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By Wojciech Naworyta

The development of the Gubin lignite deposit, located in western Poland is the first mining investment of this magnitude in 30 years. Gubin is the second largest prospective lignite deposit in Poland, with over one billion tonnes of indicated reserves, which would be sufficient for a 2700 MW power plant for almost 50 years. The paper presents select problems related to the mining development of Gubin deposit. Attention has been paid to changes in legal and formal requirements for mining investments that were introduced after the change of Polish social and economic system. The significance of spatial, environmental and social conditionings has been emphasized. Typical attributes of the mine planning process have also been presented. Those include the long time horizon of the investment, uncertainty of external conditions and resulting difficulties in the project?s economic evaluation. Focus has been placed on mutual connections between particular elements of the project and time dependence during the process of their development. Iterative characteristics of the design process have been proven, together with resulting necessity of frequent verification of previous assumptions. As a background for presenting selected problems related to future development of Gubin lignite deposit, the methods of design have been discussed ? the variants method, the empirical method and the method of consecutive approximations. The tools and the possibilities of their use for solving specific problems related to mine design of an open pit have been broadly discussed. The chapter in which the authors relate to the specific problems of Gubin deposit development constitutes the main part of the paper. It depicts the assumptions on which the annual production and the total extraction of lignite during life-of-mine period have been based. The process of mine designing has been discussed, taking into consideration environmental, geotechnical, spatial, social and mining conditions. The criteria for choosing the location of the opening cut and the external dump have been mentioned. In the summary, the present state of mine design progress has been presented, together with some problems that will need to be solved during the next stages of the deposit?s development.

Aug 1, 2013

By G. Reuben Yourt

This paper consists of two main parts. The first, under the heading Preparations, deals with suggested preparations to be carried out in advance so that loss of life might be prevented should a fire occur. The second part, under the heading Fire Procedure, deals with actual organized procedure to be followed for the preservation of life if and when a fire occurs. The writer realizes that these preparations and procedures may be to some extent applicable to only a few mines with a relatively simple vein system and that each mine would need to formulate a procedure to conform to its own particular conditions, scope, and degree of complexity. Preparations 1. - Ventilation Control The objective in ventilation control in the event of a tire underground is to keep the travelways, through which men must pass to reach surface, supplied with air not deficient in oxygen and free from gases and smoke. Without some control of the volume and direction of the main air currents flowing through the mine, the success of removing men to surface might be seriously hampered. ? This control is achieved by means of mechanical ventilation forcing air through desired airways and workings with the assistance of doors to regulate the volume and direction of the air flow. In connection with fans and doors, the possibility of short-circuiting should always be taken into consideration, as it can often nullify the value of a fan and possibly trap men in dangerous atmosphere if the short-circuiting involves the fire area. Main fans are often installed so that they can be reversed in a short time. However, fans should not be reversed unless this is found absolutely essential by those in authority. Misjudgment in this respect could cause the loss of life to men who might naturally take refuge in what they believe by experience to be a fresh air stream. Another precaution to be taken is to see that doors in airways are fastened in a fixed position so that they cannot be sucked or blown open when the fan is reversed, otherwise short-circuiting could possibly render the fan useless.

Jan 1, 1947

By J. Shanks

In 1920 the writer presented some notes, embodying his experience with storage-battery locomotives as main under-ground haulage-motors at Brazeau collieries. (1) Since that date these motors have stood up well to the test of maximum output and heavy overloads, having accomplished all that was expected of them. The notes presented in 1920 gave a brief description of the conditions under which these motors were working at Brazeau collieries, also the cost, per ton mile, of operating them. The cost per ton mile has since then been appreciably reduced, by working the locomotives nearly to capacity and under more ideal haulage conditions, on both shifts. It is not the intention of the writer to repeat what was written in 1920, but rather to give members the benefit of his experience in operating different types or designs of locomotives; to draw their attention to the drawbacks of some designs, and to the improvements made in some of the more recent storage-battery locomotives put on the market, as regards efficiency, upkeep, and safety. Because of their flexibility storage-battery locomotives have advantages over any other type of haulage, where grades are suitable to their use. The number in use in the mines in the United States has increased enormously during the past few years, and this method of haulage is, at the present time, attracting the attention of British and Continental mining engineers.

