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By W. Mueller

The function of a process mineralogist in the operation of a copper mine and plant is to assist in the identification and classification of the operation's main throughput. These include ore, concentrates, slag and matte, and to a lesser extent, refined products. In addition, a number of other products not normally thought of in association with mineralogy are examined. These include scales from submersible pumps, failed boiler tubes, acid plant, and shaft furnace; characterization of inclusions in failed compressor gear teeth as well as in copper rod; and flue dusts from a smelter, air transported particulates and coatings on passive copper anodes in the refinery. Techniques and equipment required for these studies include simple hand magnets to the high intensity Isodynamic separator, visual examination to electron microscopes, x-ray equipment, DTA, IR, heavy liquid separation, and contracted services of custom laboratories. Several examined products from Magma Copper Company have been selected to illustrate the range of techniques and equipment required by a process mineralogist.

Jan 1, 1981

By David Pierce

The Port of Seattle, one of the largest on the west coast of North America, made a strong statement regarding their support for reusing existing structures when a decision was made to rehabilitate Pier 69, on Seattle's downtown waterfront, for their new headquarters. Because of its age and location, the pier provided an unusual challenge to the Port and its consultants. The Port hired Peratrovich, Nottingham, and Drage Inc. to design the seismic strengthening of the pier itself. To remedy the lack of seismic resistance in the 70-year-old pier, PN&D designed a new steel-pipe-pile supported concrete apron next to it. The structure relied on a development by PN&D, the "spin-fin pile", to achieve the tension capacities required of the batter piles. The construction of this apron was completed in October of 1991. Another team of consultants performed the superstructure renovation design, which is now under construction.

Jan 1, 1992

By R. G. Church

Belle Ayr Mine was established in 1972 as the first large surface coal mine in the Powder River Basin of Wyoming. During the mid-1980s, it was eventually out-distanced in productivity by newer mines, and management recognized that the mine must recapitalize its major mining equipment and enhance its workforce flexibility in order to be competitive in the deteriorating market situation. Therefore, state-of-the-art haulage and loading equipment was placed into service, and a 12-hour rotating shift and a technician-based workforce was implemented. Belle Ayr Mine is located 29 km (18 miles) southeast of Gillette, Wyoming, in Campbell County (Figure 1). The mine is a part of AMAX Coal West, Inc., and with its sister mine, Eagle Butte, located 8 km (5 miles) north of Gillette, is a major contributor to the overall coal production of AMAX Coal Industries, Inc., headquartered in Houston, Texas. This paper addresses mine planning, recapitalization initiatives, and innovative workforce changes which propelled this large, surface coal mine to the forefront of productivity in the ever tightening low sulphur coal market.

Jan 1, 1994

By Christopher A. Jacobs

Project managers aim to maximise the NPV of their projects, but don't always appreciate the relationship between mine throughput, project value and the discount rate being used to evaluate their projects. Rate of production or throughput is perhaps one of the most crucial decisions a project manager must make, but if this choice is made arbitrarily, much effort may be spent on a feasibility study that does not optimise project value. The timing of the study in relation to the stage of exploration is examined and simple techniques are presented that project engineers and managers can use to home in on a production rate which will give their project the greatest chance of success.

May 1, 2006

By J Player, G Sweby

The material properties and hence performance of saturated alluvial sediments slope can be incorrectly forecast if the water content is not preserved, and materials properties not correctly determined. The occurrence of saturated sediments in the Western Australia (WA) Goldfields, while not common, should be a significant investigation focus. Geotechnical engineers new to the area may be unaware of this and hence the importance of correct testing and determination of the material strength. Application of appropriate analysis to determine stable pit slopes to an acceptable level of risk, is not possible unless the appropriate strength and hydrogeological parameters have been established at the outset. A back analysis is presented of a pit that had extensive slope failures in alluvial clay-rich sediments with discussion on the approach adopted by the original design engineers to assess pit wall stability and consequent poor slope performance. Learnings from a full pit 3D back analysis are presented, with an approach to geotechnical and hydrogeological investigations and analysis for slopes in similar materials.

