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By D. P. Goodall

THE development of the oil and gas resources of Western Canada is not, as many suppose, a new industry. For more than half a century an intensive search for these valuable products of nature extended from near the western edge of the Precambrian Shield to the Pacific coast, and from the International boundary north to the Arctic circle. The chief centre of interest to the oil prospector has, however, always lain in that region lying east of the first range of the Rocky mountains and confined largely within the boundaries of the Province of Alberta. Although there are many geological problems yet to be worked out in this Province, the oil-well driller has helped in no small way in determining sub-surface conditions and distribution of rock formations. The chief geological conditions as they affect the drilling of wells are generally re-cognized, and for this purpose the Province may be partitioned into three main divisions: first, the disturbed belt or foothills region extending along the eastern edge of the Rocky mountains; second, the Alberta geosyncline, a broad trough lying to the east of and parallel to the disturbed belt and from which the formations rise eastward to level off and form, third, the plains ? ? region, extending over the rest of the Province. A relatively small area in the northeastern part of the Province is underlain with Precambrian rocks and may be excluded from this classification, as it is of no interest to the oil prospector. The foothills, or disturbed belt, has presented the greatest difficulty to drilling, though it has produced the largest yield of oil within the Province to date. Within the foothills belt, the rock formations consist largely of hard shales interspersed with layers of abrasive sandstones, which wear out drilling bits at an alarming rate. The strata, in most flaces, dip steeply and are cut by numerous thrust faults. Although some o the faults have great displacements, their presence may easily be overlooked or the extent of the fault misinterpreted. Many a prospect well has been located on what appeared to be a suitable geological structure only to find, after drilling through a normal succession of rocks for 4,000 feet or more, that the drill had passed through a major fault plane to a younger formation than that in which drilling was started. Only a repetition of formations already drilled could be expected at greater depths.

Jan 1, 1942

By K. E. Haque

"Radium is selectively leachable from uranium ores with various types of lixiviants. Among a number of lixiviants tried on Midwest Lake uranium ore, KCl provided the highest per cent of radium extraction (60%-65%). Leach results further confirmed that a certain portion of Ra is not amenable to KCl leaching. More than 99% of the dissolved radium could be removed by treating the KCl leach liquor with barite or with radium selective complex resin (XFS-43230 resin of Dow Chemical Inc.) or by precipitating as RaBaSO4. Uranium leachings from the Ra-preleached uranium ores indicate that radium leaching prior to uranium may be applied as an extension to the conventional or alternative (i.e. acid chloride) leaching process of uranium ores in order to yield environmentally acceptable tailings (in terms of radium in the solids).IntroductionAt present, radium is considered as an environmental issue, particularly for uranium ore mine mill operations, rather than a commercial commodity. Radium was once a highly priced commodity ($180/mg during the first great war) but now it hardly has any commercial value. Its principal applications were in the field of cancer treatment and in the manufacturing of lwninous dials for watches. Nowadays readily-available synthetic radioisotopes are finding applications in place of radium.Because of scarcity and high toxicity, further commercial applications have never been explored.Radium was first discovered and extracted from uranium ore by P. Curie, M. Curie and G. Bement in 1898. Radium is widely distributed in nature but in exceedingly minute quantities. It is one of the daughter products of uranium or thorium and its maximum concentration is 3.3 x 10-7 part/part of U(21). Because of its short half-life (approximately 1620 years) in a geological time scale, its occurrence in nature as a distinct mineral is most unlikely.The details of the original radium leaching process developed by the Curies and Bernont are in the literature. This process essentially involved the roasting of uranium ore with caustic. carbonate followed by sulphuric acid leaching. The precipitated RaSO4 and BaS04 were treated with boiling Na2CO3 to convert them into the corresponding carbonates which later were dissolved in HCI. RaCI2 and Ba02 were separated and concentrated from the chloride liquor by fractional crystallization. But, in the course of time several modifications were made or proposed to the original process. Regardless of the process employed 226Ra extraction from the uranium ore was seldom better than 90%, and further as much as 20% 2URa loss took place during the concentration and purification process."

