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By J Zhou

This paper discusses the implementation of a mixed integer linear programming model for a coal preparation plant. The plant considered consists of primary and secondary heavy media cyclones, hydrocyclones for intermediate fines and froth flotation for the very fine material. The model is designed to optimise the plant settings and product flows to maximise revenues for a given specification for two product outputs. The model can deal with bonus/penalty aspects of the product pricing for products that exceed or fail to meet specification. We report on a model with two separate coal feeds with parallel circuits for the oversize, intermediate and fines streams. The genesis of this model is more than 30 years old but recent improvements in mixed integer programming solvers make a full mixed integer formulation practical. The original model began as an enumeration of cut points with arbitrary rules for product allocation. The product allocation was improved in a linear programming formulation by Gunn (1982) and Sarker (1991 and 1995). Current mixed integer programming capabilities make it possible to replace the enumeration aspects and solve directly as a mixed integer programming problem. The current implementation uses a general purpose modelling language to formulate the model. Open source and commercial mixed integer programming solvers are compared

Sep 26, 2011

By Garth D. Kirkham, James P. Siddorn, Hendri Falck

"Abstract - As an integral part of the Geological Survey of Canada’s EXTECH III Project, a threedimensional computer model has been created of the Con and Giant gold mines in the Yellowknife Greenstone Belt. The Yellowknife Mining Camp has produced a great deal of gold (over 15 million ounces, or 400 000 kg) in the past sixty years and the prevailing assumption is that the mines are at the end of their lives. However, the potential for discovering additional resources using new ideas and technology, and maximizing use of existing data, offers an opportunity to sustain the old mining operations and maintain their contribution to the community.The objectives of this study included the compilation and creation of a three-dimensional Geographic Information System model (combining 3D subsurface data with surface information) to provide a framework for concurrent structural and alteration studies, and to encourage new exploration in the area. A secondary objective was to retain the data in digital format as a historical reference for future remediation efforts, and to document a portion of Canada’s rich mining history.The end result is a database and set of models that have been instrumental in facilitating further exploration in the area, as well as in developing targets for future exploration and mining activities. In addition, the EXTECH III 3D GIS model has made a valuable contribution toward the understanding of the arsenic remediation issues at the Giant mine, and has served as a tool in support of a variety of highly technical engineering studies and for communicating information and problems to the layman and community as a whole."

Jan 1, 2003

The Department of Mineral Resources is the lead agency in mine site environment management and control inNew South Wales. The Department introduced a Mining, Rehabilitation and Environmental Management Plan (MREMP) process several years ago in order to integrate the activities of other government agencies who may have a material interest at the mine site. The MREMP process has resulted in a spirit of trust and co-operation between agencies and between agencies and mining companies. The spirit of co-operation has been reflected in greater public confidence that mining is environmentally responsible.  

Jan 1, 1995

By N. F. Mashinini

Optimization of current control systems, proper maintenance and efficient training of personnel are recommendations made to control the amount of dust that underground employees are exposed to on a daily basis in the coal mining industry. This dissertation forms as part of Sasol Mining?s commitment to protect the health and safety of their employees by suppressing and controlling dust at their mines. This study aims to understand the relationship among mining processes, exposure to dust and dust suppression control measures. The research phase of the project was done at the Sasol Mining Secunda complex where underground visits were undertaken to investigate current control systems and also new systems that are being implemented by Sasol Mining. This work was important because it helped determine the sources of dust underground and also to identify the shortcomings of current control systems and to test the efficiencies of the new systems implemented at Sasol Mining. The most important result of the research work was the identification of which underground operators were exposed the most to dust as this assisted in designing a dust suppression system for the areas where these operators worked. The main conclusions of this study are that the current control systems are sufficient for controlling dust and ensuring dust compliance if they are used efficiently and maintained properly.