Jun 22, 2022

By A Coelho, D Bruce, H Grosser, C Parken, M Xia

Carrapateena is a new underground sublevel cave mine and was officially opened in 2020. It has a mine life of 20 years. Development began in 2016, and with the rare opportunity to start a with a blank canvas and having a long mine life, an effort was made to explore how to incorporate innovative and leading-edge technologies. The Ventilation on Demand (VoD) system was designed with the objective to optimise power consumption and ventilation delivery through the primary and secondary ventilation systems. Primary fans controlled by Variable Speed Drives (VSDs) and dualwinding secondary fans with multiple setpoints control the delivery of overall quantity. Automated butterfly dampeners control the regulation of air to individual production crosscuts, and automated louvres control the exhaust quantities from the mining levels. Ultra-sonic flow sensors are installed to measure air quantity and environmental stations are installed to measure air quality. Both are designed to play a key role in control and calibration of the system. It was quickly identified that no one vendor could provide a holistic solution to meet the design requirements. A strategy was derived to use multiple vendors, harnessing the specific strengths of each. A control system has been developed to allow the Site Operations Control Centre (SOCC) to oversee and control real-time delivery of ventilation as required by operations. The first full level installation of the VoD system was completed in September 2020.

Mar 15, 2021

By Ahmed Alghamdi, Salem AlGharbi, Aisha AlHarbi, Owain Morton, Norah AlMuhaisen

This paper addresses the challenges in optimizing the phosphate flotation process, specifically focusing on the variability in P2O5 recovery. An artificial intelligence (AI) driven Flotation Prediction Model was developed to accurately forecast P2O5 grades. Leveraging real-time data from various operational sources, the model provides insights into how operators can opstimize key flotation parameters to enhance product quality and recovery rates. The results demonstrate the effectiveness of AI predictive modeling in addressing operational variability, marking a crucial step toward intelligent operations in the phosphate flotation process.

Feb 1, 2025

By Jason Clarke, Glen Trainor

As the mining industry faces increased challenges with declining ore grades and harder to access deposits, operating mine sites in an environmentally responsible and economically viable manner will require innovations that improve efficiency in energy logistics, and automation. Technological advancements in mining have been successful primarily because of the willingness and capability of these solutions to share information with one another, for example OEM payload systems sending information to Fleet Management Systems, and in turn Fleet Management Systems interfacing to ERP systems. To promote and facilitate the sharing of data, there has been a push towards open standards with initiatives led by organizations like ISO, ISA, EMESRT, and GMG. These efforts are aimed at creating a more collaborative and interoperable environment within the sector. However, when it comes to implementing autonomous solutions, a different trend dominates— closed-stack solutions. These closed stack solutions not only prohibit a mine site from selecting best-of-breed solutions, by blocking the competition from entering the market, they also risk slowing innovation that could help overcome the challenges the mining industry faces. Open Autonomy, an internationally published standard that allows any FMS to work with any Autonomous solution, breaks this closed-stack approach and invites competition from other industries. This competition comprises of autonomous suppliers from other industries and manufacturers of smaller, civil-sized haul trucks. The availability and capabilities of these smaller-sized autonomous haul trucks will help tackle the challenges of responsibly and economically mining lower quality ore grades and mining harder to access deposits.

Feb 1, 2024

By Ali Hafiz, Rich McCafferty, Chris Blanchard, Kaz Tabrizi, Kevin Ruston, Joseph Rigney, Mike Keville, James Dorta

Many existing tunnels have deteriorated as they age, requiring a massive amount of investment for their rehabilitation. The tunnel of interest in this paper is being rehabilitated by adding precast concrete arch panels under the existing concrete ceiling, and measuring the gap between them was the objective of this research. For this purpose, a mobile 3D laser/thermal scanner was used for scanning the tunnel, especially for the purpose of measuring its profile. To calculate the gap, the distance between the tunnel profile and the theoretical profile of the concrete arches was measured. Additionally, an in-house program was developed using MATLAB to automate the data processing to determine the above-referenced gaps. Results were provided in the form of heat maps showing the measured gap.

