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By K. Sawada

Along with the expanding demand of copper concentrate in Asian countries, custom-smelters have confronted with difficulties of low TC/RC. Now, Japanese Copper Industry have 2 options; investment in mine development and/or recycling of copper scraps. The strategy of global mining companies is analyzed, and implications for Japanese Copper Industry will be discussed from the viewpoint of sustainability of smelters in Japan.

Jan 1, 2014

By C. Caballero, M. Rosales, C. León, A. Valencia, R. Fuentes, A. Moyano

Slopping is the formation of waves in the converter due to the gas injection by tuyeres. Those waves produce a premature wearing of the refractory lining of the reactor due to its great amplitude. The affected zones are the tuyere line (outlet gas from tuyeres) and the front of this line. In the present work, a theoretical and experimental study is made to develop a theory that determines the variables involved in slopping, characterizing the more important parameters of operation in the phenomenon of slopping. In addition, this theory will allow for determination of new technological alternatives of the blast injection permitting to depress the slopping phenomenon.

Jan 1, 2007

By P. J. Poirier, J. A. Meech, H. Raabe

"An Expert System has been implemented to assist operators in applying knowledge about froth conditions in the control of the flotation circuit at Highland Valley Copper. For some time, the personnel at Highland Valley Copper have recognized that froth type is a useful indicator of good operating conditions. However, the operating strategy based on froth type recognition is an ad-hoc skill in which different operators use a variety of terms, features and procedures to identify and solve problems. The first phase of this project developed an on-line consultative system to advise and tutor so that the diffuse expertise could be rationalized and consolidated into a standardized format.The second phase has brought this knowledge into a real-time environment to advise the operators on the floor in identifying froth types and troubleshooting corrective action. This paper describes the steps taken to acquire the knowledge, to design the required system features and to implement the real-time version of this system.INTRODUCTIONThe use of expert systems in the mineral industry has been gaining popularity in recent years. Minnova Inc, Les Mines Selbaie, Wabush Mines, Potash Corporation of Saskatchewan are just a few examples of Canadian mining companies that use expert systems to monitor or control their plants. Applications in the field of flotation include Brenda Mines (Edwards, 1992), Mt Isa Mines Ltd (Lacouture et al, 1991), Outokumpu (Karhu, 1989) and Kidd Creek (Burrows et al., 1989).Expert systems are defined as ""computer systems that apply reasoning methodologies on knowledge in a specific domain in order to render advice or recommendations much like a human expert"" (Turban, 1988). The main areas of application are diagnosis, training, process monitoring and control, and design. There are basically two main types of expert systems: Consultative systems, which are off-line applications in diagnosis and design, and on-line realtime systems, used for supervisory process control and real-time advising."

Jan 1, 1993

By Siavash Zamiran, Abdolreza Osouli

"One of the most concerns of room and pillar mining system is subsidence of the ground surface due to coal mining particularly in room and pillar mines. Subsidence of ground surface is a result of floor, pillar, or roof failure of the mine. At the same, due to many difficulties associated with surface disposal facilities of coal refuse, some mining companies are trying to use underground space as a disposal storage place. In this study, stability and subsidence analyses of an underground coal mine located in the Illinois Basin are conducted. This room and pillar mine was abandoned and later on was used as a storage place to accommodate the coal fine refuse with slurry backfilling method. The geological stratigrophy and geomechanical properties of the mine floor and roof were collected. Floor and pillar stability analyses were conducted for areas with various extraction ratios. The stability of the mine was evaluated both prior and after slurry backfilling. The floor and pillar stability analyses results of the mine due to moisture exposure after slurry backfilling are discussed. The subsidence potential due to mine failure is also evaluated.INTRODUCTIONA typical lithology of coal seams in the Illinois Basin consists of weak underclay stratum. The immediate weak underclay causes frequent floor instability problems in Illinois underground coal mines. There are two different stages in assessing floor stability of the mines where slurry backfilling is planned. The first stage is during the mining operation when weak underclay layer squeezes under pillar stress and results in punching or bearing capacity failure. The second stage is after slurry backfilling. During this stage, the slurry material soaks non-durable floor layers and causes strength reduction in floor material. Pillar stability conditions should also be taken into account during both the operational period and after the slurry backfilling."

