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By B Morey, J Gordon, P Mackenzie

Mount Tom Price Mine is peerless amongst Rio Tinto iron ore resources around the world. It has provided Hamersley Iron with premium quality, high lump yield haematite ore over the last four decades. The Brockman type bedded ore, containing bands of haematite and shale of varying thicknesses has been traditionally bulk mined to either high-grade or low-grade based on alumina cut-off grades. As open pit mining has progressed deeper into the orebody approaching the keels of the megastructure, increased structural complexity, chemical and physical variations in the ore, unfavourable ore presentation and reduced blending options have become an issue for grade control and may have serious impacts on product stockpiles. The grade blocks and boundaries must be accurately defined according to geological contacts and where identified, selective mining may be applied. Therefore in-pit geological mapping is the definite and ultimate guide to achieve target grades and grade predictions. Under this scenario, it is absolutely vital that the mine geology team ensures this geological knowledge is passed onto the related departments including mining crews as well as to the short- and long-term planners.

Jan 1, 2002

By J. W. Thompson

CONSTRUCTION OF STATUTE-SALE BY ENTRYMAN. The timber and stone act (20 Stat., 89) does not forbid an entryman from alienating his interest in his claim; but the act makes illegal any prior agreement by which the entryman acts for another in the purchase. Worden v. United States, 204Fed., 1, p. 4, April, 1913. ASSUMPTION OF DEBT BY GRANTEE-LIABILITY TO CREDITOR OF GRANTOR. A grantee of a mine who agrees to pay the grantor's debts in part payment of the purchase price of the mines becomes to that extent the principal debtor, and the grantor becomes the surety, and the grantor's creditor may in equity enforce his claim against the grantee of the mine, and the grantor in such a case is not a necessary party. Silver King Coalition Mines Co. v. Silver King Consolidated Mining Co., 204Fed., 166, p. 169, April, 1913. RIGHT OF COTENANT TO MINE AND SELL. A cotentant in exclusive possession' of mining property who extracts and sells ore is entitled to charge against the proceeds of the sale the reasonable and necessary expense of its extraction and marketing, as in such case the cotenant is not a trespasser.

Jan 1, 1914

By K-O. Mickelsson, S. Töyrä, H. Esbensen

Accurate information of physical, chemical and metallurgical quality characteristics such as moisture content, iron grade and particle size are crucial for successful process control and for producing products within customer specifications. Correct moisture content of pellet feed is an important variable for successful balling of iron ore pellets and to minimize power consumption in the sintering process. Control of the filtering process in the pelletizing plant is therefore essential for both productivity and high product quality. The current measurement systems for moisture content at LKAB are based on two types of manual grab sampling, subsequently analyzed with rapid moisture determination methods. Previous studies of the measurement systems have indicated high sampling variability resulting in lowered possibilities for successful process control. The objective of the present study is to evaluate an alternative filter sampling approach and testing of on-line Infra-Red analysis (IR-analysis). On-line IR-analysis has the advantage of eliminating physical sample extraction and allowing for continuous monitoring of moisture content. However, this approach is sensitive to the surrounding environment, making careful calibration and control crucial for the quality of measurement results. Furthermore, as IR-sensors only target the surface of the conveyed pellet feed, several incorrect sampling errors need to be considered and counteracted to eliminate sampling bias and reduce the remaining measurement variability. Variographic characterization was applied to the two current grab sampling approaches of combined filtered material, to the alternative filter sampling method, and to the On-line IR-analysis. The results indicate that both the sampling of separate filters (using composite sampling and ISO-standardized moisture analysis), as well as a calibrated and well- maintained IR-sensor can improve the relative variability significantly, by lowering the total measurement system variance from 60% to 25%.