Jun 23, 2024

By Jamal Rostami, Tom Iseley, Saleh Behbahani

Tunnels and underground infrastructures assets, like all assets, deteriorate with time. At some point, they reach the end of their useful life. Therefore, frequent inspections, higher levels of maintenance, and rehabilitation are needed to address loss of life and safety concerns. The repair cost of tunnels will increase if maintenance of tunnels is not satisfactory and timely. Historically, tunnel inspections have primarily relied on visual and manual procedures. Due to their time-consuming nature and susceptibility to human error, there is a demand for alternative automated techniques that can enhance efficiency and reliability in tunnel inspection. By utilizing a tunnel scanning system, such as laser scanner and thermography, or photogrammetry system, tunnel inspection cost, time, and personnel can be reduced. The goal of this study is to utilize deep convolutional neural networks (CNNs) for automated identification of defects in tunnel lining inspection. This paper presents a framework to classify two types of defects in tunnel lining (water leakages and cracks) using CNNs. The CNNs were trained and tested using 4,608 images. The Precision, Recall, and F1 Score were each 99.6%, confirming the viability of this approach in the automated defect identification in tunnel lining.

Jun 23, 2024

By Dominic Ammon, Mark Rothbauer, Paul Landers P. E.

Across the Potomac River from the location of the DFI47 Annual Conference (October 2022), in Alexandria, VA, two large permanent anchored walls with a decorative shotcrete face were recently constructed for the North Hill project, a new multi-family and townhome development. The project was executed with a design-build approach for the Fairfax County Redevelopment and Housing Authority with review by the Fairfax County Geotechnical Review Board. The project was constructed in highly variable Potomac group sediments that include high plasticity clay/silt terrace deposits overlying coarser grained materials. The soils were over consolidated and exhibited potential for slickensides from relief of horizontal stresses from past erosion. The wall system was designed to include deep soldier piles and permanent long strand anchors considering past slope instability in the area. As the construction progressed, problematic soil conditions and water issues required modifications to drilling methods. The two permanent walls spanned 800 and 1,000 feet long with a maximum height reaching 40 feet.

Oct 1, 2022

By Arunsiva R., Sivaranan S., Venugopal B., Kumaran M.

Being a rapidly developing country, India is undergoing a massive infrastructure phase change remarkably. The construction industry is already set to boom, but the time and space constraints necessitate the employment of heavy plants and machinery to take the foundations deeper than ever. Operating such machinery on soft or poor ground conditions without a good working platform leads to uncertainties with massive loss of men and machinery. Plenty of such cases can be observed on construction sites across the globe. Unfortunately, forming a temporary working platform is given least to no importance in the construction industry, particularly ground engineering. This glitch can only be addressed through standard guidelines or codal recommendations on designing and implementing temporary working platforms issued by regulatory bodies. The present paper highlights the importance of providing the working platform, existing design method for working platforms such as TWf 2019:02 of Temporary Works forum, Building Research Establishment BR470 and a brief discussion on the design and construction of the geosynthetic reinforced working platform with a case study is also included. A pitch has been made on the importance of Indian codes/guidelines for the design and construction of temporary working platforms. These guidelines will ensure the safety of the men and heavy machinery and, in addition, increase the productivity of foundation construction irrespective of weather conditions and also become part of the regular construction scope.