Jan 1, 1924

By B. P. Verma, K. N. Sinha, N. M. Raju, B. Singh

The paper describes a new method of grouting bolts developed at the Central Mining Research Station at Dhanbad in India. This method makes use of wire-mesh sleeve instead of the expensive metal tube to insert the cement mortar into the drill hole. The field trials confirmed that the method is cheap and an effective system of support.

Jan 1, 1972

By SangHyeok Han

Selecting the best possible cranes and identifying spatial conflict-free locations on sites can result in productivity and safety improvements for large-scale industrial construction projects. In the current practice, experienced lift engineers select cranes based on the heaviest lift and/or the largest lifting radius of the identified crane. This practice is relatively time-consuming, and optimization of the crane?s use and location is also difficult. There are many factors which need to be considered during the crane selection process, a reality which further complicates the process. This paper presents a framework which aims at developing a decision support system to enhance the crane selection process and collision-free path planning for large-scale construction projects. This paper utilizes an innovative crane selection matrix in order to establish a process for optimized crane selection for construction projects. The study considers more than 40 different factors in order to reduce time and improve safety for crane operations. Following finalization of crane type (mobile crane versus tower crane), a visualization model to simulate crane operation and identify collision-free crane operation paths is proposed. This process can assist project managers to plan the lifting process more effectively and efficiently. A case study-based approach was utilized to demonstrate the proposed methodology. The methodology was tested in the planning and construction process for boiler house structures in Mannheim, Germany. The project entailed numerous challenges: one of the major tasks was to lift a 102-ton load on the top of the boiler structure through crane collaboration; space limitations on site also presented several challenges related to crane selection, location, and operation processes. Based on the project constraints, the proposed crane selection framework, and the visualization models, two tower cranes were selected and successfully implemented in the case study.

Aug 1, 2013

By Alisa M. Caswell

Outline: 1. Syncrude: Who are We? 2. Energy Use at Syncrude 3. Historical Energy Focus at Syncrude 4. Case Studies for Process Variable Monitoring 5. Extraction Flood Water Temperature Management 6. Fired Heater Tuning 7. Critical Factors for Success Syncrude: Who are We? ?Syncrude is a Joint Venture Operating Company with one product: Synthetic Crude ?Production Capacity: 350 kbbls/day ?Primary Energy Sources: ??Fuel Gas + Natural Gas ?? Coke ?? Electricity ?? Diesel

May 1, 2008

By Richard Hurteau

Design and validation of an integrated guidance system for articulated ground vehicles is investigated. The development of an autonomous industrial vehicle must take into the account the specific geometry of these vehicles; they can be composed of a tractor with 1 or 2 trailers or of articulated type like LHD. Moreover the tractor-trailers type vehicles can have on-axle hitch configuration or positive/negative off axle configuration. The path-tracking of a tractor-trailer vehicle in restricted space is presented and discussed in this paper. Recent results obtained in simulation and validated by experimentation are also presented. These studies can lead to better ways of maneuvering an articulated vehicle in a restricted space or automatically executing of docking and parking maneuvers

May 1, 2002

By J. Olsson

The paper describes and discusses the use of stainless steels for leaching plants emphasising the duplex family, i.e., austenitic-ferritic stainless steels. This group has generally twice the proof strength of the more common 300-series austenitic grades, which implies possibilities to reduce the gauge at construction of pressure vessels and atmospheric tanks and vessels and thereby possibilities to reduce the weight. The duplex grades have also higher surface hardness resulting in better resistance to mechanical wear, i.e., abrasion and erosion corrosion. The lower contents of nickel and molybdenum imply lower cost and a more stable price considering the present market situation for these alloying elements. Corrosion data from laboratory and pilot plant tests, as well as examples of applications of duplex and highly alloyed austenitic grades, are presented. Cu2007 - Volume IV (Book 1) The John E. Dutrizac International Symposium on Copper Hydrometallurgy Edited by P.A. Riveros, D.G. Dixon, D.B. Dreisinger, M.J. Collins Toronto, Canada,

