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By Mike O'Shea

Industrial minerals are extremely important to downstream industries and in our everyday lives. Their ontribution to the UK economy and to society as a whole is greatly underestimated. The industrial minerals sector is lacing increased pressures - environmental and competitive - both at home and abroad. These pressures are likely to increase. The Government, working in conjunction with the industry, can help the industry to meet these challenges. The role of Government is to establish a dialogue w ith the industry, to find out what its concerns are.and to ensure that these are taken into account in the draw ing up of policies that affect it. There is also a role for it in exploring, with industry, the linkages between environmental improvement and competitive advantage, and giving, w herever possible, early warning about regulatory developments. In order to maximise the effectiveness of links, industry needs to be coherently organised and represented both in the UK and in the European Union (EU).

Jan 12, 1997

By Brad Simser

Several case histories from Glencore’s Sudbury Operations show how passive seismic monitoring data is used for geotechnical decision making. The data comes from three different seismic arrays monitoring two open stoping deposits, and a narrow vein cut and fill/blasthole operation. Mining depths range between 1000 to 1680m below surface. The deposits are hosted in hard igneous rocks typical of the Sudbury basin, with characteristically high horizontal stress (approximately 1.8 times the depth of overburden). Rockbursting is the main geotechnical risk, due to the strong brittle nature of the rock and local high mining extraction. Fault related seismicity includes both fault slip events, and the stress channelling effect as the mining front approaches a major fault structure. Planar data trends generally line up with known faults and often indicate early stage fault activation. The structures are risk ranked based on their seismic response. This has been particularly useful at the Nickel Rim South Mine (NRS) where the structural fabric (jointing and small-scale faulting) is generally parallel to the more through going faults. The persistence of structures is difficult to measure, and the NRS faults generally have low offsets and thin gouge. The visual difference between the more persistent structures that occasionally generate large seismic events (up Mw 2.9 to date) and localised joints/slips is often minor. The seismic monitoring data clearly shows the more active structures. This information is highlighted on mine plans to help guide enhanced ground support and seismic re-entry protocol barricade locations. Pillar loading/yielding is a key element to the blasthole operations where a primary/secondary mining sequence is used. The secondary pillars are mined in a yielded state with just-in-time development. An example of the seismic signature of a secondary stope is shown with emphasis on the need for high location accuracy given the stope widths of 12.5 to 15m. The ratio of the shear wave energy to primary wave energy (Es/Ep) has long been used as a method to estimate source mechanisms; the higher the ratio, the more likely the event is fault slip versus rock fracturing. Data sets are filtered on Es/Ep ratios to highlight both fault slip populations and stress fracturing mechanisms. Examples of seismic data quality checks, high stress development, and re-entry protocols are also shown in the case histories.

Apr 26, 2022

By III Feeley

The U.S. Department of Energy is supporting the engineering development of three advanced physical coal cleaning technologies--selective agglomeration, advanced flotation, and advanced cycloning--capable of significantly reducing the pyritic-sulfur content of U. S. coals. The objective of this activity is to provide the coal production and electric-utility industries with a cost-effective option for addressing the SO2 emission reductions required by the 1990 Clean Air Act Amendments. A secondary objective is to evaluate the potential of advanced coal cleaning for removing trace elements that are precursors to the formation of hazardous air pollutants. This paper will summarize the status of the three advanced physical coal cleaning engineering development projects.

Jan 1, 1993

By J. Villeneuve

Steady-state simulation has proved to be a very useful aid in designing new plants and optimizing existing ones. The algorithms and data definitions of existing simulators often, however, require a great deal of expertise for implementing a simulation-based methodology. The constraints imposed by conventional simulators are explained and the advantages of a new algorithm, the Objective-Driven Simulation, are shown. These advantages are a) an improvement in the simulation results, which enables simplifications of the methodologies used, and b) the possibility of taking into account economic objectives for plant operation, thus extending the range of application of steady-state simulation.

