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By P J. Jacobs

FORACO is the third-largest global drilling services company, and recently celebrated its 50th anniversary. The company’s historical roots are in French-speaking West Africa, delivering hydrogeological drilling services to resource companies, villages and regional centres. Today, FORACO operates over 300 drill rigs in more than 20 countries.The Asia Pacific region of FORACO runs a fleet of 37 late model drilling rigs servicing the diamond drilling, reverse circulation, coal, coal seam gas and hydro drilling sectors.FORACO Australia has extensive experience delivering large diameter coring (LDC) samples to the resource community. In the past three years, the company has been involved in six 8? coring projects in a variety of geographies and geologies, including iron ore, coal and uranium. FORACO has developed proprietary equipment and techniques to deliver cost-effective LDC samples with outstanding core recovery.The FORACO LDC sampling system is hands free, with mechanised rod and corebarrel handing to minimise the risk of manual handling injuries. Sample volumes are six times PQ (the common industry standard for large core samples), with core recoveries consistently above 96 per cent in extremely difficult formations.Eight inch coring is a conventional coring system suited to hole depths up to 150 m. For deeper applications, FORACO has recently invested over $4 M in a 6? wireline coring system capable of achieving depths of 300 m.CITATION:Jacobs, P J, 2014. Large diameter core sampling, in Proceedings Sampling 2014 , pp 71–76 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 29, 2014

By Chris Normand, Paul Volpe, Eric Wey, Howard Perko, Burt Ogilvie, Patrick Murray

"A refinery expansion project for Marathon Petroleum Company in Southern Louisiana required existing medium to large pipe racks to be expanded for additional capacity. Foundation modifications were necessary in order to add levels to the existing pipe racks. New piles were added and existing pile cap foundations were expanded. Several different pile types were considered. Custom designed large diameter helical piles were chosen, because they can be installed quickly with low overhead restrictions, produce minimal soil spoils, and are cost effective. The load capacity required for piles was higher than typical, off-the-shelf helical piles. In particular, the lateral load capacity demand was high due to wind loads of a hurricane prone region. Methods used to design and size helical piles are summarized including capacity to torque ratio estimation for composite helical piles. Pile load testing was performed in order to confirm design capacities of the helical piles under axial and lateral loading. Measured axial and lateral deflections compared well with predicted values. This case history evaluates the effectiveness of modern helical pile design methods within the context of a real and practical example.INTRODUCTIONAs the capacity of modern installation equipment increases, large-diameter helical piles are being used to support higher loads in more diverse applications. Currently, large-diameter high-capacity helical piles are used for electrical power transmission, power generation, high-rise buildings, bridges, and industrial applications. This case study regards a 2.5-mile pipe rack modification project within an existing refinery. One of the many challenges for engineering and construction of refinery revamp projects is determining how to effectively expand the capacity of existing foundations for additional equipment, piping, and other facilities. Custom designed large-diameter helical piles provided an effective solution to the challenges faced when expanding the capacity of existing pipe racks."

Jan 1, 2017

By Charles K. Presley

This paper deals with drilling large diameter shafts for the mining and construction industry with diameters in excess of 3 feet to more than 20 feet in diameter. It discusses appropriate applications of the rotary drill method, linings for large diameter shafts, circulation systems,, and the limitations of the method. Each specific rotary drill method is determined by the geology of the area, the depth to be drilled and the formation fluids encountered. Shaft lining or casing must be improved to result in lighter weight, higher strength and lower cost. All phases of rotary drilling equipment must be improved to drill shafts in excess of 10 feet in diameter. As these goals are reached, more shafts of large diameter will be drilled by the rotary method for the mining and construction industry.

Jan 1, 1967

By D. R. Zeni

Current mine development requires the safe, 'expedient, economical construction of vertical shafts for ventilation and access in diverse ground conditions. Advancements in large diameter shaft drilling have lead to exceptional mechanical refinements of shaft drilling technology. The author traces the history of the equipment and methods employed by the large diameter shaft drilling industry and explores likely paths of future development. A few case histories are cited to illustrate the adaptability of shaft drilling as a versatile tool for advanced worldwide mining operations. Safety, schedules, cost, environmental impact, and capability are discussed to assist the mining engineer in the investigation of feasible projects.