Sep 1, 2022

By Garfiansyah Rayes

In 2023, an Indonesian coal mine experienced significant contamination of an emulsion blend explosive by dynamic mud and water flow, triggered by flooding due to exceptionally high rainfall. This intrusion into explosive columns compromised the stability and efficiency of blasting operations, thereby impacting overall mining productivity. The extent and impact of these contaminants on the stability and performance of the emulsion blend explosive were rigorously analyzed through a robust assessment methodology that included comprehensive field measurements and controlled laboratory experiments designed to replicate the challenging site conditions. Utilizing a combination of theoretical calculations and Computational Fluid Dynamics (CFD) simulations, this study evaluates the kinetic interactions between dynamic mud flows and emulsion explosives within drill holes. The methodology integrates Torricelli’s theorem for velocity assessments and Darcy’s Law for understanding the penetration mechanics of mud into the emulsion blend. CFD simulations are further correlated with actual blast data to assess discrepancies between theoretical predictions and real-world outcomes. Results demonstrate a significant reduction in the velocity of detonation (VOD) of the explo-sives, traced directly to mud contamination levels, which align with the quantified penetration rates in the study. Practical measures for mitigating such contamination are proposed, including the reinforcement of water-ways, culverts, and bund walls at drilling locations based on validated simulation data. Additionally, rec-ommendations for operational adjustments during high rainfall events are discussed, aiming to enhance blasting safety and efficiency. The paper concludes by suggesting future research directions towards the development of more resilient emulsion formulations and enhanced predictive modeling techniques to better forecast the impacts of en-vironmental variables on explosive performance in mining operations

Jan 21, 2025

By C. J. Pritchard, R. D. Jacksha, K. V. Raj, C. B. Sunderman

In underground metal/nonmetal mines, repeated localized short-term exposure to high levels of airborne contaminants can become a serious health issue. Currently, there are no common mechanisms to control or mitigate these short-term high exposures to contaminants. To improve miners’ health and safety, the U.S. National Institute for Occupational Safety and Health’s Spokane Mining Research Division (SMRD) is developing a smart monitoring and control (SMAC) system for the real-time monitoring of mine air quality, with integrated countermeasures to reduce high concentrations of airborne contaminants in localized sections of mines. To develop and test a SMAC system capable of being implemented in an underground mine, SMRD researchers built a test apparatus incorporating a fan, louver, ducting and sensors combined with atmospheric monitoring and control software. This system will institute effective countermeasures to reduce contaminant levels, improving miner safety and health.

Jan 1, 2018

By Chris Groccia, Damodara R. Chinnasane

Vale is in the process of resuming mining in the lower 810 ore body (810 OB) below 4130L at Copper Cliff Mine – South Side. Production in the lower 810 OB had continued until it was temporarily ceased in 2017 to allow for the execution of activities associated with Copper Cliff Mine Phase 1 project. While mining the stopes in both the lower and mid part of the 810 OB, a seismic response was experienced that resulted in rockbursts and challenging mining conditions. The majority of the rockbursts experienced in the past were associated with stopes mined in a bottom-up mining sequence under a diminishing pillar situation between 3350L and 3540L. The current mining plan is comprised of both top-down and bottom-up mining fronts using a center-out chevron sequence of long hole open stopes to manage induced stresses. Numerical modeling assessments have been carried out to forecast the response of the rock mass due to the planned mining. Seismicity and stress induced damage surrounding excavations are anticipated, and areas requiring extra attention have been identified. A tactical approach is being used to prepare the area for production, including replacement of ground support elements that are damaged or have insufficient residual capacity, and installation of dynamic support in areas anticipated to experience bulking and/or dynamic loading that would exceed the current support system’s capacity. A series of monitoring programs are being put in place to confirm current conditions, and to monitor the response of the rock mass to proactively implement ground control tactics should the need arise. This paper provides a summary of the approach used to forecast, monitor, and manage the behavior of the 810 OB rock mass response to continued mining at depth.

