north. The presence of this drift has caused the different units of tuff and conglomerate to be juxtaposed. It should be emphasized that electrical resistivity measurements are deployed along four profiles by collecting 31 electrical soundings in the study area. The maximum current has been transmitted up to a depth of 600 meters. The method of data collection is based on a Schlumberger array with the same station spacing. Electric sounding methods are used because of their good agreement with geological and well log information and core analysis. Upon geoelectric modeling, electrical resistivity cross sections of landslide surface were prepared. In order to extract a more accurate model from the landslide surface, refraction seismic was surveyed along three profiles, where the distance between the receivers (geophones) was 8 to 10 meters. By designing 9 seismic shots along each profile, the first arrival times were used for modeling. On each profile, the distances from the first geophone were assumed to be 30 and 50 meters. By inverse modeling of the first arrival travel time of rays along the path from the source to the geophone, the primary wave velocity model was imaged. In particular, focusing on comparing the inverted models of the geophysical methods, an accurate subsurface model of the possible landslide surface will be provided based on the models of electrical resistivity and seismic propagation velocity.

The 1:100,000 scale Chahar-Farsakh sheet in South Khorasan province has a high potential for regional exploration.due to its volcanic and plutonic rocks and the presence of metamorphic rocks containing mineralization and metal indices. Determination of composite geochemical anomalies for 20 elements by spectral clustering method on the stream sediment data of this sheet suggests 6 areas for mineralization. In the second stage, Sentinel 2A satellite images of the study area were used because they had more bands and higher spatial resolution of 10 and 20 meters. By clustering the sentinel 2A satellite images into 5 clusters, the optimal clustering obtained with Silhouette index shows that the spectral behavior of the second cluster pixels is similar to the spectral behavior of igneous and metamorphism rocks. Therefore, two geochemical anomaly areas located in this cluster have been proposed as the first priority of mineralization according to other exploration data. The pixels of the fourth cluster have a spectral behavior similar to sedimentary rocks, and the two geochemical anomaly areas located in this cluster are considered for the second exploration priority. Comparing the location of the pixels of the first, third and fifth clusters with the geological map of the study area and studying their spectral behavior also shows that these clusters overlap with the Quaternary alluvial and terrace sediments, which have not the value of mineralization. The results of this study show that the clustering of the satellite data can be used to validate regional geochemical anomalies and to prioritize them.