Jan 1, 2015

By Virginia Lawson, Adam Price

The rougher flotation stage is used to reject liberated gangue at a coarse size. Base and precious metals due to their high specific gravity tend to recycle in the grinding circuit and report to the flotation circuit at a finer size than the gangue from which it is being separated. Generally liberation levels of greater than 50% are achieved in roughing and thus a portion of the feed can be immediately upgraded to final concentrate. The proportion increasing as the amount of liberated mineral in the feed increases. Scalping out concentrate from the rougher can reduce the size of the subsequent regrind and cleaner circuits. Examples of alternative process design for circuits demonstrates that you don’t need large volumes to effectively recover all of the minerals – you need smart flotation. Several case studies will be presented where circuits can be significantly reduced in size by designing smarter – not larger. This paper describes case studies to test the amenability of the Jameson Cell to produce final concentrate from rougher feed. Metallurgical performance and plant design implications are discussed. Froth flotation has been used extensively for mineral concentration for over 100 years. Although the flotation cell design has changed, it has generally simply increased in capacity rather than increase in efficiency. Cell capacities of over 600 m3 are now being used in rougher flotation particularly for the lower grade ores where the amount of surface area for flotation is deemed less significant than the required volume. The plant design volume in rougher flotation comes from laboratory batch flotation tests and/or pilot plants. The volume required for the plant is calculated based on the laboratory residence time multiplied by a scale- up factor. Examples of laboratory to plant scale-up design are given in Dunne et al. (2010 part 2). The factors are usually between 2 and 3. A laboratory residence time of 10 minutes would equate to a plant design residence time of 25 minutes using a 2.5 factor. The volume of the required flotation cells can then be calculated using the design tonnage and volumetric throughput. This scale-up factor takes into account the differences in performance between batch flotation efficiency and full scale plant. The differences are likely related to inefficiencies of bubble particle contact in large cells as well as froth recovery, which is essentially complete in a batch cell. Flotation cells, such as the Jameson Cells, are smarter designs that improve bubble/particle collection, bubble/pulp separation efficiency and operate with high froth recovery rather than simply getting bigger. The Jameson Cell was designed on the principal of improving the collection efficiency of fine particles by separating the contact zone from the separation zone and having the bubbles generated by the plunging jet shearing and entraining air. This means the method of bubble generation is not impacted by the wear of mechanical equipment as it the case in other flotation devices. Jameson Cells make bubbles less than 600 micron in size under most operating conditions (Ding, 2016).

Jan 1, 2019

By G. R. Baiden

This paper discusses the application of Load-Haul-Dump (LHD) machine teleoperation in combination with a guidance system for single operator control of multiple IJIDs. A system accomplishing these goals has been tested at Copper Cliff North Mine of Inco Limited. This development uses a high-speed, high-capacity production network to teleoperate an LHD during loading and dumping by using 3D video and radio remote control. Following loading, the operator dispatches the LHD using an automatic guidance system to traverse the drifts to the orepass. Remote dumping is done at the ore pass and then the machine returns to repeat the procedure. This has significant productivity gains and improvements in safety. Productivity is improved because operators are involved only in the loading and dumping part of the process. This frees the operators to utilize their time more effectively, loading or dumping a particular machine, while other machines with guidance systems continue to work travelling and/or automatically dumping ore in the ore passes. Safety is improved as the operator is located on a remote control station. Automatic dumping will be incorporated as a future development.

