Effects of Pregnant Leach Solution Temperature on the Permeability of Gravelly Drainage Layer of Heap Leaching Structures
mehdi
amini
School of Mining Engineering, College of engineering, University of Tehran, Tehran, Iran
author
text
article
2013
eng
In copper heap leaching structures, the ore is leached by an acidic solution. After dissolving the ore mineral, the heap is drained off in the acidic solution using a drainage system (consisting of a network of perforated polyethylene pipes and gravelly drainage layers) and is, then, transferred to the leaching plant for copper extraction where the copper is extracted and the remaining solution is dripped over the ore heap for re-leaching. In this process, the reaction between the acidic solution and copper oxide ore is exothermal and the pregnant leach solution (PLS), which is drained off the leaching heap, has a higher temperature than the dripped acidic solution. The PLS temperature variations cause some changes in the viscosity and density which affect the gravelly drainage layer's permeability. In this research, a special permeability measuring system was devised for determining the effects of the PLS temperature variations on the permeability coefficient of the gravelly drainage layer of heap leaching structures. The system, consisting of a thermal acid resistant element and a thermocouple, controls the PLS temperature, which helps measure the permeability coefficient of the gravelly drainage layer. The PLS and gravelly drainage layer of Sarcheshmeh copper mine heap leaching structure No. 1 were used in this study. The permeability coefficient of the gravelly soil was measured against the PLS and pure water at temperatures varying between 3°C to 60°C. Also, the viscosity and density of the PLS and pure water were measured at these temperatures and, using existing theoretical relations, the permeability coefficient of the gravel was computed. A comparison between the experimental and theoretical results revealed a good conformity between the two sets of results. Finally, a case (Taft heap leaching structure, Yazd, Iran) was studied and its gravelly drainage layer was designed based on the results of the present research.
International Journal of Mining and Geo-Engineering
University of Tehran
2345-6930
47
v.
2
no.
2013
91
102
https://ijmge.ut.ac.ir/article_51330_b99b9f527c1c6f64545ca19c8204ff9e.pdf
dx.doi.org/10.22059/ijmge.2013.51330
Hydrograph Modeling Using SGSim: A Case Study of Behbahan Aquifer, Southwest of Iran
Amir
Mollajan
M.Sc., Mineral Exploration Engineering, School of Mining Engineering, University College of Engineering, University of Tehran
author
Omid
Asghari
Assistant professor, Simulation & Data Processing Laboratory, School of Mining Engineering, University College of Engineering, University of Tehran
author
text
article
2013
eng
Hydrograph modeling and prediction of groundwater levels are the main concerns of most hydrogeological calculations and water resource management process. The present study is an application of Sequential Gaussian Simulation (SGSim) method for predicting groundwater levels using recorded monthly data (180 months) related to 21 piezometers of Behbahan aquifer, southwest of Iran. To generate realization maps through SGSim method, data were transferred to Gaussian distribution and then simulated 10 times for each month. Then, E_Type maps were produced to obtain hydrograph of interest. Finally, the iterative Box and Jenkins method was used to model the obtained hydrograph. The capability of the resulted ARIMA (0, 1, 1) model was examined by calculating coefficient of determination (R2) and estimated root mean squared error (RMSE). For the obtained model, R2 and RMSE were equal to 0.79 and 1.93, respectively. Drawing on the obtained hydrograph, it can be concluded that there is a significant decrease in groundwater level in the plain for upcoming months.
International Journal of Mining and Geo-Engineering
University of Tehran
2345-6930
47
v.
2
no.
