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By J. Saunders, N. Pretorius, G. Krafft, T. P. Katakwa

Imagine being able to see all the future planned mining activities in real time. This is exactly what SIMS (Short Interval Management System) will enable you to do. SIMS is a real time short interval control system that continuously measures and sets optimised plans for mining production processes. The system utilises algorithm-based software that takes resources (people, equipment, tasks, and workplaces) and gives you the best achievable plan. The algorithm was developed using methods found in the field of metaheuristics. A metaheuristic is a strategy to designed to efficiently search for optimal or near optimal solutions to problems that are very complex computationally. (Glover, 1986) There are several algorithms that have been developed to solve optimisation problems which are difficult to solve using traditional techniques. This has given rise to a field called evolutionary computing. (Simon, 2013) Examples of these techniques are genetic algorithms, particle swarm optimisation, and ant colony optimisation. These methods are used to solve problems in a variety of fields. As an example, Kok and Lane (2012) used particle swarm optimisation for equipment allocation in a mechanised underground mining environment. The first SIMS deployment took place in a platinum underground tabular mechanised mine near Burgersfort (province?) from 2017-2019. This included the development from a paper-based system to a fully operational online system. SIMS then moved to a second site and is currently being tested in a second platinum underground tabular mechanised mine in South Africa. Full deployment of the system is currently being phased in. SIMS was built in response to issues that have been plaguing the mining industry for years. These issues are all aligned into one major problem statement: how can we optimise mining production processes without compromising safety? This product was developed by combining years of mining experience with software development. SIMS is based on a four-pillar concept. Safety, productivity, accountability, and business improvement. SIMS uses a set of pre-configured mining and production rules, and with the resources that are available, to determine valid short term production plans. A background algorithm then determines the optimum plan to be executed. The system continuously produces a set of job cards that are pushed to respective operators on their allocated tablets. The management portal component allows you to view and manage all current and planned work on any connected device available. This allows real time visibility of completed, current, and planned work to operators, service departments and management, i.e., seeing into the future.

Sep 1, 2021

By M. J. Zdunczyk

Located approximately 50 miles northeast of Knoxville, Tennessee, Short Mountain Silica mines the Clinch Formation, an orthoquarzite, for silica sand. In 1980, a Knoxville resident and area contractor visualized mining Short Mountain for silica sand. Because APG Industries, the main market for the glass sand product, was only 48 kilometers from the site, many silica sand companies became interested in the property. In 1986, J.D. Nicewonder began to develop the site, and in May of 1988, APG Industries received the first sand shipment.

Jan 1, 1992

By Matthew Burdick, Andrew Rule, Erica Bailey

The Second Narrows Water Supply Tunnel, Burrard Inlet Crossing project for the Greater Vancouver Water District entails deep shaft construction, subway sized pressurized face tunneling through highly variable ground conditions, installation of three permanent steel water mains and construction of elaborate valve chambers adjacent to either shaft. The paper discusses key elements of the planning and implementation of 6.69 m Ø slurry mixshield tunnel boring machine (TBM) assembly in a small diameter deep shaft including incorporation of a fully pressurized launch lock, preparations for saturation diving, surface support infrastructure and initial mining sequence.

Jun 13, 2021

The Mesquite mine is being operated by Gold Fields Operating Co.-Mesquite, a subsidiary of Gold Fields Mining Corp. The mine Is located in southeastern California about 56 km (35 miles) east of the farming community of Brawley, California. The mine has been in commercial production since early 1986 and Is a conventional open pit mine developed on 6.1 m (20 foot) benches. The gold is recovered by heap leach using permanent heaps built in multiple 6.1 m (20 foot) lifts. This year's gold production will be in the range of 5,600 kg (180,000 troy ounces). Current ore production is about 18,140 tonnes (20,000 tons) per day while the total tons mined Is averaging 65,000 tonnes (72,000 tons) per day. The climate at the mine is extremely arid with rainfall of 7.6 cm (3 inches) per year. From early May until late October daytime temperatures generally exceed 37.8 degrees Celsius (100 degrees Fahrenheit) and can be as high as 37.9 degrees Celsius (120 degrees Fahrenheit).

