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Modelling Geological Uncertainty For Stochastic Short Term Production Scheduling In Open Pit Metal Mines
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Book Synopsis Modelling Geological Uncertainty for Stochastic Short-term Production Scheduling in Open Pit Metal Mines by : Arja Jogita Jewbali
Download or read book Modelling Geological Uncertainty for Stochastic Short-term Production Scheduling in Open Pit Metal Mines written by Arja Jogita Jewbali and published by . This book was released on 2006 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis The Stochastic Optimization of Long and Short-term Mine Production Schedules Incorporating Uncertainty in Geology and Equipment Performance by : Matthew Quigley
Download or read book The Stochastic Optimization of Long and Short-term Mine Production Schedules Incorporating Uncertainty in Geology and Equipment Performance written by Matthew Quigley and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Mine production scheduling consists of defining the extraction sequence and process allocation of mineralized material over some length of time. These decisions can be made at different time steps, which will entail varying objectives subject to different technical and operational constraints. Long-term mine production scheduling usually takes place at an annual scale for the entire life of mine and aims to maximize the net present value of the project while satisfying the mining and processing capacities. Short-term mine production scheduling consists of developing an extraction sequence on a shorter time scale, either months, weeks, or days. The goal is typically to maximize compliance with the production targets imposed by the long-term plan while considering more detailed operational constraints. Historically, these optimization frameworks have relied on the assumption of perfect knowledge of highly uncertain inputs. Developments in the field of stochastic mine planning have shown that incorporating uncertainty into the optimization of mine production schedules can add significant economic value while also minimizing the risk of deviating from production targets. This thesis will explore the benefits that stochastic mine planning can offer when applied to both long and short-term production scheduling problems.For the first exercise, the long-term mine production schedule of a rare earth element (REE) project is generated under geological uncertainty using a stochastic optimization framework. The uncertainty in REE grades is modelled using an efficient joint-simulation technique to preserve the strong cross-element relationships. The proposed approach avoids the use of the conventional total rare earth oxide grade. The stochastic long-term schedule is benchmarked against a deterministic schedule generated using an industry standard optimizer. The stochastic solution generates a 20% increase in expected NPV, ensures better utilization of the processing plant, and delivers a superior ore feed in terms of satisfying mineral and REE blending targets.For the second exercise, a formulation is proposed that simultaneously optimizes the short-term equipment plan and production schedule under both geological and equipment performance uncertainty. The proposed approach rectifies certain limitations of previous work in stochastic short-term planning by: incorporating a location-dependant shovel movement optimization; generating more realistic equipment performance scenarios; developing a new approach to facilitate more practical mine designs; and proposing model improvements to allow for a more efficient optimization of very large problem instances. The model is applied to a large copper mining complex and is compared to a more traditional approach, where the same formulation is implemented using averaged inputs for geology and equipment performance. The stochastic solution is more effective in mitigating the risk of deviating from tonnage targets at each processing destination, and the integration of equipment performance variability allows the stochastic optimizer to generate a block extraction sequence that is far more likely to be achieved." --
Book Synopsis Ore Reserve Estimation and Strategic Mine Planning by : Roussos Dimitrakopoulos
Download or read book Ore Reserve Estimation and Strategic Mine Planning written by Roussos Dimitrakopoulos and published by Springer. This book was released on 2015-11-15 with total page 325 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mining business faces continual risks in producing metals and raw materials under fluctuating market demand. At the same time, the greatest uncertainty driving the risk and profitability of mining investments is the geological variability of mineral deposits. This supply uncertainty affects the prediction of economic value from the initial valuation of a mining project through mine planning, design and production scheduling. This book is the first of its kind, presenting state-of-the-art stochastic simulation and optimization techniques and step-by-step case studies. Quantification of geological uncertainty through new efficient conditional simulation techniques for large deposits, integration of uncertainty to stochastic optimization formulations for design and production scheduling and the concurrent management of risk are shown to create flexibility, options and oportunities, increase asset value, cashflows and return on investment. New approaches introduced include resource/reserve risk quantification, cost-effective drilling programs, pit design and long-term production scheduling optimization with simulated orebodies, ore reserve classification, geologic risk discounting, waste managing and demand driven scheduling, risk assessment in meeting project production schedules ahead of mining, risk based optimal stope design, options valuation when mining. Applications include commodities such as gold, copper, nickel, iron ore, coal and diamonds.