Jan 1, 1987

The morphology of environmentally assisted cracks in stressed pipeline steel has been investigated, For a dilute and neutral solution (NS4) simulating ground water in contact with the steel, semi-elliptical cracks grow faster on the surface (2c) than in the depth (a), hence, the aspect ratio (a/c) decreases, This is explained using a deterministic concept since corrosion is dominant and the primary constraint is the conservation of charge, By contrast, when mechanistic conditions prevail, significant growth occurs in the depth, When underloads are imposed in the loading history, temporary accelerations in crack growth occur because corrosion rather than mechanical effects become dominant.

Jan 1, 2005

By S. Haggarty, R. Walton

Barrick's growth and development plan will add three major new mines during 2005 including the Lagunas Norte Project in the La Libertad Province of Peru, the Veladero Project in the San Juan province of Argentina, and the Tulawaka Mine in north¬western Tanzania. Lagunas Norte and Veladero are similar in that they are both green-field open pit deposits at elevations over 4,000 meters above sea level, with two stage crushing and heap leaching followed by Merrill Crowe zinc precipitation for precious metal recovery. Operating sites will each generate in excess of 700,000 ozs Au per annum with commissioning and full scale operation planned during the third and fourth quarter of 2005. Details with regards to regional geography, development schedule, production and process specifics for Lagunas Norte and Veladero will be discussed in this presentation providing an overview for the respective properties.

Jan 1, 2005

By G. Gu, B. Fang, R. W. Revie, M. Elboujdaini

Electrochemical behavior of an X-80 pipeline steel, including frequency-sweep electrochemical-impedance spectroscopy (EIS), time-sweep EIS at a constant frequency and open-circuit potential (OCP) monitor, was investigated using four-point bending specimens subjected to a stress-corrosion cracking (SCC) test in a near-neutral pH environment. The capacitive loop became smaller with test duration, revealing an increase in the corrosion rate. The resistance obtained in the constant-frequency EIS test showed two regions, of which the region with a remarkable decrease in resistance transformed into a region of slow decrease, whereas the capacitance increased with test time indicating that iron dissolution was fast at first, and then a corrosion product or film formed and covered the surface, leading to the pitting formation.

Jan 1, 2005

The quality of refractory bricks and castables could be determined by direct measurements of their material properties such as elastic properties, porosity, density, etc. using conventional static or non-destructive testing (NDT) dynamic techniques. Quality monitoring of refractory linings is much more challenging and complicated. The static methods require undesirable drilling and sample extractions from the furnace structure. A more desirable alternative is the use of NDT techniques for material quality estimation. The Acousto Ultrasonic-Echo (AU-E) technique is a new stress wave propagation approach for monitoring the quality of refractory linings in operating furnaces. In this paper, the conceptual methodology for the AU-E technique is described, the capabilities and limitations are expanded, and the results from two case studies are discussed.

Jan 1, 2005

By D. Ofstie, B. Kargutkar

BIM, or Building Information Modeling, is transforming the way metallurgical facilities are built, operated and maintained. BIM provides a digital representation of the facility, complete with all physical and functional characteristics - enabling collaborative planning, concurrent design, construction simulation, sustainable operations and predictive maintenance through a connected information model. Building on experience gained in other industries, Hatch is aggressively applying the BIM process to the mining & minerals processing industry to address inefficiencies inherent in traditional document-based information management. Intelligent 3D models support real-time quantity forecasting and cost trending by commodity type and construction work package. By linking procurement and schedule data, material availability and constructability reviews are visualized to verify construction critical path, ensure work front safety and minimize craft downtime. The BIM digital information model connects engineering, construction, commissioning and vendor data, aiding timely asset-centric handover to plant operating and maintenance systems.