Jan 1, 1989

By R. W. Barbaro

The limitation of sulfur dioxide in power plant emissions dictates that sulfur in coal be reduced to the lowest possible level before combustion so as not to aggravate the emission control problem at the stack. For coal fired power plants, the methods in practice to achieve low sulfur coal include mining areas with relatively low sulfur. reducing sulfur in the mined coal through preparation techniques and blending high and low sulfur coals. A prerequisite to the successful implementation of any of these practices is the knowledge of the spatial distribution and the capability to predict sulfur values in a coal seam.

Jan 1, 1988

By Michael Gilbert

In the world of tunneling the glamour is in the large diameter, long tunnels, but perhaps the number of projects for small diameter and short length tunnels are greater and generally have higher risk factors. Reasons for these higher risks include both the ?boiler plate? contract provisions used on these types of contracts, the technical specifications related to the tunnel work (versus the pipeline construction), the bid practices including measurement and payment and the construction. This paper reviews and comments on some of the key issues the authors have observed in recent major pipe-line projects that involve a small percentage of tunneling footage of the total contract.

By David Smith

Construction of a new transportation link frequently requires crossing under an existing highway or railroad. Although traffic diversions may permit a cut and cover structure to be built, ‘zero impact’ tunnel solutions are becoming increasingly popular. The vertical clearance between the new tunnel structure and the existing highway or tracks may be very low; sometimes less than two meters. This leaves little room for error since any ground loss can rapidly translate into surface settlement. Problems can be avoided by maintaining the stability of the tunnel face and by minimizing ground movement around the tunnel lining. This paper examines construction methods that have been used to construct short tunnels with shallow cover, and highlights factors to be considered for future projects.

Jan 1, 2005

By S. V. Lukichev, O. V. Nagovitsyn, V. V. Laptev

In this paper the authors describe the developed algorithms of short- and medium-term planning of underground mining operations. The algorithms were developed using the example of the flat-back cut-and-fill method, and provide multifactor accounting of mining conditions, technical and technological limitations: state and properties of the rock mass; the current mining situation; mining rules; availability of safety pillars; properties of the filling; additional characteristics of technological objects that complicate the driving of workings; sufficiency of human and technical resources; employee specialisation; existing machinery and equipment; opportunities and limitations of the transport scheme of the mine, and work schedule. The paper is presented by means of a dynamic model of mining development, which shows the sequence of mining operations in the mine workings. Besides animation, the tool provides an opportunity to form tabular and graphical reports.

Sep 1, 2021

By Lewis L. Oriard

The authors outline the development and application of blasting methods put into use 11 years ago at the Berkeley Open-Pit Mine, Butte, Montana. The blast design uses a very short delay (5 milliseconds) between detonation of explosives charges, a feature challenged several times in principle despite its success for Anaconda. Concern is expressed over the categorical rejection of very short delay blasting which can make the difference between success and failure of major mining operations. There is ample evidence to show that the method can be used successfully and not violate the concerns of the public.

Jan 1, 1980

By Stephen C. Tadolini, Steve Bessinger, James Pile, Christopher Mark

The San Juan Coal Mine, located near Farmington, New Mexico, supplies the San Juan Generating Station with more than 6 million tons of coal annually. To replace dwindling surface mine production, San Juan installed a longwall in 2002. The roof rock in much of the underground reserve consists of interbedded coals, carbonaceous shales, and mudstones. Roof support consists of fully-grouted roof bolts, both tensioned and non-tensioned, supplemented by modified cable trusses. Short-encapsulation pull tests conducted by San Juan’s geotechnical engineering department showed that some of the immediate roof layers provided variable bolt anchorage. To ensure that the roof bolts were obtaining the necessary anchorage, additional tests were conducted in a variety of locations. The results have been used to determine the optimum support design for different areas of the mine. Another series of tests evaluated the performance of several bolt and hole diameter combinations. The experience at San Juan Mine shows that short-encapsulation pull tests can provide the information necessary to improve ground control in variable roof conditions. It also illustrates how a pro-active geotechnical engineering program can be an essential component of a state of the art underground coal mine.