Jan 1, 1992

By George H. Davis

Much concern has been expressed recently as to whether water supplies will be sufficient to support accelerated energy development foreseen in operation Independence. Taking the Nation as a whole, sufficient water is available for energy growth, but locally, as in arid parts of the Colorado Basin, limited water supplies will dictate economies in water use and affect plant siting. As Young and Thompson1 point out with respect to electric power generation, the term "water requirements" is misleading, as demand for water for cooling is sensitive to price of water and thus is quite flexible rather than the inflexible or fixed level implied by the word "requirement." Much the same is true of other energy conversion systems. Water is used in many aspects of energy production including mining and reclamation of mined lands, on-site processing, transportation, refining, and conversion to other forms of energy. In the East, South, Midwest, and along the seacoasts, water supplies are generally adequate for energy industries; most water problems in those regions relate to pollution rather than supply. West of about the 100th meridian, however, runoff is generally less than potential diversions and energy industries must compete with alternative uses for the limited available water supplies. Water is especially short in areas of less than 10 inches mean annual rainfall where natural precipitation generally is insufficient for establishing vegetation without irrigation. Extraction. The principal categories of extraction comprise coal mining, oil and gas production, uranium mining, and oil shale mining.

Jan 1, 1974

By S. Razavialavi

In the planning phase of every construction project, layout of temporary facilities is a crucial task; site layout can affect safety, travel cost and time, construction productivity, and space utilization. However, site layout planning can be a complicated problem, due to the interdependency of influencing factors. Although interaction among activities is one of the major drivers of site layout planning, it has not been properly addressed in past research. In this study, simulation is presented as a promising tool to address this gap. The capability of simulation technology to model complex processes in construction projects makes use of simulation tools in site layout optimization problems effective, while existing methods are unable to perfectly model these problems, in some cases. Additionally, the advantages and challenges of implementing simulation are assessed and a generic framework for simulation application in site layout planning is proposed.

Aug 1, 2013

By R. Benemelis

The existence of resins in some coal deposits in various parts of the world has been known for many years. These resins vary considerably in chemical structure and properties. The resin that is found in Utah coal, however, is rather unique, and has properties particularly attractive for the manufacture of printing ink mastics and adhesives. This resin is a rather dark, very high melting point, low molecular weight hydrocarbon resin. Its typical properties are shown in Table I. Its largest use by far, has been in the printing ink industry. The history of Utah coal resin is interesting, but unfortunately one of disappointment and failure.

Jan 1, 1990

By D Prior

The Australian mining industry is a significant contributor to the nation’s greenhouse gas (GHG) emissions, and like any industry, it must make efforts to reduce these. Medium- and long-term strategies will include the replacement of diesel engines with alternative energy sources, but what can be done in the short-term to reduce diesel consumption and hence CO2 emissions? Haul trucks are identified as the major contributors of CO2 emissions in the mining fleet and this paper focuses on firstly identifying what drives haul truck emissions and secondly, discussing what is the role of the Fleet Management System (FMS) in reducing these. A key enabler of this is having a robust fuel consumption model within the FMS, and I describe how this may be done. Besides novel approaches to incorporating fuel consumption (CO2) management into truck assignment algorithms, this paper also describes how the FMS can be used to implement and manage procedures and policies to reduce haul truck emissions.

Jun 22, 2022

By Julian Malnic

Various natural, commercial, engineering and operational factors govern the evolution of approaches taken in the exploration for Seafloor Massive Sulphides (SMS) and in delineating the resource. These stages are prerequisites to the proposed mining of SMS deposits. This paper presents and analyses these factors from the view of an SMS exploration company that is pioneering the exploration of this rich alternative source of zinc, copper and gold. Current exploration practices developed by Marine Scientific Research (MSR) workers for SMS deposits are expected to give way to industry-generated methods as the SMS exploration industry gathers momentum. The exploration process falls into three phases that are described below: Prospecting (locating targets), Indicating Resources, and Measuring Mineral Resources Considerable streamlining of the SMS exploration process will accelerate the rate of discovery. The economics of SMS mining are projected to be superior to comparable terrestrial mining operations in both operating cash cost and capital terms.

