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By M. Kalin

"Ecological Engineering, a biotechnological approach to the decommissioning of base metal mining wastes, is being tested on two pits (Gloryholes) in Newfoundland, Canada. Pit #2 has an average pH of 3.5 and flows into Pit #1 where, through additional ground water contribution, the pH is circumneutral, ranging between 5.5 to 7.The AMD in Pit #2 originates from underground workings and exposed massive sulphide on the pit walls. The overflow from Pit #1 averages about 10 L/s with less than 0.2 mg/L of Cu and 40 mg/L of Zn.Ecological Engineering utilizes organic substrate as a source of carbon and nutrients for microbial populations which can generate alkalinity and reduce metals. In 1989, limnocorrals (enclosures of 4 m diameter and approx 3 m depth) were placed in both pits to test the most suitable organic amendment (peat and sawdust). Microbial alkalinitygeneration was evident 95 days after placement of the amendment on July 4, 1989. The pH had increased after 120 days from 3.5 to 4.5 and by day 480 the pH was 7 in limnocorrals in Pit #2. Zinc concentrations in the limnocorrals in Pit #2, dropped from an average of 35 mg/L to about 2 mg/L or less, by day 480.A scaled-up experiment has been under way since August 25, 1990, where 390 m3 are treated in pit #2 and 750 m3 in Pit #1. One hundred eighty days after placement of the amendment, zinc was reduced in the acid Pit #2 from 40 mg/L to 15 mg/L. Research is underway to determine those factors which limit microbial activity."

Jan 1, 1992

By C. George Miller

"As the influence of governments has become more widely felt, the use of research techniques to analyze policy has increased. Mineral economics, as one of the foundations of mineral policy research, has grown accordingly. Policy research and analysis has been carried out within governments, university departments and the private sector. Each of these institutional environments has characteristics which influence the topics of study, the approach, the methodology and the output of the research. A brief survey of recent research activities provides illustrations of trends and developments occurring within this organizational framework.A radically different organization, the independent research institute, has begun to make an impact on policy research in recent years, and will have an increasing importance in the future. Combining certain features of the traditional research organizations, it nevertheless has important differences which are essential to its effective functioning. An overview of the formation, goals, organization and operation of one such institute is presented."

Jan 1, 1976

By D. C. Peck, H. D. M. Cameron, N. M. Halden, L. S. Jobin-Bevans

Abstract-The late Archean Pipestone Lake anorthosite complex (PLAC) is a 0.9 x 17 km sill-like layered intrusion that is part of a suite of coeval megacrystic anorthosite bodies in the Cross Lake region, northwestern Superior Province. Exploration for Ti-V-Fe oxide mineralization and concurrent geological investigations have contributed to a greater understanding of the lithostratigraphy of the PLAC and its oxide mineralization. Mapping and drill core studies have established a laterally continuous igneous stratigraphy comprising six leucogabbro/anorthosite zones and three melagabbro/gabbro zones. Field evidence, including disrupted blocks of layered units, scour contacts, and size-graded and modally-graded layering, suggests younging towards both the northern and the central parts of the complex. A decrease in the anorthite content of the feldspars from An75 in the south to An30 in the north suggests that the magmas become more evolved to the north. Macrorhythmic layering and gross morphological features suggest that the PLAC crystallized from four major influxes of geochemically similar basaltic magmas. The paucity of magmatic erosional features in the PLAC indicates that layering developed in a relatively static magma chamber, so that in-situ crystallization processes are required to account for the observed petrologic diversity. Drilling has confirmed that a significant Ti- V-Fe resource is contained in two of the four discrete mineralized subzones in the PLAC. Textural evidence and the stratiform nature of the oxide-enriched subzones are consistent with a magmatic origin for the oxide mineralization.

