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By F. B. Henderson

1.0 PROLOG Since the "end" of the Cold War, revolutionary new research and commercial remote sensing capabilities are being developed that will dramatically change the way we map the earth and address its environmental problems. The technology challenge is not the growth of new environmental remote sensing technologies themselves. It is, rather, how these new innovative observing systems can be accepted and used to the benefit of both the regulatory and the mining communities in the light of present concerns about unknown risks of discovery and liability. The basis for this paper is an unpublished technology primer prepared for the industry-government Workshop on Advanced Measurement and Site Characterization for Mining Impacts held at Colorado School of Mines, Golden, Colorado, July 14-17, 1997

Jan 1, 1999

By F. B. Henderson III

Since the "end" of the Cold War, revolutionary new research and commercial remote sensing capabilities are being developed that will dramatically change the way we map the earth and address its environmental problems. The technology challenge is not the growth of new environmental remote sensing technologies themselves. It is, rather, how these new innovative observing systems can be accepted and used to the benefit of both the regulatory and the mining communities in the light of present concerns about unknown risks of discovery and liability. The basis for this paper is an unpublished technology primer prepared for the industry-government Workshop on Advanced Measurement and Site Characterization for Mining Impacts held at Colorado School of Mines, Golden, Colorado, July 14-17, 1997

Jan 1, 1999

By Dean H. Ambrose

[Mining and processing earth's materials form the basic building blocks from which many technology advancements and products are made. Virtually all metallic and non- metallic products are derived from a substance found in our earth that we blend, mold, extrude, or pulverize into something useful, the mining industry is responsible for the first step of this process: extraction from the ground. Mining particularly coal mining. poses significant risks to both humans and machines. As raw materials are]

Jan 1, 2009

By J Kelly, C Kelsey

The Autogenous Kelsey Axial Displacement (KAD) mill is essentially a short retention time centrifugal mill, designed to effectively harness extraordinarily high concentrations of input energy for efficient particle size reduction. The mill which has an operating duty band extending from primary to ultra-fine also has the unique capacity to generate fine and ultra-fine products from single stage size reductions of either coarse or fine mineral feeds, in both wet or dry operating modes. This paper covers developments following a recent optimisation programme which confirmed that mill shell speed and the velocity differential between the shell and the rotating internal disc assembly tips could be optimised in relation to specific energy for a given feed rate and feed size providing the product size remains constant. Subsequent test-work further demonstrated the versatility of the mill with duties ranging from the removal of surface contamination associated with heavy mineral concentrate particles to the production of premium ultra-fine talc, from a single stage of size reduction. Open circuit grinding of a rougher gravity concentrate to liberate gold ahead of leaching also highlighted the scope for the application of low cost KAD milling for a range of hydrometallurgical feed preparation duties, which involve fine and ultra-fine grinding.CITATION:Kelly, J and Kelsey, C, 2013. Advanced media-free fine and ultra-fine grinding - The Kelsey axial displacement mill, in Proceedings MetPlant 2013 , pp 152-161 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By E. H. Myrhaug, K. Aasly, T. Malvik

Six different types of quartz and quartzites used as raw materials by ferroalloy plants have been investigated with respect to their thermo mechanical properties. In order to investigate the effect of the thermal shock caused by the rapid heating of quartz when it enters the furnace, the following techniques have been used for both in situ investigations and investigations of pre-heated quartz: -Heating stage microscopy for in situ observation of heating effects. -Shock heating of quartz in an induction furnace An optical microscope-mounted heating stage was used for in situ observations of the microscopic effects of heating up to 1300 ºC. The effects of heating were observed at different temperature intervals in different samples. The main temperature intervals were below 573 ºC and above 1000 ºC. The cause of the observed effects is interpreted as fluid inclusion decrepitation for T<573 °C and structural implications (micro cracks, grain boundaries and remaining fluid inclusions) at T>1200 °C. Shock heating of the samples was carried out in an induction furnace to 1300 ºC for ten minutes. The effects of the heating were studied with different techniques such as direct observation during and directly after heating, optical microscopy and XRD. Combined transmitted and fluorescence light microscopy shows that the heated quartz show an opening of the grain boundaries and evenly distributed micro cracks that were not present in the unheated reference samples. In some of the heated samples, weak generation of cristobalite was detected by XRD.