Jan 1, 2015

By Glenn Davis

In the world of large scale open pit mining, the majority of a mines operating cost is tied to the removal and transportation of the overburden waste material. Typically, many large haul trucks are employed to transport this overburden from each excavating face. The trucks transfer the waste material from deep within the pit to waste dumps on the surface incurring significant costs in operators, road construction and maintenance, vehicle maintenance staff and support facilities, fuel, tires, and spare parts, as well as the capital cost of the truck fleet itself. In addition, the haulage of the actual mined material carries similar operational costs. In both cases, these costs grow as the mine face advances and pit haulage distances increase. Reducing truck haulage is one key to the success of the Dual Truck Mobile Sizer (DTMS). Being the world?s first fully mobile truck dump station, transportation costs can be significantly reduced as the mine face advances. Furthermore, when used in conjunction with a shiftable face conveyor and a mobile overland hopper, substantial cost savings can be achieved. The mobility of the system allows for the considerable reduction in the haul truck fleet. Overall mine site emissions levels are greatly reduced by the fleet elimination, as well as keeping the majority of the hauls on a flat grade within the pit. Emission levels on a typical truck will dramatically spike as the angle and the length of the haul are increased. Moreover, comparing diesel engines versus electric powered conveyors to move the material contributes to the realized savings.

May 1, 2010

By S. Vézina

"Environmental issues have evolved considerably over the last two decades. The main contributing factors, to name a few, have been the changing values of modern societies, the globalization of trade and its linkage to environment, evolution and accessibility of information/ communication technologies, better educated populations, climate change, longrange transport of toxics, and the increasing influence of non-governmental organizations (NGOs) and multistakeholders.As well, environmental management of mining operations had to be realigned in order to meet these new realities and to respond to more elaborated regulations oriented towards sustainability. Environmental management systems (EMS) have been introduced not only to meet the assurance of conformance to regulations but also to prevent pollution and to apply the continuous improvement of mining processes. EMS models have been developed and certification to international standards (e.g. ISO 14 001) is a common practice.Globalization has imposed challenges and additional requirements to environmental management. Developing a mine in emerging countries implies dealing with international agencies, local communities, and a variety of government infrastructures to obtain a “license to operate.” This paper presents the structure of Cambior’s EMS and how it was adapted and implemented in the company’s operations in South America."

Jan 1, 2006

By D. B. Johnson

Acidic, metal-rich waters generated at working metal mines and abandoned mine sites are generally considered to be major pollutants of the environment. However, the metals they contain often have significant value of their own, or as sources of useful mineral products. We have developed novel bioreactor systems that facilitate the selective recovery of various transition metals (e.g. copper, zinc and iron) as defined minerals that can be recovered and recycled. The bioreactors use novel species of acidophilic bacteria. Ferrous iron is oxidised by Ferrovum myxofaciens, a specialist bacterium that forms large amounts of exopolymers and grows as filamentous streamers in flowing mine waters, and the ferric iron generated is precipitated as the mineral schwertmannite, a small proportion of which is used to remove any arsenic present in mine water. Copper and zinc are precipitated as sulphides using H2S generated by consortia of acidophilic and acid-tolerant sulphate-reducing bacteria in a continuous flow, on-line low pH bioreactor. Transition metal sulfides can be segregated by precipitating them, either on-line or off-line, at different pH values. The modular units that have been developed can be configured to treat mine waters of different chemistries. A hypothetical acidic (pH 2.5) mine water stream containing 500 mg/L iron, 100 mg/L of copper and zinc, 50 mg/L of aluminum and manganese, 2 mg/L of arsenate, and discharged at a rate of 10 L/s, is used as an example of the potential application of the mineral-generating bioreactors. The environmental benefits and economic implications of considering mine waters as resources rather than wastes are discussed.

Aug 1, 2013

By D. Sagara, V. G. Makhado

"A model based control strategy was implemented at Loulo Gold Mine in Mali, to stabilise the thickener underflow stream density. This stream acts as the feed to the leaching circuit. pH control of the leaching circuit was integrated with the model-based controller due to slow process dynamics that are not suited to PID control. The controller performance was quantified over a period of 6 months, and was compared to the performance before implementation. The model based controller reduced process variability for both thickener underflow density and pH considerably, and resulted in a reduction in flocculant and lime consumption of 9.32 and 6.55%, respectively. INTRODUCTION Reagent consumption in gold processing plants significantly contributes to the total operational costs. In a typical Carbon-in-pulp (CIP) circuit, the reagent consumption associated with leaching, adsorption, elution and regeneration contribute to approximately 15% of the total operational costs (Stange, 1999). At Loulo Gold Mine, the reagent consumption associated with leaching, adsorption, elution and regeneration contributes to 6% of the total operational costs. As such, a reduction in reagent consumption will present a significant opportunity for savings on operating expenditure. Variability in feed ore characteristics results in continuous changes in steady state operating regions, which presents process control challenges as a result of the long residence times in some of the process units associated with gold processing plants. Overdosing often occurs in the presence of process variability to ensure safe operation and to maintain recovery targets. As a means of reducing reagent consumption and accounting for significant changes in the feed to gold plants, some of the plants have resorted to improving their process control strategies around their circuits. This paper focuses on the implementation of a model predictive based controller at Loulo Gold Mine on their thickener and Carbon-in-leach (CIL) tank to: •,stabilise the thickener underflow density, and •,the CIL tank pH."

