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By Juan Mayta

Dada la situación actual y escenario post COVID-19, es fundamental adoptar estrategias de Gestión Colaborativa e Integrada de Proyectos, este artículo es el resultado de la aplicación de Virtual Design Construction (VDC) y Building Information Modelling (BIM) en la etapa de Diseño de un proyecto de reemplazo de Equipos Críticos en la Parada de una Planta concentradora de Cobre (Cu) para Sociedad Minera El Brocal, operación minera ubicada en Cerro de Pasco, Perú.

Sep 29, 2023

By J. Paraszczak

Underground metal mining involves many challenges. Economic slowdown, tough international competition and sometimes volatile metal prices put constant pressure on mine operators to increase productivity and to reduce production cost. At the same time, countries such as Canada, the United States and Australia are experiencing skilled labor shortages that might even stall development of certain mine projects. Furthermore, some stages of underground production take place in particularly hazardous environments where the safety and health of miners is at risk. Automation of some processes in underground mining is one of the promising avenues to alleviate some of these problems. Loading and haulage are among the most critical operations and areas where implementation of autonomous vehicles has been targeted. However, although health and safety issues are a primary driver to opt for automation, the latter should ensure an acceptable level of productivity and pro?tability. With this in mind, this article focuses on the factors affecting operational effectiveness of autonomous underground loading and haulage equipment and the means to maximize it.

By J. Paraszczak

Application of teleoperated and automated (or ?autonomous?) mobile equipment in underground metal mines is a promising avenue for overcoming some of the challenges facing mine operators. These include, but are not limited to, the issues related to safety and health of underground workers, better use of the shift time leading to increased productivity, skilled manpower shortages, and remoteness of some mine sites. Autonomous load-haul-dump machines and trucks offer several benefits over man-operated ones, but their use at their full capacity is a challenging and complex task. This paper makes an overview of commercially available equipment and systems and their applications. It examines factors affecting adversely availability, utilization, and production efficiency of autonomous vehicles and compares them to conventional man-operated machines. Technical and operational aspects are discussed and their criticality is analyzed. Based on that, recommendations concerning means and measures that may help raise operational effectiveness are given. It is stressed that due to a scarcity of publicly available information on the performance and cost of autonomous loading and haulage operations, more field studies and in-depth analysis are needed.

Feb 23, 2014

By Gil Ribeiro Vilela Neto

Na busca por se tornar cada vez mais sustentável, a indústria mineral vem recorrendo às soluções tecnológicas que minimizem o impacto ambiental gerado pela disposição dos rejeitos resultantes dos processos de beneficiamento de minérios. Neste cenário, umas das soluções é a aplicação de tecnologias de separação sólido-líquido com o objetivo de maximizar o desaguamento dos rejeitos e, consequentemente, diminuir o volume ocupado por eles quando dispostos e aumentar a recirculação de água. Este trabalho tem como objetivo, determinar a influência da concentração de sólidos em polpas de rejeitos denominados de “lamas” no desempenho do espessamento e a determinação da concentração de sólidos ótima para atingir o melhor desempenho do espessador.

Aug 16, 2017

By K. Kim

"All milling operations would like to achieve the best possible recovery in combination with the highest achievable throughput. Unfortunately, many operations have problems with low recovery, low throughput or both. In the majority of these cases investigated by the author, the solutions to improve recovery and throughput were simple. The solutions did not include implementation of new technology or major capital, but rather a return to fundamentals. In most cases, problems occurred because the operation was not following their own operating procedures, because the design of the circuit was changed without adequate change management or understanding of the implications of changes, or because basic metallurgical measurements and control were not taken or ignored. In this paper, examples of these problems and their solutions derived from long and varied experience will be discussed. The objective of this presentation is to provide the milling operator with practical and readily implementable solutions to common milling issues to improve throughput and recovery.INTRODUCTION Mill operations can be evaluated by many operating parameters, but the two best indicators are recovery and throughput. These two parameters summarize the wellbeing of an operation. The grade to the mill is also a good indicator, but this is usually controlled by the mine. The best recovery and throughput are achieved through a team work involving operators, maintenance workers and metallurgical staff. The milling operations include many unit operations, such as crushing, grinding, flotation, leaching, carbon in leach, Merrill Crowe, roaster, autoclave and refinery. The tools available to the operations are plant design, process measurements, assays, metallurgical balance, and operating strategy. Twelve real life examples of improvements of recovery and throughput are presented in this paper. EXAMPLE 1: CRUSHING CIRCUIT WITHOUT FINE ORE BIN At this operation plant throughput could not be maintained at a high rate because feed to the mill became coarse during the day. The cone crusher was feeding the ball mill directly. As the day wore on, the gap on the cone crusher would slowly increase, which would cause the product size to increase. This would increase the re-circulating load on the ball mill. The throughput would decrease accordingly. Furthermore, the throughput would decrease more with high frequency of maintenance on the cone crusher."

