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By J. Little

It is common practice for underground mine plans to be created sequentially, where results from one planning process form the input data for another. While this is practical for manual methods, computerized optimization techniques should consider an integrated approach to creating the global mine plan. This is because optimizing an individual mine planning process, such as stope layouts, introduces a likelihood of increasing costs or decreasing revenues associated with other areas, such as production scheduling, as harmful decisions must be balanced. Considering the interaction and influence that individual underground mine planning processes have on each other during optimization will provide more profitable results than if these are ignored. Optimization techniques for stope layouts and production scheduling are reviewed. An integer programming model is proposed that allows for either integrated or isolated optimization. Both approaches are separately applied to a block model. The results demonstrate the model?s ability to produce optimal long-term sublevel stoping mine plans and the benefits of using an integrated approach. Keywords underground mine optimization, stope layouts, underground production scheduling, integer programming, mathematical programming application.

Oct 1, 2013

The Challenges in Mining _Large expensive assets that are not being utilised as well as they should _?Silo? operations plan, schedule and execute in isolation?poor visibility across the Value Chain _Disruptions or unforeseen events have serious upstream and downstream impacts _Exacerbated by multiple information systems, mostly spreadsheets _Strategic simulation (supply and demand) is often poorly Handled

Nov 1, 2011

The development of short- and medium-term mine production schedules in isolation from each other has meant that only a local optimum can be achieved when each scheduling phase is carried out. The globally optimal solution, however, can be achieved when integrating scheduling phases and accounting for the interaction between short-term and medium-term activities simultaneously. This paper addresses the task of integrating short- and medium-term production plans by combining the short-term objective of minimizing deviation from targeted mill feed grade with the medium-term objective of maximizing net present value (NPV) into a single mathematical optimization model. A conceptual sublevel stoping operation comprising 30 stopes is used for trialling segregated and integrated scheduling approaches. Segregated medium- and short-term scheduling using separate models achieved an NPV of $42 654 456. The final scheduling approach involved integrating the two scheduling horizons using the newly-developed globally optimal integrated production scheduling model to achieve an NPV of $42 823 657 with smoother mill feed grade. The larger the stope data set, the larger the difference between the two scheduling approaches is likely to be. At the very least, an integrated approach ensures feasibility across the two scheduling horizons, which cannot always be assumed when using a segregated approach.

Jan 1, 2012

By R. J. Baumgartner

Sustainability issues are from rising interest and importance for the mineral industry worldwide. In order to bring them into management processes and to improve decision processes, economic, ecological and social aspects of products, services or technologies have to be assessed. In this paper, the concept of integrated sustainability assessment is presented. Each aspect is assessed with quantitative or qualitative methods. The results of these ecological, social and economic sub-assessments are integrated by the means of Fuzzy Logic in order to regard preferences of decision maker and circumstances of decision situation. An example demonstrates the application of this new instrument.

Jan 1, 2005

By Bern Klein, Malcolm Scoble, Justin Widdifield, Andrew Bamber

"It has been suggested that the pre-concentration of ore underground can bring positive economic and environmental benefits to underground mining, particularly at extreme depth. The integration of mineral processing systems for coarse waste rejection and disposal into the underground mining environment has a substantial impact on the economics and operation of the mine. A case study for the integration of underground pre-concentration at Falconbridge’s Thayer Lindsley and Fraser Copper operations in Sudbury, Ontario is discussed, with particular focus on ore evaluation, system design, integration, and impacts on the operation. Conclusions as to the overall feasibility and potential impacts of underground pre-concentration are presented.INTRODUCTIONObjectivesA scoping investigation has been conducted for Falconbridge Ltd on the Fraser Copper Zone and Thayer Lindsley mines in order to develop a better understanding of the operations, and to do a preliminary evaluation of the potential for pre-concentration of the ore underground. The objective was to develop a conceptual design and evaluation of a pre-concentration system for each site. The results are to be used as the basis for a more detailed future study.Underground Pre-ConcentrationThe pre-concentration of ore to reduce the quantity and improve the quality of material transported to the processing plant is not a new concept and has been in practise at several mines including the American Zinc Company in Mascot Tennessee (Munro et al, 1982), the Sullivan Mine in British Columbia and presently at Xstrata’s Mt Isa lead-zinc mine in Australia, as well as at several PGM mines operating in the South African Bushveld. For each of these mines, a high degree of waste rejection was achieved at a coarse particle size with good metallurgical recoveries. The benefits arising from the surface pre-concentration of ore are well documented in the literature (McCullough et al, 1999; Miller et al, 1978; Munro et al, 1982; Schena et al, 1990; Sivamohan & Forssberg, 1991)."