2013
103
113
https://ijmge.ut.ac.ir/article_51331_c34fcc461ea02d3d72843fab91fb7009.pdf
dx.doi.org/10.22059/ijmge.2013.51331
Applying rock engineering systems (RES) approach to evaluate and classify the coal spontaneous combustion potential in Eastern Alborz coal mines
Amir
Saffari
Faculty of Mining Engineering, Petroleum and Geophysics, Shahrood University of Technology, Shahrood, Iran
author
Farhang
Sereshki
Faculty of Mining Engineering, Petroleum and Geophysics, Shahrood University of Technology, Shahrood, Iran
author
Mohammad
Ataei
Faculty of Mining Engineering, Petroleum and Geophysics, Shahrood University of Technology, Shahrood, Iran
author
Keramat
Ghanbari
HSE Management of Eastern Alborz Coal Mines Company
author
text
article
2013
eng
Subject analysis of the potential of spontaneous combustion in coal layers with analytical and numerical methods has been always considered as a difficult task because of the complexity of the coal behavior and the number of factors influencing it. Empirical methods, due to accounting for certain and specific factors, have not accuracy and efficiency for all positions. The Rock Engineering Systems (RES) approach as a systematic method for analyzing and classifying is proposed in engineering projects. The present study is concerned with employing the RES approach to categorize coal spontaneous combustion in coal regions. Using this approach, the interaction of parameters affecting each other in an equal scale on the coal spontaneous combustion was evaluated. The Intrinsic, geological and mining characteristics of coal seams were studied in order to identifying important parameters. Then, the main stages of implementation of the RES method i.e. interaction matrix formation, coding matrix and forming a list category were performed. Later, an index of Coal Spontaneous Combustion Potential (CSCPi) was determined to format the mathematical equation. Then, the obtained data related to the intrinsic, geological and mining, and special index were calculated for each layer in the case study (Pashkalat coal region, Iran). So, the study offers a perfect and comprehensive classification of the layers. Finally, by using the event of spontaneous combustion occurred in Pashkalat coal region, an initial validation for this systematic approach in the study area was conducted, which suggested relatively good concordance in Pashkalat coal region.
International Journal of Mining and Geo-Engineering
University of Tehran
2345-6930
47
v.
2
no.
2013
115
127
https://ijmge.ut.ac.ir/article_51333_eb6dee38416be362ed956df9e3aed27c.pdf
dx.doi.org/10.22059/ijmge.2013.51333
A New Algorithm for Determining Ultimate Pit Limits Based on Network Optimization
Ali Asghar
Khodayari
School of Mining Engineering, College of engineering, University of Tehran, Tehran, Iran
author
text
article
2013
eng
One of the main concerns of the mining industry is to determine ultimate pit limits. Final pit is a collection of blocks, which can be removed with maximum profit while following restrictions on the slope of the mine’s walls. The size, location and final shape of an open-pit are very important in designing the location of waste dumps, stockpiles, processing plants, access roads and other surface facilities as well as in developing a production program. There are numerous methods for designing ultimate pit limits. Some of these methods, such as floating cone algorithm, are heuristic and do not guarantee to generate optimum pit limits. Other methods, like Lerchs–Grossmann algorithm, are rigorous and always generate the true optimum pit limits. In this paper, a new rigorous algorithm is introduced. The main logic in this method is that only positive blocks, which can pay costs of their overlying non-positive blocks, are able to appear in the final pit. Those costs may be paid either by positive block itself or jointly with other positive blocks, which have the same overlying negative blocks. This logic is formulated using a network model as a Linear Programming (LP) problem. This algorithm can be applied to two- and three-dimension block models. Since there are many commercial programs available for solving LP problems, pit limits in large block models can be determined easily by using this method.
International Journal of Mining and Geo-Engineering
University of Tehran
2345-6930
47
v.
2
no.
2013
129
137
https://ijmge.ut.ac.ir/article_51334_d61ec42b11a4b66b4f73345d33c62c14.pdf
dx.doi.org/10.22059/ijmge.2013.51334
Identification of the Origin and Behaviour of Arsenic in Mine Waste Dumps Using Correlation Analysis: A Case Study Sarcheshmeh Copper Mine
Saeed
Yousefi
Ph.D. candidate, Faculty of Mining, Petroleum and Geophysics, Shahrood University, Shahrood, Iran
author
Faramarz
Doulati Ardejani
Professor of Environmental Hydrogeology, Faculty of Mining, Petroleum and Geophysics, Shahrood University, Shahrood, Iran
author
Mansour
Ziaii
Assistant Professor of Geochemistry, Faculty of Mining, Petroleum and Geophysics, Shahrood University, Shahrood, Iran
author
Esmat
Esmaeil Zadeh
National Iranian Copper Industries Company (NICICO)
author
Arezoo
Abedi
Assistant Professor of Economic Geology, Faculty of Mining, Petroleum and Geophysics, Shahrood University, Shahrood, Iran
author
Mohammad
Karamoozian
Assistant Professor, Mineral Processing, Shahrood University, Shahrood, Iran
author
text
article
2013
eng
Knowledge of the probable origin and behaviour of arsenic certainly gives valuable insights into the potential for transfer in the environment and of the risks involved in mining sites. Sequential extraction analyses are common experiments often used to study the origin and behaviour of potentially toxic elements. The method, however, presents some deficiencies, including labor-intensive procedure, interferences of phases, being impractical for testing large number of samples in heterogeneous environment as well as inability for determining the individual minerals as source or sink terms for toxic elements. This study attempts to determine the origin and behaviour of arsenic in waste dump using correlation analysis approach. To this end, sixty samples were collected from two waste dumps at the Sarcheshmeh Copper Mine in Kerman Province, Iran. The statistical results along with previous experimental investigations and also sequential extraction experiment revealed that adsorption on muscovite is the main source, and that oxy hydroxides of iron and manganese are the main adsorbent minerals which control the concentrations of arsenic in the waste dumps of the Sarcheshmeh copper mine.