Jan 1, 2001

By W. K. Choi

Using electrochemical techniques it was demonstrated that bioleaching of gold from refractory pyritic ores is a complex phenomenon. Many intermediate electrochemical reactions were found to be involved in the oxidation of pyrite, using cyclic voltammetry and carbon paste-pyrite containing electrode. Furthermore, the oxidation process was controlled by solid-state diffusion as suggested by chronoamperometric and chronopotentiometric measurements. Using the Sand's approach, the activation energy of solid-state diffusion was found to be = 22.4 kJ. After bioleaching, 96% gold was extracted from the leach resi¬due with a thiourea solution in 1 hour. A generalized model for the mechanism of pyrite oxidation has been presented.

Jan 1, 1990

By David Bequette, Ray D. Peterson, Cynthia K. Belt

"With a need to cut production costs in the metals industry, cost savings from energy efficiency improvements are critical. Opportunities can be found by reviewing furnace systems and practices so that the melting and holding processes operate at the highest energy efficiency. Many of the changes can be implemented with a minimum of expense or capital investment. This paper will review several low cost methods to optimize energy efficiency on reverberatory melting or holding furnaces. These five methods (furnace utilization, idle procedures, fire rate, controls, furnace pressure) will be explained and information given to implement these changes. Included are several rules-of-thumb and benchmarks for aluminum reverb furnaces.IntroductionEnergy can be a significant portion of the total manufacturing costs for metals and materials manufacturing involving thermal processing such as heat treating, melting, and high temperature processing. Natural gas prices have dramatically varied over the last few years. While no one can foresee the future, prices are expected to increase from the current low prices. More recently, emphasis is being put on the reduction of greenhouse gases with the potential of additional costs to industry.One of the first steps in an energy management program is to measure the energy usage of the process [1]. The results are typically understood in relation to the mass melted in kWh / mT [BTU / lb]. For the purposes of this paper, furnace energy efficiency is calculated over a month or even a year and thus includes hold times. This efficiency is typically different from the values quoted by furnace manufacturers. Those values are for limited short term tests at highutilization.Once you know the performance for your furnaces, these should be compared to industry benchmarks. For aluminum melt furnaces with cold air burner systems, a benchmark value or goal is 1800-2000 BTU/lb [1160-1290 kWh/mt], though some of the best have reached 1600 BTU/lb [1030 kWh/mt]. Furnaces with regenerative burners can attain 1100-1200 BTU/lb [710- 775 kWh/mt]. There are some designs of multi-chamber furnaces or oxygen furnaces that have improved on these numbers, perhaps as low as 950 BTU/lb [615 kWh/mt]. Typically, as the degree of sophistication and energy efficiency of the furnace increases, so does the cost."

Jan 1, 2010

By Sumit Kumar Hota, Asadi Srinivasa Reddy, Ashok Kumar, Ashish Agrawal, Surajit Sinha, Chandra Sekhar, Tanay Ray

In the current operational facility, due to the absence of pellet pot facility, a novel technique is developed wherein the pellets with different chemistries prepared in the laboratory are fired in an induration machine by placing them inside the Inconel baskets. In the present work, an attempt is made to optimize the pellet chemistry by developing 2 different flux pellets, viz., low basicity (B2: CaO/ SiO2 = 0.3) pellets and high basicity (B2 = 0.9) pellets, and further the effects of basicity on pellet properties, viz., cold compressive strength, porosity, swelling index, reducibility index, and softening and melting temperature, are studied. It has been found through the multiple operational trials that increasing the basicity of pellets from 0.3 to 0.9 results into improving the pellet strength, reducibility and softening and melting characteristics. Moreover, it is observed that the swelling index of pellets is reduced by adding 2% MgO to both low and high basicity pellets that could be attributed to the formation of high melting point slag in pellets. The operational trial has resulted into producing pellets that exhibit a combination of desired mechanical strength, improved swelling, and reducibility index and possess better softening–melting behavior among all the chemistries studied.