Jan 1, 2019

By J. A. Zimmer, M. S. Hillis, D. Moredock, J. A. Organiscak, A. B. Cecala

Enclosed cabs have been used on surface mining equipment for many years to protect equipment operators from health and safety hazards. The surface mining and quarrying process is a highly mechanized process that generates large quantities of respirable dust. Due to economic factors, more older mining equipment is being used today than in years past. With this older equipment, it is common to observe deterioration of many components on the enclosed cabs, which greatly reduce their protection effectiveness. NIOSH has performed a number of different field studies, as well as a comprehensive laboratory study, evaluating various factors and parameters regarding enclosed cabs. NIOSH has recently completed a cooperative research effort to evaluate the effectiveness of a newly designed unidirectional powered precleaner, filter and pressurizer that brings clean filtered air in at the roof of the cab and extracts all recirculated air near the floor. This research effort provided another example of the enhancement in air quality that can be achieved in an enclosed cab from the implementation of an improved filtration system and by establishing positive pressurization from increased intake air volume and sealing the cab. This testing showed a significant reduction in respirable dust levels in the enclosed cab when comparing baseline versus post-testing results. Since dust levels were similar near the roof and floor of the cab during post-testing, the unidirectional flow pattern did not appear to significantly improve the performance over the conventional design in this study.

Jan 1, 2009

By A. B. Cecala

Enclosed cabs have been used on surface mining equipment for many years to protect equipment operators from health and safety hazards. The surface mining and quarrying process is a highly mechanized process that generates large quantities of respirable dust. Due to economic factors, more older mining equipment is being used today than in years past. With this older equipment, it is common to observe deterioration of many components on the enclosed cabs which greatly reduce their protection effectiveness. NIOSH has performed a number of different field studies, as well as a comprehensive laboratory study evaluating various factors and parameters regarding enclosed cabs. NIOSH has recently completed a cooperative research effort with Sy-Klone International and Vulcan Materials Company to evaluate the effectiveness of a newly designed uni-directional filtration and pressurization system that brings all the clean filtered air in at the roof of the cab and extracts all recirculated air near the floor. This design provides the highest air quality to the equipment operator. Testing on this new system showed an almost 10-fold reduction in respirable dust inside the enclosed cab. The uni-directional design is easy to incorporate and should be considered for all new and retrofit systems in surface mining equipment.

Jan 1, 2009

By Pat McLaughlin

Blast design in the construction industry has often been based on past practice or powder factors. This is to some extent understandable, since construction projects do not have the longevity of mining or quarrying operations and therefore have less opportunity to pursue potential improvements. The main concern of the operator is whether or not the technique will work, and at what cost to the downstream processes. Time, not long term savings, is of the essence.

Jan 1, 1994

By J. Evans

Including: Tailings thickeners, CCD?s, paste thickeners, HI-rate thickeners, lamella thickeners, high compression thickeners, clarifiers etc. Flocculant dosing control for mining thickeners and clarifiers is influenced by a number of process factors. 1. Flow rate into the thickener or clarifier a) As the flow rate increases into the thickener or clarifier ?retention time? decreases which causes a greater affect hydraulically on the settling solids. So as the flow rate increases it will generally mean an increase in flocculant dosing rate. b) As the flow rate decreases into the thickener or clarifier the retention time increases which reduces the hydraulic affect on settling, improving settling rates. This will generally mean that as the flow rate decreases, we will decrease the flocculant dose rate.

