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By Brooke Clements

The Buffalo Head Hills region is located approximately 350 kilometres northwest of the city of Edmonton in northcentral Alberta (Figure 1). The Alberta diamond joint venture consisting of Ashton Mining of Canada Inc., Alberta Energy Company Ltd and Pure Gold Minerals Inc. began exploring for kimberlites in the Buffalo Head Hills region in late 1996. At the time, the Mountain Lake diatreme, located 200 kilometres to the southwest, was the only reported kimberlitic rock in Alberta (Leckie et al., 1997, Figure 1). Exploration efforts since 1996 have successfully identified a new diamondiferous kimberlite province in Canada.

May 1, 2001

By C. Mawdsley

The Tata Steel mill at Skinningrove in the North East of England produces top hat sections for mineshaft guides in sizes 102 and 150 mm. The top hat section is the technically preferred shaft guide choice for modern deep mine shafts. This paper explores the relative service performance of top hat and square hollow section guides in service. Comparative corrosion performance is reviewed and the paper describes work commissioned by Tata Steel (as Corus) undertaken by Aker Kvaerner Engineering to evaluate relative winding speeds, relative loads and fatigue life in service. The experience of supply to UK Potash mining is discussed and the future view of high capacity hoisting and larger section size market need and availability is assessed.

Aug 1, 2013

By B. Hewitt

Murrin Murrin Operations has not had a successful beginning. Numerous reliability and operability issues many of which are the result of design decisions have been addressed through mechanical and operational changes and the CCD circuit is no exception. The decision to install, the installation and the results of the CCD1 rake-lift mechanism and feedw ell dilution system are discussed in this paper. The installation was justified on improved operational robustness and an increase in the in the underflow density of 1% (per cent w/w). At approximately the same time process modifications in the solution neutralisation circuit were implemented and these changes altered the rheology of the slurry reporting to CCD1. Since the modifications to CCD1 and the solution neutralisation circuit, the CCD circuit has averaged a 2% improvement in the circuit underflow density. The CCD1 modification was completed on time and mechanically has performed well. From a risk point of view, the central rake-lift and Turbodil® dilution system add a degree of freedom and robustness to CCD1 operation that has extended the range of operational confidence. In this respect, the modification has been a success and is complementary to solution neutralisation improvements.

Jan 1, 2004

By M. Hamamoto, M. Furuta, S. Tanaka

The Tamano smelter and refinery has expanded its production from 228kt/y to 260kt/y since 2006. It was not a big jump, but efficient and economical improvements were executed. These were not only de-bottlenecking and modernization of the smelting plant, including the acid plant, but also additional processes were commissioned, e.g. slag cleaning furnace and steam dryer. On the other hand, a conversion to permanent cathode process in the #2 tank house made the biggest impact on production efficiency for the refinery plant. In order to overcome the drastic change of copper business, although each scale is not so big, continuous improvements are very important to survive. This paper mainly describes the recent improvements of the smelting plant.

Jan 1, 2007

By O. E. Humeniuk, A. I. A. Salama, M. W. Mikhail

"Performance testing of prepartion plants is referred to as plant audit. It evaluates plant performance under normal operating conditions and is aimed at improving yield through knowledge of actual process performance and interactions between different processes in a plant.This paper describes the program to evaluate the performance of several Canadian preparation plants. The performance test requires the planning of a sampling campaign that would include all circuits in the plant. Samples are analyzed to determine washing characteristics (screen and float-sink), ash and per cent solids of feed and products of separation units in the plant. Performance characteristics are established based on analysis and material balance. Specific recommendations can then be made to improve recovery, and identify and explain potential causes of apparent deficiencies.The objectives of the program are to reduce the cost of production by improving recovery of clean coal and, in tum, to reduce disposed tailings, establish baseline information on coal preparation plants performance in Canada, and define R&D work needed to optimize plant operation."