Jan 1, 2007

RME has a vision for a new grinding plant operational paradigm made possible by RMEÆs fast, safe Mill Relining System. Some new liner designs can degrade SAG mill performance because of mill volume loss, ball strike (rotational speed limitations) and other issues often brought about by modifying liner design for maximum life and without a backward glance at metallurgical consequences. Freshly relined mills can initially produce as little as 80 per cent of their maximum throughput, that maximum occurring toward the end of the linersÆ wear life. RMEÆs proposition is to see new liners designed for maximum commercial performance. This may mean more frequent mill relines but with liners designed to yield optimum grinding, metallurgical and profitability performance, not maximum life. In other words, mill liner profiles and mill relining speed become key operational controls and not simply æmust doÆ maintenance functions. Taken to the extreme, liner profiles may prove capable of ætuningÆ a grinding plant for maximum profitability in any metal price environment. Following the introduction, the first section of this paper provides an update describing recent and significant developments within RMEÆs range of Mill Relining Systems, the enabling technologies which permit more frequent liner exchange without incurring additional downtime imposts. The second section outlines RMEÆs vision of a æliner profile versus profitabilityÆ commercial model, developed either intuitively or by using a combination of new measurement and modelling technologies. These new measurement and modelling tools provide the opportunity to predict the optimum commercial outcome, off-line in the virtual world, before committing to an expensive liner experiment.

Jan 1, 2007

RME has a vision for a new grinding plant operational paradigm made possible by RME&apos;s fast, safe Mill Relining System. Some new liner designs can degrade SAG mill performance because of mill volume loss, ball strike (rotational speed limitations) and other issues often brought about by modifying liner design for maximum life and without a backward glance at metallurgical consequences. Freshly relined mills can initially produce as little as 80 per cent of their maximum throughput, that maximum occurring toward the end of the liners&apos; wear life. RME&apos;s proposition is to see new liners designed for maximum commercial performance. This may mean more frequent mill relines but with liners designed to yield optimum grinding, metallurgical and profitability performance, not maximum life. In other words, mill liner profiles and mill relining speed become key operational controls and not simply `must do&apos; maintenance functions. Taken to the extreme, liner profiles may prove capable of `tuning&apos; a grinding plant for maximum profitability in any metal price environment. Following the introduction, the first section of this paper provides an update describing recent and significant developments within RME&apos;s range of Mill Relining Systems, the enabling technologies which permit more frequent liner exchange without incurring additional downtime imposts. The second section outlines RME&apos;s vision of a `liner profile versus profitability&apos; commercial model, developed either intuitively or by using a combination of new measurement and modelling technologies. These new measurement and modelling tools provide the opportunity to predict the optimum commercial outcome, off-line in the virtual world, before committing to an expensive liner experiment.

Jan 1, 2007

By J Young, S Yu, P Moyo, M Powell, A Musunuri, B Bonfils, S Kanchibotla, P Yaroshak, V Jokovic

The appropriate design of liners continues to be an issue on many mills worldwide. Loss of milling capacity especially at liner change, uneven wear lives along the mill, substantial scrap on worn liners, excess mill down-time, undesirably short and unreliable wear lives are all common issues. This paper presents a designed approach to liner optimisation that follows a logical path of initial design and step-wise improvements based on liner wear monitoring. The target is to have a good liner design from start-up, then tune the profiles, heights and thicknesses based on wear monitoring. This is conducted as a team of liner specialist, site personnel and liner supplier. The application to the Pustynnoye SAG mill of JSC Altynalmas in Kazakhstan is presented. The increase in liner life by around 50% along with increased mill throughput of over 20% illustrate the huge benefit of the cooperative triumvirate approach through the gains that can be made in productivity and reduced liner costs.CITATION:Powell, M, Kanchibotla, S, Jokovic, V, Hilden, M, Bonfils, B, Musunuri, A, Moyo, P, Yu, S, Young, J, Yaroshak, P, Yalcin, E and Gorain, B, 2018. Advanced mine to mill application at the Barrick Cortez mine, in Proceedings 14th AusIMM Mill Operators&#39; Conference 2018, pp 177–196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By M. Giralico

Optimized mixer settler designs will now handle flows of over 25,000 GPM. The size and expense of the equipment hamper experimental settler optimization efforts. Computational Fluid Dynamics (CFD) is a timely and predictable tool for settler design development. In the past, CFD has been used to evaluate only the flow field in pumped and auxiliary tanks. A similar numerical analysis is used to evaluate settler flow and phase separation. Phase separation is analyzed using multiple species for the aqueous and organic phase. Experimental validation shows good agreement between the computational and experimental solutions in both flow field and phase separation. The computational model is used to show performance differences between various choices of settler geometry, liquid depth, with variable flow rates. Understanding the differences allows the development of optimized settler designs. System improvements are predicted to lower entrainment levels further and/or allow new smaller footprint designs. This paper focuses on the major design components of the settler and how future technological advances will lead to further improvements in their design. LIGHTNIN?s new designs will handle tomorrow?s production requirements, while maximizing profits.