Jan 1, 2011

By C. -G. Berg, J. T. Tuominen

Since the beginning of the 20th century, energy efficiency in copper smelting has been improved by a factor of 30 as a result of adopting autogenous smelting processes with more and more efficient waste heat recovery systems, increasing use of oxygen enrichment and countless smaller improvements. Nevertheless, energy in the form of electricity and fuels continues to be the biggest contributor to smelter operating cost. Metallurgists around the world are under constant pressure to find ways to save those precious megajoules wherever they can. One area that is often neglected is the removal of water contained in concentrates. Copper flotation concentrates, as delivered to a smelter, typically contain some 8–12% moisture. This moisture must be removed and the only way to do this is by evaporation, which consumes a lot of energy. Several studies have shown that the most efficient way of removing this moisture is to use a steam- heated indirect dryer—the least efficient way being the feeding of wet concentrate directly into a smelting furnace. Even in the most efficient smelters that employ modern steam drying, the energy needed to remove the moisture from the concentrates constitutes over 15% of the total energy consumption of a smelter – acid plant complex. The major steps that have been taken in the past to lower the energy consumption of moisture removal are the use of drying in general and the adoption of steam drying. The energy efficiency of concentrate drying has been improved by 25% over the last 20 years. The latest giant leap in this area, the Kumera Heat Recovery Dryer, is the result of Kumera’s long-term development in improving the efficiency of concentrate drying. The Heat Recovery Dryer is a novel application of steam drying that uses the waste heat from dryer exhaust gas for drying concentrates, thus, cutting the energy consumption by a further 30%. This paper discusses energy consumption in copper smelting in general and analyzes the energy consumption of concentrate drying in detail. Different dryer types are compared especially from the perspectives of energy consumption and environmental emissions. Applicability of different energy sources for drying is evaluated and discussed. The principle of the Kumera Heat Recovery Dryer is presented along with results from extensive continuous pilot plant tests. Potential applications and the feasibility of Kumera Heat Recovery Drying technology are discussed.

Jan 1, 2019

By J. A. Abols, P. M. Grady

Recovery via gravity is one of the oldest mineral processing methods available. Unfortunately, the use of gravity techniques for gold recovery has been in decline for the past century as more effective chemical processes such as flotation and leach/CIP have been developed. Recently, with the push towards more sustainable environmental outcomes, the benefits of gravity separation have become more apparent. While gravity as a unit process is not usually capable of achieving as high a recovery as flotation or whole ore cyanidation, a combination of gravity devices alone or in conjunction with these processes can offer significant advantages to the operator. This paper reviews the range of gravity devices available, their application and the results that can be achieved by maximizing gravity through the use of a combination of gravity recovery devices. Three case studies are provided.

Jan 1, 2005

By M. Dworzanowski

The physical beneficiation of iron ore that has a wide particle-size distribution is problematic, regardless of the process applied, whether dense medium separation, gravity concentration, magnetic separation, or flotation. The problem of particle size is further compounded when there is a significant -10 µm fraction. Generally the approach to a wide particle-size distribution is to split into narrower size ranges and treat each separately. More often than not the -10 µm fraction is not treated but discarded. This approach results in a more complicated and expensive flow sheet and the loss of any potential value in the -10 µm fraction. Wet high-intensity magnetic separation (WHIMS) bench-scale test work was conducted on a haematite-rich material with a particle size of -200 µm. What made this material different was that it contained a 60% -10 µm fraction, hence discarding the -10 µm material was not an option. The objective of the test work was to determine how to maximize the recovery of the haematite across the full particle size range. Given the unusual particle size distribution, it was concluded that WHIMS would be the only practical beneficiation route. The -200 +10 µm and -10 µm fractions were treated separately and together under varying WHIMS conditions. For a given concentrate grade, the mass yield obtained was greater when the total particle-size distribution was treated. The inferred optimum conditions, using the same material, were tested on a pilot-scale WHIMS and similar results were obtained.

Jan 1, 2014

By I. Mikov

Established in the 60-ies, the Zlatna Panega quarry is a cement raw materials quarry supplying 95% of the needs of the Zlatna Panega Cement Plant with limestone, marl and other silica-aluminates. The two major types of raw materials are formed by accordingly dipping strata of Upper Jurassic limestones and lower Cretaceous marls. Between them there is a ?transition-zone? or ?contact-zone? of a high-silica content layer, about 5-m thick, defined as ?flint? by investigations including spot sampling throughout the quarry. For many years this ?contact-zone? layer was neglected due its negligible thickness. Further, with the increasing demand on the quality of the raw materials feed to the Plant and the focus on variability of the chemical and mineralogical components, it was decided not to mine any of the parts of the quarry contaminated by this material, for about three years. The latter had an impact on the availability of operating benches that could result in a substantial decrease in the total recoverable re-serves of Zlatna Panega, particularly with respect to marls. There were considerations for resorting to a partial, selective excavation of the quarry pit with a reduced lifetime for the lime-stones and re-opening of an other (currently in-active) marl quarry at a distance of 6 Km from the Plant. The Quarry Team of the Zlatna Panega quarry was assigned to study the problem. The ?contact? layer was duly confirmed with systematic geological (including mineralogy) studies, statistical analysis of available data, surface sampling and shallow exploration drills, resulted into distinguishing a third type of reserves and their credible subsurface delineation by means of geological 3-D modeling and quarry design. A new quarry design was finally elaborated with a view of providing flexibility in mining, utilization of the total volume of all available reserves and maximizing the mine life of Zlatna Panega quarry. An industrial test took place in December 2005, by using the contaminated parts of the quarry (co-mining of the ?contact-zone? materials) at a contribution of 15-20% in the raw materials mix, as dictated by their contribution in the total recoverable resources of the quarry. The purpose was to investigate the viability of this solution ? in line with improved quarry planning ? without compromising the quality of cement production and the efficiency of Plant Operations. Results were overall successful.