Jan 1, 2017

By J. A. Finch

Samples of feed and product from a closed grinding circuit treating a heterogeneous lead-zinc ore were taken. The feed was subjected to laboratory batch grinding in a rod and ball mill with the objective of simulating the closed-circuit size distribution. It was concluded that the batch rod mill can closely simulate this product if only the over-all size is considered, but mineral-by-mineral large differences occur. If, as is suspected, the mineral sizes are the important factor in flotation, the differences could lead to problems in interpreting flotation results. An example of mineral recovery as a function of size is described to illustrate the potential problems.

Jan 1, 1979

By M. Gagné, F. E. Goodwin

The mining industry represents a significant investment in infrastructure of which steel plays a key role. Many structures in a mine are made of steel including shaft structures (buntons, station steelwork and headgear); stope structures (roof supports, pipe hangers); haulageway structures (ore transfer stations, electrical stubbies); and surface structures (plant buildings, tank supports, pipe gantries, conveyor belts, stacks, stockpile structures, stairways and railings). Maintenance of structural components can often be difficult because of the environment, including those where corrosive fumes persist, or limited access, such as in shafts where access is limited, or to short maintenance shifts or where limited working space is available. Thus a cost-efficient, long-lasting and maintenance-free protection system for steel should be specified. Galvanizing provides the required high-quality, long-term corrosion protection to steel. Galvanizing provides protection in two ways, first as a physical barrier to corrosion and secondly by means of cathodic or sacrificial protection that is unique to zinc. The dual nature of corrosion protection provided by galvanizing significantly extends the service life of steel even in the most challenging environments. The unique corrosion protection properties provided by galvanized steel will be highlighted with global mining application case studies.

Jan 1, 2015

"Real-time, on-stream analysis of the metal content of process slurries is an essential prerequisite for process monitoring and advanced control of mineral processing circuits. On-stream X-Ray Fluorescence (XRF) sensors for base metal applications are available commercially and form the basis of many plant monitoring circuits. To date, these commercial technologies have been insufficiently sensitive to measure precious metals such as gold and platinum group elements, typically present at part-per-million (ppm) and sub ppm levels. CSIRO has developed a novel X-ray based technology, called UltraGold, which enables detection of gold in slurries on a real-time basis with a precision below 100 parts-per-billion. This technology is based on the use of advanced X-ray optics, extensive Monte Carlo computer modelling for analyser design, high accuracy X-ray spectrum fitting where the X-ray intensities are matrix corrected. In this paper, we will introduce this technology and discuss the results of a proof of principle study performed in the laboratory with plant slurries (tailings and concentrate) from an Australian beneficiation plant. Finally, we will discuss further planned improvements. As projected grades in (gold) mining around the world fall and several large-scale mines approach the limits of their economic reserves, this method can enable significantly reduced operating costs by rapid analysis to improve circuit efficiency and hence improve recovery significantly.INTRODUCTION This paper describes a study undertaken to explore the feasibility of applying CSIRO?s UltraGold XRF technology to the on-stream measurement of gold in process slurries. The provision of rapid, accurate information of gold grade in feed, tailings and concentrate streams would facilitate significantly improved process control and early detection of plant upsets, resulting in substantial cost-savings. CSIRO have patented X-ray fluorescence (XRF) techniques for the analysis of key elements in slurries present at part-per-million (ppm) and sub-ppm levels. Conventional, commercially available on-stream XRF instruments generally have detection limits in the tens of ppm range, precluding their use for analysis of elements like gold that are mined and processed at much lower concentrations."