May 24, 2022

By Nasib Al Habib, Hooman Askari-Nasab, EUGENE BEN-AWUAH

In-pit crushing and conveying (IPCC) is getting popular in deeper open pit mines as a suitable alternative to truck haulage because it offers a lower operating cost due to shorter haulage distance and less truck requirement. Semi-mobile in-pit crusher, currently the most popular IPCC system, is relocated every two to five years, and the short-term plan needs to be updated accordingly. To the best of our knowledge, short-term planning with IPCC is an area of research that has yet to be explored extensively, and hardly any model can generate a shortterm extraction sequence considering an IPCC. This research work proposes a mixed integer programming model to develop a short-term production plan within a time horizon of 12 months. The model's objective is to optimally allocate shovels to minimize the cost of material handling and maximize revenue subject to meeting plant requirements, maximum allowable tonnage variation and IPCC location constraints to achieve production and NPV targets set by the strategic plan. The proposed model will be implemented in an iron ore mine case study for verification. The model is developed and solved using MATLAB. The comparison of results between scenarios with and without IPCC justifies the use of IPCC in large open pit mines from a short-term perspective.

Jun 25, 2023

By E. Siami-Irdemoosa, S. R. Dindarloo

"Pareto analysis was used to investigate the failures database of a Hitachi EX1900 hydraulic shovel over one year of continuous operation. The hydraulic system and hydraulic links, hoses and piping were identified as the most critical system and subsystem, respectively. A three-parameter gamma distribution function was identified as the best fit for a probabilistic modeling of the time between failures (TBFs). This distribution was used in a Monte Carlo reliability analysis of the hydraulic system. Autoregressive integrated moving average (ARIMA), within the context of a time series analysis of the TBFs, was proposed as a viable alternative to the traditional technique of distribution fitting. The mean absolute percentage error (MAPE) metric was used to compare the two models. The MAPE value that resulted from the ARIMA was 66 percent smaller than that from the traditional technique in predicting the TBFs. Resumen ¦ Se usó análisis Pareto para investigar la base de datos de fallas de una pala hidráulica Hitachi EX1900 durante un periodo de un año de operación continua. Se identificó al sistema hidráulico y a los enlaces hidráulicos, mangueras y tuberías como el sistema y subsistema más importantes, respectivamente. Se identificó una función de distribución de tres parámetros gamma como el más apto para un modelado de probabilidades del tiempo transcurrido entre las fallas (Tabes por sus siglas en inglés). Esta distribución fue usada en un análisis de confiabilidad Monte Carlo para un sistema hidráulico. El promedio de movimiento integrado auto-regresivo (ARIMA por sus siglas en inglés), dentro del contexto de análisis de serie temporal de los TBFs, fue propuesto como una alternativa viable a la tradicional técnica de ajuste de distribución. Se usó el porcentaje de la media absoluta de error (MAPE) para comparar los dos modelos. El valor MAPE que resultó de la ARIMA fue 66 por ciento menor que el resultado obtenido con la técnica tradicional de predicción de TBFs."

Jan 1, 2015

By L. M. Guayacán-Carrillo, G. Armand, A. Noiret, D. Seyedi, S. Ghabezloo, J. Sulem

"The main purpose of this paper is to analyze the convergence measurements in a drift excavated in the Callovo-Oxfordian claystone. The drift axis is in the direction of the major principal horizontal stress whereas the stress state is quasi-isotropic in the drift’s section. The initial geometry of the drift being circular, the anisotropic character of the deformation is taken into account by assuming that the drift shape evolves in an elliptical shape. The convergence measurement data on six different points around the drift are analyzed to identify the main axes of the deformation ellipse, following the methodology proposed by Vu et al. (2013, Rock Mech Rock Eng, 46, 231-246). Then, using the semi-empirical law proposed by Sulem et al. (1987, Int J Rock Mech Min Sci, 24, 145–154), the convergence evolution is fitted independently for each axis of the ellipse. This method permits to distinguish two effects: the face advance effect and the time-dependent behavior of the ground. The results for the two directions of the ellipse axes show very close values for the parameters describing the time-dependent properties of the ground, the distance of influence of the face, and the extension of the decompressed zone around the gallery. Such model can provide valuable insights for predictions of the convergence evolution in the long-term. INTRODUCTIONDeep disposal of radioactive waste has been studied in France for more than two decades. The French National Radioactive Waste Management Agency (Andra) began in 2000 the construction of an Underground Research Laboratory (URL) with the main goal of demonstrating the feasibility of a geological repository in Callovo-Oxfordian claystone. Several research programs have taken place to improve the knowledge of the rock properties and its response to the excavation progress. The optimization of supports design for long-term behavior is an important point to develop. A network of experimental drifts has been constructed with variations on: excavation method, structure geometry, supports system and orientations with respect to in-situ principal stresses’ directions. In each drift different sections have been instrumented to monitor the convergence evolution and the rock deformation. Continuous monitoring of the excavated zone around the drifts revealed the development of a fractured zone (extensional and shear fractures) induced by the excavation. The extent of this fractured zone depends on both the drift orientation and the in-situ stress field (Armand et al., 2014). Indeed, the fractures distribution has an important influence on the convergence of the drifts."