By James Pile

The San Juan Coal Mine, located near Farmington, New Mexico, supplies the San Juan Generating Station with more than 6 million tons of coal annually. To replace dwindling surface mine production, San Juan installed a longwall in 2002. The roof rock in much of the underground reserve consists of interbedded coals, carbonaceous shales, and mudstones. Roof support consists of fully-grouted roof bolts, both tensioned and non-tensioned, supplemented by modified cable trusses. Short-encapsulation pull tests conducted by San Juan's geotechnical engineering department showed that some of the immediate roof layers provided variable bolt anchorage. To ensure that the roof bolts were obtaining the necessary anchorage, additional tests were conducted in a variety of locations. The results have been used to determine the optimum support design for different areas of the mine. Another series of tests evaluated the performance of several bolt and hole diameter combinations. The experience at San Juan Mine shows that short-encapsulation pull tests can provide the information necessary to improve ground control in variable roof conditions. It also illustrates how a pro¬active geotechnical engineering program can be an essential component of a state of the art underground coal mine.

Jan 1, 2003

By B. M. Flohr

Railroads are cost competitive with trucks for hauls greater than 500 miles - WRONG. Today I will tell you about many rail movements of less than 100 miles throughout the country. Rail is a short haul transportation alternative you must consider. Transportation today is the largest controllable cost in the total cost of production of goods. In fact it is the one cost area where aggressive management, using new tools, can achieve significant reductions. You can't control the price of metals in the world market, you can't control labor rates since they are tied to industry norms, and the price of raw materials are relatively insensitive to specific price reductions to your firm. Transportation is the one area where major savings are now being realized. Sample Movements First, I will give you several examples of short haul rail moves to make you a believer that they do exist. Then I will show you the reasons why railroads suddenly "like" short hauls.

Jan 1, 1986

By B.E. Hall

Maximizing shareholder value has become a common aim for mining companies. This paper discusses the results of a number of studies developing strategic mine plans, covering a wide range of commodities, styles of mineralization, mining methods, and processing facilities, for single and multiple deposits. It has become evident that traditional methods and conventional wisdom often do not in fact achieve these goals. Operating policies at many mines ensure that shareholder value is not maximized. Changing the overall strategy can provide significant value gains. Typically, the new optimal plan involves a significant increase in the cutoff grade, at least in the earlier years. An increase in the underground development rate or open cut stripping rate is often associated with this, at least in the short term, to establish the new strategy. Cost minimization is found to be counter-productive. Counter-intuitive plans are often found to be optimal. For example, optimal cutoffs for different parts of an underground mine may be significantly different, even if mineralisation and cost structures are similar. Sub-optimal strategies are also frequently found to have a significantly greater financial risk than optimal plans, which have been found in many cases to be relatively insensitive to changes in major value drivers, such as metal prices. This paper shows how identifying and then operating within the framework of an optimal strategic plan can have substantial benefits over being continually driven by short-term tactical issues.

Jan 1, 2009

To pinpoint dust sources and to improve dust control on longwalls. Approach Use short-term gravimetric sampling to determine the severity of various dust sources, and to evaluate dust control techniques used in longwall mining. Short-term gravimetric sampling can be used to isolate dust levels produced by various dust sources. How It Works Traditionally, gravimetric samples have been collected over an 8-hour shift, yielding time-weighted, average dust concentrations. This method gives a good indication of the full-shift respirable dust exposure of underground workers, but is less than satisfactory for identifying dust sources, determining their severity, or for evaluating the effectiveness of dust control techniques. Short-term gravimetric sampling uses equipment available to all mine operators. Two individuals composing the survey team each collect multiple (three to four) gravimetric samples during selected segments of the mining cycle. Multiple samples are necessary to insure accuracy, and to obtain a valid average measurement of the respirable dust concentration when sampling for short periods of time (typically 20 to 30 minutes). The gravimetric instruments may be carried in a sampling package or in a "sampling vest." A fishing vest with four large pockets can be used for this purpose. The sampling pumps are carried in pockets and the sampling head assemblies arc hung across the front of the vest.