Jan 1, 1994

By I. S. Thompson

A program of geochemical till prospecting, carried out by Derry, Michener & Booth in 1974, was instrumental in t~ e discovery of a copper deposit in Currie Township, Ontario, beneath thick lacustrine deposits of the Abitibi Clay Belt. The prospecting system involved the continuous collection of glacial sands and gravels beneath the clays, using a track-mounted, dual-tube rotary drill, and the separation and geochemical analysis of the heavy mineral content for Cu, Zn, Pb, Ag and Au. In one of 22 holes drilled down-ice from nine Canadian Nickel airborne EM conductors, fragments of chalcopyrite-bearing graphitic argillite, assaying 12% Cu, were recovered from a 14-foot gravel section beneath 83 feet of clay. Ultimately, mineralization was identified in 10 of 11 additional holes drilled up to 3,000 feet down-ice from the Currie deposit. The glacial fan, when compared to the 1,200- by 165-ft area of the subcropping mineralization, is at least 20 times the area of the deposit and is the result of glacio-fluvial reworking of the mineralized ground moraine. The Currie deposit is contained within a Keewatin succession of graphitic argillite, dacite tuff and graywacke, which is intruded by dacite and feldspar porphyry sills and dykes and truncated by a Keweenawan diabase dyke. Grade and thickness of the mineralization, which lies chiefly within the argillite, is related to felsic intrusives and hydrothermal alteration, and to fold hinges.

Jan 1, 1979

By Ji Wang

Reflective in-seam wave detection has the advantages of a far detection range and wide applicability. It has been successfully used in detection of many abnormal geological structures in work-faces, such as faults and collapse columns. However, a reflective in-seam wave is a dispersion wave. It has weak energy and is always covered by the direct in-seam wave. In the past, underground seismic explorations were not able to image the opposite roadway using reflective in-seam waves. To solve this problem, we propose a new method of reflective in-seam wave imaging based on adaptive dispersion filtering. This method processes the reflective in-seam wave using a filter with the parameter of transmission distance. The degree of similarity of the filtered and the explosion signal is used to estimate the transmission distance and image the reflective objects. We test and verify this method using real underground seismic data. This research is helpful for the detection of coal mine goafs and abandoned roadways in work-faces or in front of tunneling ends.

Aug 1, 2013

By Ian Rozier

"Emphasis in recent years in western Canada has been placed on the development of large open-pit coal mines, the most notable developments being in northeast British Columbia. However, vast resources exist below the limit of economic open-pit mining, and with world demand predictions of the late seventies in mind, the potential of underground coal mining in western Canada has been investigated. Particular emphasis has been placed on the Plains coalfield of Alberta, and there is optimism that underground coal mines will be developed in the Lethbridge area of southern Alberta.With no existing operations in southern Alberta with which to compare mining conditions, any mine planning and feasibility level studies rely heavily on the engineering/geotechnical data obtained from surface investigation to predict ground control problems and technical constraints on mining. Such investigations have been integrated with exploration drilling programs. Emphasis has been placed on extracting maximum information to provide an over-all appreciation of potential ground conditions and to identify specific ground control problems that could be encountered.The acquired geotechnical parameters are then used to evaluate the mine properties from an engineering standpoint for input into the determination of optimum mine layouts, development directions, mining methods and roadway and face support requirements. These geotechnical studies have been primarily directed toward the longwall mining method, but the acquired data base could equally be applied to alternative mining methods.In addition to the lithologic and structural controls which relate to roof stability, caving characteristics, floor heave and subsidence, investigations have been directed at gaining an understanding of the over-all surface and ground water regime with respect to potential inflow into the mine openings and ground control problems that could be caused by inflows encountered during mining. Experience has shown that soft floor conditions and water control are important factors to be considered in a longwall layout, and without doubt these parameters will play a major role in the design and operation of a successful longwall operation in the Lethbridge coalfield."