Jan 1, 2018

By D. A. Poukhovski

Two integral components of the 30 CFR 48 training requirements mandated for new miners, newly employed experienced miners, and the annual refresher training of all miners are hazard recognition and prevention of accidents. In these categories, instruction shall include the recognition and avoidance of hazards present in the mine, and a review of accidents and their causes. Unlike instruction preparation for fact-based material, program development for hazard recognition places a particular challenge before safety-training specialists because they are often limited in their ability to adequately gauge the trainees' levels awareness prior to training. Further, they must also assure that the training is relevant, and it is presented in a thought-provoking manner. Computer-based instruction is particularly well suited for assisting trainers in developing hazard-recognition topics because it can be used in pre-training and post-training modes for assessment of training effectiveness, in addition to use as a presentation tool. Therefore, this paper will present a recent approach developed at Penn State to apply this technology for assessment and instruction of accident prevention through hazard recognition, with an application prepared for surface coal mines.

Jan 1, 1997

By Marco Larghi, Jurg Knobel, Braden Schmidt

Remote Avalanche Control Systems (RACS) which uses solid explosives has been used in Europe since 1996 and North America since 1999. With large destructive avalanches in transportation corridors, various States and Provinces have started implementing RACS into their summer construction projects to minimize traffic shutdowns. Since 2014 in North America, many of the projects are requiring the RACS deployment boxes to be removable by light duty helicopter for loading and summer storage. This is to further remove workers from the mountain tops, where inclement weather and Occupational Health and Safety concerns are widespread. We did not believe the method of flying primed charges under a helicopter was safe, so we developed a new charge container to deal with the issue. In spring of 2016, the Inauen Schatti company of Switzerland started the development of a flyable RACS deployment box to complement their 2 stand alone tower systems. To go along with the new flyable deployment box, a new S-Load charge carrier was developed. The newly developed and patented S-Load explosive charge for the LM32 RACS system features a mechanism which combines the explosive and priming material just before the blast. These are stored separately during transport and storage in the LM32 RACS deployment box. The S-load is divided into two parts. The upper part contains the plastic bobbin and ignition sequence (impact pull wire igniter, safety fuse and #8 blasting cap), whereby the explosive material and detonating cord are positioned in the lower part of the explosive container. The explosive material and ignition sequence are separated by a certified housing during transport and storage. The key idea of the S-Load system was to achieve a maximum level of safety by keeping the priming components separate from the explosive material until just before detonation. Because of this the S-Load and the LM32 tower remains safe during transport by helicopter or when being stored in the deployment box on the mountain side in the avalanche start zone.

By P. J. Best

Due to its low mine production costs, competitive rail rates and low sulfur content, the Southern Powder River Basin (SPRB) now commands 30 percent of the U.S. utility coal market. In 1996, production exceeded 260 million tons, a growth of 110 million tons since 1989 and 15 million tons over 1995. Continued growth is expected as the second phase of the Clean Air Act Amendments (CAAA) looms. This growth will be the greatest in the southern part of the basin, where coal quality is higher. This article is an overview of supply and demand issues affecting markets for SPRB coal. It reviews the current markets for SPRB coal and addresses future prospects for market expansion.

Jan 1, 1998

By G. R. Peeling

The Mining Association of Canada launched the Towards Sustainable Mining initiative in 2004. TSM's goal is to improve the mining industry's performance by aligning its actions with the priorities and values of Canadians. The initiative currently includes performance indicators for four areas: tailings management, energy use and greenhouse gas management, external outreach and corporate crisis management planning. Over the past year, the association has been designing a performance assessment and verification system for these performance areas, as its members prepare to move external verification of their performance in 2007. The initiative and its evolution, as well as the challenges faced in developing a verification system applicable to an entire sector will be examined.

Jan 1, 2007

By V. Ramachandran

Under the Resource Conservation and Recovery ACT (RCRA), generators of listed or characteristic hazardous wastes must find satisfactory means for disposal. of wastes. Initially, for many this meant landfills and deep-well injection. Until recently, mining and metallurgical by-products have largely been exempt from RCRA, but now are coming under its jurisdiction. With the increasing closures of landfills, companies in the U.S. such as electroplaters, miners, metallurgical plants and others are turning to recycling as an alternative to treat their wastes. While the cost of recycling has been challenging, the long-term economics prove attractive because recycling interrupts the cradle- to-grave responsibility for the waste generator. The present paper describes the recycling of hazardous wastes at ENCYCLE/TEXAS. Encycle extracts marketable metals from metal-bearing sludges and wastewater using hydrometallurgical processes borrowed from the mining and metallurgical industry.