Jan 1, 1982

By E. Ben-Awuah, H. Askari-Nasab, N. Al Habib

Open pit mines are getting deeper with time and transportation expenses are increasing because of the increasing haulage distance. 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. Short-term planning with IPCC is an area of research that has not been explored extensively yet and hardly any model can generate short-term extraction sequence considering an IPCC in place. This research work proposes a mixed integer programming model to generate short-term production plan within a time horizon of 12 months. The objective of the model is to optimally allocate shovels to minimize cost of material handling and maximize revenue subject to meeting plant requirement, maximum allowable tonnage variation and IPCC location constraints to achieve production and NPV targets set by strategic plan. The proposed model has been implemented in a hypothetical case study for verification. The comparison of results between scenarios with and without IPCC is expected to justify the use of IPCC in large open pit mines from a short to medium term perspective. A semi-mobile IPCC system with one relocation is considered in the case study.

Feb 1, 2023

By B. Arlyuk

On the basis of research of relations among the market participants the analytical model has been created which connects the price of industrial good at stock exchange with volume of sales and the stock of the sellers and buyers, Also a model was developed for assessment of these parameters of the market status by the actually fixed stock exchange and general market indicators. The composition of these models made it possible to create reliable system of short-term price forecasting for commodities or base metals up to one quarter ahead. Imperfectability of creation a model for reliable price forecasting by purely statistic methods (by the "black box" principle) was shown. A model of price behavior qualitative forecasting till one quarter ahead has been developed, which determines the probability of reaching in future of the given level as well as of the price maximums and minimums, Optimal values of threshold probability were determined for forecasting the future price maximums and minimums securing the maximum profit from the forecasting system application for commercial activity. The developed system of forecasting was identified for primary aluminium at the period of 1990-2003. The system was tested daily during 20 months period for speculations on 3M primary aluminium forwards at London Metal Exchange with high commercial result.

Jan 1, 2004

By Clayton Vernon Deutsch, Marcel Antônio Arcari Bassani, João Felipe Coimbra Leite Costa, Vanessa Cerqueira Koppe, Pedro Henrique Alves Campos

Traditional linear approaches oversimplify the complexities of ore blending. Adopting nonlinear blending models in mining and mineral processing is critical to enhancing prediction accuracy and allowing optimization regarding nonadditive variables, such as metallurgical recovery. This study implements a simulated annealing algorithm in short-term mine planning that seeks to optimize the metal recovery by considering how to blend the ore in the mine better. Two nonlinear metallurgical recovery models are used as inputs to the algorithm to represent synergistic and antagonistic blending. The results of the case study demonstrate that the optimized schedule exhibits improvements in both blending behaviors when contrasted with conventional linear-based scheduling plans.

Jan 1, 2025

By Olaf Kessler, Jan Kalich, Michael Reich, Julia Osten, Uwe Füssel

Modern automobile bodies consist of different materials, e.g. aluminium alloys and high strength steels. Mechanical joining, e.g. clinching, is very suitable for joining aluminium and steel sheet. But clinching needs a sufficient ductility, which is no longer supplied by high strength steels. Laser-assisted clinching has been shown, to be able to join aluminium and high strength steel sheet successfully. Thereby the steel sheets were heated locally for short times to increase their ductility. Due to the thermal contact between steel and aluminium sheet the aluminium alloys also achieve a local short-time heat treatment. This fact may cause a significant impact, as aluminium sheet in automobile bodies is often used in T4 (or similar) condition and later artificially aged during the paint bake cycle. Aluminium alloys 6016 and 6181 have been short-time heat treated with heating rates up to some 100 K/s. Precipitation and dissolution processes have been monitored in-situ by calorimetry. Mechanical properties have been investigated on as well as after short-time heat treatment by deformation dilatometry. The results show, that suitable short-time annealing parameters during laser-assisted clinching can increase ductility and at the same time act as retrogression for aluminium sheets, resulting in increased strength after aging.

Jan 1, 2015

By Richard Poulin

Rehabilitation of mined out areas is often enforced by environmental bonding. It is usually assumed that this process provides financial assurance that rehabilitation will be carried out as agreed at the permitting stage. Shortcomings of the current practice in environmental bonding for mining are reviewed. Of particular importance for the public, for governments and for the environment is the absence of protection against cost overruns and companies defaulting before the bond amount is entirely paid. Elements of solution are identified through the emergence of environmental insurance as a complement to bonding for cost overruns and defaults. A cover of environmental catastrophes could also be added, hence reducing the risk for the public and the environment. We examine the merit of creating a captive insurance company under the responsibility of the mining industry. The use of insurance techniques would incorporate a genuine risk management dimension to the financing of rehabilitation.