Jan 1, 2008

By L. Linzer, J. Oelofse, T. Rangasamy

Extraction of isolated blocks of ground with elevated levels of stress and/or seismicity is a common occurrence in South African gold mines. Isolated blocks of ground that are divorced from the main orebody and are bound by complex, dip and strike parallel, non-persistent geological structures dominate the Klerksdorp gold fields. No quantifiable methods exist to assess the risk associated with mining these and other classes of remnants. A case history, from a gold mine that planned to extract three remnant blocks hosted in a large complex fault system, is used to illustrate the decision making process based on a combination of underground observations, numerical and seismic techniques. Simple risk estimation matrices were developed and used to estimate remnant-mining risk and finally to quantify the decision on which of the three remnant blocks could be extracted at the lowest possible geo-mechanical risk. Il est courant dans les mines aurifères sud-africaines d’extraire des blocs de terrain isolés qui possèdent des niveaux élevés de contraintes et/ou sismicité. Les régions aurifères de Klerksdorp sont dominées par des blocs de terrain isolés qui sont séparés du gisement principal et qui sont retenus par des structures géologiques non continues, à parallèle de pendage et direction, et complexes. Il n’existe pas de méthodes quantifiables pour évaluer le risque associé à l’extraction de ce genre et autres genres de résidus. Une observation de cas, celle d’une mine d’or qui avait l’intention d’extraire trois blocs de résidus qui se trouvaient dans un grand système complexe de faille, est utilisée pour illustrer le processus décisionnel basé sur une combinaison d’observations souterraines, et de techniques numériques et sismiques. Des matrices simples d’estimation de risque furent développées et utilisées pour estimer le risque lié à l’extraction des résidus et finalement pour quantifier la décision sur lequel des trois blocs de résidus pouvait être exploité au moindre risque géo-mécanique. Die Extraktion isolierter Gesteinsblöcke mit erhöhtem Spannugsniveau oder Seismizität ist in südafrikanischen Goldminen üblich. Isolierte Gesteinsblöcke, die von der Haupterzader getrennt und durch komplexe, parallele abfallende und horizontale nicht persistent geologische Strukturen gebunden sind, beherrschen das Klerksdorp Goldfeld. Es gibt keine quantifizierbare Methoden die das Risiko welches mit dem Abbau dieser und anderer Klassen verbunden ist beschreiben. Eine Fallstudie einer Goldmine, welche die Extraktion von drei in einem großem komplexen Verwerfungssystem eingelagerten Einschlußblöcken plante, wird verwendet um den Entscheidungsprozeß zu illustrieren, der auf einer Kombination von Untertag Beobachtungen und numerischen und seismischen Techniken basiert. Einfache Gefahreinschätzungsmatrizen wurden entwickelt und angewendet um das Abbaurestrisiko abzuschätzen und letztendlich die Entscheidung zu quantifizieren, welcher der drei Einschlußblöcke unter dem niedrigst möglichen geo-mechanischen Risiko extrahiert werden konnte .

Jan 1, 2003

By Amin Mousavi, Soroush Khazaei, Yashar Pourrhimian

As a factory-like method, sublevel caving consists of development activities, stockpiling and production activities that are carried out on different levels independently. Therefore, considering the operation from the development phase to the plant will lead to more reliable production scheduling. This paper presents a mixed integer linear programming framework for the long-term production scheduling of sublevel caving that maximizes the net present value while satisfying development activities, mining, and processing capacities, continuous mining, the allowable number of active mining units, grade blending, and vertical and horizontal sequencing. The model is coded in Jupyter Notebook and is solved using the CPLEX solver.

Jun 25, 2023

By Y. Luo

Based on the concept of slope stability analysis, a formula for determining an important parameter required in the mathematical model for the prediction of mining subsidence in hilly terrain has been proposed. The slope geometry and soil physical and mechanical properties of the surface natural slope can all be considered in the formula. Incorporation of this new formula into an existing mathematical model provides an integrated approach in studying ground movement in hilly regions.