Jan 1, 1993

By B. Haneman, J. A. Gorst, W. Slabbert

"The Bayer process involves the digestion of bauxite in caustic liquors at high temperature and pressure. Typically the digestion section of the plant involves the heating of liquors up to the digestion temperature followed by flashing of the digestion product to atmospheric pressure with the flashed steam used to pre-heat the incoming cold slurry. Despite the heat recovery, the digestion process is a high consumer of energy. The application of tube digestion technology in such plants has resulted in significant improvements in refinery energy efficiency with associated benefits of process simplification and refinery flow sheet capital cost reduction. This paper reviews the potential application of this technology to other metals within the non-ferrous industry.THE BAYER PROCESSA typical Bayer flow sheet is shown in Figure 1. The raw feed material bauxite (containing aluminium hydroxide as gibbsite Al(OH)3 and boehmite AlO(OH)) is digested in caustic liquors (caustic soda is the solvent) at high temperature and pressure. This process extracts the alumina and silica and any carbon present on the ore. The slurry is then flashed down to atmospheric condition allowing for heat recovery from the flashed vapour and producing slurry supersaturated in alumina.Following the digestion process the mud is removed via thickening and then pressure filtration to remove fine particulate and produce a clarified liquor with dissolved alumina in solution. The resulting pregnant liquor is then cooled allowing the alumina in solution to precipitate as aluminium trihydrate Al(OH)3. The precipitated hydrate is then filtered and washed and classified into fine and coarse fractions. The fine material is returned to the precipitation process as seed while the coarse fraction is calcined at high temperature to produce alumina. The filtrate from the filtration process (spent liquor) is then heated by the incoming pregnant liquor before being fed to an evaporation process which produced the strong caustic liquor required in the digestion process. Finally, the mud from the thickening process is washed to recover caustic and then fed to tailings ponds. The washer overflow is then mixed with the digester product to increase super-saturation."

Jan 1, 2012

By W. F. J. Cosser

AN agreement having been arrived at in 1935 whereby McIntyre Porcupine Mines would purchase gravel for back-filling purposes from Hollinger Consolidated Gold Mines, the aerial gear as described below was installed. As originally discussed, the plan called for installation of a loading bin at the junction to the Hollinger tram, so making the McIntyre tram an entirely separate unit. The experience of the Hollinger engineers, however, went to prove that the operation of a bin (remote from sources of heat) should be avoided if possible, owing to the severe winter conditions (35° to 40° F. below zero).

Jan 1, 1938

By H. A. Pearse

Introduction This paper may be regarded as another instalment of the story of the Britannia milling operation. From time to time in the past, articles (1) have been prepared by various members of the staff, giving details of crushing, grinding, and flotation treatment for the normal Britannia ore. It is not, therefore, the purpose of the present paper further to discuss what may be termed the standard milling operation, but rather to describe a flotation practice which has been evolved directly as a result of the general depression. The normal Britannia ore mixture contains chalcopyrite and pyrite as the main sulphide minerals, together with minor gold and silver values. The standard milling practice, evolved during several years of experimentation, provided for bulk flotation of the two sulphides after primary grinding to only approximately 35-mesh, followed by regrinding of the bulk concentrate, with subsequent separation of the chalcopyrite and pyrite to make a marketable concentrate of each mineral. However, in the face of a constantly increasing surplus of copper on the world markets and a steadily falling price during 1930 and 1931, it was obviously undesirable to continue producing large quantities of this metal at a loss. On the other hand, Company officials were very reluctant to add to unemployment by closing down entirely, provided operations could be continued without excessive losses. Fortunately, the existence was known of a fair sized body of ore, quite low in copper and relatively high in zinc content, with also a very considerably higher gold value than that prevailing in other sections of the mine.

Jan 1, 1934

By S. C. Radopoulou

Pavement condition assessment is an indispensable constituent in maintaining roadway infrastructure. Current practices for pavement condition assessment are labor intensive which introduce subjectivity in pavement rating and are time consuming. Automated methods rely on full 3D reconstruction of the pavement surface which introduces high equipment and computation costs. This paper presents a methodology for detection of patch type distresses in asphalt pavement images. This method uses filtering and histogram equalization for clearing and enhancing the image accordingly. It continues by applying the morphological process of closing, along with some rules based on the characteristics of a patch when captured in an image, to finally detect the area it occupies. Criteria for area, length, and width of a patch as seen in an image are taken into account to decide whether a probable patch is actually a patch. The method has been implemented in C#. The preliminary experiments demonstrate it produces promising recognition results

Aug 1, 2013

By E. Quaquero

This article reports on the current state of an ongoing research project which is aimed at implementing intelligent models for hardly predictable hazard scenarios identification in construction sites. As past evidences showed that no programmatic action can deal with the unpredictable nature of many risk dynamics, we tried to survey on how the current approach for safety management in the construction industry could be improved. In our previous research the use of Bayesian networks elicited from subjective knowledge were preliminarily tested. Those networks might be meant as a reliable knowledge map about accident dynamics and they showed that a relevant ratio of occurrences fall in ?hardly predictable hazards? class, which cannot be warded off by programmatic safety measures. This paper reports the second outcome of our research project, which focused on the development of first elementary fragments, regarding the occurrence of a possible ?hardly predictable scenario?. Instead of experts? contributions (who, over their carrier, seldom incurred in accidents), we used ?legal cases? as an accurate source of information. They suggested which categories of ?hidden hazard scenarios? are more likely to happen. We found that the most frequent hidden hazard scenarios are linked to operator?s negligence and abnormal behavior, e.g. irregular removal of scaffolding?s components, unprotected openings, improper use of PPE, etc. Every pattern determined by legal cases has been formalized by a fragment (i.e. elementary network) of the overall Bayesian network. Finally, all the elementary networks were integrated into a comprehensive intelligent tool for realtime hardly predictable hazards prevention. The final setup, asked for interfacing these intelligent models to a low-level sensor network and used to feed them with inputs about the current state of the context, is discussed too.