Jan 1, 2006

Integrated Utilisation of Desulfurisation and Skimming Slag

Sep 13, 2010

Various software packages are discussed. These are components of an Integrated Planning and Scheduling System developed by MVM with the aim of providing up-to-date information for the Whaleback operation on: 1. Mine Topography. 2. Status of equipment in the mine. 3. Material moved from and within the mine. 4. Volume and density of same. 5. Quality of same.

Jan 1, 1986

By P Holtham, K Duffy, W Valery, A Jankovic

As high grade ore deposits are depleted, remaining deposits are generally lower grade and require the mining and processing of larger volumes of material per tonne of product. These low grade deposits often contain a large proportion of barren gangue. Pre-concentration aims to remove this barren material at as coarse a particle size and as early in the process as possible. This has the potential to reduce processing costs, energy and water consumption, increase production and improve resource utilisation.There are several technologies that may be applicable for pre-concentration. This paper looks specifically at bulk ore sorting and how it can be integrated into existing or new mining operations to improve profitability and reduce environmental impact. Bulk ore sorting is the separation of barren gangue from a fully loaded conveyor belt based on the grade as measured or inferred from a sensor measurement. It may be used to increase the production rate through fixed plant capacity, or increase production and/or reduce the size of downstream processing equipment in Greenfield operations. Marginal ore sub-economic reserves may be upgraded, making them economic to treat and improving the resource utilization. Bulk ore sorting could also be used to reduce dilution and ore loss in mining operations by improving grade control, or to separate ore types to treat via different process routes. Various applications of bulk ore sorting are discussed in this paper, and three cases are investigated considering the impact on the overall operation and the associated benefits.CITATION:Duffy, K, Valery, W, Jankovic, A and Holtham, P, 2015. Integrating bulk ore sorting into a mining operation to maximise profitability, in Proceedings MetPlant 2015, pp 273–287 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By K. A. Larsen, J. L. Ariail, C. M. LaRosa

This article discusses the evolution of U.S. laws and policies towards environmental remediation at mine lands over the last 20years, the opportunities that these changes present for reuse, and the remaining challenges associated with community capacity for effective reuse planning and implementation. Emerging initiatives by the U.S. Environmental Protection Agency and Department of Interior for addressing these challenges are discussed.

Jan 1, 2004

By S. Stoyanov, M. Cross

"Silicon components containing transistor circuitry are at the heart of electronic products such as computers, mobile phones, etc. These components are connected to printed circuit boards (PCB's) using solder material that acts as the conductor for both electricity and heat. During the lifetime of a product it will undergo many thermal cycles where the chip becomes hot during product operation and then cools when the product is switched off. At the product design stage engineers undertake thermo-mechanical simulations to predict the thermal stress in the solder joints due to this thermal cycle and to ensure that the stress magnitude will not result in early fatigue-type failure. The design engineer's aim is to identify component parameters which ensure that the solder will survive beyond a certain number of thermal cycles.The aim of integrating computational mechanics and optimization tools together is to speed up dramatically the design process. From viewpoint of a design engineer in the electronics manufacturing sector, these tools can be used to quickly estimate key design parameters (i.e. material properties, product dimensions, etc) that will guarantee the required product performance. In this paper a modeling approach coupling computational mechanics techniques with numerical optimization is presented and demonstrated. The integrated modeling framework is obtained by coupling the multi-physics framework - PHYSICA - with the design optimisation tool- VisuaLDOC. Thermo-mechanical simulations are presented that predict the creep strains in solder material. Different numerical optimization procedures: Direct and Response Surface based optimization plus Design of Experiments, are tested as a part of this modeling framework."

