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By Andre Pienaar, Larry Wilson, Clive Dawkins

The development of implementation of cost effective emulsion explosive and portable pumping system for the replacement of package explosives in the deep level gold mining environment. A number of versions of portable pumps will be presented, demonstrating continuous improvement on these systems. Data on reliability of units in the field will be presented.

Jan 1, 2009

By David G. Borg

Emulsions explosives, like slurries or water gels, are water based explosives. Emulsions were first introduced as a packaged blasting agent in the late sixties. Since then, many new variations have been developed, from small diameter detonator sensitive products to bulk loaded anfo/emulsion blends. Explosive detonation characteristics such as velocity of detonation, density/sensitivity relationship, strength, and water resistance along with how they relate to the type of rock and type of application will be presented. Various methods of sensitizing such as glass microspheres and chemical gassing along with product limitations and safety recommendations for bulk loading emulsions will also be presented.

Jan 1, 1994

By Dean L. Millar

Measures taken by mining companies around the world to reduce their carbon footprints are becoming increasingly important in the sector securing its social licence to operate. The options for measures reduce to three categories of activity: i) demand reduction by avoiding unnecessary waste of supplied energy, ii) improving the utilization of energy that does have to be consumed and iii) adopting low carbon energy production options?including renewable energy. As well as the environmental imperative, as the prices of electricity, gas and liquid fuels increase, so the economic case for activities i) to iii) gains higher priority, especially in such an energy intensive industry. The specific energy consumption for certain upstream minerals industry operations in Canada is reported to be as follows: underground mining: 99.5 kWh/tonne mined; surface mining: 11.7 kWh/tonne mined; base metal processing: 81.4 kWh/tonne milled; gold processing: 99.6 kWh/tonne milled. Around 508 kWh/tonne (slag) of heat is reported to be available in cooling slag from 1500°C to 25°C; an amount that is simply indicative of the energy intensity of downstream smelting and refining operations. Low carbon, energy saving technology options that are available to mining industry companies lead to projects with return rates that must compete alongside other capital intensive projects considered by mining company boards. Energy projects frequently involve longer payback periods and lower rates of return than those of competing bids for capital, such as those for development of new mineral properties. For energy services companies (ESCOs) that specialize in the financing, construction, and the efficient operation and maintenance of energy projects, the same returns and payback periods may be considered acceptable or even attractive. For the ESCO, the key commercial risk mitigating factor is a securing a long term contract for the supply of energy.

May 1, 2011

Automated drilling in surface mines is here, it?s successful, and it?s already at work in mines around the globe. Coal, copper, iron and gold mines in large mining countries such as Canada, Australia, South Africa, the United States and Chile are meeting mining objectives previously ruled out as unattainable. Pit Viper automation enables operators to accomplish more objectives safely. Operator assist functions like AutoLevel, AutoDrill, Auto Rod Changer and multi-rig teleremote control are a few of the features mines are using to gain consistent, sustainable productivity.

By B Hiebl, J Martens, L Petzold

A research team at the Iron and Steelmaking department at Primetals Technologies has established new upgrading measures for improving the efficiency of the beneficiation process in ironmaking plants, relying largely on pre-existing equipment. After the upgrade, the iron content in the final iron ore concentrate was shown to be significantly higher. Remarkably, the costs for employing the respective measures are surprisingly low.This case study is based on a Kazakh iron and steel producer, whose beneficiation process is currently generating a magnetite concentrate with a final iron content of 65.65 per cent. The study shows that the implementation of Primetals Technologies’ intelligent modification measures to the current beneficiation process, the realisation of more effective dewatering, and the utilisation of an innovative binder lead to an increased iron content in the resulting pellets, reaching a concentration of 69.17 per cent (iron ore concentrate) and 66.5 per cent (pellets).The current operation consists of three closed circuit grinding stages, four stages of low intensity magnetic separation, vacuum disc filters and straight-grate pelletising. By dividing the slurry after the second stage of grinding and the third stage of low intensity magnetic separation, it is possible to divert the more iron-rich fines before they would enter the third grinding stage and the fourth stage of magnetic separation. This then reduces the load on the existing third stage ball mill. Afterwards, the ground material is treated in an additional low intensity magnetic separator and mixed with the previously diverted fraction of the fines. An improved filtration procedure, combined with the application of a highly sophisticated binder, further reduces the amount of additives needed, so that a genuine direct reduced (DR)-grade iron concentrate is produced as a result.All laboratory, pilot and pelletising test work was executed at Primetals Technologies’ laboratories in Austria.CITATION:Martens, J, Petzold, L and Hiebl, B, 2017. Enabling iron ore concentrate for the production of direct reduced iron with pre-existing beneficiation lines, in Proceedings Iron Ore 2017, pp 227–232 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By E. Trickey