Jan 1, 1994

By Frank Hirthammer

Since the introduction of the Explosives Track & Trace in Europe in 2014 for manufacturers and 2015 for end-users, a lot has changed in all areas of the supply chain and the use of explosives. The regional associations, manufacturers' organizations, and trade associations have proven that it is possible to overcome a hurdle, that looks almost impossible in the beginning, through consistent cooperation. The paper gives an insight into the problems involved in introducing such a requirement, identifies ways and solutions, and concludes them. When looking at the current situation, the paper describes the process by which a prescribed change in business processes are transforming into a solution that increases productivity, security, and handling.

Feb 1, 2020

By D Lucato, B Haase, R Saha, S Limberger-Forte, J Lishman

Cadia East Mining operations have employed geometallurgical techniques to advance the understanding of the in situ rock hardness variability across existing Panel Caves (PC). Geometallurgy advances the understanding of variability across an orebody through the integration of geology, mineralogy and processing response and therefore enhances spatial mapping of comminution or separation properties. Spatially extensive geometallurgical measurements are necessary so that continuous rock properties can be generated and used for the development of comminution and processing domains using geostatistical modelling. Standard testing protocol across geological and mineralogical domains is vital to understand the variability in deposit wide comminution and separation properties. The high cost and large sample requirements associated with metallurgical test work typically results in insufficient data density and distribution, making it difficult to model and map deposit scale variability. Quantitative hardness proxy tools are useful to measure in situ rock hardness, however this data is typically either sparse or missing within advanced mining operations. In recent years, mineralogy and multi-element assay data has often been collected as part of the standard geological data set and is generally coincident with metallurgical test work. In this paper relationships between mineralogy and comminution parameters have been applied to multi-element assay data with coincident measured Bond Work Index (BWi) data to generate a predicted BWi using linear regression. The predicted BWi is intended to supplement existing measured BWi data to enable better extrapolation across the deposit. Geostatistical Conditional Simulation methods have then used the predicted and measured BWi data to produce a BWi variable as a new input to the resource model. The simulated BWi can be used as an input for specific energy models to predict required grinding energy consumption across a deposit.

Mar 22, 2022

By Paul Riches

LR Process Expert is a cost-efficient process automation system for all types of long rolling mills, including, rod, bar, section, rail, reversing mills, and flat blocks. The system performs a wide range of tasks for optimized operation – from suggesting pass schedules to calculating and downloading optimized mill settings according to the availability of rolls. LR Process Expert also monitors and collects data from the raw material stage through to the finished product. It delivers valuable mill reports to the operator staff and management so they can easily assess a plant’s performance and optimize production. Defined Key Performance Indicators (KPIs) help to assess a plant’s performance; this system is not limited to one plant but can enable plant-toplant performance at corporate level.

Aug 16, 2017

By Paul Schmidt, John Barber

This paper discusses the determination of cutoff grade (COG), including all revenue and cost factors and how to apply the COG in the world of engineering studies and mine planning for underground mines. It provides the engineer with important considerations and practical methods to establish COG and methods of using the COG in the work of mine planning, including the application of Mineable Stope Optimizer (MSO) software which is available on several 3D mine planning packages.

Feb 1, 2024

By Javier A. Llano

GPS, wireless communications and on-board and off-board computing capabilities provide today’s mining companies with unprecedented process improvement and cost reduction opportunities. All aspects of the operation from engineering, surveying, drilling, loading, hauling and support can benefit from products like CAES and Drill Monitor. These technologies, which have been working at world class mines around the world in some cases for over three years, are helping customers achieve new lows in cost per ton. Manually intensive and time-consuming processes like in field surveying are replaced by timely mine status information wirelessly transmitted from the machines to the office.