May 1, 2004

By J. W. Latilla, J. J. van Wijk

A running facebreak ahead of the powered support units occurred on the number 4 seam at Matla Coal’s number 3 shaft (Matla 3) in April and May 2002.Very difficult mining conditions were experienced for a distance of some 150 m in the tailgate and to a lesser extent on the face itself. The paper analyses the main causes for the high stress conditions leading to the facebreak, namely, the existence of a >20 m dolerite sill close to surface and the effect of stopping longwalling on the overlying 5 seam. Difficulties experienced during the facebreak are discussed, including, pillar and roof collapses in the tailgate, high stress areas ahead of the face causing roof and sidewall stability problems, flushing of broken rock into the face area at the tailgate, secondary mid-face breaks, and the availability of critical support units. Successful rock engineering interventions and learning points were that, a goaf angle of 14.6° was found to be more realistic than the previously used 20 to 25° in predicting dolerite sill behaviour in this area, pre-split blasting of the sill significantly reduced stress on the face and tailgate allowing re-support work to proceed, varying pillar support types were analysed and rated, the need to always have a ground control “First Aid” kit available was recognised and a strategy for subsequent panels beneath the sill was developed. Numerous support units were used and the performance of the more suitable types is briefly discussed. A running facebreak ahead of the powered support units occurred on the number 4 seam at Matla Coal’s number 3 shaft (Matla 3) in April and May 2002.Very difficult mining conditions were experienced for a distance of some 150 m in the tailgate and to a lesser extent on the face itself. The paper analyses the main causes for the high stress conditions leading to the facebreak, namely, the existence of a >20 m dolerite sill close to surface and the effect of stopping longwalling on the overlying 5 seam. Difficulties experienced during the facebreak are discussed, including, pillar and roof collapses in the tailgate, high stress areas ahead of the face causing roof and sidewall stability problems, flushing of broken rock into the face area at the tailgate, secondary mid-face breaks, and the availability of critical support units. Successful rock engineering interventions and learning points were that, a goaf angle of 14.6° was found to be more realistic than the previously used 20 to 25° in predicting dolerite sill behaviour in this area, pre-split blasting of the sill significantly reduced stress on the face and tailgate allowing re-support work to proceed, varying pillar support types were analysed and rated, the need to always have a ground control “First Aid” kit available was recognised and a strategy for subsequent panels beneath the sill was developed. Numerous support units were used and the performance of the more suitable types is briefly discussed. Une cassure de taille en avant des unités de soutènement s’est produise sur la veine numéro 4 dans le puits numéro 3 (Matla 3) de la mine Matla Coal en avril et mai 2002. Les conditions d’extraction étaient extrêmement difficiles sur une distance d’environ 150 m dans la voie de tête et, en moindre mesure, sur le front de taille lui-même. L’étude présente analyse les raison majeures pour les conditions de grandes contraintes qui ont conduit à la cassure de taille, à savoir l’existence d’un mur de dolérite de >20m proche de la surface et l’effet d’arrêter la longue taille sur la veine 5 superposée. Les difficultés rencontrées pendant la cassure de taille sont rapportées, y compris les effondrements de piliers et toit dans la voie de tête, les aires de grandes contraintes en avant du front de taille causant des problèmes de stabilité pour le toit et les parois latérales, l’injection de roches cassées dans la taille en voie de tête, les cassures secondaires à mi-taille, et la disponibilité d’unités de soutènement critiques. Interventions minières réussies et leçons apprises furent : un angle de remblai de 14.6° était plus réaliste que celui de 20 à 25° utilisé auparavant pour prédire la conduite du mur de dolérite dans cet endroit ; tir à deux temps du mur a réduit considérablement les contraintes sur la taille et la voie de tête, ce qui a permis un travail de support complémentaire ; des types variés de support de piliers furent analysés et évalués ; la nécessité d’avoir toujours une trousse de première urgence disponible fut reconnue ; et finalement une stratégie pour les panneaux en dessous du mur fut

Jan 1, 2003