Jan 1, 2001

By McAuley T. J

Computer software is an integral part of mining operations today with many sites using six or more software packages on a daily basis. However, the use of these different programs generates the need for substantial staff training. The current trend toward large integrated packages to solve this problem is counter-productive because the relatively small companies producing specialised mining software do not have the resources to develop quality software with all the required features. Software standards are being proposed by various parties but recent history indicates these will be unsuccessful. An alternative approach is suggested using the various standards which have been developed for the Windows operating system.

Jan 1, 1995

There are a number of examples of how environmental factors have been integrated into the water management aspects of mining projects. The Kingston Lignite project in South Australia, Pine Creek Gold Mine in the Northern Territory, gravel and sand extraction from the Nepean River flood plain near Penrith, and the Olympic Dam Project have all illustrated that consideration of environmental factors can be integrated with project developments, with beneficial outcomes for both the project and the environment.Each of the above cases demonstrated an individually significant environmental issue, directly related to the interaction between the proposed project and its environment. In each case, careful research and an integrated approach to the problem resulted in a solution that gave both maximum protection to the environment and optimum consideration to the economic feasibility and success of the proposed project.The solutions ranged from alternative mining methods and improved waste and water management through to the ultimate objective of converting a mining project into a major water-based recreation source. These examples have set a precedent that will contribute ignificantly to the successful development of future projects.

Jan 1, 1988

By W. J. Mcgaughey, M. A. Vallée

"Abstract -The application of geophysical technology to resource delineation aims to improve the quality of resource/reserve estimates by integrating high-resolution survey methods, geophysical modeling and inversion with three-dimensional representations of geological and mineral deposit data. The use of geophysics can cost-effectively improve a geological interpretation based only on geological and sampling data. Success depends upon the ability to use geological visualization and modeling software, first to develop a three-dimensional geological model and then to modify it interactively by integrating geophysical data with the geological and sampling data.The high resolution required for mineral delineation geophysics results in a focus on borehole seismic and high-frequency electromagnetic methods. Borehole wireline logging is used to develop an understanding of the relationship between physical properties and geological description. Data from core samples and borehole wireline logs allow the construction of a three-dimensional physical property distribution, consistent with the existing geological interpretation. The three-dimensional physical property distribution is used for both geophysical forward modeling (to compare to field data) and as a starting model in iterative inversions.Advanced visualization techniques allow the simultaneous viewing of the three-dimensional physical property model, the geological information and data from which it is derived, and the geological interpretation and the geophysical results. Geophysical results may be simulated responses from a forward model or the output from a numerical inversion in the form of an updated physical property distribution. Iterative refinement of the geological interpretation is required to ensure consistency with the geological and geophysical data. The key to success with this approach is that all relevant geological, geophysical, and rock property data reside in a common, visual model of the earth.Examples from massive sulfide deposits illustrate the benefits obtained by the integration of geophysical and geological data."

Jan 1, 1998

By William Shaw

Conditional simulation is now an accepted tool for managing ore block design at a number of operating mines. It provides a way to consider the quality of data, local continuity and economic risk in defining ore and waste across the cut-off boundary. In addition a computer based system can ensure consistency in making decisions to meet multiple criteria such as cut-off grades, minimum ore-block size and contaminant grade limits. The development of a procedure for using multiple criteria allows ore blocks to be defined using alternative strategies depending on the specific production requirements. This has introduced the opportunity to define ore blocks for different destinations based on their material types and opens the way for geometallurgical modelling to be incorporated into grade control.