Jan 1, 2017

By A. Plumtree

The morphology of environmentally assisted cracks in stressed pipeline steel has been investigated. For a dilute and neutral solution (NS4) simulating ground water in contact with the steel, semi-elliptical cracks grow faster on the surface (2c) than in the depth (a), hence, the aspect ratio (a/c) decreases. This is explained using a deterministic concept since corrosion is dominant and the primary constraint is the conservation of charge. By contrast, when mechanistic conditions prevail, significant growth occurs in the depth. When underloads are imposed in the loading history, temporary accelerations in crack growth occur because corrosion rather than mechanical effects become dominant.

Jan 1, 2005

By L. Fernandes

A two level factorial study was undertaken to investigate the relative impacts of factors affecting the kinetics of polytetrafluoroethylene, PTFE, assisted pressure oxidation of chalcopyrite. A copper flotation concentrate, principally composed of chalcopyrite, was leached in 850 mL of leach solution under conditions similar to those of the CESL process. The factors manipulated were: the amount of 1/8" PTFE beads added (100 g or 650 g), oxygen pressure (690 kPa or 1030 kPa), and concentrate addition (10 grams or 65 grams). Copper extraction data, which indicated complete leaching under certain conditions, were fit using a shrinking core model from which rate constants were estimated and further used to generate a statistical model containing only the factors of significance and their interactions. Results indicated a strong positive effect of PTFE addition and a strong negative effect of increasing pulp density. A weak negative interaction between increasing PTFE addition and pulp density was attributed to PTFE/concentrate agglomeration.

Jan 1, 2014

By C. J. Hall

This paper presents a basic motive column analysis of natural ventilation and shaft resistance, using the density depth diagram. The method makes use of tables showing the state of the air as determined by thermodynamic analysis. Several theoretical examples are given.

Jan 1, 1968

By Trent Hamilton

Cameco ? McArthur River Operation is a high-grade uranium mine in northern Saskatchewan. Average grades mined are nearly 20%, more than 20 times higher than other operating uranium mines in the world. The significant risks involved with mining this grade has been effectively mitigated using innovative and unique controls, implemented from development and production mining through to ore processing. The types and sources of radiation are presented and protection measures are discussed. McArthur River?s strong radiation culture is evidenced by continually low radiation exposures while transitioning to new mining zones.

Aug 1, 2010

By Osvaldo A. Bascur, Curt Heftier

The lack of integrated information including the Energy/Utility Suppliers with sufficient detail for analysis causes inefficient operation in metallurgical complexes including the Energy/Utility Suppliers . Defining the right context for information use is essential for sustainable operations. This being said, what are we doing to enable people to act upon information and to be aligned to optimize the use of resources like raw materials, energy, water and consumables for an entire metallurgical complex? Collaboration between all company entities is a key component of improving efficiency. Evolution of web technology and object modeling of enterprise assets enables collaboration across the whole business. Operational troubleshooting occurs more quickly as the organization acts on issues to reduce wasteful operation. This paper presents a real time software infrastructure with tools that give users the ability to sift through available data, transform data into information for business continuous improvement and optimization. We will introduce a new technology for analyzing real time data, information and events using multidimensional analysis of information to detect anomalies based on the statistics of the data classified by time events to reduce the information into action. A new paradigm for collaboration at a local and strategic level is proposed to enable the enterprise to become proactive in dealing with wasted time and products. Three examples from the industry will presented and their benefits highlighted.

Jan 1, 2011

By Pierre Labrecque

Dispatch systems have been used for open pit mining since the early 1980?s but similar systems do not widely exist for underground mining. There is a need for developing dispatch systems for underground mines, particularly highly automated operations such as block caving. An innovative method, Agent Based Modeling (ABM) for a dispatch system for a block caving operation, is proposed in this paper. The model is based on a particular behaviour observed in social insects. The focus of the ABM dispatch system is adaptability with respect to changing operational conditions and effective integration of maintenance modules with the operation. The paper will show the advantages of this innovative method compared to existing similar systems. Furthermore, the preliminary approaches for developing an agent based modeling system for block caving operations are highlighted and discussed in this paper. 1. Introduction In social

May 1, 2008