Jan 1, 1986

By F. Doxey

Introduction In order to improve outputs and to reduce or hold mining costs, many attempts have been made to mechanize the getting and loading of coal in the major coal producing countries, and machines of various kinds and sizes have been designed and manufactured. Some of the most important are: Joy Continuous Miner Joy Coal Auger Goodman Mining Machine Lee-Norse Koal-Master Jeffrey Colmol Cardox Hordsecg Recovery Drill German Coal Plough British Coal Plough with agitated blades M. & C. Samson Stripper AB Meco-Moore Cutter Loader Joy Gloucester Getter The three last named are the chief longwall machines in use and the AB Meco-Moore and the Samson Stripper are doing a good job in their respective applications. It is understood that the Gloucester Getter recently installed in a British colliery also shows reasonable promise. It was felt, however, that to meet the conditions of the mines in Nova Scotia, any machine developed must have certain distinctive characteristics. It must: ( 1) Be able to cut and deliver coal in quantity and of the right sizes ( 2) Be easily manoeuvrable ( 3) Be suitable for longwall operations ( 4) Not interfere with timbers already set ( 5) Cut its own stable (6) Work on reasonably heavy gradients

Jan 1, 1951

By Terry J. Briggs, Ian J. Kelso

"Abstract- The Century mine in northwest Queensland,Australia, is a major sediment-hosted zinclead- silver orebody, located within the western Mount Isa Basin. Stratiform, carbonaceous shalehosted mineralization is developed within Proterozoic shale and siltstone sequences of the Lawn Hill Formation. CRA Exploration Pty Ltd (CRAE) discovered the Century deposit in 1990 and open pit mine development commenced in 1998 under the ownership of Pasminco Century Mine Limited (PCML). The deposit contains an identified mineral resource of 105 Mt @ 12.1% Zn + 1.7% Pb + 46 g/t Ag (Broadbent and Waltho, 1998) which is currently being mined at a rate of 5 Mt/y.In December 1998, an exothermic reaction was observed between explosives spilt onto shale drill cuttings from a blasthole. This reaction is referred to as ‘reactive ground’ and has the potential to cause premature detonation of explosives in a charged blasthole with catastrophic consequences. The incident led to a subsequent geological and geochemical assessment of the different rock types at the Century deposit and their potential reactivity with ammonium nitrate-based (AN) explosive products. This assessment was conducted in an attempt to characterize zones safe for blasting with uninhibited AN-based explosive products. A direct result of this study is a set of procedures outlining the use of different AN-based explosives in areas defined as potentially reactive or non-reactive for the different lithologies present. Black shales contained in both the waste and mineralized sequences contain the sulfide mineral pyrite (FeS2), which is thermodynamically unstable with AN contained in commonly used explosives. The potential reactivity of partially weathered pyrite can ultimately result in the decomposition of an AN-based explosive. It was determined that only pyritic black shales showed any potential to react with AN, irrespective of their position in the stratigraphic sequence. Other lithologies present at Century, including Proterozoic sandstone and Cambrian limestone, are classified as non-reactive with AN. This is a geological risk management situation present at the Century mine."

Jan 1, 2001

By W. Holyk

"Although lead, zinc, copper, and iron sulphides have been known for many years in the Bathurst region, the existence of large massive deposits was not known until the discovery of the Brunswick orebody in 1952. This was followed by the discoveries of the Anacon orebody in 1953 and the American Metals orebodies in 1954. There is no question as to the great importance of these large massive sulphide deposits, and no doubt that other sulphide deposits are to be found. The problem, of course, is where and how to find them.The discovery of the Brunswick and Anacon orebodies is attributed to geophysical work. The original discovery of the American Metals deposit is generally attributed to a regional airborne electromagnetic survey.It is generally stated that the Bathurst area is a geophysical camp, and this is essentially true, but in this highly competitive search for orebodies it is obviously impossible for an individual company to cover the entire area by a comprehensive geophysical survey. Some means other than geophysics must be used to narrow the target. The quickest, cheapest, and simplest method is geological investigations.It has been stated that nothing can be accomplished by geology in the Bathurst region, since the camp is largely covered with overburden. This is true only insofar as detailed work on certain properties is concerned. It is not true of the larger regional picture. Outcrops are scarce, but angular float is abundant, and precedent shows that angular float has moved but a short distance from its source.GeologyAeromagnetic maps published by the Department of Mines and Technical Surveys are the best guides to the geology and structure of the area. These maps supply factual information concerning the underlying rocks. When coupled with field investigations, they are very useful in the interpretation of regional geology and the selection of favourable areas. The discussion of the geology is accordingly centred upon the aeromagnetic maps. The following is essentially a working theory, based on geological facts as best reconciled with all other available information,"