Jan 1, 2003

By John A. Herbst

Professor A.M. Gaudin and his students at MIT were dedicated to understanding the fundamentals of mineral processing and as a consequence were constantly searching for better quantatative descriptions of size reduction, liberation and mineral separations. I have had the good fortune of meeting Professor Gaudin and working with many the modeling pioneers who followed him. I have observed first hand the refinement of mineral processing models as they increased in realisticness moving up the steps of the pyramid (see figure below) from pure empiricism to the current pinacle of physics based models. During this journey our industry benefited significanbtly as model prediction errors were reduced from ± 20% to ± 1%. Unit operation and plant simulations improved in accuracy and speed of calculations.

Sep 1, 2012

By K. Harris, J. B. Wahl

Ni-base superalloy cast materials provide an outstanding balance of high temperature strength, fatigue resistance, oxidation resistance and coating performance and can be produced to very tight tolerances in extremely complex configurations, such as axial and centrifugal integral cast turbine wheels. As a result, cast superalloys are used in the most demanding applications of aero and industrial gas turbine engines. Use of these materials is expanding to smaller microturbine, turbojet, turbocharger and missile engine applications due to this unique combination of desirable properties. This paper will present an overview of the application of investment cast Ni-base superalloys and process capability to small turbine and missile engines.

Jan 1, 2010

By J. S. Becker

Technology developed and first implemented in the United Kingdom enables very low grade aluminum scraps containing oils, organics, plastics and ferrous metals to be directly charged, without pretreatment, into a unique melting furnace. The system has been in full scale production for four years. The oxy-fuel-based furnace design incorporates internal afterburning in the furnace&apos;s hot zone, producing excellent thermal efficiency and very low emissions. The furnace is inherently low in NOx. This paper will provide both theoretical background and extensive operating results for this new melting concept. Applications describing both purpose built new furnaces and retrofits of existing reverberatory furnaces will be presented. Extensive operating emissions data will be presented.

Jan 1, 1997

By Peter Sylvén, Darwin Morales

Despite being crucial for the smelting process, furnace tapping using oxygen lances has not been considered an operation that brings value. Therefore, these important tools have not seen a significant change in over 100 years. Problems related to the use of oxygen lances include: • Inaccurate tool: causing damages shortening the life of the taphole refractories. • Safety: extended exposure to the operator in an unsafe area of the furnace. • Cost: high oxygen consumption & high lance consumption. • Time consuming and frustrating to connect one lance to another. This paper will suggest a very good solution; new concept thermal lances. We will show how these provide an outstanding performance for a more efficient, faster and cost-effective furnace tapping operation. These new lances are very accurate tools that enable the operator to perform a more controlled operation; resulting in longer taphole life, fewer repairs and less down-time.

Jan 1, 2016

By Robert W. Row

Advanced physical coal cleaning processes that are now under development may remove significantly greater fractions of pyritic sulfur and ash than do commercial coal cleaning processes at comparable heating value recoveries. These processes may be useful for reducing sulfur dioxide emissions from electric utilities and other emission sources. However, little work has been done to determine their applicability to any major coal market. The northeastern states of the United States are interested in burning more coal, but with further sulfur dioxide emission restrictions. Their nearest coal sources are relatively high sulfur Northern Appalachian coals. The project discussed in this paper, which is scheduled to be completed in June 1985, has the objective of technically and economically evaluating various coal supply scenarios involving five selected advanced physical coal cleaning processes; and comparing the economics of them with alternative fuel supply options open to the northeastern users.