Jul 17, 2000

By Joerg Hammerschmidt, Marcus Runkel, Andreas Wirtz, Kent Pope

"Fluidized bed reactor systems in the minerals industry have been progressively developed and widely implemented over a period of more than sixty years for a multitude of process applications. Their versatility is manifested in calcining, roasting and combustion treatment of minerals including solid fuels. Experiences from metallurgical processes have expanded to new applications in the oil shale processing, biomass combustion and renewable energy sector. This paper focuses on the most important aspects of fluidized bed technology for a variety of Outotec processes. Energy recovery is a major topic for all applications and will be addressed, as well as environmental aspects, particularly regarding the off-gas treatment. Outotec is one of the pioneers of roasting and the fluidized bed process including gas cleaning and sulphuric acid production where applicable. Process development is strongly supported by significant investment in R&D, thus enabling process adaptation and scale-up to meet specific customer/market requirements.Introduction to Fluidized Bed TechnologyThe early days of fluidized bed technology were characterized by the use of bubbling fluidized bed reactors (BFB). This technology was popular for roasting zinc and copper ores. The introduction of circulating fluidized bed technology led to increased plant capacities and improved process control for the traditional processes. Furthermore, the technology has been applied in many other industries, including the renewable energy industry, which will be part of this design and process comparison. The paper starts out with the fundamentals on particle fluidization as the main common design parameter, leading to the importance of heat recovery and offgas treatment.In fluidized reactor systems, the particle concentrations can reach several hundred kilograms per cubic meter of fluidization gas. This high solid concentration leads to large surface areas and enables direct contact of gas molecules with particle surface molecules. Excellent conditions for enhanced heat and mass transfer thus provide nearly ""ideal"" heat exchange conditions and better reaction kinetics. The bubbling bed exhibits a better heat transfer coefficient within the bed in comparison to the circulating fluidized bed (CFB). The different conditions of gas velocities and solid concentrations allowing the classification of fluidization reaction regimes are shown in the Reh diagram in Figure 1."

Jan 1, 2014

By Erik Sherer

Indonesia is poised to become a major player in the Pacific Rim thermal coal markets. Although the colonial Dutch developed numerous coal mines in the late 1800's for steamship bunkers and domestic fuel, Indonesia's coal industry has only recently begun to actively participate in the growing global marketplace. This export coal is primarily the result of the commercial development of coal mines in eastern Kalimantan by foreign contractors. From virtually no coal exports in the late 1980?s, Indonesia's coal industry has increased its exports to approximately 15 million metric tons (Mmt) in 1992. In 1992, Indonesia was the world?s sixth largest exporter of steam coal, By the year 2000, Indonesia projects that it will supply approximately 25 percent of the seaborne thermal coal requirements of the Pacific Rim countries. Although limited quantities of this coal may enter the European and U.S. markets, high qualities, low production casts, and favorable transportation rates will make Indonesian coals very competitive in the rapidly growing Pacific Rim markets. This study examines the Indonesian coal mining industry and compares it to the U.S. coal mining industry. This report is the sixth in a series of coal exporting country studies requested by the House Appropriations Committee. Previous studies examined the Colombian, Canadian, Australian, South African, Polish, and Venezuelan coal industries.

Jan 1, 1994

By Robert E. Wood

Engineers have known for some time that the efficiency of filtering iron ore concentrate slurry can be significantly improved by pre-heating the slurry ahead of the filters. However, heating such large quantities of dense slurry by conventional means has proven to be inefficient and high-maintenance. Recently though, submerged combustion was considered by Altos Hornos de Mexico SA (AHMSA), an integrated steel producer in the state of Coahuila, Mexico, as a means of pre-heating their iron ore concentrate. The company toured many iron ore facilities in Brasil and Labrador, reviewing their heating processes, and concluded that submerged combustion could provide a competitive advantage through operational efficiency and lower capital cost than steam boilers. Inproheat was retained by the company to design and manufacture a SubCom slurry heating system to heat 403 m3/h of iron ore concentrate slurry from 25°C to 60°C. The 60GJ/h SubCom system consists of five natural gas combustion chambers mounted in an iron ore concentrate storage tank. The system features a heat recovery unit whereby the exhaust gases are used to preheat the incoming slurry stream, giving the system an overall thermal efficiency of 95%. As a result, the steel company expects to realise significant improvements in filtering efficiency which will enable them to increase the capacity of their pelletising plant without installing additional filters.