Apr 26, 2022

By Morgan L. Race, Matthew R. Glisson

"Most driven pile projects have plumbness limits from 0.25 in/ft (21 mm/m) to 0.5 in/ft (42 mm/m) to control bending stresses. For two projects, the project teams performed static load testing to evaluate performance of piles with sweep. One project, located in Grand Forks, North Dakota, used 9.625-inch (244-mm) diameter piles with a wall thickness of 0.395 inch (10 mm) and lengths ranging from about 130 to 160 feet (40 to 49 m). Measured pile sweep (lateral offset distance of the pile toe from the pile top) was between 12 and 17 inches (305 to 432 mm). Static load testing indicated that the piles could support the design load with axial deflection of less than 1 inch (25 mm) but only provided about 80 to 90 percent of the ultimate resistance at axial deflections of about 1.9 to 1.7 inches (49 to 43 mm), respectively. The other project, located in Shakopee, Minnesota, used 9.625-inch (244-mm) diameter pile but with a wall thickness of 0.352 inch (9 mm) and lengths around 50 to 90 feet (15 to 27 m). The measured sweep varied between about 20 and 63 inches (508 and 1,600 mm) for 9 of 214 piles driven at the site. Load testing indicated that these piles could provide the required design resistance with less than 0.3 inch (8 mm) of axial deflection and support the required ultimate resistance with about 0.5 to 0.6 inch (13 to 15 mm) to of axial deflection.INTRODUCTIONAnyone who has observed a significant number of piles has seen that, inevitably, the pile is not perfectly straight after driving. In spite of the best efforts of contractors, there are a whole host of reasons for piles to end up out-of-plumb or to have a curve, sometimes referred to as pile sweep. Most project specifications set limits for plumbness typically between 0.25 in/ft (21mm/m) and 0.5 in/ft (42mm/m) (USACE, 1991; PDCA, 2007; MnDOT, 2016; MoDOT, 2016). Closed-end pipe piles, including monotube or tapertube, are the only pile type that allow actual measurement of the final alignment of the pile.As Nadeem, et al. (2015) note, buckling failure of long, slender piles is the predominant mode of pile failure in soft soils. Pile sweep is just one source of buckling failure in long, slender piles. The nonlinear buckling analysis showed that increasing slenderness ratio and/or increasing degree of curvature decreases the loadcarrying capacity of a driven pile. Nadeem, et al. (2015) considered solid, steel pile with lengths from 24 to 66 feet (7.5 to 20 m), diameters from 9.75 to 26 inches (244 to 660 mm), initial bends from 2 to 6 inches (50 to 150 mm), and half- and quarter-sine shapes."

Jan 1, 2017

"Chairman: Professor J. Elbrond Rapporteur: Miss V. E. MartingPapers.Aids to planning production in coal mines by F. H. Deist and M. P. RobertsCapacity calculations, investment allocation and long-range production scheduling in German coal mines by F. L. WilkeOre reserve evaluation and open pit planning by J. M. Marino and J. P. SlamaThis session was devoted to the economic aspects of planning and scheduling. After Dr F. H. Deist had introduced the paper Aids to planning production in coal mines, Dr T. V. Falkie summarized the following formal contribution prepared jointly with Dr R. V. Ramani, describing the work that has been done at the Pennsylvania State University in the development of simulation programs for mine planning over the past 15 years:During the late 50's and early 60's, Monte Carlo simulators were developed to model continuous miner-shuttle car transport systems, track haulage systems, belt conveyor networks, etc. In the mid-60's attention was directed towards deterministic simulation of equipment performance, given the equipment characteristics and the system profile. In the late (10's all these systems (miners, shuttle cars, belts and trains) were integrated together to form a complete coal mine simulator and the program could predict the output potential of the system, given the mining dimensions, method and equipment employed. The actual sequence of coal-cutting operations is entered into the computer through the use of a special programming language which permits any type of mining configuration to be simulated. The simulator is hybrid in nature in that the shuttle cars, trains and belts are simulated deterministically, whereas rate functions with delay frequencies are entered for the continuous mining operations of sumping, shearing, fleeting, cleaning, etc. With suitable manipulation of the data, the program may be applied to all belt or conventional mining sections. Most of these simulators were developed through the assistance of grants from the Department of Mines and Mineral Industries of the Commonwealth of Pennsylvania and are available from the Coal Research Board of the Commonwealth,"