Jan 1, 1949

By R. O. Grieve

"IntroductionCALEY (1945) and Evans (1950) pointed out that certain instances of convergence between Devonian and Silurian horizons, frequently evident in wells drilled for oil and gas in Ontario, appear to be related to local thinning of salt beds in the Salina formation and they suggested that leaching of the salt beds may have occurred. Exploratory drilling by Imperial Oil Limited since 1945 has brought to light several examples of structures similar to those discussed by Caley and Evans. The writer has had the opportunity to examine cuttings and data from wells which penetrated these structures and the attempt to interpret them in the light of the theory of leaching and subsidence proposed by Landes ( 1945a) to explain the marked brecciation and deformation of Upper Silurian and Middle Devonian sediments which crop out in the Mackinac Straits region of northern Michigan has led to the observations presented in this paper."

Jan 1, 1955

By G. O. Crowell

This paper gives the history of the celestite deposit, now being mined by Kaiser Celestite Mining Ltd., near Sydney, Nova Scotia. Mining and milling procedures are covered, and the regional and local geology of the area are described, including the origin of the celestite.

Jan 1, 1971

By Yusuke Yamamoto, Mineo Asano

"The present study investigated the texture transition during secondary recrystallization in the AA5182 sheet. During the initial stage of annealing, the texture showed a weak Cube orientation as the primary recrystallization texture. During the secondary recrystallization with abnormal grain growth, the area ratio of the {hkl} <011> orientations increased by consuming the other orientations. The texture transition was calculated by the 2-D Monte Carlo simulation with the misorientation dependency. When the higher grain boundary mobility was set in the specific range of the high angle misorientation, the orientation preferential growth of the RW {100} <011> orientation was reproduced. However, other {hkl} <110> orientations could not be well reproduced by the misorientation dependency.INTRODUCTION Crystal orientation and texture are important factors for aluminum sheet products from the standpoint of mechanical property, formability and isotropy. The recrystallization texture results from the orientation preferential growth from the rolling deformation microstructure and the texture (Alvi, Cheong, Suni, Weiland, & Rollett, 2008). Texture development has been a topic of intense research for decades with advances in analysis methods, e.g., orientation mapping (OIM) and computer simulations (Fjeldberg & Marthinsen, 2010; Ivasishin, Shevchenko, Vasiliev, & Semiatin, 2006). The grain boundary characteristic is considered to be a key for the orientation preferential growth. In the case of the recrystallization from the deformed microstructure, not only the grain boundary characteristic, but also the dislocation density and the subgrain size affect the nucleation and the grain growth (Engler, Löchte, & Hirsch, 2007). On the other hand, in the case of secondary recrystallization, the dislocation density and the subgrain size can be ignored and the effect of the grain boundary characteristic can play a significant role in the grain growth. There is intense research about the texture development during secondary recrystallization in aluminum alloys and it was reported that coarse {hkl} <011> grains were formed during the secondary recrystallization (Suk, Shin, & Huh, 2006; Rios, & Gottstein, 2001). However, the mechanism of forming the {hkl} <011> grains has not been fully clarified. In the present study, the effect of the grain boundary characteristic on the orientation preferential growth was investigated by EBSD analysis and Monte-Carlo (MC) simulation."