Jan 1, 1985

By Kevin Vander Tuig, Tim O’Rourke, Rick Vincent, Doug Lopata, Kellie Rotunno, Dan Dobbels

"The Northeast Ohio Regional Sewer District (NEORSD) was required under the Federal Clean Water Act and U.S. Environmental Protection Agency’s (U.S. EPA) Combined Sewer Overflow (CSO) Control Policy to develop a Long Term Control Plan (LTCP) to reduce or eliminate overflows from its permitted CSO outfalls. The LTCP was completed in 2002. Key components of the plan include: 26 miles (42 km) of deep storage and conveyance tunnels providing a total CSO storage volume of 325 million gallons (MG) (1.2 billion liters); over 30 miles (48 km) of consolidation sewers to route CSO control flows to the tunnels; and associated diversion/inflow control structures and drop shafts. Final design and construction of the initial phases of the LTCP are completed or underway. Advanced planning of the final phases began in April 2013. This paper summarizes this advanced planning process and, specifically, how hydraulic performance and tunnel design and construction considerations were balanced to eliminate unnecessary projects and shafts, reduce implementation risks, and reduce program costs by approximately $650 million. BACKGROUND The Northeast Ohio Regional Sewer District (District) serves an area of approximately 350 square miles (SM) (907 km2), including combined (81 SM; [210 km2]) and separate (269 SM [697 km2]) sewer systems that discharge to three wastewater treatment plants in the greater Cleveland area. The service area, shown in Figure 1, is divided into three districts—Easterly, Westerly, and Southerly—each having its own interceptor system and treatment plant, ranging in wet weather treatment capacities from 100 to 735 million gallons per day (MGD) (378.5 million to 2.8 billion L/day). The system includes 124 permitted combined sewer overflow (CSO) outfalls overflowing into the region’s tributary streams, Cuyahoga River, and Lake Erie."

Jan 1, 2016

By Andreas Hucke

For the roadway design in the German hard coal mining industry, an advanced combined planning system has been applied during the past 20 years. The German mining industry is working with single entry roadways system. After first longwall passage the roadways will be stabilised with side wall building material packages. Later this roadway will be used again for the second retreating longwall. The intention of the implementation of several different design methods for the planning of the roadways is to enhance the reliability of the results. On one hand the planning system uses numerical simulation and physical modelling in addition to analytical and empirical methods. On the other hand in-situ monitoring and analysis during the roadway development will be used to verify and calibrate the numerical and physical models. Especially before the implementation of new support elements in underground, this system is suitable and reasonable because the new support elements will be tested in the physical and numerical simulation prior to cost intensive underground tests. The interaction between the numerical and physical modelling in comparison with underground monitoring and analysis during development and the later use of roadways will be shown with some examples. The first example shows a rock bolted rectangular roadway which will be mined at both sides of the roadway. Different support and roadway building material package systems are investigated under various stress conditions. The results are utilised to optimise the roadway support and the roadway side package systems. The influence of different points in time of the installation of several support elements in a combined arch and bolted roadway is shown as another example. Two different types of support systems are compared within the physical models. These models are used as a base for ongoing numerical analysis and simulation to find out the ideal point of time to assemble the different support elements. The last example handles the influence of slickensides in the roof of arch shaped roadway on their stability. Different slickenside positions and densities are investigated and classified.

Jan 1, 2006

By T. Bohmer, L. Auret, N. Pillay, Z. Horn, P. Rambalee, A. Haasbroek

As part of a broader digital technology-enabled transformation programme, a major mining company is systematically implementing Advanced Process Control (APC) solutions and associated instrumentation throughout their operations. This paper highlights the approach and benefits of this holistic approach for a specific instrumentation installation, and APC installation at a South African coal processing plant. For the coal processing plant under consideration, a systematic approach was followed. Process sections/units are considered from upstream to downstream processing. APC solutions are designed for each process section and each process section is interrogated in terms of availability of sufficient process measurements to ensure stable, capable, and ultimately, optimised performance. Where insufficient process measurements are available, instrumentation upgrades are implemented. Finally, APC solutions are implemented, and evaluated in terms of productivity, safety, health, and environmental benefits. For the flotation section, an opportunity was identified to install froth sensors. The installed froth sensors provide measurements on froth velocity, bubble size, height, colour, and stability. The improved visibility that the froth sensors provided on the flotation process resulted in quick gains in terms of productivity: for example, instability in the feed to the flotation section could be quantified. This resulted in targeted process troubleshooting in an upstream thickener, and subsequent improvement of process stability, and reduced feed variance. The measurements from the froth sensors were further integrated in an APC solution. Proportional mass pull contributions per cell and per line can be inferred from the froth sensors, serving as controlled variables, while pulp level set points serve as the manipulated variables. On-off tests indicated that the advanced process control solution provided increases in yield and product quality.