International Journal of Mining and Geo-Engineering
University of Tehran
2345-6930
47
v.
2
no.
2013
139
149
https://ijmge.ut.ac.ir/article_51336_f06d95512a35f5ef6ab90410a390e253.pdf
dx.doi.org/10.22059/ijmge.2013.51336
The Impact of Anjir –tangeh Coal Washing Plant on Concentration of Some Heavy Metals in the Native Vegetation, Mazandaran Province, Iran
Samaneh
Safari Sinegani
PhD Student, School of Mining, Petroleum & Geophysics Engineering, Shahrood University of Technology
author
Arezoo
Abedi
School of Mining, Petroleum & Geophysics Engineering, Shahrood University of Technology
author
Hamidreza
Asghari
School of Agricultural Engineering, Shahrood University of Technology
author
Ali Akbar
Safari Sinegani
Faculty of Agriculture, Department of Soil Science, Bu-Ali Sina University
author
text
article
2013
eng
A large volume of tailings has been produced in Anjir-tangeh coal washing plant for 22 years of human activity. The coal washing activities have reduced plant diversity near the plant. The environmental impact of coal washing plant on the vegetation around the factory was studied in two seasons. The concentrations of Pb, Cd and Cr, measured in different native plant species, were in normal ranges in summer. In fall, the concentrations of Pb, Cd and Cr in the plants around the factory were similar to those in plants in the control area. In summer, however, the metal concentrations were considerably higher in plants grown near the factory than in the plants of the control area. This difference was statistically significant at 0.01 levels for Cd, but not for Pb and Cr. Among the studied plant species, Oxalis Sphad the highest Cd concentration (0.409 ppm), but Chenopodium album L had the lowest Cr concentration in summer. Season was an effective factor in the uptake of heavy metals by plants; metal concentration in plants was considerably higher in fall than in summer.
International Journal of Mining and Geo-Engineering
University of Tehran
2345-6930
47
v.
2
no.
2013
151
161
https://ijmge.ut.ac.ir/article_51338_ecee3d25a37cdd0562553c70566d296b.pdf
dx.doi.org/10.22059/ijmge.2013.51338
Three-Dimensional Geostatistical Analysis of Rock Fracture Roughness and Its Degradation with Shearing
Nima
Babanouri
Department of Mining Engineering, Shahid Bahonar University of Kerman, Kerman, Iran
author
Saeed
Karimi Nasab
Department of Mining Engineering, Shahid Bahonar University of Kerman, Kerman, Iran
author
text
article
2013
eng
Three-dimensional surface geometry of rock discontinuities and its evolution with shearing are of great importance in understanding the deformability and hydro-mechanical behavior of rock masses. In the present research, surfaces of three natural rock fractures were digitized and studied before and after the direct shear test. The variography analysis of the surfaces indicated a strong non-linear trend in the data. Therefore, the spatial variability of rock fracture surfaces was decomposed to one deterministic component characterized by a base polynomial function, and one stochastic component described by the variogram of residuals. By using an image-processing technique, 343 damaged zones with different sizes, shapes, initial roughness characteristics, local stress fields, and asperity strength values were spatially located and clustered. In order to characterize the overall spatial structure of the degraded zones, the concept of ‘pseudo-zonal variogram’ was introduced. The results showed that the spatial continuity at the damage locations increased due to asperity degradation. The increase in the variogram range was anisotropic and tended to be higher in the shear direction; thus, the direction of maximum continuity rotated towards the shear direction. Finally, the regression-kriging method was used to reconstruct the morphology of the intact surfaces and degraded areas. The cross-validation error of interpolation for the damaged zones was found smaller than that obtained for the intact surface.
International Journal of Mining and Geo-Engineering
University of Tehran
2345-6930
47
v.
2
no.
2013
163
179
https://ijmge.ut.ac.ir/article_51340_ff2786df681b19a9505892c176afea11.pdf
dx.doi.org/10.22059/ijmge.2013.51340