Book Synopsis Advances in Applied Strategic Mine Planning by : Roussos Dimitrakopoulos
Download or read book Advances in Applied Strategic Mine Planning written by Roussos Dimitrakopoulos and published by Springer. This book was released on 2018-01-17 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a collection of papers on topics in the field of strategic mine planning, including orebody modeling, mine-planning optimization and the optimization of mining complexes. Elaborating on the state of the art in the field, it describes the latest technologies and related research as well as the applications of a range of related technologies in diverse industrial contexts.
Book Synopsis Proceedings of the 28th International Symposium on Mine Planning and Equipment Selection - MPES 2019 by : Erkan Topal
Download or read book Proceedings of the 28th International Symposium on Mine Planning and Equipment Selection - MPES 2019 written by Erkan Topal and published by Springer Nature. This book was released on 2019-11-29 with total page 515 pages. Available in PDF, EPUB and Kindle. Book excerpt: This conference proceedings presents the research papers in the field of mine planning and mining equipment including themes such as mine automation, rock mechanics, drilling, blasting, tunnelling and excavation engineering. The papers presents the recent advancement and the application of a range of technologies in the field of mining industry. It is of interest to the professionals who practice in mineral industry including but not limited to engineers, consultants, managers, academics, scientist, and government staff.
Book Synopsis Application of Efficient Frameworks for Joint Simulation of Multi-element Mineral Deposits and Stochastic Optimization of Open Pit Mine Production Scheduling by : Mario De Freitas Silva
Download or read book Application of Efficient Frameworks for Joint Simulation of Multi-element Mineral Deposits and Stochastic Optimization of Open Pit Mine Production Scheduling written by Mario De Freitas Silva and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "The optimization of open pit mine production scheduling (OPMPS) is an intricate process due to its size and uncertainty of key input parameters. Over the last decade, substantial effort has been made towards the development of new stochastic frameworks that incorporates uncertainty into the decision process. However, due to the intrinsic complexity of the mathematical programming formulation and the large size of mineral deposits, finding an exact solution for the OPMPS is likely intractable. In addition to that, modelling the joint spatial uncertainty of mineral deposits accounting for several correlated geological attributes, significantly increases the complexity of these stochastic frameworks. These observations motivate the development of new computationally efficient approaches for generating joint stochastic simulations of a deposit and for solving the OPMPS under geological uncertainty. This thesis considers both aspects in its two main parts.In the first part of this thesis, an efficient heuristic solution approach is applied and tested to the stochastic mine production scheduling of a relatively large gold mine containing about 120 thousand blocks and considering a set of fifteen geological scenarios generated stochastically. The stochastic integer programming (SIP) formulation addresses multiple processing streams and a 'grade' stockpile which adds flexibility to the specific operation by advancing the processing of highly valuable material. The solution approach tested herein, first generates an initial feasible solution by sequentially solving the stochastic OPMPS period by period and afterwards, a network flow algorithm is used to sequentially search for further improvements. In this network graph the nodes identify candidate blocks which might have their extraction either postponed or advanced, aiming for new schedule with higher values and lower risk. The results show that production schedules with low deviations from production expectations can be generated in a reasonable time for an actual mining environment.In the second part, an efficient joint simulation framework is demonstrated though an application to Vale's Puma deposit, a major nickel laterite asset in Brazil. To integrate the variability of the revolting profiles, their 'true' thicknesses are jointly simulated using min/max autocorrelation factor (MAF). The realizations serve as geological boundaries within which Ni, Co, Fe, SiO2, MgO and dry-tonnage factor (DTF) can be jointly simulated directly at block support scale. The final result is a set of equiprobable representations of the deposit that incorporates both grade and tonnage uncertainty. These simulations can be used to assess the uncertainty about key aspects of the project, such as strict control of the ore's quality that feeds the metallurgical plant. The framework explored takes advantage of the MAF and direct block simulation approaches which facilitate the joint simulation of large multi-element deposits." --
Book Synopsis Simultaneous Short-term Decision-making in Mining Complexes Integrating Geometallurgy Assisted by Production Data by : Christian Both