May 1, 2010

By B. J. Sauer

Misapplication of AC induction motors for mine crusher and mill applications has long been a frustration for both the driven equipment supplier and the mine operator. Proper selection of AC induction motors is critical to providing efficient production. This paper focuses on the selection of AC induction motors for gyratory crusher, cone crusher, and grinding mill applications. The criteria for motor selection includes: proper enclosure, driven equipment torque requirements, bearing life, temperature rise, starting requirements, ambient temperature, altitude and accessory requirements.

Jan 1, 1999

By Frank Hirthammer

Since the introduction of the Explosives Track & Trace in Europe in 2014 for manufacturers and 2015 for end-users, a lot has changed in all areas of the supply chain and the use of explosives. The regional associations, manufacturers' organizations, and trade associations have proven that it is possible to overcome a hurdle, that looks almost impossible in the beginning, through consistent cooperation. The paper gives an insight into the problems involved in introducing such a requirement, identifies ways and solutions, and concludes them. When looking at the current situation, the paper describes the process by which a prescribed change in business processes are transforming into a solution that increases productivity, security, and handling. It shows examples from daily work, in which possibilities for optimization, improved quality assurance, and work facilitation are explained. It presents the resulting potential by comparing process flows, before and after the introduction of Track & Trace solutions. What challenges will we face in the future concerning the use of T&T solutions? Will the tracking of explosives become the norm worldwide? What are future hardware and software developments to be expected? What impact will this have on the global supply chain?

By R. Mukherjee

Consistency of Run-Off-Mine (ROM) quality plays an important role in mineral processing which is not very often talked about. The major impediment is limitation of sampling ROM ore, which makes processing plants to run without any realtime feedback on ore quality that comes in. The process of direct determination of Run-Off-Mine (ROM) ore quality is expensive and time consuming as drawing and preparing representative samples from blasted muckpiles are constrained by large sample size and inherent heterogeneity in terms of size and chemistry. In absence of techniques for direct measurement of quality, monitoring and control of ROM, feed to the processing plant at Joda East Mine, like all other iron ore beneficiation plants worldwide, is largely based on blasthole sampling and subsequent chemical analyses of blastcone chips. While such indirect methods proves to be more accurate for representing whole of a mining block or blasted muckpile (~30-50KT/blast), it is indeed a challenge to ascertain and predict day to day input quality for a part there off. This eventually leads to a gap between predicted and actual ROM quality, resulting in difficulties in process control, in turn, and leading to wide swings in product quality. Hence, it is imperative to bridge the gap between predicted and actual ROM quality by arriving at means, which ensure consistent plant feed grade to deliver consistent output. The paper discusses an efficient and affordable alternative for effective prediction of ROM alumina which has been developed by integrating blasthole quality database in GPS based Truck Dispatch System (GPS-TDS) at Joda East Mine. Initially, GPS-TDS has been installed for optimizing production parameters only, but this development has helped in further utilization of GPS-TDS for real time quality monitoring by improving ROM grade prediction and scheduling from several ore blocks in active mining areas. Keywords:run-off-mine (ROM), blast hole, feed grade, GPS-TDS

Sep 1, 2012

By Charles H. McGuirk

The movement of iron ore, limestone and-coal on the great lakes involves an intricate transportation network between mine, dock, vessel, railroad and consumer. The system requires that stockpiling be performed at certain points in the pipeline because of the seasonal closing of the lakes, traditionally, this has been accomplished at origin and destination with a substantial cost. Impact to both the shipper and consumer, From the time that the raw material is removed from the ground, expeditious handling and movement to final destination is threatened by a series of potential delays. An initial movement from mine or processing plant to the upper lake port must be coordinated between rail equipment and dock facility, As each vessel is loaded, a schedule must be developed which routes the cargo to an unoccupied lower lake port. However, if the vessel is not delayed by unpredictable weather conditions on the lake, the boat may still arrive at a port congested with other vessels awaiting their turn to unload.

Jan 1, 1973