Jan 1, 2007

By P. E. Georghiou, S. Shafiei Zadeh, H. Hassan Nejad

Data are presented on the extractant behaviour on toxic metal removal from spent hydroprocessing catalyst, produced at the North Atlantic Refinery plant in Newfoundland and Labrador. Aliquat 336 was selected due to its potential capabilities for the separation of cobalt, molybdenum and nickel from the leachate extractant produced by aqua regia. The solvent extraction process was statistically modeled using central composite design (CCD), and the numerical optimization was conducted to achieve the optimum point for toxic metal recovery for the extractant.

Jan 1, 2014

By M. Connell, S. Bedrossian

Alkali cracking followed by chloride-based leaching is one of the prominent methods for rare earth element processing. Regeneration of the leach lixiviant, namely hydrochloric acid, is a critical operation in the process. A number of different process routes are available for recovery of hydrochloric acid from chloride solutions. The objective of this paper is to discuss various recovery routes and analyze the impact of several input variables on the variable operating cost.

Jan 1, 2014

By M. Maeda, H. Sasaki

Dissolution characteristics of metals vary significantly when they form alloys with other elements. Because hydrometallurgical processes are essential in separation and refining of non-ferrous metals, it is important to study behaviors of alloys in aqueous solutions. The authors have studied dissolution characteristics of precious metals in acid solutions using electrochemical measurement. When precious metals are alloyed with Zn, its dissolution is promoted by an increase in surface area caused by the preferential dissolution of this metal. The electrochemical study also revealed that precious metals dissolved from some alloys at unusually negative potentials; the underpotential dissolutions are explained by activations of these metals in the dealloying.

Jan 1, 2014

By Marcel Laflamme

Underground mine workers are continuously exposed to many sources of noise and vibration in carrying out their tasks. Even though the vibration and sound level of some mining equipment is documented, it was found that this information is not readily available for many pieces of equipment and that it is not considered when choosing equipment or planning tasks. As well, health problems related to vibration and noise are among the main causes of work-related compensations in mines. Considering those facts and although no Canadian regulations could force employers to limit the exposure of their workers to vibration, the Société de recherche et développement minier (SOREDEM) decided to address the problem by including vibration among their research priorities. In order to characterize noise and vibration sources of different mining equipment used for underground mining, the authors have performed a study in 8 different mines in Québec on 28 different mining equipments. The paper will present the procedure that was followed to select the list of equipment to be evaluated and the low cost acquisition system developed to perform multichannel time domain acquisition in harsh environments. It will also present the results obtained for the noise level produced by the equipment as well as for the hand-arm and whole-body vibration exposures.

Aug 1, 2013

By K. Adham, C. T. Harris

Arsenic is often associated with copper, nickel and gold in sulphide deposits. This paper describes a two-stage high-temperature fluid bed reactor for the removal and fixation of As from ores and concentrates. The first (bottom) stage of reactor removes the As through a neutral roast, by volatilization as mostly sulphide species. The second (top) stage of reactor captures the As from the gas phase through oxidative fixation, as a stable iron arsenate, by reaction with an appropriate iron source (sulphide or oxide). The second stage is placed on top of the first, so that their combined function can be achieved in a simple two-stage fluid bed arrangement, with the bottom stage off-gas providing the top stage fluidization.