Download or read book Simultaneous Short-term Decision-making in Mining Complexes Integrating Geometallurgy Assisted by Production Data written by Christian Both and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "A mining complex is an integrated business of mines and downstream facilities that extracts raw materials, converts extracted materials into sellable products, and transports products to markets and customers. Conventionally, individual components of a mining complex are optimized independently of each other, which causes underperformance of the mineral value chain. Simultaneous stochastic optimization of mining complexes has shown to create strategic mine plans that increase the net present value while reducing risk of meeting production targets by incorporating geological and price uncertainty. While these developments jointly optimize strategic decisions of a mining complex, short-term planning makes weekly to monthly decisions to best meet long-term production targets and maximize value. These decisions include short-term extraction sequence, destination of materials, and downstream material flow in mining complexes. Furthermore, the optimal allocation of the mining fleet is an important aspect of short-term planning; however, the joint stochastic optimization of short-term production schedules and fleet management in mining complexes has not yet been developed. Additionally, geometallurgical properties that drive revenues, costs, and the ability to meet production targets, are not integrated in the optimization of short-term production schedules in mining complexes. This thesis expands the simultaneous stochastic optimization of mining complexes for long-term planning into a decision-making framework for short-term mine planning through the incorporation of fleet management and geometallurgical prediction models of plant performances into the short-term optimization of mining complexes, which is assisted by the utilization of collected datasets from production processes in mines and processing plants. First, a new stochastic integer programming model for short-term planning is developed that extends the simultaneous stochastic optimization of mining complexes to allow the scheduling of a heterogeneous truck fleet and shovel allocations while considering the costs and loss of production caused by shovel relocation. Next to geological uncertainty, equipment performance uncertainties related to production rates, availabilities, and truck cycle times are integrated. Next, a geometallurgical model for the prediction of ball mill throughput in mining complexes is developed which utilizes drilling penetration rates and recorded throughput rates of the operating plant. The creation of hardness proportions avoids biases introduced by the change of support and blending of non-additive geometallurgical properties. By integrating the throughput prediction model into the simultaneous stochastic optimization formulation, planned production can be achieved reliably because scheduled materials match with the predicted mill performance. The throughput prediction model is extended thereafter by including recorded measurements of ball mill power draw and particle size distributions. Since the addition of new features increases the possibilities of non-linearities, a neural network is used. The prediction of metallurgical responses of the operating plant and their incorporation into short-term stochastic production scheduling is finally extended by creating prediction models of consumption rates of reagents and consumables in a gold mining complex. With the new developments presented in this thesis, the simultaneous stochastic optimization of mining complexes can now be applied for short-term planning, modelling the operational aspects of the mining fleet and metallurgical behaviour of processing plants in greater detail. The integration of these short-term aspects leads to short-term mine plans that are more likely to align with long-term production targets while benefitting from synergistic effects that maximize the profit of the mineral value chain"--
Book Synopsis Mineral Resource Estimation by : Mario E. Rossi
Download or read book Mineral Resource Estimation written by Mario E. Rossi and published by Springer Science & Business Media. This book was released on 2013-12-21 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mineral resource estimation has changed considerably in the past 25 years: geostatistical techniques have become commonplace and continue to evolve; computational horsepower has revolutionized all facets of numerical modeling; mining and processing operations are often larger; and uncertainty quantification is becoming standard practice. Recent books focus on historical methods or details of geostatistical theory. So there is a growing need to collect and synthesize the practice of modern mineral resource estimation into a book for undergraduate students, beginning graduate students, and young geologists and engineers. It is especially fruitful that this book is written by authors with years of relevant experience performing mineral resource estimation and with years of relevant teaching experience. This comprehensive textbook and reference fills this need.