Jan 1, 2006

By Aris Tambunan, Nella Lubis, Nurafrianti Saala, Komang Widhiayanto, Herry Saputra, Rudolf Sitorus

Maximizing mining recovery rates and minimizing ore loss are pivotal objectives for economic efficiency and operational effectiveness. This study explores methods to address these imperatives by enhancing ore production and recovery through improved blasting techniques and spillage control in the Martabe Gold Mine Project in North Sumatra Province, Indonesia. Between 2018 and 2021, the average mining recovery rate stood at 93%, resulting in a potential annual ore loss of 7% and a potential quarterly financial impact of close to $2 million. Maintaining and enhancing mining recovery became crucial, with a planned 30% increase in total material movement for 2022. The mining recovery target for 2022 was set at 96% based on best achievement historical data from 2021 to increase ore tonnage by 203 KTon per annum. To achieve the primary objective of increasing ore production by improving mining recovery, the study focused on predicting and controlling the movement of blasted ore to reduce spillage and enhancing the grade control model to reflect actual conditions post-blasting. Several alternative solutions were explored, primarily emphasizing drilling and blasting activities. Essential methods included capturing the actual blasting movement to adjust the ore block based on blasting design data and post-blasting muckpile topography. This approach minimizes ore loss by providing output as ore block adjustment based on post-blast movement data. In addition, the tie-up design was adjusted to control ore spillage outside the pit ridge. The implementation of these methods yielded significant improvements. Adjusting the ore block based on actual blasting movement contributed $1,545,764 in benefits. Controlling ore spillage outside the pit ridge achieved a 10% reduction in spillage, contributing $79,184 in benefits. These enhancements successfully met the 2022 mining recovery target of 96%, marking a 3% increase from 2021. Consequently, ore loss was reduced by 178 KTon throughout 2022, resulting in a financial impact of $7.3 million. The study underscores the significance of precise blasting techniques and effective spillage control in enhancing mining recovery rates.

Jan 21, 2025

Since 1992 the Grasberg Mine, located in the remote regions of Indonesia, has utilized the Modular Mining System. Over the last several years, major steps have been taken to maximize this productivity enhancement system. These steps include; the Automated Lineup, the Linear Program upgrade, tracking of Mean Time Between Failure, a MEDS system interface, a VMIS system interface, and implementation of the new Graphical Operator Interface Console with Global Positioning, This application of new technology and innovation has lead to improved performance, understanding and reporting, as well as the quality of the Indonesian Engineers. These efforts have contributed 10 Grasberg achieving one of the lowest mining costs in the copper industry.

Jan 1, 1998

By Barara Rose

Presentation Outline ?Introduction of BMS ?Resource Integration Process ?Methodologies ?Tools ?Case Studies ?Zone 01 : 725 SOZ ?Zone 16/17 : 1000 NRP ?Conclusions