Jan 1, 2014

By D. T. Smith, S. J. Strohmayr

Originally developed as a step change in ultrafine grinding efficiency, the IsaMill™ has made inroads into conventional ball mill and tower mill mainstream grinding duties during the last 5 years - beginning with the Anglo Platinum mainstream grinding projects in South Africa. At the 2006 SAG Conference, plant testwork on the incorporation of IsaMill™ technology into the McArthur River (Northern Territory, Australia) Pb/Zn primary grinding circuit was reported. The IsaMill™ has now become an integral component of that circuit, treating up to 1mm top size feed and directly producing P80 45 µm rougher flotation feed. Two 1.1 MW IsaMills™ are now used in this duty contributing to a 27% increase in overall plant throughput and a reduction in rougher feed size distribution. In this paper, we report on the current state of development and performance of the IsaMill™ in the primary grinding duty at McArthur River and also consider future directions.

Jan 1, 2012

By H. Wilhelm, W. I. van Drunick

The Anglogold Ashanti (AGA) Navachab single stage SAG mill has provided an excellent setting for incremental optimization. Over the past decades, several interventions have resulted in marked improvements in specific performance; including steel ball scat removal, re-design of the mill lifters, replacement the pebble crusher and cyclone cluster, as well as the use of a vibrating screen in place of a discharge trommel. Recent initiatives now include an operating fine DMS circuit, studies on pre-crushing of the ROM feed and also fine-screening as an alternative to hydrocyclone classification. The current optimized state of the Navachab mill allows it to operate at approximately 20% higher efficiency when compared to mills of similar shell dimensions in gold mining, treating similar ore. This paper describes the systematic improvement of the SAG circuit to its current state.

Jan 1, 2012

By Clifford R. Stanley

"Abstract - Reproducible analyses of representative samples for elements affected by the ‘nugget effect’ is vital in mineral exploration and reserve estimation. Unfortunately, a priori knowledge of what size of sample is representative from a mineral deposit or its dispersion train is commonly unavailable. Use of the simple ‘equant grain model’ and the NUGGET computer program facilitates determination of the sampling parameters that will produce appropriate samples for chemical analysis. Based on Poisson statistics, NUGGET can be used to determine: (1) the ‘effective grain size’ of nuggets in a suite of samples, (2) the level of representativity (precision) that samples with specific nugget grain sizes will exhibit, and (3) the sample size required to obtain a specific level of sample representativity. The program determines these sampling parameters for any element in any mineral, including solid solution minerals (e.g., Au, electrum, Pt-Fe alloy, diamond), and allows assumption of a variety of grain shapes (e.g., ellipsoids, cylinders, parallelepipeds, etc.). Furthermore, it outputs the effective number of nuggets expected in a sample of given size and the percentile confidence bounds on any element concentration affected by the nugget effect.Results from the software allow determination of effective sampling and analysis strategies that minimize the nugget effect in geochemical analysis/assaying used in mineral exploration and reserve estimation. This will not only improve confidence in the resulting exploration results or reserve estimate, but will facilitate estimation of the error associated with any subsequent interpretation or reserve figure."

Jan 1, 1998

The reliability of mining systems is generally low due to their harsh working conditions. Currently, efforts for improving mining system reliability are often made in isolation. This practice could substantially limit the effectiveness of the efforts on overall reliability improvement of the mining system. To enhance the overall reliability of mining systems, an integrated improvement approach is necessary. In this paper, we developed a framework for integrated mining system reliability improvement to address this issue. In this framework, there are five major components including data integration, business process integration, hardware integration, software integration, and analysis/decision integration, but we only focus on the integrated reliability analysis which is important to the analysis/decision integration. The reliability analysis considers the interactions between machines, and the impacts of design, operation, maintenance, automation and working environment on the overall system reliability. These multiple interactions present a big challenge to accurate reliability prediction. In this paper, we for the first time systematically investigated integrated reliability analysis approaches for dealing with this challenge using novel models and methods, including covariate hazard models, intelligent reliability prediction approach, and complex system modeling methods. While these models and methods have found some successful applications in other industries, they in general have not been effectively used for the reliability analysis of mining systems. Our study results show that the system integration approach is applicable to mining systems and can be used for developing a computer aided integration system for the implementation of the integrated reliability improvement approach.