In the mining industry there exists a constant drive for increased safety and productivity and decreased operating costs. This acts as a driver for implementing advanced technology. As more and more mining operations turn to new technologies, an observed bottle-neck for technology advancement has been the limitation of machine vision solutions available. LiDAR has been seen as a possible solution to the machine vision problem. In the past, a few studies on machine vision solutions have been undertaken by various groups involving scanning laser range-finders and millimetre-wave radar. These studies have done little more than highlight the limitations of both technologies in the mining environment. Little work has been done, however, exploring the applicability of LiDAR imaging technology for mining applications. Neptec Technologies Corp. has developed an obscurant-penetrating LiDAR (OPAL) sensor technology which overcomes the limitations faced by traditional LiDAR sensors when operating in a dusty environment, as well as advanced 3D real-time intelligence (3DRi) data processing algorithms that enable the real-time exploitation of 3D imaging data with sensors mounted on moving vehicles. Working with Teck Resources Ltd. and Barrick Gold Corporation, Neptec is adapting the OPAL sensors and 3DRi technology to mining applications. This paper highlights a number of real-time OPAL/3DRi based mining applications demonstrating how this technology overcomes the limitations of traditional LiDAR to provide a real-time machine vision solution that supports mine machine autonomy.

Aug 1, 2013

Using a series-model of an automotive short range radar sensor (SRR) and a recently completed experimental radar system, field tests have been performed in a surface mine. It was examined, to what extent low-cost electronically scanning radar sensors can provide useful data for assistance systems on large scale mining machines. Simple sensors are useful for anti-collision safety zones or hopper car automation. The more complex and sophisticated experimental radar system using digital beam-forming can clearly detect and map the contours of trenches and slopes. The overall promising results refer to many more potential applications for electronically scanning radar in surface and underground mining as a reliable alternative to mechanical laser scanners.

Jan 1, 2007

By K. Bullock, M. Levesque, G. Lyle, D. L. Millar

ABSTRACT The options for reducing the carbon footprint of energy use in mining fall into three categories of activity: i) reducing demand, ii) improving energy utilization, and iii) adopting low carbon energy technologies. In addition to the environmental imperative, the economic case for these activities gains higher priority as the prices of electricity, gas, and liquid fuels increase. Low-carbon, energy-saving technology options that are available to mining industry companies lead to projects with return rates that must compete alongside other capital-intensive projects considered by mining company boards. Energy projects frequently involve longer payback periods and lower rates of return than those of competing bids for capital, such as new mineral property developments. For energy services companies that specialize in the financing, construction, efficient operation, and maintenance of energy projects, the same returns and payback periods can be considered acceptable or even attractive.

Jan 1, 2012

By Evelynn Stirling

"The paper/presentation will review the evolution of diesel technology from older diesel engines (1990 vintage) through to the latest technology as a result of the ever changing emissions regulations. It will encompass the EPA Tier levels as well as the latest Euro Stage V emissions. The next step with technology will be to address the CO2 emissions, which translates to improving fuel efficiencies of the product as well as other technologies like battery electric, hybrid and fuel cells. As technology progresses it also becomes important to improve connective diagnostic systems to support maintenance practices and improve efficiencies. What will also be presented will be the key emissions changes to the different gaseous and particle mass elements as the products have transitioned from the EPA Tier 3 through to Tier 4 Final regulations. Offering a range of different technologies to the underground mining market matters as not all pieces of equipment will perform optimally due to its duty cycle and application. INTRODUCTION Rudolf Diesel built his first well-known prototype of the high-compression engine in 1897. Since that time, the diesel engine has evolved into one of the world’s most capable and reliable forms of power generation. Diesel engines can be found in a wide variety of vehicles and equipment, powering everything from agriculture and construction equipment to power generators and marine vessels. In the early days the emissions from diesels was very poor and extensive work has been accomplished over the decades to make the product more environmentally friendly. This is more important in underground mining where the space is limited and ventilation is expensive and challenging. DISCUSSION The key driver of the development of diesel technology is the legislation globally around engine emissions. The emission level requirements over the years has forced diesel engine manufacturers to build a deep technical understanding of the system and how to innovate and optimize key elements of the engine. Cummins expertise has been built over the years as the diesel engine has evolved from a relatively simple mechanical engine to an electronic system with advanced air handling, fuel system, after treatment, and controls. Cummins has also continued to expand into systems beyond diesel, including natural gas. Many new components have been added to diesel engines to reduce emissions while improving fuel efficiency and reliability and, at the same time, reduce the total cost of ownership to the customer."