Jan 1, 1994

By James P. Bowersox

Modem mineral processing plants handle large amounts of ore and produce large tailing streams. Plant performance can be optimized when the water is quickly recovered with a thickener. The caisson thickener was developed to overcome process and mechanical problems with the conventional traction and center column units. The caisson is a hollow center column that serves as a pump house. The rake arm structure is supported by a hydrostatic bearing which sits on top of the caisson. The caisson thickener with a hydrostatic bearing has operated for many years in several mineral processing applications.

Jan 1, 1981

By D. Govender

In recent years, economies of scale have continued to drive copper projects to larger throughputs to offset depleting lower grade resources. A decade ago, there were only a small number of projects that stretched beyond 100 kt/d (110,000 stpd) throughput rates. Today, and moving forward, virtually all the major copper projects are sized beyond this, with throughput rates up to 250 kt/d (275,000 stpd) now under evaluation for a number of key projects in Chile and Peru. This paper explores the development from the 160 m3 (5,650 cu ft) flotation cells, through to the 257 m3 (9,076 cu ft) cells and to the current 660 m3 (23,380 cu ft) machines. The contributions of specific copper concentrators to this growth phase are reviewed in this article. The historical basis of flotation machine scale-up is also briefly discussed. Metallurgical results as well as layout, maintenance and operational aspects are highlighted.

Feb 1, 2014

By C. Horstmann, D. Andreo, G. Barthold

"The concept of large single line grinding circuits provides a valid answer in project feasibility studies by reducing capital investment requirements compared to parallel lines for the same plant throughput rates. The benefits of this concept are reflected as well on the operational aspects, in terms of higher and greater process stability, and reduced operational costs mainly due to the associated lower maintenance expenditures. However, concerns exist in the minerals industry on whether large single line grinding could reduce the overall concentrator plant availability. The mechanical design and integrity, the mill and gearless mill drive integration, as well as assets management aspects of this type of equipment are the key to guarantee successful availability records. Together with an overview of the added value provided by large single line grinding circuits, this paper focuses on risk mitigation strategies during mill and gearless mill drive integration, as well as on the design of the equipment itself, for the key aspects which could put at risk the operations availability.INTRODUCTIONDespite a large long term demand for commodities, the mining industry has never faced complex challenges as it is doing today. Decreasing high-quality and accessible deposits, declining ore grades in existing mines, shortages of electrical energy (e.g. in Chile) and an aging workforce are the most significant among the megatrends affecting our industry. In addition to this, flat underlying commodity prices and high price volatility are currently posing strong requirements to miners when entering into the process of approving investments.Nowadays to get projects financially approved (optimizations, expansions, new plants), capital expenditure has to be reduced, as observed up to 30% compared to the last decade, and at the same time the plant design has to be such to demonstrate that operating costs will also be significantly lower than in the past.When it comes to the concentrator plant, the concept of large single line grinding circuits provides a valid answer in project feasibility studies by significantly reducing the capital investment requirements compared to parallel lines for the same plant throughput rates. The benefits of this concept are reflected as well on the operational costs, in terms of higher and greater process stability and reduced maintenance expenditures."

Jan 1, 2016

By David D. Eyer

Since the decade of the 1990s is nearly upon us, I have focused on what I see are the likely trends featured in new large underground coal mines 10 years from now. I do this from the vantage point of having been involved in the installation of large mines for more than twenty years. Little of the equipment resources we have available today was unknown when I entered the coal business in 1960. There were continuous miners, longwalls and diesel-powered equipment in Europe, monitoring systems, computers, heavy media separation systems, froth flotation and conveyors then as there are now. A substantial evolutionary process has occurred with these and other mining machines and processes. Some evolved only to die out, such as boring-type continuous miners; others, such as longwall systems, flourished. My intuition tells me that since there have been largely evolutionary rather than revolutionary developments in the near past, the same is true of the future, at least for the next 10 years. In other words, the elements of what are in the future are with US now. Some, such as computer-based applications, may evolve beyond our wildest dreams -but I doubt it.