Book Synopsis Orebody Modelling and Strategic Mine Planning by : Roussos Dimitrakopoulos
Download or read book Orebody Modelling and Strategic Mine Planning written by Roussos Dimitrakopoulos and published by . This book was released on 2005 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Proceedings of the 27th International Symposium on Mine Planning and Equipment Selection - MPES 2018 by : Eleonora Widzyk-Capehart
Download or read book Proceedings of the 27th International Symposium on Mine Planning and Equipment Selection - MPES 2018 written by Eleonora Widzyk-Capehart and published by Springer. This book was released on 2019-02-21 with total page 569 pages. Available in PDF, EPUB and Kindle. Book excerpt: This proceedings book presents research papers discussing the latest developments and findings in the fields of mining, machinery, automation and environmental protection. It includes contributions from authors from over 20 countries, with backgrounds in computer science, mining engineering, technology and management, and hailing from the government, industry and academia. It is of interest to scientists, engineers, consultants and government staff who are responsible for the development and implementation of innovative approaches, techniques and technologies in the mineral industries. Covering the latest advances in fundamental research, it also appeals to academic researchers.
Author :Roussos Dimitrakopoulos Publisher :Springer Science & Business Media ISBN 13 :9401108242 Total Pages :513 pages Book Rating :4.4/5 (11 download)
Book Synopsis Geostatistics for the Next Century by : Roussos Dimitrakopoulos
Download or read book Geostatistics for the Next Century written by Roussos Dimitrakopoulos and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 513 pages. Available in PDF, EPUB and Kindle. Book excerpt: To honour the remarkable contribution of Michel David in the inception, establishment and development of Geostatistics, and to promote the essence of his work, an international Forum entitled Geostatistics for the Next Century was convened in Montreal in June 1993. In order to enhance communication and stimulate geostatistical innovation, research and development, the Forum brought together world leading researchers and practitioners from five continents, who discussed-debated current problems, new technologies and futuristic ideas. This volume contains selected peer-reviewed papers from the Forum, together with comments by participants and replies by authors. Although difficult to capture the spontaneity and range of a debate, comments and replies should further assist in the promotion of ideas, dialogue and criticism, and are consistent with the spirit of the Forum. The contents of this volume are organized following the Forum's thematic sessions. The role of theme sessions was not only to stress important topics of tOday but in addition, to emphasize common ground held among diverse areas of geostatistical work and the need to strengthen communication between these areas. For this reason, any given section of this book may include papers from theory to applications, in mining, petroleum, environment, geohydrology, image processing.
Book Synopsis Applied Geostatistics with SGeMS by : Nicolas Remy
Download or read book Applied Geostatistics with SGeMS written by Nicolas Remy and published by Cambridge University Press. This book was released on 2011-04-14 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Stanford Geostatistical Modeling Software (SGeMS) is an open-source computer package for solving problems involving spatially related variables. It provides geostatistics practitioners with a user-friendly interface, an interactive 3-D visualization, and a wide selection of algorithms. This practical book provides a step-by-step guide to using SGeMS algorithms. It explains the underlying theory, demonstrates their implementation, discusses their potential limitations, and helps the user make an informed decision about the choice of one algorithm over another. Users can complete complex tasks using the embedded scripting language, and new algorithms can be developed and integrated through the SGeMS plug-in mechanism. SGeMS was the first software to provide algorithms for multiple-point statistics, and the book presents a discussion of the corresponding theory and applications. Incorporating the full SGeMS software (now available from www.cambridge.org/9781107403246), this book is a useful user-guide for Earth Science graduates and researchers, as well as practitioners of environmental mining and petroleum engineering.