Jan 1, 2019

By C Fischer

The introduction of digital communications technologies into the underground mining industry, in both coal and hard rock mining, has enabled high bandwidth applications to be applied in the mining industry. Digital networks based on 802.11 b/g/n open Wi-Fi standards have allowed numerous applications to be run over a single communication backbone. One of the many important applications is the tracking of personnel and equipment via RFID Tags. This tracking application has formed the basis of a Proximity Detection System or Collision Avoidance System (Schiffbauer and Mowrey, 2001; Kent, Fischer and Schiffbauer, 2011) thereby improving safety and increasing control in the mining environment. This paper discusses the growth of digital technology as the backbone for communications in underground mining applications. This growth has allowed the ‘convergence of technologies’ (occurring in the general business world) to be available to mine operators in general and underground mine operators in particular. Mine Site Technologies’ involvement with major mining companies and mining equipment manufacturers (OEMs) in developing and supplying their communication systems is also discussed.The latest technical requirements and specifications for communication systems for underground and open cut mines will be reviewed.

Nov 22, 2011

By L. Gutierrez, R. Yepsena

Enargite in porphyry copper deposits is an important mineral as it displays good floatability under the presence of the collectors usually used in the flotation of copper sulfides. As a result, copper concentrates grades are reduced. As scarcity of water resources is a problem relevant to Chilean mining, the use of seawater is a feasible solution. The behaviour of copper sulfides and molybdenite in the process of flotation in seawater was previously studied but not for enargite. The objective of this research is to study the behaviour of the enargite in different conditions of electrochemical potential during the process of flotation using seawater. The study was carried through micro-flotation tests using pure samples of enargite, at Eh values ranging from -300 to 500 mV(SHE), both in seawater and aqueous solutions containing calcium and magnesium. The results show that at pH 10.5 in seawater, the enargite and chalcopyrite recoveries are reduced throughout the whole range of Eh studied. At pH 9 in seawater, enargite and chalcopyrite are depressed under reducing and slightly oxidising conditions. The recovery of both minerals drastically decreases at Eh values lower than -100 mV and greater than 400 mV. The behaviour of enargite in seawater flotation differs from that observed in conventional water, since in the latter case the recovery of enargite decreases at higher potentials close to 500 mV. Keywords: Enargite, flotation, seawater, redox potential

Jan 1, 2020

By Bryce Sullivan, Cliff Baratta, Ehsan Alavi, Timothy Dobbs, Lisa Mori

"Soil conditioning is one of the main factors in successful application of EPB machines in tunneling projects, which involves changing the characteristics of the ground in order to make it suitable for the tunneling process. Selection of the type of conditioner mainly depends on soil type, properties of the tunnel boring machine, and most importantly geological condition. Proper EPB tunneling and soil conditioning in ground above water table is challenging. This was encountered in Northgate Link Extension Tunneling Project in Seattle, WA. In order to improve the tunneling operation, a novel algae-based encapsulated oil was used as a conditioner and as a result the operation of the TBM was improved significantly. This paper reviews the traditional soil conditioning measures that were adopted in University Link and Northgate Link projects in Seattle, WA and compares the results with results when using the encapsulated oil additive. INTRODUCTION Soil conditioning agents are used in EPB tunneling to transform the excavated soil into a workable paste with the desired hydrological and mechanical properties. Reducing wear, power consumption, friction, adhesion, and improving the face stability and material flow are some of the benefits of using soil conditioners in EPB tunneling. Soil conditioning is performed by injecting foam, polymer, water, and bentonite to the tunnel face, excavation chamber and screw conveyor. Selection of conditioning agent mainly depends on soil type, geological condition (groundwater and soil permeability) and TBM features (injection points, open or closed cutterhead, type of foam generator, etc). The most widely used soil conditioners are foam and polymer and in some cases due to existing conditions, clay dispersion or anti-wear additives are also used (Milligan 2000, Langmaack 2000). Foam. Foam is created by dispersing air in a surfactant solution. A different combination of surfactant type and foam parameters should be used for different soil types. Laboratory tests on virgin soil should be performed to identify the best surfactant and foam parameters for the specific soil type (Langmaack 2000). The foam parameters can be described as follows:"