Jan 1, 1988

By A. N. Pritchard

The development of vibrating screens over the last century has seen many variations to suit the exacting requirements of industry. Indeed, as each year passes, industry has presented the challenge to screen manufacturers of supplying larger machines than those used in the past and the question is often posed - what is the maximum limit? Not only must size or screen area be considered but excellence of performance in terms of screening efficiency must be maintained or maximized.

Jan 1, 1983

By Ian Orford, Ken L. Boyd

"Can the ever-increasing tonnages of ore and waste being mined today be accommodated simply by using bigger and better crushers? This paper updates the principal author’s earlier publication, “Crushing Plant Design and Layout Considerations” (SME Mineral Processing Plant Design, Practise, and Control, 2002). It reviews the latest primary crushing and large cone crusher designs. Its goal is to help consultants and operators select the optimal equipment and custom-designed items in the material handling flowsheet from the mine to the mill, maximizing operating hours per year.INTRODUCTIONAre larger crushers the answer to meeting the demands of existing or new mining projects for increased tonnage? The principal author’s previous paper in the year 2002 on ""Crushing Plant Design and Layout Considerations"" provided a detailed design and layout review for the design of primary and fine crushing (Secondary, Tertiary, Quaternary) mineral processing facilities. Some of the conclusions in this previous paper had predicted that larger crushers for primary and fine crushing would be beneficial and contribute to the further development of mineral processing. Larger crushers for primary and fine crushing applications are now available.The rock size reduction process, from the mine to the selected milling process facility has not changed since man first broke a rock to get at the interesting mineralization within. The rock size reduction process circuit from the mine to the mill can be summarized into four (4) stages:• Stage 1: Mining ( Rock Breakage and Fragmentation)• Stage 2: Pre-Screening (Scalping)• Stage 3: Primary Crushing• Stage 4: Fine Crushing (Secondary, Tertiary and Quaternary; the crushers used in this stage are identified by the titles which usage has conferred on them)Plant throughput and ore delivery schedule will form the basis for flowsheet design and equipment selection. Once a project's design criteria and the mine plan has been established, the actual circuit's utilization percentage (percentage of hours when the circuit is being utilized) can be optimized for each of the four stages. The mining and process departments are the key stake holders in the selection of the final comminution circuit and both departments should be familiar with and contribute to the design of the circuit."

Jan 1, 2016

By K. L. Boyd

"Can the increasing tonnages of ore and waste mined today be accommodated simply by using bigger and better crushers? This paper reviews the latest primary crushing and large cone crusher designs. It highlights how—in addition to using the larger crushers now available—maximizing the utilization percentages in each stage of the rock size reduction circuit will assist in meeting the larger production requirements of existing and new mining operations. Its goal is to help consultants and operators select the optimal equipment and custom-designed items in material handling from the mine to the mill, maximizing operating hours per year.RÉSUMÉ Le recours à des concasseurs plus grands et plus performants suffit-il à gérer l’augmentation du tonnage du minerai et des déchets que l’on extrait de nos jours ? Cet article examine les tous derniers modèles de concassage primaire et de grands concasseurs à cône. Il montre que, pour satisfaire aux exigences de production plus conséquente des exploitations minières existantes et nouvelles, il est important d’optimiser les taux d’utilisation à chacune des étapes du circuit de réduction de la taille des roches, en plus d’utiliser les concasseurs plus grands actuellement disponibles. L’objectif de cet article est d’aider les sociétés d’experts-conseils et les exploitants à sélectionner le meilleur équipement ainsi que des articles fabriqués sur mesure pour la manutention de la mine au concentrateur, en optimisant les heures d’exploitation par année.INTRODUCTIONAre larger crushers the answer to meeting the demands of existing or new mining projects for increased tonnage? Boyd (2002) predicted that larger crushers for primary and fine crushing would be beneficial and contribute to the further development of mineral processing. Larger crushers for primary and fine crushing applications have since become available.The rock size reduction process from the mine to the selected milling process facility has not changed since a person first broke a rock to get at the interesting mineralization within. The rock size reduction process circuit from the mine to the mill can be summarized in four stages:• stage 1: mining (rock breakage and fragmentation);• stage 2: prescreening (scalping);• stage 3: primary crushing; and• stage 4: fine crushing (secondary, tertiary, and quaternary).Plant throughput and ore delivery schedule will form the basis for flowsheet design and equipment selection. Once the project design criteria and the mine plan have been established, the circuit’s utilization percentage (percentage of hours when the circuit is being utilized) can be optimized for each of the four stages. The mining and process departments play a key role in the selection of the final comminution circuit, and both departments should be familiar with and contribute to the design of the circuit."