Oct 1, 2009

By Seal. Thom

Large heap leach operations around the world contain significant under-leached metal values that present recovery challenges to operators. The first challenge is to find the location of the highest inventory. High resolution resistivity ? has proven sensitive enough to detect such zones in the interior of heap leach pads to target treatment or re-leaching. Newmont Mining Corp. has adapted the high pressure fracturing technology, used in oil wells to stimulate select zones in heap leach pads to add reagents in 3-D for re-leaching, changing zonal chemistry for improved recovery and heap closure. High Resolution Resistivity ? is able to subsequently monitor injected solution flow and determine directional permeability during Hydro-Jex stimulation. The combination of these technologies has shown strong economic success, for selecting targets in the heaps and monitoring solution application. These technologies are now available to the mining industry for adoption.

Jan 1, 2008

By Maya Kamenetsky, Khoi Nguyen, Natalee Bonnici, Steve Walters, Claire McMahon, Julie Hunt, Ron Berry

"The analysis of meso- and micro-scale textural attributes has been undertaken on ore samples from the Ernest Henry iron oxide-copper-gold (IOCG) deposit in NW QLD. Quantified textural data including grain size, shape and mineral association have been extracted from classified images of core with the aim to better predict potential mineral processing behaviours such as comminution, liberation and flotation. Data have been extracted from images of intact core at meso- and micro-scales using high resolution continuous images collected using automated core-logger technology, SEM-based and optical microscopy platforms.The results of this study will show examples of quantified size, shape and mineral association data from meso- and micro-scale classified images. Analysis of the data shows that there are domains of variable grain size and mineral association that can potentially be related to crushing and liberation behaviour. The trends that are observed at the drill-core (meso-) scale are consistent with those at the micro-scale. The results from the micro-scale analysis show that the domains defined at the core-scale have clearly different chalcopyrite sizes and shapes as well as variable bulk mineralogy.INTRODUCTIONInnovations in technology have allowed automated extraction of information about mineral shape, grain size and mineral association, i.e., texture, from meso- and micro-scale images of intact rocks. The overall aim of this research is to investigate trends in quantified textural data that can potentially give an early view of processing parameters such as predicted grind size and liberation behaviour."

Jan 1, 2009

By Laura Mottola

This paper outlines a framework for ensuring the success of the implementation phase that follows research and development of new mining technologies and systems. It is based upon recent and past lessons learned that have demonstrated the critical challenges to effective technology transfer, which frequently receive inadequate attention within the culture of the mining business. The paper focuses on mining automation implementation challenges and then outlines a Roadmap which is proposed as an integrated framework to deal with the key aspects of people, process and technology. This framework is built upon: assembly of a Strategic Team to develop a Roadmap; fully understanding the business requirements of the technology initiative; defining Key Performance Indicators in a Balanced Score Card; performing a Stakeholder Analysis to identify the affected groups; and finally developing a master Project Plan to execute the Roadmap.

Oct 1, 2009

By Roshan B. Bhappu

Integrating a research and development department into an engineering company's corporate structure can be rewarding to the engineering division, the R&D group, and, most of all, the company's clients. Actually, the R&D department is a logical extension of the conventional processing group within an engineering organization-but the R&D group provides services as needed to the engineering department while it is carrying out regular testing, pilot plant, and preliminary feasibility studies. Backup Services Provided With an R&D group, the engineering division does not need a process engineering group as such. The R&D group provides project backup services for feasibility studies, preliminary and detailed engineering, construction, and startup. The R&D group, in turn, benefits from its close association with project engineers, draftsmen, estimators, and computer capabilities in the engineering division. The client also benefits from the arrangement because R&D and engineering skills are available to both departments on an as-needed basis without standby eost. To handle the integrated responsibility of R&D projects, as well as conceptual design and preliminary feasibility studies, the R&D staff must be carefully selected. These research engineers should: • have a good background in plant practice as a mill superintendent or chief metallurgist; • be capable of organizing and supervising a testing program or a pilot plant campaign; •be innovative and willing to accept new ideas and concepts; • be able to translate lab test results into a workable flowsheet through sound conceptual design and feasibility studies; and •be able to communicate with clients. In short, the R&D engineer must be a jack of all process-engineering trades to successfully take a project from concept to operating reality. Engineers in a metallurgical R&D organization should have experience in mining and processing all types of