Jan 1, 2016

By A. D. Davis

Limestone-based technology for arsenic removal from water is an innovative and promising method. The technology offers the potential for low-cost disposal of a stable waste product after arsenic removal, either in an ordinary landfill or by encapsulation in concrete. Leaching research described in this paper shows that the limestone waste, after encapsulation in concrete, passes the Toxicity Characteristic Leaching Procedure (TCLP) test. Leaching was less than 0.05 mg/L, which is 1/100 of the U.S. EPA?s standard for disposal of arsenic in a landfill. Disposal of arsenic-enriched waste is critical for commercial viability of arsenic-removal technologies. Low-cost disposal gives the limestone-based method an advantage that could help communities meet the new maximum contaminant level of 10 parts per billion for arsenic in drinking water. The ability to recycle the waste material in concrete could add a significant economic benefit, further reducing overall costs.

Jan 1, 2009

By Robert Harris, Peter Pheeney

"The Murray Brook gold mine operated from September 1989 to March 1991. Approximately 1.2 million tonnes of gossan were mined from an open pit and treated at a rate of 900 tonnes per day. The facility applied an agglomeration vat-leaching cyanidation plant for gold and silver recovery. The leached ore or tailings were rinsed of residual gold and cyanide and placed on an adjacent clay lined pad for storage and containment. A 50,000 tonne heap-leach demonstration project was constructed at Murray Brook in 1992 to recover copper and zinc from ore located in a sulfide-rich zone occurring beneath the gossan. The operation proved unsuccessful because of poor recoveries and low metal prices. The project terminated in the same year.A corporate decision was made in September 1999 to undertake complete and final reclamation of the Murray Brook site. Jacques Whitford and Associates Limited were contracted to develop the final reclamation plan and to assist the company in presenting the plan to the New Brunswick government for approval. The government approved the plan in January 2000. Two important reclamation issues were the mobility of mercury from the gossan tailings and the potential of acid mine drainage from exposed sulfides. The mine site is situated upstream of a productive river system, and the issue or impact of chemistry changes to the environment over the long term became an overriding factor in the development of the reclamation plan.A resource assessment of the gossan tailings in 1999 indicated an average concentration of mercury of 40 ppm. The mercury occurred naturally as the mineral cinnabar, but the exposure to residual cyanide (less than 10 ppm) over several years in the pile has likely caused much of the cinnabar to decompose into more soluble mercury forms. The reclamation plan specified the replacement of all sulfides to the pit followed by approximately 600,000 tonnes of gossan. To ensure “fixing” of the mercury, the gossan was replaced in compacted lifts and both the remaining pile and that replaced to the pit covered with available till and compacted. The reclamation work was successfully completed in September 2000 and the chemistry of the receiving environment will be monitored over a three-year period, after which the company expects to achieve walk away conditions."

Jan 1, 2001

By Simón D. Strauss

Dada la demanda de los recursos minerales en las industrias productoras de metales, surgió el temor de un posible desabastecimiento de los mismos. Sin embargo, el abastecimento potencial de minerales y metales básicos es tan vasto que se satisfacen todas las demandas. En este sentido, el presente trabajo describe una visión panorámica sobre el proceso de la demanda mineral desde fines de la Segunda Guerra Mundial hasta el año de 1978. La revisión considera el proceso de demanda en cuatro zonas principales: Estados Unidos, los otros países industrializados con economías de mercado, los países socialistas con economías centradas y los países en desarrollo del Tercer mundo. Asimismo, se remarcan las posibilidades de fuentes de desarrollo de los países latinoamericanos en torno al mercado mineral a través de una financiamiento adecuado y de la habilidad y conocimientos tecnológico de sus líderes para formar parte de una sociedad industrializada.