Oct 1, 2010

By Jeffrey D. Eisenman

FRP is a proven material for the solvent extraction processes of copper production. There is a history of successful applications of FRP piping and equipment in hydrometallurgical processing. The performance of FRP equipment has not always been consistent, but at no fault of the material. Its non-metal attributes and behavior vary from those of more typical materials of construction, such as steel and alloys. FRP is a mainstay material in many areas of solvent extraction and electrowinning and yet not well understood by all. We will discuss the critical concerns, which are key to reliable performance of FRP systems. This paper will include discussion of key elements, which are fundamental to reliable FRP piping design and considered best practices. Essential design and construction considerations to maximize reliable service life of FRP equipment, such as thickeners and process vessels, used in copper extraction and processing, will be discussed. Additionally, we will expose potential pitfalls and share lessons learned from previous copper processing plant projects, which can aid and impact other copper processing projects to ensure best system performance and reliability. INTRODUCTION The corrosion resistant attributes of fiberglass reinforced plastics (FRP) make it an attractive and cost effective material of construction in corrosive service applications that are found in copper processing. FRP is used all over the processing plant in seawater, brine and sulfuric acid services where the corrosive nature of these services would challenge most ferrous materials and coatings. FRP is a fully customizable material to meet the specific needs of each service and process. FRP piping and equipment can be found throughout the hydrometallurgical process, in the acid plant, desalination, leaching processes, solvent extraction and electrowinning to name a few. Beyond its superior corrosion resistant characteristics, FRP can be made abrasion resistant by introducing particulate additives into the resin, such as silicon carbide and alumina oxide. Because many of these services have combustible organic elements in the flow streams with accompanying safety concerns, the linings can be made conductive with carbon fibers to dissipate static charges that might collect on the surface of the equipment otherwise. Further, FRP can be made flame retardant as well, where flammability may be of concern.

Jan 1, 2019

By Collin Bartlett, H. Storch

"Modern metallurgical processes operating with oxygen enriched air, such as the Outotec Flash Smelter and Flash Converter, generate very concentrated SO2 off-gas, which in combination with Outotec sulphuric acid plant technology allows the production of high pressure steam to be used for power generation. Outotec combines well proven technology of sulphur burning plants for this purpose with metallurgical plants.The application of Outotec’s proven LURECTM process enables processing of SO2 gas of up to 25 vol.-%. This process maximizes the energy recovery from the SO2 oxidation at a suitable high temperature level which can be turned into high pressure steam. The application of the Outotec HEROSTM heat recovery system enables the generation of low pressure steam from the absorption energy released at the intermediate absorption step. Additionally, energy is also recovered in the acid coolers for boiler feedwater pre-heating.The concept of integration of high and low pressure steam in combination with the pressurized operation of the boiler feedwater deaerator, thus heating up the boiler feed water to temperatures around 160…170°C, enables indirect transfer of low pressure steam (for deaerator operation) into more valuable high pressure steam, which improves the degree of heat recovery. This is the characteristic of Outotec’s HEROS+TM process.The increased generation of high pressure steam will in turn enable the generation of more electricity when compared to a standard traditional sulphuric acid process."

Jan 1, 2014

By Kevin Gunesch

In the current difficult financial markets, only the best projects will advance to the next phases of development due to limited funding. Projects are consistently being evaluated by their initial Capital Expenditure (CapEx), Net Present Value (NPV), and Internal Rate of Return (IRR). Optimizing these parameters is the best way to gain market interest. Global Resource Engineering LTD (GRE) completed an optimization study for a silver-lead-zinc project in Peru. In this sense, the objective of the study was to minimize the project initial Capital Expenditure while maximizing the Net Present Value and Internal Rate of Return. GRE accomplished this goal by completing a series of tradeoff studies for the project and combining them through the use of a multi-scenario deterministic model to find the most economic scenario.

Oct 21, 2015

By T. Gupta, T. Ghosh

Rare earth elements (REEs) and their compounds are essential in a multitude of mundane and sophisticated applications such as renewable energy technologies, catalysts, medicine, and defense applications. The global supply deficit could be attributed to the destabilization of REE market that has, as a result, incentivized indigenous production of REEs. Cost-effective and environmentally benign opportunities are being explored for the production of REEs from non-conventional mineral sources including coal and coal by-products to stabilize the supply chain. Coal from Healy coal mine and Wishbone Hill deposits in Alaska have been quantified for REEs and were found to possess elevated total REE concentrations as compared to world average levels (60– 70 ppm). The objective of the study was to concentrate the REEs in the froth phase by froth-flotation of the fine size fraction (< 75 μm). A Box-Behnken design of experiment was employed to ascertain the main and interaction effects of operational parameters on response variable by analyzing 3D response surfaces. Experiments were carried out to maximize REE recovery and concentration by modeling and optimization of three operating variables (frother dosage, pulp density (% solids), and collector dosage). Based on the results, the optimum flotation conditions for maximum recovery at an elevated concentration of REEs in the froth fraction was obtained at 4.2% solids and 32.7 ppm of frother dosage for Healy sample and 10% solids and 37.9 ppm of frother dosage for Wishbone Hill coal sample. The quadratic relationship between the input and response variable was found to be independent of collector dosage suggesting good surface hydrophobicity and floatability of the two coal samples.