Sep 1, 2021

By D. Groenveld, M. Rozou

"Recent trends move towards automation, smart sensors, internet of things, powerful DCS, and more data. Are those trends already utilized in a real time production environment? Today operators still have to monitor several complex processes at the same time and predict their behavior based on an overwhelming amount of data available.The fact of the operator being overloaded and humans being unable to process multivariable problems shows the need of a tool merging essential data and providing consistent, sound decisions for long-term profitability.This paper shows a successful execution of ABB’s process improvement services in Aitik (Boliden SA), a copper mine located in Sweden. Soft sensors, fuzzy rule blocks and model predictive control were seamlessly integrated in the control system of the grinding area, resulting in proper control of mill loads and particle size without violation of any constraints.INTRODUCTIONDepending on the ore characteristics and the targeted plant capacity, the design of the grinding circuit may vary significantly. Typically, the circuit consists of several mills (rod, ball, SAG, AG) in series and/or parallel with a number of classifiers and sumps at appropriate locations. The goal of the grinding section is to reduce the ore particle size to a level that enables efficient separation between gangue and precious metals in the subsiding processing step. The trade-off between quality and quantity has to be made. It is also crucial to execute this process step at the lowest possible energy and grinding media consumption.An optimal grinding process controller must manage to maintain a given fresh feed level while keeping the product size within a given range without violating any constraints such as power, torque or load limits. To accomplish the aforementioned, it is necessary to manipulate the ore feed rate, water feed rate and the mill speed. The most significant disturbances adding another degree of complexity to this control problem are ore hardness and the amount of circulating load."

Jan 1, 2016

By E. Gallestey, D. Groenveld, F. Kolb, M. Rozou

"Recent copper price evolution pushes modern mining industry even harder to achieve highest production with maximum efficiency. Operations are bound by numerous contractual and environmental conditions that bring a high degree of complexity to both the operators controlling the process and the plant managers assessing the circuit’s potential and setting the production goals.Advanced process control (APC) for grinding is one important tool to operate this most energy intense area in an optimal way, finding the optimal trade-offs between highest throughput, energy efficiency and product quality based on variable ore properties, production targets and management priorities.ABB’s state of the art control and optimization software platform enables user to design a controller based on model predictive control (MPC). The paper and the presentation show the technology used and the results achieved through an APC controller installed in a pilot project in Aitik (Boliden SA), Sweden. Furthermore, possibilities to interconnect grinding with other areas as stockpile management and flotation with various interconnected APC controllers will be shown. Finally, an example of the return on investment and the payback times based on the increased throughput and better product quality will be presented.INTRODUCTIONDepending on the ore characteristics and the targeted plant capacity, the design of the grinding circuit may vary significantly. Typically, the circuit consists of several mills (rod, ball, SAG, AG) in series and/or parallel with a number of classifiers and sumps at appropriate locations (see Figure 1).The main goal of the grinding section is to reduce the ore particle size to a level that enables efficient separation between gangue and precious metals in the subsiding processing step. The trade-off between quality and quantity has to be made. At the same time, it is also crucial to execute this process at the lowest possible energy and grinding media consumption."

Jan 1, 2015

By M. V. S. Cavalcante

The quality of iron ore pellets, represented in terms of parameters such as cold compressive strength (CCS) and Tumble Index (TI), has a strongly influence on the productivity and energy of reduction furnaces like the blast furnace and on the quality of hot metal or liquid iron. The main objective of pelletization operations is to produce iron ore pellets of desirable specifications and ensure high levels of plant productivity and energy efficiency. Advanced process control of an industrial iron ore pellet induration process using a soft sensor for pellet quality and fuzzy-logic based control algorithm is described in this paper. The pellet quality soft sensor consists of a rigorous mathematical model of the induration process and a statistical model for the pellet quality parameters. The mathematical model is based on the fundamental principles of heat and mass transfer between gases and pellets, kinetics of drying and condensation of moisture, combustion of coke, calcination of limestone, and melting and solidification of pellets. The predictions of wind-box temperature profiles are in close agreement with the measured profiles. The time-temperature profiles of the pellets during induration, along with raw material characteristics and induration process operating conditions, are used as inputs to the quality model to predict cold compressive strength and the Tumble Index. The predictions of the quality soft sensor along with the rules based on fuzzy-logic derived from simulation results and operator experience are then utilized to control the induration process to achieve precise control of the quality parameters and to optimize the induration process in terms of fuel efficiency and productivity. The mathematical model is also utilized as a soft sensor for temperature, moisture and composition profiles of pellets and gases. Results of implementation of this model-based control strategy on an industrial scale induration process will be presented. Keywords: iron ore, pelletization, simulation, process control, optimisation

Sep 1, 2012