Book Synopsis Stochastic Short-term Production Scheduling Accounting for Fleet Allocation, Operational Considerations, Blending Restrictions and Future Multi-element Ore Control Data by : Martha Villalba Matamoros
Download or read book Stochastic Short-term Production Scheduling Accounting for Fleet Allocation, Operational Considerations, Blending Restrictions and Future Multi-element Ore Control Data written by Martha Villalba Matamoros and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Mine production scheduling may be long-term or short-term based on the time period considered and the final objective. The optimization goal of short-term production scheduling is to minimize the mining cost expected from a mine while satisfying operational constraints, such as mining slope, grade blending, metal production, mining capacity and processing capacity; however some parameters may be uncertain, such as metal quality and fleet parameters. Traditional short-term production planning is carried out by two sequential optimizations, production schedule is defined at the first step and the available fleet is evaluated for this schedule as a second step, however; the fleet availability, hauling time and mining considerations do not influence the schedule decision. In addition, the fleet optimization algorithms do not consider uncertainty in their parameters and do not take into account the local mineralization of the deposit because a single possibly misleading total aggregated block tonnage is linked to each sector to be mined. The local mineralization or local scale variability between blocks assists in the blending process and metal quality control; however, the traditional short-term production scheduling is based on exploration drilling or a sparse data ore body model, while in practice grade control data or close spacing blasthole drilling classify the material as ore and waste because their short-scale information is not available at the time of the monthly short-term planning. The local variability is relevant in the short-term production scheduling to define the destination of the material.The short-term mine production scheduling in this thesis is developed as a single formulation where mining considerations, production constraints, uncertainty in the orebody metal quantity, as well as fleet parameters, are evaluated together to define a well informed sequence of mining that results in high performance at the mine operation. The formulation is implemented at a multi-element iron mine and the resulting monthly schedules show lower cost, minable patterns and, efficient fleet allocation, that ensures a higher and less variable utilization of the fleet over the conventional schedule approach.Uninformed and ultimately costly decisions can be taken because of imperfect geological knowledge or information effect. The orebody uncertainty may be updated by simulated future ore control data to account for local scale grade variability, and the information used to discriminate ore and waste in practice. Multi-element orebody uncertainty models are updated based on the correlation of exploration data and past ore control data, this orebody uncertainty is then used to optimize the short-term production scheduling that leads to better performance in terms of matching ore quality targets and delivering recoverable reserves." --
Book Synopsis Stochastic Orebody Modelling and Stochastic Long-term Production Sheduling for an Iron Ore Deposit in Northern Quebec by : Maria Vallejo Garcia
Download or read book Stochastic Orebody Modelling and Stochastic Long-term Production Sheduling for an Iron Ore Deposit in Northern Quebec written by Maria Vallejo Garcia and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "The process of mine planning, from prospection of orebody deposits defining its extension, location and value, until obtaining minerals and their extraction sequence in time, requires mathematical optimization to determine the size and grade (grades) of the deposit and finally define a proper mine schedule to obtain the maximum earnings from it, at the lowest possible cost, in order to fulfill the business targets. In general, a mining project passes through a set of stages in order to evaluate its viability. One of these stages is the "feasibility stage" where the gathered information from mining studies is used to determine the economics and practical aspects of the ore deposit. This identifies, early on, whether further investment in estimation and engineering studies are required, and identifies areas for further work and development. The KéMag iron ore deposit owned by New Millennium Limited in northern Quebec, Canada, is in feasibility stage. The KéMag iron ore deposit is a taconite type, where the iron content is present as finely dispersed magnetite between 20 and 35 % iron (Fe) in a sedimentary rock interlayered with quartz, chert, and carbonate. This thesis focuses on a set of methodologies to develop a whole process of stochastic orebody modelling and stochastic strategic mine planning for the KéMag deposit, aiming to generate a modelling and optimization methodology that integrates geological uncertainty and manages risk in the mine schedule. This mathematical framework has been successfully implemented in the last two decades allowing modelling and integration of geological uncertainty to mine design, production scheduling and valuation of mining projects. From the application, several cases have shown an increment on the