Jan 1, 1998

By Gaspard Devos

1. A NEW CONTEXT FOR METAL INDUSTRY Producers and owners of industrial extractive sites are living hard times due to Environmental pressure and liabilities. This is valid whatever the region in the world, it is just a question of time. On one hand, the normative environmental pressure is increasing through more severe regulations and controls on all pollution sources and production materials. [ ] Furthermore, more impurities are extracted and captured, more the volume of the related wastes is increasing. But disposal costs are increasing, disposal areas for wastes are restricted, markets for wastes are limited and technologies for waste treatment are, most of the time, not available. On the other hand, for most of the extractive industries, the costs required to get access to refine primary raw material are killing the profitability of the industry. Definitively, a technological and economical breakthrough is ongoing: extractive industries have to increase their feed from secondary material and to be involved more and more with the recycling business.

Jan 1, 2005

By Michael J. Rinker, P. A. Tibble, M. Wiseman, R. V. Nicholson

Tailings, from an active copper-zinc operation, containing about 10% sulphur were investigated to assess the onset of acid production and potential lime requirements for treatment of drainage. Oxygen consumption rates were measured over two years to verify spatial and seasonal variations in sulphide oxidation rates. Shallow cores were collected to assess the quality of tailings porewater and to characterize solids that had been subjected to oxidation and depletion of neutralization potential (NP) for several years. Oxygen consumption data were used to quantify rates of NP depletion and onset of acid drainage from the near- surface tailings. Based on measured oxygen consumption rates and identification of NP remaining in the tailings, future lime use in the treatment plant was expected to rise significantly without mitigation. Geochemical modeling calculations were calibrated with observed oxygen consumption rates and the model results agreed well with actual lime use in the waste water treatment plant during operations. The modeling also demonstrated the benefits of lower lime demands and treatment costs after closure as a result of construction a soil cover on the acid generating tailings.

Jan 1, 2000

By M. Santaluce

"The revamp of critical process assets that require a significant plant outage (shutdown) presents a unique and demanding set of challenges for plant operators. They are executed in a more complex Brownfield environment, typically with limited working space and often involve unknown conditions or scope. For plant operators, such a project is often a high cost event both in terms of opportunity cost of lost production and the resource cost of labor and materials. It can also be a high risk event in terms safety, environment, and future plant reliability/availability. This impacts current and future performance or Overall Equipment Effectiveness (OEE). In our experience, the sequential nature of the EPCM approach does not provide the proper framework to facilitate the level of coordination, stakeholder cooperation and detailed planning required to adequately address the construction and shutdown complexity of a critical asset revamp projects. This paper proposes a more integrated approach to handling shutdown revamps of critical assets. Its main thesis is to involve the key performing stakeholder groups early in the project lifecycle (engineering team, procurement team, construction team and plant operations) to form an integrated shutdown management team that is focused on ensuring delivered results are aligned with project objectives. In this model, the construction team executing the shutdown/construction is preparing the detailed shutdown/construction planning concurrently with detailed engineering and procurement planning. This allows construction/shutdown requirements to influence engineering and procurement, with the desire to optimize safety, speed, quality and cost. The paper also discusses how to overcome the procurement hurdle in applying such an approach. The outcome of this integrated approach is better planning, coordination, communication and alignment between the project stakeholders, a shutdown/construction driven planning approach that more fully addresses the challenges of these projects and delivered results that are aligned with project objectives."

