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Article Flotation of Refractory Marmatite Ore by Using Ammoniacal Copper (ii) Solution as Activator(The International Journal of Mineral Resources Engineering, 2008) Rao, Feng; Song, Shaoxian; Tong, Xiong; Xıe, Xian; Lopez-valdıvıeso, AlejandroThe flotation of a refactory marmatite ore in China has been studied by using ammoniacal copper (II) solution as the activator in this work, in order to improve the Zn recovery of the marmetite flotation. The experimental results have shown that the ACS could increase the Zn recovery of 9%, compared withcopper sulphate (a commonly used activator for sphalerite and marmatite). The marmatite flotation with the ACS as activator consume much less lime because it was realized at pH 9, while that with copper sulphate as the activator is carried out around pH 12. The less lime consumption not only leads to savings on operation costs, but also reduces the corrosions of flotation celss and stirring tanks, etc. The mechanism by which the ACS acts as activator in marmatite flotation has been found to be attributed to the chemical adsorption of copper (II)-ammonia complexes (CuNH32 and Cu(NH3)22) on marmatite surfaces, leaving to active sites on the surfaces for the adsorption of xanthate ions.Article Unconventional Natural Gas From Abandoned Coal Mines: Modelling and Performance Prediction at the Frankenholz-St. Barbara Mining Complex(The International Journal of Mineral Resources Engineering, 2007) Durucan, Şevket; Shı, Ji-quan; Korre, AnnaThis paper describes a joint research project carried out by Imperial College and Deutsche Steinkohle Aktiengesellschaft (DSK), in which the Imperial College in house gas-water two-phase Coalbed Methane (CBM) simulator was further developed to model abandoned mine methane recovery in the Saar Coalfield. Historical data on mining and methane emissions, as well as the long-term methane production data monitored at the Hangard shaft was used to validate the model developed. A satisfactory match tothe historical and currrent field data was achieved. Predictionsfor future production opportunities were made for the Allenfeld shaft in conjunction with production from the Hangard shaft which has been in production since 1960.Article A Company-Perspective Cost Analysis of the Personal Dust Monitor (pdm)(The International Journal of Mineral Resources Engineering, 2007) Reed, W.r.; Volkweın, J.c.; Joy, G.j.The personal dust monitor (PDM) is a new coal mine respirable dust sampling instrument that has the ability to provide accurate end-of-shift and real-time respirable dust exposure data. A hypothetical cost comparison analysis of the PDM with the current MSHA-required coal mine dust personal sampling unit (CMDPSU) was conducted. Some simplifying assumptions were made to create hypothetical cases for analysis. This analysis was limited to respirable dust sampling of the one designated operator (DO) and one designated area (DA) for one mechanized mining unit (MMU) which operated one shift per day. Only sampling intervals of the minimum sampling as required by federal regulations and continuous sampling were analyzed. This cost analysis from the company perspective is only one part of an overall cost/benefit analysis that should be conducted at a later date. In this analysis, company-associated costs were examined for both sampling systems. Results show that the PDM, while it has high initial costs of approximately $ 12,600, may be a cost-effective sampling system for measuring coal mine respirable dust. The estimated present worth cost of conducting the minimum requried dust sampling over a five-year life ranges from $5,850 to $19,000 for the CMDPSU, with the higher present worth cost including costs of potential violations incurred. For the PDM, the comparable present worth cost is $14,900 to $19,300, with the lower present worth cost representing a lower capital cost of $8,150 per unit if more than 850 units are produced per year, while the higher present worth cost reflects the results with the higher $12,600 capital cost.Article Quality Cost Assessment in Mine Tunnelling With Drilling and Blasting(The International Journal of Mineral Resources Engineering, 2007) Kenzap, Serguei A.; Kazakıdıs, Vassilios N.A decision making process for equipment selection in mine lateral development is presented. This addressess the need of mine development projects to increase actual lateral development rates for single headings using drilling and blasting techniques. The approach described in this papaer focuses on quality issues in a lateral development cycle by linking them to the "time value of money" concept. Th total poor quality cost estimation in lateral development is presented in case study #1, where typical lateral development practice at Falconbridge Ltd (now Xstrata Nickel) in the Sudbury basin was analyzed. A conceptual example, presented in case study#2, showa the practical application of the proposed approach and emphasizes the benefits of discrete event simulation in conjunction with process quality quantification in mine lateral development.Article A CALCULATION METHOD FOR A SHOVEL-TRUCK SYSTEM WITH AN INCLINED HOIST OF TRUCKLIFT TYPE(The