Jan 1, 2014

By G. F. Zhang

Yunnan mineral is a kind of containing Ta-Nb rare earth deposit, the most potential economic valuable element in it is Sc, and raw mineral has 17.0 g/t Sc. Take the character of Sc into account, the key problem in producing scandium chloride molten salt by adaptive technology is how to man-ufacturer anhydrous scandium chloride molten salt. During the course above, the key problem is that preventing Scandium chloride from being hy-drolyzed into ScOCl. The ScOCl content of molten salt not only affect purifying scandium but al-so do harm to the production of Mg-Al alloy. In order to restrain the creation of ScOCl, add ammo-nium chloride into molten salt. As long as ScOCl is created, it would be chloridized. Thus, during the course of dehydrating anhydrous chloride molten salt this method prevents scandium from hydrolyzing. Accordingly, the key phase of this producing course is eliminate ammonium chloride and the surplus crystal water, and the most crucial of it is restrain scandium chloride from being hydrolyzed into ScOCl. This research analyzed the theory that ammonium chloride is trend to be hydrolyzed into ammo-nium chloride, and propose the research scheme of restraining this process from creating ScOCl. The new process of restraining the generating of ScOCl and dehydration for crystal water rare earth chloride is adopted: Inert gas temperature increases rapidly to a certain degree to eliminate ammonium chloride and crystal water. The experimental research were done such as : the temperature of eliminating ammonium chloride and crystal water, amount of ammonium chloride, time, temperature growth speed, influence of inert gas flow toward to scandium percent hydrolysis, whereby, we conclude the optimal process condition in this period: Temperature: 400°C, proportion of oxidized scandium and ammonium chloride is 1:1.5(Proportion of oxidized scandium and additional salt is 1:5.4), time is 120minute, temperature growth speed is 10?/min inert gas flow is 5L/min.

Jan 1, 2014

By D. M. Soboroff

Etchants containing hexavalent chromium and sulfuric acid are used in a variety of surface-finishing operations. When the resultant spent solutions are discarded, substantial quantities of chromium are lost and pollution prob¬lems are created. To minimize the undesirable environmental effects while improving metal and minerals recycling technology, the Bureau of Mines is conducting research on a method for the economic inplant recycling of these waste etchants. Trivalent chromium, produced when the etchant reacts with a sub¬strate, is oxidized in the anode chamber of a diaphragm cell; other metals, dissolved during the etching operation, are transferred to the catholyte. When waste brass etchants are treated in this manner, all of the trivalent chromium is oxidized and more than 40 percent of the copper and zinc is removed. Similar copper removal and chromium oxidation are achieved with waste printed circuit board etchants and rinse waters from plastic etching operations. The electrical energy needed to regenerate 1 kg sodium dichromate is less than 9 kwhr. Regenerated brass etchants evaluated by two companies equaled or exceeded the performance of fresh etchants.

Jan 1, 1979

By Cindy Schiewek

Industrial injury occurrences are an ongoing concern for Mine Operators. Along with the personal suffering of injured workers comes an increase in compensation and productivity costs. Growing recognition of repetitive stress and bodily injuries, accompanied by recent studies, validates the assumption that a relationship exists between ergonomic injuries and machine design. Intuitively, there is a belief that an ergonomically designed machine will reduce repetitive stress injuries through design and education however; quantifying this belief has been a challenge for Mine Operators. Sandvik Tamrock has undertaken a project aimed at developing a business model to assist in quantifying the benefits of ergonomic intervention. This model focuses on distinguishing and quantifying this method of intervention to allow for a better evaluation of the machine. For simplicity, the project initially focused on the Face Drill Jumbos. The target of the project was three fold: !" Recognition of the cost drivers for compensation; ergonomic injuries !" Identification of the relationship between ergonomic machine design, and the decrease of the negative effects associated with the cost drivers !" Systematic prioritization for ?prevention by design? The project findings substantiate the expected reduction in injuries and compensation claims. Based on all ergonomic intervention studies conducted, each case showed a reduction in compensation cost; through prevention by design, one can reduce the amount of potential risk. The paper addresses the resources and methodology used, along with the findings and its relevance to the issues that face the Mining industry.

May 1, 2003