Jan 1, 1997

By R. A. Bergman

"Process descriptions are provided for the following ten plants that treat high-magnesia lateritic nickel ores (saprolite) by pyrometallurgical means: PT Aneka Tambang; Cerro Matoso S.A.; Falconbridge Dominicana C. por A.; Hyuga Smelting Company Ltd.; Larco (Societé Minière & Métallurgique de Larymna); Loma de Niquel; Le Nickel, SLN-Eramet; Nippon Yakin Kogyo Company Ltd.; Pacific Metals Company Ltd.; and PT Inco Indonesia.Flowsheets, equipment information,chemistry and production data have been compiledfor plants based on both information providedby the companies and on calculated massand energy balances.IntroductionNickel is of vital importance to modern society. Without it, we would not be able to enjoy many of the things that we take for granted, such as computers, airplanes and stainless steel appliances in our homes and workplaces, to mention a few.Nickel occurs in nature both as sulphide and oxide ores. Approximately 36% of the nickel reserves in the Western World occur as sulphide and 64% as oxide ores. Sulphide ores respond to concentration processes, whereas, oxide ores do not. Sulphide ores mined at 1% nickel can be readily concentrated to 10% nickel, whereas, oxide ores cannot be concentrated and therefore have to be processed as mined.Laterite ores are normally classified intotwo groups:1. The high-magnesia ores, saprolites or serpentines, are, as a rule, processed by smelting. The main reason for this is that the nickel replaces magnesium in the magnesium-silicate lattice. To be able to recover nickel, the lattice has to be destroyed. This can be achieved by smelting under reducing conditions.Acid leaching is also possible, but in this case, large amounts of MgSO4 or MgCl2 will be produced making it costly to regenerate the acid.2. The high-iron, low-magnesia ores are known as limonite. The nickel is relatively loosely bonded to goethite and hence can be recovered by selective reduction followed by ammonium-ammonium carbonate leaching. In recently developed processes, these ores are also being extracted by acid pressure leaching, with high Ni and Co recoveries.This paper focusses on the production of ferronickel and nickel matte from the highmagnesia ores."

Jan 1, 2003

"In an environment of rising energy prices and mining at greater depths, cost-efficient loading and hauling equipment is essential. Conducted at an underground mining operation, this study analyzes the energy consumption and gas emissions of diesel and electric load-haul-dump machines (LHDs) with similar bucket capacities. Based on energy prices from the first quarter of 2014, results of discrete event simulation show that energy costs for diesel and electric LHDs are US$0.24/t and US$0.07/t, respectively. Also, diesel LHDs emit 2.68 kg CO2 per litre of diesel fuel, whereas using electric machines reduces the need for ventilation to mitigate engine heat and emissions and reduces energy costs.RÉSUMÉ Dans un contexte de croissance des prix de l’énergie et d’exploitation minière à des profondeurs de plus en plus grandes, il est essentiel d’avoir des équipements de chargement et de transport les plus rentables possible. La présente étude, effectuée dans une mine souterraine, analyse la consommation énergétique et les émissions de gaz de chargeuses-navettes (LHD) au diésel et à l’électricité ayant des capacités de godet similaires. En se basant sur les prix courants de l’énergie, les résultats d’une simulation d’événements discrets montrent que les coûts énergétiques pour les LHD au diésel et à l’électricité sont respectivement de 0,24 $US/t et de 0,07 $US/t. De plus, les LHD au diésel émettent 2,68 kg CO2 par litre de combustible diésel alors que les machines utilisant l’électricité réduisent le besoin de ventilation pour atténuer la chaleur des moteurs et les émissions en plus de réduire les coûts énergétiques."

Jan 1, 2015

By V. I. Lakshmanan, D. A. Mackie

"1. INTRODUCTIONIn the past two decades, low-grade gold and silver ore bodies in the United States have been exploited by heap leaching, primarily with sodium cyanide solutions. This method has proven to be a viable alternative to conventional milling due to its low capital and operating costs. Successes have been made, particularly in Nevada, where ores are well oxidized and the climate is conducive to this method. in recent years, heap leaching has been tried in northern latitudes with some success, however, in using this method, operators face more severe limitations than do their neighbours to the south.This paper evaluates the limitations of heap leaching with particular emphasis on northern climates and introduces an alternative method to recover precious metal values in a continuous vat. This proprietory technology, known as the Mackie Vat Leaching Jig, shows promise, with improved gold recovery and potential to operate in cold climates.2. WHAT ARE THE LIMITATIONS TO HEAP LEACHING?Heap leaching of non-refractory ores is subject to the following limitations:1. Minimum amount of free gold and nuggets in the ore.?. Minerology of the ore--accessibility of gold to lixiviant.3. Minimum particle size and size distribution of crushed product to allow percolation of lixiviant through the heap.4. Minimum amount of clays or clay-like slimes that can cause coating of ore particles and channelling of lixiviant.5. Minimum strength of ore particles or agglomerations to allow economic height of heaps to be built.6. Amount and suitability of real estate.7. Amount and type of precipitation.8. Ambient temperatures.9. Possible poorer lixiviant diffusion.10. Possible lower oxygen content in dissolved cyanide solution with higher heaps, particularly with ice and snow cover."