International Journal of Mineral Resources Engineering, 2008) Czaplıckı, Jacek M.The proposal to apply an inclined hoist of the Trucklift type in open pit mining hung in mid-air. Although this suggestion is quite interesting, no mine around the world was interested in such an installation. It appears that one of the main reasons for which the proposal missed its aim was the lack of the method of analysis and calculation of shovel-truck systems including such a type of hoist to allow an assessment of what kind of improvement might be expected if the hoist is employed in the system. This paper shows the method of analysis and calculation of shovel-truck systems with a hoist, considering the majority of the important compenents that have an influence on the course of the operation/exploitation process of the machinery system. An example is given to add to the communicativeness of the considerations and conclusions drawn.Article Bin Volume Selection in Relation To Hoist Output and Stream of Rock Extracted-Analysis of the System(The International Journal of Mineral Resources Engineering, 2008) Czaplıckı, Jacek M.This paper conducts an analytical description of the problem of shaft bin volume selection in relation to the hoist output given and to the stream of rock mass delivered to the shaft. Special attention is devoted to the stochastic nature of phenomena occurring during ine operation. The stream of mass transported is identified as the Gaussian and the hoist daily output as the random variable that can be described by a modified beta distribution. The bin volmu is considered as a function of either the average value by which the rock mass exceeds the hoisting capacity of transportation both per day or the average rock mass that is delivered to the shaft during the mean time of hoist repair plus the corresponding standard deviation of thise repair time. The rock mass fluctuation in the bin is also taken into account, and its effect included in the calculation procedure.Article The Co2 Footprint of The U.s. Mining Industry and The Potential Costs of Co2 Legislation(The International Journal of Mineral Resources Engineering, 2008) Azız, Abdulmajeed; Kecojevıc, VladislavThe purpose of this study is to estimate the carbon dioxide (CO2) emissions or footprint of the U.S. mining industry, and based on potential CO2 legislation estimate the cost of industry's footprint. The CO2 footprint is calculated by using a limited Life Cycle Assessment (LCA) method, and the cost implications to the mining industry are evaluated using two well-known CO2 legislation frameworks: U.S. Energy Information Agency's (EIA) the National Energy Modeling Systems (NEMS) model, and Massachusetts Institute of Technology's (MIT) Emissions Prediction and Policy Analysis (EPPA) model. The results of this study indicate that the mining industry currently emits 97.17 million tonnes of CO2 annually. In an effort to reduce CO2 emissions levels into the atmosphere, the government is expected to develop a federal mandate that will be structured as a CO2 tax and/or through a cap and trade system, such as that proposed by the Lieberman-Warner Climate Security Act of 2008. Following suit with this bill, cumulative estimated costs of a federal cap and trade system on the mining industry between 2012 and 2050 is projected to range from $162 to $417 billion.Article Investigations Into Imgi Dump-Site Hydrology, Sub-Surface Water Amd and Soil/Material Characterization To Assess Baseline Data and the Pollution Potential To Soo-Young River(The International Journal of Mineral Resources Engineering, 2008) Bhattacharya, Jayanta; Yım, Gil Jae; Jı, Sang Woo; Lee, Hyeon Seok; Mın, Jeong Sık; Cheong, Young WookDump site leachates, augmented by surface oxidation and solubilization of cations and anions, and are causing widespread distribution of potential pollutants to the Imgi stream. This study examines the surface physical, geochemical and hydrological characteristics to assess the release of various metals and sulfate. The study also examines the surface water transport of selected ions in the stream to assess non-reactive and sedimentation prospects of different ions. Further, The local soil characterization vis-a-vis unaltered soil was also made to determine the pyhsical degradation.Article A Study on Thermal Decomposition of Dolomite From West Anatolia Region Using Semi-Pilot Scale Rotary Furnace(The International Journal of Mineral Resources Engineering, 2013) Derin, Bora; Demircan, Umut; Uzunoğlu, Timur; Yücel, OnuralpDecomposition behaviour of dolomite from the western Anatolia region (Turkey) was investigated using semi-pilot scale rotary furnance as a part of magnesium production project. Experiments were carried out using 1000 g of dolomite samples at different temperatures (800-1100 °C) and time (0-300 min). It was found that be decomposition process increased with increasing time and temperature. TG/DTA and XRD analysis showed that dolomite decomposition followed two stage reactions; first is formation of CaCO3 and MgO, the second is following CaCO3 decomposition. Decomposition mechanism of semi-pilot experiments was found to be first order reaction with activation energy of 126.8 kJ mol-1.