Nov 20, 1978

By Patrick A. Ley

Maintaining, managing and manipulating large quantities of geologic data can be a very costly and time-consuming process. The use of computer-based methods can provide some relief to the problems of editing, displaying, and interpreting spatial geological data. ENCORE is a system designed specifically for coal orebody modeling and reserve esitmation where the geologic data is stored on a large mainframe computer and is accessed from a local work station for editing, manipulating, and producing various reports and high-quality engineering maps. The ENCORE system was designed for use by the geologist or mining engineer with little or no computer background and, additionally, it was designed to provide the geologist or mining engineer enough flexibility to be able to select the appropriate methodology for the orebody being analyzed. The various analysis tools incorporated into ENCORE can significantly increase the professional's productivity without burdening he or she with the need to understand the details of the internal computer language.

Jan 1, 1982

By Dirk Voogt, Quentin Steyl, D. Scott Scovira

A South Africa iron ore mine reported a decline in blast performance and ore and waste fragmentation. Preliminary investigation by the explosives services company found that the straight gassed bulk emulsion was breaking down and collapsing inside of some loaded slept blastholes. The bulk emulsion loaded at the subject site was manufactured in country and shipped to various clients throughout the region, with normal function in blasts at other sites. Historically, the bulk formulation emulsion being used at the subject mine site also performed well and without issue. This raised the question, “why is this bulk emulsion now breaking down and not firing in blastholes?”. Iron ore mines are not typically associated with reactive or acidic ground, and ground sample reactivity testing against the emulsion confirmed this. So, if not reactive ground or acidic water, then what is causing the emulsion to breakdown?

Feb 6, 2023

By the courtesy of Sir Robert Hadfield, we have received the fol¬lowing communication relating to the development and encouragement of science and research in Germany at present. These statements have been translated by Sir Robert from various German sources, and are presented here as an indication of what Germany is doing not only to further her military power, but also to prepare for the period of trade rehabilitation to which she is looking forward after the close of, the war. KAISER WILHELM TRUST FOR PROMOTION OF WAR SCIENCE The Kaiser has approved the foundation of a Trust with the name given above. The aim of the Trust is to further the development of scientific and technical aids to warfare, by uniting the scientific and the military forces of the country for work together. The scientific Work is to be carried on by the following technical committees (or commissions) (1) Committee for the chemical raw materials, for the production of munitions-manufacturing materials. (2) Committee for chemical war materials (powder, explosives, gas, and the like). (3) Committee for physics, including ballistics, telephony, telegraphy, determination of targets and distances, measurements, and the like. (4) Committee for engineering and communication. (5) Committee for aeronautics. (6) Committee for obtaining and preparation of metals.

Jan 8, 1918

By M. C. van Blerck

This paper examines the South African fiscal system as it applies to the mining industry and, where components are found wanting, discusses possible alternatives. It is concluded that the South African system has long provided a stable environment for mining investment and growth. However, the introduction, of steep surcharges during the past decade or so (since abolished) and ring fencing (since relaxed but not abolished) has started undermining this stability.

Jan 1, 1994

By Robert H. Peters

How can employees be stopped from engaging in unsafe work practices? It is often easier to prevent employees from performing unsafe acts through manipulations of the work environment than through various training or motivational programs. Therefore, it is important that accident prevention programs seek to identify the reasons for the unsafe behavior and to redesign tasks and the work environment (e.g., tools, equipment, physical surroundings) in order to remove employees from sources of harm and to prevent situations from arising that would prompt them to perform unsafe acts. Unfortunately, in the mining industry the work environment is often innately hazardous, rapidly changing, and difficult to predict, making it very difficult, perhaps impossible, to fully protect the employee by environmental manipulations. Therefore, it is important that effective methods be identified for influencing mine employees to work safely. Various strategies have been used to convince employees to avoid unsafe acts and/or adopt self protective behaviors. The intent of this article is to provide guidance to mine operators concerning the use of four techniques for influencing mine employees to work safely: (1) employee surveys, (2) incentives, (3) fear communications, and (4) disciplinary actions.