Jan 1, 1989

By W. T. Martson

ABSTRACT Sooner or later, every producing mine faces the question of fill. This paper invites consideration of mill tailings as an economical, efficient, and quantitatively adequate source of such fill. Some of the advantages, disadvantages, methods of utilization, and methods of treating mill tailings for sand recovery are covered. ADVANTAGES AND DISADVANTAGES OF SAND FILL DISREGARDING economic com-promise, that material which supports the greatest applied load with the least compression is the best choice for fill. Table I, reproduced from U. S. Bureau of Mines Bulletin 60, is offered as evidence of the adequacy of hydraulically placed sand. Table II gives the results of tests made in an effort to determine the reason for the difference between load hearing qualities of dry-placed and hydraulically-placed sand. From these, it would appear that hydraulic placing gives a denser initial packing, with corresponding higher, and faster development of, load bearing qualities. Assuming this to be true, then if sand from mill tailings can be placed underground economically, it is the superior fill material. Table III summarizes cost data available. The most cursory glance through the available references (2, 5, 6, 7, 8, 9) will show .that the major benefit from the adoption of sand fill is a decrease in the non-productive fill ?cycle of a working place. This, it is estimated, increases the output of an individual stope by from 25 to 50 per cent. The advantage of reducing the number of required working places for a constant daily production is obvious.

Jan 1, 1951

By G. C. McKerrow

"Mr. G.C. McKerrow, Assistant Manager of Noranda Mines and formerly Smelter Superintendent attended the meeting to answer questions as to why smelters imposed penalties for too much zinc in a copper concentrate or too much copper in a zinc concentrate, etc.D.W. Bridges -Mattagami Lake MinesWhat limits do you set on zinc and lead in a copper concentrate?G.C. McKerrow - At Noranda, we allow 5% zinc free and charge 25 cents for every unit above that. For lead, it is 1% free and 25 cents per unit above that. Lead is a much more harmful impurity than zinc because it tends to recycle more in the smelter circuit and creates a greater health hazard in the plant.E. Thornton - Sullivan GroupWHat harm does fluorine do in the smelting process?G.C. McKerrow - Fluorine usually does not occur in harmful concentrations in non-ferrous smelters. Fluorides are present in exhaust gases in the aluminum and phosphate industries. If these fumes escape into the atmosphere, they may settle out on forage grasses in concentrations that are harmful to livestock.Thorton - Sullivan GroupI have asked this question other places and have been told that it is hard on brick linings and causes gold and silver to be lost up the stack.G.C. McKerrow - Almost any volatile constituent in a smelter charge will aid in carrying other metal values. To this extent it may be harmful.E. Thornton - Sullivan GroupMr. Tait mentioned before a smelter where they have a copper-tin ore and they pay for copper, tin, bismuth and silver but object strongly to indium in the concentrate. Why would this be?G.G. McKerrow - 1 can't see why indium would be a serious impurity. It does tend to concentrate in flu dusts and if you get enough of it you can recover it and sell it but I have never heard of anyone putting a penalty on it.Question - I once ran into a small copper mine in Peru that had cadmium in the copper concentrate but no zinc. The copper smelter charged a penalty for the cadmium. Why would this be?"