Jan 1, 2015

By M Kent, D Elder, J Woodward, R Edwards, B Catto

At Tropicana gold mine (TGM), mine planning is completed from ‘one source of truth’ known as the Integrated Planning Model (IPM). The IPM is a block model which forms a core component of the TGM Mine Planning System – used for short, medium and long-term mine planning cycles, and for Mine to Mill reconciliation.The IPM was developed from a desire to consolidate long-term information contained in mineral resource and ore reserve models, with short-term information from the grade control processes, including grade control models and ore polygons.The IPM is informed initially by resource models, upon which the longer term budget and schedules are based. The IPM is routinely updated with grade control models and ore design information, providing increased confidence for short to medium term mine planning. In this format, the IPM also provides a framework for reconciliation of resource performance with grade control, mining actuals and mining schedules, and ultimately milling. As well as a means for analysing past performance through reconciliation, it has proven its worth as a predictor of variation and an input to successful schedule sequencing and change management. The IPM is a critical component of the TGM Mine Planning System, providing a centralised framework for short interval mill feed prediction through to life-of-mine (LOM) planning.Current development of the IPM is working towards incorporating Mine to Mill optimisation and real-time material tracking projects at TGM. If successful, the model will provide a truly powerful mine planning data source. Current development outlines a mechanism for tracking material from Mine to Mill, and for transferring mill performance data back to the IPM. Increasingly advanced material classification and mine planning, incorporating the multiple geometallurgical variables, will enable the mine to provide consistent mill feed products and result in a steady state and optimised mill.This paper outlines the vision, creation and benefits of the IPM at TGM. It also introduces the ongoing developments to ensure the IPM becomes only more relevant to successful and integrated mine planning as TGM matures from the new kid on the block to the old hand in the neighbourhood.CITATION:Catto, B, Elder, D, Edwards, R, Kent, M and Woodward, J, 2017. An integrated approach to mine planning – building the integrated planning model at Tropicana gold mine, in Proceedings Tenth International Mining Geology Conference 2017, pp 305–314 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By Barun Gorain, Andy Stradling

"The traditional metallurgical scale-up techniques for flotation plants are based on lumped flotation rate constants, dimensionless hydrodynamic numbers and the use of safety factors. Once the plant has been designed, the flotation principles that govern scale-up play almost no role in the optimisation of the circuit to meet its metallurgical targets. This deficiency can potentially lead to a plant design incapable of meeting its targets, especially when circuits incorporate large flotation cells. This paper demonstrates the application of the k = PSbRf model in providing a suitable framework for flotation modelling, scale-up and circuit optimisation, thus presenting an integrated approach to the problem. Studies were conducted at Teck Cominco’s Red Dog concentrator to characterise cell hydrodynamics, gas dispersion properties, fioth flow behaviour, entrainment and ore floatability to obtain the key data necessary to develop a model for the flotation circuit. The findings of these studies are presented in this paper, which provide valuable insights into the modelling and optimisation of the Red Dog flotation circuit.INTRODUCTIONThe traditional methodology for flotation scale-up and plant design is based on the rule-of-thumb with safety factors, dimensionless hydrodynamic group similitude considerations, etc. With the recent trend towards larger flotation cells with volumes of 150 m3 and greater in concentrators, the problem of scale-up has become even more acute. The scale-up factors that may have been tolerated on smaller cells are not applicable to larger cells. The transportation of froth in these large cells adds further complexity to the problem. Arbiter et al. (1980) foresaw this problem and pointed out that if scale-up were attempted by rule-of-thumb and trial-and-error, then the probability of failure would increase with scale. This problem is confounded by the fact that the design and scale-up considerations used for a new flotation circuit play almost no role in optimisation of the circuit to meet its metallurgical target. This results in a plant design incapable of meeting its metallurgical targets. There have been several instances where new concentrators have required significant circuit modifications and additional capacity to achieve design targets."