Jan 1, 2017

By K. L. Boyd

"Can the ever-increasing tonnages of ore and waste being mined today be accommodated simply by using bigger and better crushers? This paper reviews the latest primary crushing and large cone crusher designs. It highlights how—in addition to using the larger crushers now available—maximizing the utilization percentages in each of the four stages of the rock size reduction circuit will assist in meeting the larger production requirements of existing and new mining operations. Its goal is to help consultants and operators select the optimal equipment and custom-designed items in the material handling flowsheet from the mine to the mill, maximizing operating hours per year. INTRODUCTION Are larger crushers the answer to meeting the demands of existing or new mining projects for increased tonnage? Boyd (2002) predicted that larger crushers for primary and fine crushing would be beneficial and contribute to the further development of mineral processing. Larger crushers for primary and fine crushing applications are now available. The rock size reduction process from the mine to the selected milling process facility has not changed since man first broke a rock to get at the interesting mineralization within. The rock size reduction process circuit from the mine to the mill can be summarized in four stages: • Stage 1: Mining (rock breakage and fragmentation) • Stage 2: Pre-screening (scalping) • Stage 3: Primary crushing • Stage 4: Fine crushing (secondary, tertiary and quaternary) Plant throughput and ore delivery schedule will form the basis for flowsheet design and equipment selection. Once the project design criteria and the mine plan have been established, the circuit’s utilization percentage (percentage of hours when the circuit is being utilized) can be optimized for each of the four stages. The mining and process departments are the key stakeholders in the selection of the final comminution circuit, and both departments should be familiar with and contribute to the design of the circuit. This paper focuses on the four stages of a rock size reduction circuit from the mine to the mill, equipment selection, various ore and waste handling flowsheets, and improvements in crusher station design, all with the purpose of maximizing availability and plant utilization percentages. What is a large tonnage? From 1907 to 1914, the American Panama Canal excavated 300 million tonnes of material in 7 years (History of the Panama Canal, Wikipedia). Today’s large mining operations can move the same material in 10 months, using large crushers or multiple crushers for ore processing and large crushers and a mixture of truck haulage and conveyors for handling the large waste tonnages. Some examples include:"

Jan 1, 2017

By Andrea Zanon

Recently steel manufacturers have significantly focused their attention on safety and working conditions thanks to new labour laws, comprehensive operators’ knowledge and increased company social responsibility. Even with a reduced budget, investments on safety are now widely approved. Mill constructors aim at developing upgraded solutions to comply with these new requirements. In some cases mill constructors can even anticipate customers’ requests and consequently put into the market innovative solutions. In this text we will analyze some advanced solutions developed by Danieli & C. Officine Meccaniche Spa - the leading company in long-product rolling mills - aimed at improving working conditions on wire-rod block settings. In particular, we will focus on rolling guides installed on fast-finishing blocks and on servo-assisted device for rolling rings changing. In fact, this equipment has shown effective benefits on our test plants and has mainly cut out the tendency of the personnel to be absent due to backache. This paper will first present standard working conditions, will then introduce the newest equipment developed by Danieli & C. Officine Meccaniche Spa, will analyze its operation and finally will describe in detail the benefits that can be reached with its use.