Jan 10, 1980

By E. J. Haas, K. A. Rost

"This study sought to identify changes in continuous mining machine (CMM) operators’ risk perception and risk behaviors as a result of adding a proximity detection system (PDS) into their environment. To accomplish this research task, 9 CMM operators from 5 locations were interviewed. Interviews were thematically analyzed for constructs including patterns in risk perception and behavior before and after PDS integration and the process of adapting to the PDS. Operators discussed standing in the red zone less than they did before using the PDS; however, they also discussed other risky decisions they made while learning how to operate their CMM with the PDS technology such as “cheating” the technology and working faster to meet production goals. The process of relearning job tasks with technology and unintended behaviors as a result of that relearning process need to be taken into account when introducing new technology into the mine environment. The study results show an in-depth view of mine workers’ perspectives and how their job tasks and environment could be or are affected when learning how to use new technology that are relevant to companies and mine operators when introducing new technology into the mine environment. INTRODUCTION Established “red zones” can help prevent striking and pinning incidents by providing guidance to continuous mining machine (CMM) operators about where they should stand and not stand while operating a CMM. Although red zones influence operator placement positions, these guidelines are not foolproof safety mechanisms. Depending on the job task and circumstances of the mine environment, a CMM operator may unintentionally or intentionally stand in a red zone. For example, CMM operators may work in close proximity to their CMM for better visual attention cues and the ability to work at a higher rate of production [1-3]. To further enhance protection and prevent collisions between vehicles and mine workers, a proximity detection system (PDS) was developed for the industry. The PDS determines an individual’s position relative to a specific piece of machinery, issues visual and/or audible warnings to the mine worker to change positions, and, if necessary, disables machine motion [4]. The introduction of new technology within other sectors has been identified as a factor that influences work decisions. Specifically, previous research demonstrates that when technology debuts there can be an initial intrinsic risk perceived among users about how the technology will interact with their current environment and behaviors; however, these ambiguities, including the possible risks and benefits, are seldom studied [5]. Some research suggests that the constant presence of technology can disrupt situation awareness and decision-making capabilities by increasing worker responsibilities and worker cognitive demands [6-8]. Further, if workers’ perceived risks both with and without technology are misjudged, unsafe decisions that result in human error and injury may be more likely [9-11]. Although these statements are provided within a broad contextual framework, they support the need to study how technology is perceived among end users in their own environment. Because research about technological impact on worker behaviors has suggested both positive and negative consequences of technology, this issue is worth addressing in the mining industry. Specifically, research has not determined whether CMM operators view their placement choices in the red zone as safe or risky and what effect PDS technology has, if any, on risk perception and subsequent risk behavior."

Jan 1, 2015

By Igor Gonzales G.

The Southern Peru Copper Corp. (SPCC) recently built an integrated copper project consisting of dump- and heap-leaching operations at its mine complex in Peru. The pregnant leach solution (PLS) containing the solubilized copper from the leaching operations is processed in a new solvent extraction/electrowinning (SX/EW) facility to produce high-purity cathode copper. The dump leaching and SX/EW facilities are located near the Toquepala mine site. The crushing and heap-leaching operation is located at the Cuajone Mine. The pregnant leach solution from Toquepala and Cuajone is pumped 35 km (22 miles) to the SX/EW plant at Toquepala. The SX/EW plant consists of three trains of solvent extraction (SX), a tank farm area and an electrowinning (EW) facility. The solvent extraction plant has a total PLS flow capacity of 3,210 m3/hr (113,360 cu ft/hr). The electrowinning facility has an expected long-term production capacity of 97 t/d(107 stpd) or about 35 kt/a (38,500 stpy) of cathode copper. However, present production exceeds the expected long-term by about 20%.

Jan 1, 1996