Jan 1, 1971

By C. S. Maggs, L. Shwydiuk, H. W. Newcomen

The southwest wall of the Lornex Pit at the Highland Valley Copper mine has been experiencing slope displacements since 1978. Measures to manage the displacements on previous pushbacks have included stepping out, scheduling pushbacks to unload the crest of unstable areas, slope dewatering and mining with intensive slope monitoring. The final pushback on this wall is currently being mined and substantial modifications to the slope geometry could prove to be uneconomical. As a result, a campaign of surface water collection and diversion, horizontal drainhole drilling and deep well drilling is currently underway to maintain an acceptable degree of stability to the end of mine life. The various factors contributing to instability, including engineering geologic controls, rock mass strength, and surface and groundwater hydrology are presented. Movement trends, displacement magnitudes and stability analyses results are also discussed.

Jan 1, 2003

By A. Dreimans

Tracing of 'float' against the latest ice-flow directions ha!' led to or assisted in discoveries of several mineral deposits in Canada at lP.ast since 1891, e.g., fluorite and corundum in eastern ?Ontario, Steeprock and Josephine iron ore in western Ontario, Malartic, Fisher-Quebec, and Lamaque gold ore, and Vendome zinc ore, in western Quebec, Sullivan zinc and lead sulphides in British Columbia, Orvan Brook or New Calumet sulphide deposit in New Brunswick, Lynn Lake nickel sulphide de-posit in Manitoba, etc. Pebbles or ore boulders whose source has not yet been found include diamonds in the Great Lakes region and ?sulphides in several localities in Ontario and Quebec. Complexity of transport of ore boulders, including non-glacial transport, may be the explanation. Tracing of ore boulders requires knowledge of the Pleistocene history of each particular area (ice flow directions, their ?changes during glacial oscillations, existence of pre-glacial lakes with ice-rafted boulders, later interference by streams, lakes, mass movements). Important also is distinction of till from similar non-glacial deposits and knowledge of the bed-rock geology. Quantitative methods, e.g., pebble counts, maybe applied while tracing magnetite, hematite, or goethite. Fragments of sulphide ores are less abundant in indicator trains, and quantitative methods are less suit-able for tracing them. Heavy-miner-al investigations may give good results for minerals resistant to weathering. Geochemical methods are of value only in the vicinity of ore deposits.

Jan 1, 1958

By E. W. Johnson

"The title of my paper is ""I 'Wonder Where The Yellow Went"". As you can readily guess, it is not related to an old-fashioned ""Pepsodent"" sales pitch! Rather, it concerns a situation which arises all too frequently in some gold milling operations, namely when actual ounces of gold production do not come up to estimated or projected ounces. The boss man scratches his head and wonders where the missing gold has gone and how it has disappeared. The problem, if one exists, is amplified if one forgets that an estimate is just that - an estimate - and not a hard fact - even though the numbers are produced by computers. And yet, from the point of view of engineering; financial and production planning and security; it is most desirable to tie together all data relating to production estimates, losses and actual production.In the course of this paper reference will be made to the term ""variance psychology"", to a few of the physical properties of gold and to the nature of its occurrence in Canadian ores, in relation to the topic under consideration. Activities which have a bearing on production estimates will be reviewed. These include: weighing, sampling, assaying, estimating residual losses and, in cyanide plants, gold precipitate production. Mention will be made of apparent, unaccounted for and unknown losses. In conclusion, I shall draw from personal experience and relate three examples of ""Where the Yellow Went''."

Jan 1, 1986

By T. Skinner, M. Sahebkar

"In recent years, the mining industry has been inundated with new technologies and software systems to aid in productivity improvement. Accompanying this increased level of technology and computer systems has been the exponential growth in data sources and sinks for all aspects of a mining operation. This rapid growth in data and technology has evolved through vendor “push” approaches and user “pull” scenarios, the result of which has been that currently, no standards exist defining how data from new technology should be accessed and transferred from surface mining equipment and systems. Consequently, many incremental benefits of the systems have not been realized. This paper will present a discussion of this important issue and introduce a new committee formed to address standards to assist the industry in making effective use of current and future technology. Potential benefits accruing from the development of these standards will be illustrated through the use of a case study at Fording Coal Limited. IntroductionThe mining industry is currently faced with a rapid evolution in the computing-based systems capabilities of mobile production equipment. At the same time, there is a trend toward the introduction of even larger machines, with novel designs or incorporation of new technologies within existing designs. Computing and control technology will be required to operate and acquire knowledge about equipment operation, utilization, and performance. Such knowledge has the potential to lead to enhanced equipment design, more appropriate equipment selection, and optimized equipment performance. The equipment systems will be required to be integrated with mine production monitoring systems, maintenance management software, and a wealth of other information systems to provide a complete understanding of the effects of various factors such as maintenance, equipment design and production on economics (Roman and Daneshmend, 2001). This will lead to a better understanding and implementation of the opportunities to enhance the performance of the mine through interaction of the mine operations."