Jan 1, 2002

By A Riles

"Three issues of relevance in a modern tailings storage facility (TSF) are:geotechnical stabilitymanaging acid rock drainage (ARD) from pyritic tailingsmanaging the tailings from cyanidation of gold ores. Drawing on examples from both copper porphyry flotation and sulfide-hosted gold ores, this paper demonstrates that giving some weight and importance to the process tails properties upfront can influence the flow sheet and not only improve tailings management effectiveness but also impact positively on economics. In the case of a typical copper porphyry ore with moderate pyrite content, the rougher tail in a conventional high pH selective flotation step is usually classified as potentially acid generating (PAG). To avoid the generation of ARD within the tailings and the requirement for a costly plastic lining, subaqueous deposition is recommended, which in turn has negative implications for tailings stability, consolidation and closure. Adopting a neutral pH rougher stage rejects silicate gangue but recovers pyritic material to the cleaners for a subsequent selective flotation stage, often after regrinding. This effectively quarantines the PAG pyritic material in a much lower volume cleaner tail, which can then be appropriately encapsulated within a larger non-lined flotation tails facility. It also facilitates cyanide leaching of the cleaner tail for gold recovery, with the encapsulated tailings facility being suitable for cyanidation tails storage. A case study from Europe is examined. For gold ores where the gold is sulfide-hosted, but not refractory, a flotation route with cyanidation of the concentrate can similarly produce the majority of tailings as a benign flotation tail and again quarantine the low volume concentrate leach tail in a small encapsulated cell with appropriate residual cyanide management measures applied. Overall economics for intensive leaching of a low volume concentrate stream can also be surprisingly positive. A feasibility study design example of the process and TSF is presented. CITATION: Riles, A, 2016. An Integrated Approach to Optimising All Concentrator Products, Including Tailings, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 341–346 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By E. Córdova, A. Anani, W. Nyaaba

Optimization of panels, haulage fleet, and waiting area involves deterministic and low-fidelity methods and experiential knowledge. The process is challenging because coal recovery and operational capabilities must be considered in the solution. The approach in this manuscript comprises the development of an integrated stochastic simulation model of a coal room-and-pillar system that addresses these challenges. The decision variables evaluated are panel width, number of shuttle cars, and change-out time (COT). The results show that the mine should implement the shortest possible COT, decreasing the cycle time and thereby increasing productivity and continuous miner (CM) utilization. The highest productivity and CM utilization for a fleet size of three shuttle cars is found in the 15-entry panel width. For the evaluated fleet sizes, the 19-entry panel width is optimal for the four and five shuttle cars. Among the three variables studied, panel width and fleet size had the most significant effects (5% increase) on the CM productivity, cycle time, and utilization.

Apr 2, 2022

By T Huynh, K Tungpalan, E Wightman, M Edraki, S Palaniandy

Most preventive environmental management practices promote proactive integrated approaches to waste management. For example, life cycle assessment is often used to find the ‘hot spots’ of environmental burdens. This kind of approach is often based on generic data and has rarely been used for tailings. Besides, life cycle assessments are less useful for designing operations or simulating changes in the process and consequent environmental outcomes. It is evident that an integrated approach for tailings research linked to better processing options is needed.The aim of this Nextmine™ project is to develop new tailings management models by streamlining orebody characterisation, process optimisation and rehabilitation. We present an integrated tailings management approach and preliminary results from a case study. Combined grinding and flotation models were developed using geometallurgical data from the orebody, to predict the properties of tailings produced under various processing conditions. The modelling scenarios based on the case study data provide the capacity to predict the composition of tailings and the resulting environmental management implications. For example, the type and content of clay minerals in tailings will affect the geotechnical stability and water recovery. Clay content will also influence decisions made for paste or thickened tailings and underground backfilling.CITATION:Edraki, M, Huynh, T, Wightman, E, Tungpalan, K and Palaniandy, S, 2015. An integrated approach to proactive tailings management, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 323–332 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By Ian Misich

A research programme has been undertaken to evaluate and predict the effect of total extraction of coal by underground methods on the superimposed strata, aquifer systems and ground surface in the Collie Basin. Western Australia. The research work has integrated comprehensive field monitoring of surface and subsurface subsidence with empirical, analytical and physical modelling in an effort to develop an effective predictive tool which can be used in all mining scenarios. Early results indicate that although each method has certain limitations, this approach has enabled the researchers to develop a very good understanding of the subsidence mechanisms from the mine panel through to the surface in the weak, water saturated sediments in the Collie Basin. Given that both subsurface and surface subsidence characteristics have tied in well, greater confidence can be held for predictions made by representative models.