Jan 1, 2015

By M D. Uttarwar, R R. Yerpude

India is the world’s third-largest producer of coal and is endowed with the fifth-largest coal reserves in the world. Surface mining straddles the entire domain of the Indian coal mining industry, yielding over 88 per cent of production. With continually rising domestic demands, it has to shoulder the responsibility of sustaining the requisite increase in coal production and chasing commensurate stripping targets. Such an ambitious task calls for the deployment of smart technologies. In such a demanding situation, cast blasting of overburden has emerged as a promising alternative for enhancing production and productivity of dragline pits.The cast blasting technique reduces stripping costs significantly as it utilises the chemical energy of explosives in place of mechanical energy to move large volumes of overburden quickly. Proper application of cast blasting not only reduces overall mining costs but also increases coal production. This paper investigates and evaluates the potential of the cast blasting technique, with special reference to dragline pits employing the rehandle method of extended bench. The economic feasibility of the technique is also ensured under different scenarios so that considerable benefits would accrue to the individual surface coalmines. To underline the efficacy of the technique, different cast blasting models have been formulated under a range of operational and economic scenarios that resemble present day practices in India. In order to test for economic variability in the application of the technique, a risk analysis of all the formulated cast blasting models is performed using net present value.CITATION:Uttarwar, M D and Yerpude, R R, 2015. Potential of the overburden cast blasting technique in Indian surface coalmines – a modular approach and its financial implications, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 655–664 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By C. W. Smith

Research was conducted to evaluate the effectiveness of a well-point dewatering system in conjunction with a french drain to intercept waste impoundment leakage while reducing the volume of waste water requiring treatment. A well-point dewatering system composed of 585 production wells was installed around the perimeter of a leaking impoundment that previously used only a french-drain system for leakage control. The placement of the well-point system was designed to intercept and remove the leakage from the groundwater before the contaminant reached the french drain. Groundwater monitoring at this site revealed that after a period of approximately 40 days the well-point dewatering system had stabilized and effectively prevented the further spread of contamination to the french drain.

Jan 1, 2010

The first metal-mine accident-prevention course was prepared and published in 1942-45 as a series of seven miners' circulars (Nos. 51-57). The scope of the course has been broadened, revised, and brought up to date, and it is being published as a similar series of seven miners' circulars (Nos. 51-57, revised) on accident prevention in metal and nonmetallic mines. These circulars are: Accident Statistics (Miners' Circular 51), dealing with general statistics on accidents and injuries at metal and nonmetallic mines, including causes, costs, and the uses of investigations and reports of all accidents.

Jan 1, 1955

By F. T. M. White, W. A. Bardswick

"The parameters of airborne minerallic particulates which create industrial dustiness, together with the physiological hazards caused by their inhalation, are reviewed. Various techniques of dust sampling are discussed and analysed, and the parameters referred to above are classified as the basis for methods of assessing the physical, chemical and mineralogical characteristics of dust-particle suspensions. The paper surveys those methods of assessment currently accepted by various statutory authorities, and reviews other methods that warrant attention and newer techniques that are being developed."

Jan 1, 1969

By J. H. Gasper

A cost analysis for two alternative contour mining methods is performed to compare their results. The methods evaluated are: 1) Front-End Loader/Truck Haulback and 2) Scraper Haulback. Before performing these analyses, output requirements and equipment needs are found based on integrating geometric limitations with material properties. The final geometric design establishes limits on clearances, congestion problems and grades (with associated running surface materials). All calculations are kept practical, with assumptions clearly stated. The cost analysis is a unique, easily utilized compilation of several different approaches incorporating cost engineering principles. The strengths of each are welded into a cohesive entity once again aimed at practical application. The results are presented in tabular form.

Jan 1, 1992