Jan 1, 2003

By H. M. Lewis

The current status of the international zinc market is summarized, and a supply /demand outlook is presented for the next five years. A number of technical problems facing the industry are outlined. Introduction ZINC has sometimes been called the unknown metal. Considering that on a world basis it ranks third among non-ferrous metals in production and consumption, zinc retains a certain modesty. It has no distinctive colour like copper, lacks the low density of aluminum or magnesium and is not always easy to identify as a product. The 'spangle' of galvanized steel is probably zinc's most distinguishing feature. The purpose of this article is to develop an over-all review of zinc. Starting with the current position of the metal, the major factors that will shape its future will be described so that an assessment of the outlook for zinc can be made.

Jan 1, 1978

By Jacek Paraszczak

For mining companies facing strong international competition and unfavorable commodities? prices, automation of underground operations has got a potential to increase productivity and help cut cost. However, despite considerable technological progress in this field, there still remain some problems to overcome. Furthermore, a success implementation of automation depends also on numerous operational, organizational and even human factors. In this context, this paper reviews briefly a technological progress with regard to different underground operations. Following that, several issues related to implementation of automated equipment and systems are presented and discussed. Particular emphasis is put on the factors whose importance is sometimes underestimated. Some recommendations in this respect are also given. It is stated that a success of an automation project is a function of many ?winning conditions?, which may be created through a very thorough planning and preparation. It is also underlined that despite achievements made, a vision of a man-less underground mine is not yet a question of near future as it may seem.

May 1, 2001

By T. Salman

Most authorities agree that the dissolution of gold from an ore takes place according to the Elsner equation first stated in 1846. The main requirements for the dissolution reaction to proceed are:(1) that the gold be clean.(2) that the gold be exposed to the solution.(3) that the cyanide solution be active, i.e., not over loaded with impurities which could retard or inhibit the reaction.(4) that an adequate supply of oxygen be available (from air).When the above conditions are met, cyanidation becomes basically a mechanical operation.Minerals such as quartz, calcium carbonate are relatively inert to cyanide though they may give rise to mechanical troubles. Most ores present an assortment of chemical problems, depending upon the constituent present, which react to the solution to varying degrees. It should be borne in mind that minerals which are disturbing to the operation, though present in small amounts, usually exceed the weight of the gold by several hundred times. In addition, the application of flotation and other forms of concentration to gold ores, previous to cyanidation, concentrates not only the gold, but also the other heavy minerals and these complicate the chemistry of the process.

Jan 1, 1975

By Corrie Pitzer

Safety performance in many companies and even industries has stalled in the few years. Accidents rates are at a ?plateau? and yet, serious accidents and fatality rates are not. In more dramatic cases, such as in the BP Texas disaster, organizations that have ?exemplary? safety statistics, suddenly have a catastrophic or multi-fatality event occurring. Other classic examples are the Piper Alpha disaster and NASA?s Challenger and Columbia disasters and even the Chernobyl nuclear reactor. Looking into the root causes of these accidents provides an insight into the events and deficiencies that led up to the accident, but what are the common features in the organization?s mindset? What characterizes these organizations? decision making, their approach to safety and to risk and are there specific cultural features that can be delineated? The research and review presented in this paper covers a period since 1994, which started in the Australian resource industry and since then covered international events. The features of these organizations are summarized as the seven deadly delusions, based on extensive research since 1997 of organizations that suffered unexpected disasters. Their huge focus on safety, the achievement of lofty goals and celebration of safety successes led to ?mindset? that they are leaders in safety, protected by an extraordinary safety system and that their safety incident figures indicated a truly world-class safety performance. It led them into the trap of the seven deadly delusions?