Jan 1, 1993

By A. Chrzanowski

The integrated approach to monitoring surveys is based on a simultaneous utilization of geodetic, photogrammetric and geotechnical measurements of displacements, tilts, strains and any other geometrical parameters of deformation. New techniques for the integrated surveys are being developed at the University of New Brunswick in cooperation with the Canada Centre for Mineral and Energy Technology. A telemetry system for continuous monitoring of geotechnical measurements under difficult climatic and topographic conditions has been constructed and successfully tested in a coal mining area in western Canada. A generalized method for analysing the integrated deformation measurements has been developed and applied in the test area to yield three dimensional empirical modelling of surface movements from geodetic, photogrammetric and tilt surveys. The most appropriate model can be chosen from a statistical assessment of several modelling possibilities. The empirical model of the deformation can be employed in a "calibration" of the prediction (deterministic) model of the ground movements. A computer programme for two- and three-dimensional finite element modelling of elasto-plastic deformations has been developed at UNB as a part of the integrated approach. The :EM has been tested in predicting deformation in the test area in difficult geological conditions which were associated with an extraction of a steeply inclined coal seam. The results gave good agreement with the actual displacements obtained from geodetic measurements and confirmed the existence of a suspected fault.

Jan 1, 1984

By M. Canty

An innovative biological treatment system designed to detoxify cyanide and nitrate and immobilize metals from cyanide leach operations is described. A pilot-plant demonstration was conducted to detoxify cyanide and immobilize several metals from a process stream at the McCoy/Cove Mine. Testing was performed under the EPA's Mine Waste Technology and Superfund Innovative Technology Evaluation Demonstration Programs. This technology was successful in detoxifying cyanide and effective in removing metals. The pH was consistently neutralized and nitrates were successfully removed. Results show that biological treatment can offer an innovative, cost-effective alternative for the treatment of mining wastewaters.

Jan 1, 1999

By H. Eccles

BNFL, an internationally acclaimed company noted for its nuclear fuel cycle services and waste management technologies, collaborated with Viridian BioProcessing Ltd, a small company acknowledged for developing environmental biological processes, and an internationally recognised professor of biological sciences, to develop an unique bioremediation process for treating toxic, heavy metal contaminated land. This paper describes the process, with particular reference to the problem and scope of land contamination with toxic, heavy metals and the current available technologies. The process technologies are based on using indigenous, soil micro-organisms which can be stimulated to produce acid or sulphide ions to mobilise or precipitate the heavy metals respectively. Laboratory studies have indicated metal removal efficiencies of greater than 90 % can be achieved, whilst recovery efficiencies from the metal loaded leachate are even higher at approximately 95%.

Jan 1, 1996

By C Tapia Cortez, A G. Dempster, R Fradet, S Saydam, T de Roche, R Shishko, J Coulton

Human ventures into space are entering a new phase in which missions formerly driven by government agencies are now being replaced by those led by commercial enterprises – in launch, satellite deployment, resupply of the International Space Station and space tourism. In the not-too-distant future, commercial opportunities will also include the mining of asteroids, comets, the Moon and Mars. This research examines the role of off-Earth mining in a growing space economy. In this investigation, the term ‘mining’ is taken to embrace minerals, ice/water and other in situ resources. As the off-Earth mining initiative could be the engine that drives the space economy, it would be useful to understand what off-Earth mining market conditions and technology requirements are needed for that economy to prosper. These specific elements are studied in the wider context of creating an economy that could ultimately support a sustainable Mars colony. The methodology for developing the model focuses on the extraction of ice from the surface of Mars to produce propellant and water for life support for a possible colony.CITATION:Saydam, S, Shishko, R, Tapia Cortez, C, de Roche, T, Fradet, R, Coulton, J and Dempster, A G, 2015. An integrated economics model for in situ resource utilisation in support of a Mars colony, in Proceedings Third International Future Mining Conference, pp 305–312 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015