Jul 30, 2018

By W Malone, J Garrett

FLSmidth (FLS) has spent the last 15 years, working with customers and engineering houses to deliver innovative improvements in crusher safety, coupled with the latest, maintenance friendly, crusher design. The key focus being to prevent service personnel from working underneath the crusher during maintenance and obviate the need for personnel to be exposed to suspended loads when performing tasks such as, main shaft installation, for example. Improvements include: full top-service capability to ensure the safest and fastest way to disassemble the crusher for maintenance purposes, which also removes the requirement for a service cart; a selfaligning main shaft which ensures remote assembly is now possible, keeping service personnel well out of harm’s way; And rotable shells, or the ability to perform relines off-station, allows for quick shell ‘swap-over’ without the downtime associated with removing, refitting and curing time associated with epoxy backing. The high flow spider improves large material entry into the crusher, reducing blockages and downtime and therefore maintains crusher capacity. Each size of crusher in the range comes with an option to increase the standard feed opening to a larger one if desired to compensate for ‘blocky’ or ‘elongated’ feed material, a common problem for Pilbara hematite iron ores. Power capability has also been increased with a maximum of 1500 kW, to match the higher throughput capacities being achieved. This due to uprated eccentric speeds and larger discharge annulus. Increased eccentric throws and mantle diameters are also now a reality, when compared to more traditional designed gyratory crushers. To keep up with the improved design features of the Mk V, digitalisation has also been upgraded to maximise performance capabilities to ensure that the most efficient reduction and throughput capacities are achieved, whilst utilising the higher powers now available as standard. Condition monitoring ensures that the crusher is at its optimum operating capability by monitoring and adjusting the crusher settings via feedback from additional sensors, ie main shaft spin, temperature and vibration. Camera monitoring capabilities are available as is an advanced oil contamination monitoring system. As a result of the above design improvements, it will be shown that the Mk V range offers benefits such as: enhanced safety features, increased availability, faster maintenance turnarounds, higher power utilisation, equivalent product size at higher throughput capacities and with Remote operation capabilities. All of which result in a gyratory crusher with higher levels of safety and a lower per tonne operating cost.

Sep 18, 2023

By Carsten Gerold

The paper is giving an overview about successful operating Loesche Vertical ? Roller ? Mills (VRM) installations and summarises the main benefits of the dry compressive Loesche grinding technologies in Airflow- and Overflow-Mode. Some of these benefits are optimised energy efficiency of the grinding - classifying - circuits, increased mineral recoveries and decreased OPEX costs, at a parallel simplification of the process route. Within this paper the process values of the Loesche VRM are compared to existing or planned conventional grinding ? classifying circuits. Further advantages discovered in pilot trials and examples for new more efficient process route alternatives are given. The paper reports about production and pilot trial experiences obtained by crushing and grinding Iron Ore, Iron Ore Concentrates, Copper Shale, Copper Matte, Copper Slag, Titanium Slag, Tin Slag, Steel and Stainless Steel Slag with Loesche VRM.

Sep 1, 2012

By Orlando Martino

This regional report covers the mineral industries of Canada and 40 countries and areas in Latin America and the Caribbean Basin. Also included is a brief description of the mineral potential of Antarctica. The Latin American region encompasses an area twice that of the United States. Latin America and Canada have a rich and diversified endowment of mineral fuels, metals, and industrial minerals. Tables 2 and 3 provide a summary view of the importance of Latin America and Canada's output of its major mineral commodities in world mineral supply in 1989 and 1990.

Jan 1, 1993

By Luis Fernandez-Deza, James Hawn, Dustin Mount, Jean-Marc Wehrli

The RiverRenew Tunnel System project in Alexandria, VA forms part of a CSO scheme aimed at reducing overflows of combined stormwater and sewage into the Potomac River during storm events. A major piece of the project is a 12-foot internal diameter tunnel of approximately 12,000 feet length lined with a single-pass precast concrete segmental liner and excavated by an Earth-Pressure Balanced Shield TBM. The tunnel lies between 120 to 140 feet below grade in the clays of the Upper Potomac Formation with occasional dips of more granular, saturated soils of the Terrace Formation and the Alluvium. The TBM is launched from a figure-8 configuration Pumping/Screening Shaft located within AlexRenew’s operational Water Resource Recovery Facility. This paper discusses the challenges encountered during the launch of the TBM in short mode within a highly congested site and from narrow deep shafts.