May 1, 2011

By Tao Long

Recently, the great amount of funds has been invested in the reconstruction of damaged infrastructure and house of subsidence area of coal mine and mine reclamation. This is a benevolent and popular work, which is highly praised. However, because of complicated collapse area problems in China, especially the less integrated control research in the collapse area of metal mine, and the technological weakness, how to effectively control the subsidence area, restore landscape and ecological environment, and utilize the abandoned mine land, are major issue related to the mining area of sustainable development. The research situation about the formation of metal mine collapse area at home and abroad is reviewed, and then the effect of the collapse area on the mine safety and ecological environment, the existing technical problems and development direction are analyzed. Lastly, the technical measures of the collapse area control and cooperative underground mining is put forward.

Oct 1, 2010

By R. S. Fukuhara, M. J. Allan

"Highmont, a wholly owned subsidiary of Teck Corporation, operates a 25,000 ton/day mine and concentrator located in the Highland Valley of British Columbia. Construction of the plant commenced in the spring of 1979, and production from one grinding line began in late December 1980. The second grinding line began production in March 1980.The ore body consists of two main zones, the east and west pits, containing 134 million tons of ore, averaging 0.26% Cu and 0.27% Mo. Mineralization consists mainly of chalcopyrite (2/3), bornite (1/3), and molybdenite.The concentrator design incorporates an A-B-C grinding circuit (auto mill ball mill - crusher), followed by bulk flotation, copper-moly separation and leaching for moly concentrates. The two grinding and bulk flotation circuits are parallel and independent. Concentrate storage is provided between bulk flotation and copper¬moly separation and also ahead of molybdenite leaching. The plant design has been previously described in some detail. (""THE HIGHMONT CONCENTRATOR"" by C. V. Sibbald, CIMM Bulletin, March 1981).This paper will outline some of the problems associated with the construction, startup and early operation phases of the concentrator. The objective is to help others avoid some of the potential pitfalls by outlining those areas where problems occurred, or where things went well. Criticism of design or equipment is not intended."

Jan 1, 1982

By C. D. Shackelford, J. F. Muñoz, M. Vauclin, P. Rengifo, A. Suazo

The results of a field-scale study involving in situ leaching of copper ore tailings using sulphuric acid as the leaching agent, injection wells to introduce the leaching solution and extraction wells to recover the copper-enriched pregnant leaching solution are presented. The study was performed at an abandoned tailings disposal site using a battery of injection and extraction wells. The medium was characterized through the determinations of physical, chemical, mineralogical, and hydro-dispersive properties based on laboratory and field tests, including a tritium tracer test, a pumping test, particle size analyses, and hydraulic conductivity tests. Numerous horizontal strata with different hydraulic conductivities were identified. A previously developed model was used to simulate the leaching of copper ore tailings. Although the study confirms the feasibility of using in situ leaching for recovery of residual copper from tailings deposits, the efficiency of the technology depends significantly on the medium stratigraphy and hydraulic conductivity.

Jan 1, 2001

By Ralf M. Kleine

THE property of Consolidated 1 Discovery Yellowknife Mines Limited, (Figure I) is situated in the Northwest Territories, approximately 50 air miles north of the town of Yellowknife. The mine is reached by a shaft which extends from surface to a depth of 4,000 feet, with working levels established at 1 50-foot intervals. Stopping operations are carried on throughout a vertical range of 2,000 feet, with both shrinkage and cut and fill methods being used, depending on the ground conditions. Production started in 1950 and milling is done in a 1 65-ton per day cyanide plant. During ten months of the year, the property is serviced entirely by air, utilizing charter aircraft from Yellowknife. A 4,000-foot runway near the mine was constructed from mill tailings. This strip is adequate to receive Bristol freighter planes carrying heavy loads. Other servicing is done by Otter aircraft, equipped with skis or wheels for winter and with pontoons for summer operations.

Jan 1, 1962