value of the production schedules up to 25%, and a reduction of deviation from production targets from 9% to 0.2%. For the KéMag deposit a set of fifteen realizations of nine lithological units (layers) were simulated using WAVESIM which is a multiple point simulation method combined to an image compression procedure to allow faster simulations. The orebody simulations obtained through WAVESIM serve as geological boundaries to integrate the variability of the four grades of interest using DBMAFSIM this method allows the simulation of correlated variables directly at block support using min/max autocorrelation factors MAF. The final result is a series of equally probable representations of the deposit that incorporate both grade and tonnage uncertainty. These simulations of the KéMag deposit were validated in terms of histograms, variograms (low order statistics) and high-order statistics through 3rd order cumulants maps for the boundary limits only. Geological uncertainty can then, be managed by directly incorporating stochastic simulations within the mine scheduling framework. To achieve this, one flexible method for long-term production scheduling based on Stochastic Integer Programming (SIP) was applied with an acceleration methodology based on a heuristic algorithm called Topological Sort Algorithm (TSA) to reduce the computational time required to solve the problem of production scheduling. The result of the stochastic mine planning framework is a single schedule robust enough to account for geological uncertainty of the KéMag deposit giving valuable information for the conceptual stage of the project, in terms of silica content, iron production and expected cash flows per year." --
Book Synopsis Advanced Analytics in Mining Engineering by : Ali Soofastaei
Download or read book Advanced Analytics in Mining Engineering written by Ali Soofastaei and published by Springer Nature. This book was released on 2022-02-23 with total page 746 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, Dr. Soofastaei and his colleagues reveal how all mining managers can effectively deploy advanced analytics in their day-to-day operations- one business decision at a time. Most mining companies have a massive amount of data at their disposal. However, they cannot use the stored data in any meaningful way. The powerful new business tool-advanced analytics enables many mining companies to aggressively leverage their data in key business decisions and processes with impressive results. From statistical analysis to machine learning and artificial intelligence, the authors show how many analytical tools can improve decisions about everything in the mine value chain, from exploration to marketing. Combining the science of advanced analytics with the mining industrial business solutions, introduce the “Advanced Analytics in Mining Engineering Book” as a practical road map and tools for unleashing the potential buried in your company’s data. The book is aimed at providing mining executives, managers, and research and development teams with an understanding of the business value and applicability of different analytic approaches and helping data analytics leads by giving them a business framework in which to assess the value, cost, and risk of potential analytical solutions. In addition, the book will provide the next generation of miners – undergraduate and graduate IT and mining engineering students – with an understanding of data analytics applied to the mining industry. By providing a book with chapters structured in line with the mining value chain, we will provide a clear, enterprise-level view of where and how advanced data analytics can best be applied. This book highlights the potential to interconnect activities in the mining enterprise better. Furthermore, the book explores the opportunities for optimization and increased productivity offered by better interoperability along the mining value chain – in line with the emerging vision of creating a digital mine with much-enhanced capabilities for modeling, simulation, and the use of digital twins – in line with leading “digital” industries.
Book Synopsis Geostatistics for Natural Resources Evaluation by : Pierre Goovaerts
Download or read book Geostatistics for Natural Resources Evaluation written by Pierre Goovaerts and published by Oxford University Press, USA. This book was released on 1997 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: This text provides an advanced introduction to the theory and applications of geostatistics, including tools for description, modeling spatial continuity, spatial prediction, assessment of local uncertainty, and stochastic simulation.
Book Synopsis Mine Planning and Equipment Selection by : Carsten Drebenstedt
Download or read book Mine Planning and Equipment Selection written by Carsten Drebenstedt and published by Springer Science & Business Media. This book was released on 2013-10-16 with total page 1464 pages. Available in PDF, EPUB and Kindle. Book excerpt: This edited volume includes all papers presented at the 22nd International Conference on Mine Planning and Equipment Selection (MPES), Dresden, Germany, 2013. Mineral Resources are needed for almost all processes of modern life, whilst the mining industry is facing strict requirements regarding efficiency and sustainability. The research papers in this volume deal with the latest developments and research results in the fields of mining, machinery, automatization and environment protection.