Jan 1, 2018

By D. Royston

Reducing SAG Mill feed size has been a major trend in recent years. ‘Mine to mill’ strategies have reduced blasted-rock size, and in a growing number of operations reducing the primary crusher CSS and/or adding additional crushing upstream of the SAG mill have reduced rock feed size. While reducing feed size will increase SAG mill throughput, issues arise in terms of retaining charge in the mill, exposing the shell lining to impact damage, and maintaining milling performance should the pre-crush system shut down. This paper reviews the past experience on pre-crushing for SAG mills and provides an analysis of liner design (in particular grates and shell liners) for pre-crushed feed.

Jan 1, 2012

By E. C. Keeley

THE property of Buffalo Ankerite Gold Mines, Limited, is in Delora township, Porcupine area, Ontario. The southwestern part of the property is ground formerly owned by Marbuan Gold Mines, Limited, which was acquired by Buffalo Ankerite in January, 1936. Until 1938, the Ankerite (or North) mine and the Marbuan (or South) mine continued as separate operations, each developed through a surface shaft and winze to the 1050 level and each having its own mill. This meant high hoisting costs, which, in 1936 and 1937, amounted to 36 cents per ton. In 1938, the underground workings of the two mines were connected on the 1050 level, and ore from both mines was hoisted at the main, or No. 2, shaft of the North mine, location of which is shown in Figure l. This shaft was discontinued at a depth of 1150 feet because, owing to the soft nature of the talc (serpentine) rock in which it was sunk, it had to be concreted throughout, and also because of its great distance--1,100 feet and 1,400 feet, respectively-from the North and South orebodies.

Jan 1, 1945

By Michael Fuller

Roadmap ? Examples of Partnership from UBC ?? Event Sponsorship ?? Recruitment & Connections ?? Opportunities ? National Recruitment Survey Results ? Conclusion with Key Points Event Sponsorship ? Annual Canadian Mining Games competition ?? 160 senior mining engineering students, from 10 universities ? Field Trips ?? 2nd year: Open pit ? Highland Valley Copper ?? 3rd year: Underground ? Myra Falls, Quinsam Coal ?? 4th year: Self-organized ? Chile, China, Poland, Brazil

May 1, 2008

From 1999 to 2008 rock related accidents accounted for 75 fatalities, nearly 6,000 injuries and almost 14,000 incidents (Pappas and Mark, 2011). Clearly this shows that rock related safety on coal mines remains a serious issue and more effort is needed to address this hazard. This paper reviews support design considerations and monitoring needed to improve rock related safety in room and pillar coal mines in the USA. From the present study design considerations continue to evolve and improvements in technology and a better understanding of failure mechanisms and methods to prevent these failures from occurring are in place. At first glance, the design of safe and efficient underground openings appears simple until the designer begins to realize the complexities and variability of geometries, geology, loading and stress influences, support designs and other factors such as corrosion and economics. Ultimately the goal of all designs is to ensure that it can be completed safely, last for the duration of the design life and it is economically feasible.

Aug 1, 2013

By Min-Sung Kang

Excavation and earthmoving equipment mostly operate in accident-prone areas. These areas normally have rollover, confinement, and fall or may be considered harmful work areas due to demolitions and sewage removals. It is inevitable that excavation and earthmoving systems should be developed to secure the safety of operators through unmanned and remote control systems. Therefore, this research proposes a system that enables excavators to be unmanned and remote controlled without any renovation, remodeling, change, or transformation by applying attachable and separable mechanism and modules. Moreover, this research proposes the sensor module to evaluate the dynamic status without processing remodeling or transformation the existing hydraulic drive excavation system by adopting the easy attachable and separable mechanism. The study verifies this proposal based on observed possibility and feasibility through the experiments.

Aug 1, 2013