Jun 13, 2023

By Alessandra Spaghetti

Rolling small-diameter hot wire rods at high speeds with conventional laying head pipes can wear the pipe out frequently and affect quality and consistency in the final product. Laying head upgrades using Sandvik SAF2507LHP™ (UNS S32750) tubes make possible to achieve optimal metallurgical properties, smooth coil formation and easier coil handling. Operators can also avoid unwelcome shutdowns due to frequent worn pipe changes and turndowns. Sandvik have been developing different customers and understand their process needs. The suitable selection materials that are able to withstand high levels of wear better than low alloy and carbon steel grades that are commonly used in industry is very important to improve the quality and increase productivity. UNS S32750 tubes were demonstrably superior to low alloy and carbon steels when used in Laying Head Pipe system regarding tubes lifetime, reducing replacement, production interruptions and increasing reliability.

Aug 17, 2017

By Ning Wang, Tengfei Guo, Wanyan Li, Hanjie Wen, Hannian Gu, Zehai Li

Bauxite residue (red mud) is an alkaline waste derived from the industrial process for extraction of alumina from bauxite ore. Some bauxite residues contain considerable concentrations of critical metals, for example, rare earth elements. Lithium in red mud was also reported as a potential resource. In the current study, a Li-rich red mud was leached using acetic acid to investigate the leaching behavior of lithium followed by neutralizing with hydrochloric or oxalic acid. By neutralizing red mud using diluted hydrochloric acid (0.01 mol/L), 58.04–60.27% of lithium was leached using 25% acetic acid at 95 °C for 60 min. In the meantime, more than 95% of sodium and 85% of calcium were also dissolved in the leachate solution. While oxalic acid (0.5 mol/L) was used to neutralize red mud prior to acetic acid leaching, lithium performed lower leaching efficiencies (42.41–46.88%) in comparison of using of hydrochloric acid–neutralized red mud. Nevertheless, these leaching efficiencies of lithium were close to that of calcium and much higher than those of sodium under the condition. In this study, 25% (v/v) of acetic acid, at 85 °C for 60 min, was demonstrated as optimum conditions for lithium extraction from oxalic acid–neutralized red mud using acetic acid. The results would be useful and of interest for lithium recovery and purification from red mud.

By Kazutoshi Haga, Atsushi Shibayama, Altansukh Batnasan

The objectives of this study were to propose a viable alternative method for recovery of precious metals such as gold (Au), silver (Ag) and palladium (Pd) from waste printed circuit boards (WPCBs) and to regenerate the spent lixiviant solution for reuse. The proposed method generally consists of several steps as follows: 1). iodine-iodide leaching for metals extraction; 2). separation and recovery of precious metals and metal impurities from a pregnant leach solution; 3). regeneration of the spent iodine-iodide solution/lixiviant. In this method, more than 99% of Au leaching was achieved in the iodine-iodide solution from the solid residue of WPCBs that was obtained via sequential processes including incineration at 800 ?C and high pressure oxidative leaching with a diluted sulfuric acid at 120 ?C, while the leaching of Ag and Pd was less than 1%, respectively. Besides Ca, Cu, Ni, Co and Zn as main metal impurities, leaching efficiency of other metals did not exceed 1%. The precious metals and base metals as metal impurities present in the pregnant leach solution were separated and recovered by precipitation using L-AA and NaOH solutions. About 99.8% Au, 81.7% Ag and 72.8% Pd were recovered from the pregnant solution at pH of 2 with the addition of 0.1 M L-AA as precipitating agent. The remained small amounts of precious metals and metal impurities were precipitated at pH 13 using 1 M NaOH. The spent lixiviant after sequential precipitation was regenerated in the presence of hydrogen peroxide, hydrochloric acid and potassium iodide. It was revealed that over 90% of gold could be extracted from the residue of WPCBs with the regenerated lixiviant solution.

Jan 1, 2018