Aug 1, 2013

By Gary Walters, Thomas Gonzales, David George, William Davenport, Andreas Siegmund, Suping Yao, Shijie Wang

The previous survey of world copper smelters was in 2016 (Copper, 2016). The copper smelting industry has grown and improved considerably since then, including continuing growth in China and modernization in Japan (Extraction, 2018). Outotec flash smelting and Outotec flash smelting/Kennecott - Outotec flash converting continue to be adopted while newer processes continue to be adopted in China. In addition, some of the world's original flash furnaces have been completely rebuilt (Extraction, 2018). This paper provides recent industrial production data and discusses these new developments. INTRODUCTION A world copper survey was redone in 2016 after a thirteen year lag since 2003. Some of the notable changes were the significant increases in production particularly from China. Since then, several smelters have gone through modernization processes and decommissioning of older technologies. This paper will review the notable changes since the last publication at Cu2016. In the last paper, Copper Smelting: 2016 World Copper Smelter Data, the author gave an audible sigh after observing that copper smelter sites as well as new and notable smelters have been spreading like wildfire in China since 2003. Indeed, seeing is believing. Figure 1 shows the Ningde Copper Smelter (double flashing, 400,000 MT Cu/Year capacity) that started up producing copper in 2018; Figure 2 shows the Nanguo Copper Smelter that is under construction with 300,000 MT Cu/Year capacity (first phase, side blown smelting and continuous top blown converting). We should not only admire the Chinese copper industry’s significant technological developments, but also the copper price support that it has provided throughout this century.

Jan 1, 2019

By C. Okay Aksoy

In Turkey, the increasing demand for lignite has necessitated an increased emphasis on both lignite production and recovery. This emphasis has resulted in a gradual increase in the application of the retreat longwall mining method for both its product recovery and productivity benefits. Also, in order to maximize the recovery of the natural resources and to increase total production, it is necessary to take advantage of underground reserve before abandoning the mine. This means that at the end of the life of the mine, the main drift safety pillar and the shaft pillar will generally be extracted. This investigation a preliminary study of the stability of the main drift and the shaft at the Hustas Mine as the safety pillars are extracted. In this study, field surveys belonging to the underground colliery of Hustas Co. in Soma have been investigated with the help of LAMODEL working under the Laminated Displacement Discontinuity principle for the models calibrated as a results of physical model and finite element analyses. The convenience of Laminated Displacement Discontinuity Analysis has been researched in such studies. The results out of the models have been coherent with the previous studies.

May 1, 2004

By J. Bhattacharya, S. K. Mukhopadhyay, S. K. Pal

"While time and again many authors have categorically stressed the restoration of the environment, very little effort has been made in the mineral industry to develop the economy of environmental control. There are many abatement procedures that search a maze of variants. Among them pricing environmental damage seems to be more logical and easily implementable.IntroductionMining as an operation has a severe impact on the Earth's natural resources. While economical environment control is much sought after, solutions are often varied and complex, and can differ in the problems of single or multiple mine sites.Determination of Optimum use LevelsIn “mining environmental control"" it is required to strike a balance to find optimum use levels. The solution is to find where the welfare benefits equal the cost involved to curb the degree of environmental damage (Fig . I) . In the mining industries this can be done by modifying the production/extraction process itself. For most pollutants, the marginal costs of control will exceed the benefits from further reduction of damage long before the zero pollution damage point is reached (Fig. I). From an economic perspective the optimal alteration of environment by mining would occur at z; pollution continues to be caused by ""zy"" control units, but it would be inefficient to pursue the redemption efforts further because the marginal cost involved would exceed marginal welfare benefits."

Jan 1, 1992