Aug 1, 2013

By R. C. Becker

Welding is playing an important role in the manufacture of construction equipment as used in the mining industry. It provides design possibilities which are unique to this method of manufacture, and normally makes possible lighter weight but stronger products, which can be a definite advantage to a user. Welding is an industry that has experienced major developments over the past decade, all of which have improved our capability to make better welds and make them more economically. International Harvester Company has been introducing these newer welding methods into its manufacturing plants, particularly those producing construction equipment, just as fast as their value has been proven. This paper discusses how modern welding methods are contributing to the manufacture of strip mining equipment.

Jan 1, 1966

By P. Garritsen, J .. A. Blanco, M. C. Bell

"By 1994, Inco Limited will lower sulphur dioxide emissions from the Copper Cliffsmelter by 60% to 265 000 tonnes/year, primarily through implementing two key process changes. First, new milling technology will permit economic rejection of additonal pyrrhotite prior to smelting. Second, a bulk coppernickel concentrate will be oxygen flash-smelted, thereby eliminating the existing multi-hearth roasters and reverberatory furnaces . All copper will be recovered in the matte separation plant as a nickeliferous chalcocite, and will be oxygen flash-smelted for blister production. This paper outlines the development of the project and describes the process, including the flash furnaces, new sulphuric acid plant and additional oxygen plant.IntroductionInco 's SO2 Abatement Program will lower sulphur dioxide emissions at Sudbury from the current levels of 685 000 tonnes per year to 265 000 tonnes per year by 1994 as required by Ontario' s countdown on acid rain regulations.It is the high tonnage of sulphur mined that creates the magnitude of the SO2 emission problem at Sudbury. At a production rate of 240 million pounds of nickel per year, Inco mines 12 million tonnes of ore. At 10% sulphur it mines 1.2 million tonnes per year of sulphur. If Inco did not fix any of this sulphur it would be emitting 2.4 million tonnes per year of sulphur dioxide-about as much as all other Canadian emissions. Today, however, Inco is already fixing 70% of the SO2 in ore, in several ways : mostly as sulphur in pyrrhotite rejected to tailings in the milling operations; as acid from the roasting of pyrrhotite and some nickel concentrate at the Iron Ore Recovery Plant (lORP) and some as liquid S02 from the copper flash smelting furnace. By fixing 70% of the sulphur the current allowable SO2 emission levels of 685 000 tonnes per year is met. Total sulphuric acid production is currently 450 000 tonnes per year and in fact, the 10RP operation is being continued only to maintain established acid markets.Historically emissions have been reduced from the 2 000 000 tonne per year level to the current level of 685 000 tonnes per year by rejecting pyrrhotite from the smelter feed, and 70% of the SO2 containment problem at Sudbury has already been addressed.While Inco's profits are large at current nickel prices, most people have forgotten that back in 1982 Inco was losing a million dollars a day. Inco did make a dramatic response to this economic stimulus. The Ontario Division increased productivity by 65% and lowered costs to become the lowest cost nickel producer."

Jan 1, 1990

By Lauri Gregg

The implementation of Energy Management within the global mining industry has advanced significantly during the past 20 years. Consequently, the industry?s knowledge of energy efficiency improvement opportunities, more energy efficient technologies, renewable energy technologies, energy procurement practices, and most importantly, practical approaches for integrating the energy management best practices into business processes and operational procedures has improved greatly. Based on 25 years of experience leading the management of energy in mining operations and the Canadian mining community, the author discusses the key building blocks in the evolution toward becoming an energy efficient mining facility. Sustainable energy management depends on the internalization of the behaviors related to the effective energy use by a mining organization. The paper outlines the typical business drivers that stimulate top management commitment to allocate the resources necessary for this to happen. It also explores the barriers that mining companies must overcome to maintain the commitment. Additionally, it will advocate the need for the application of the principles of organizational change management as part of the energy management implementation process. The question regarding how energy management can be made to happen in a way that is practical for an established organization is answered by providing the details of the framework for energy management, the methodology for controlling energy use, and the roadmap for integrating energy as a key business parameter and production process input variable. An Energy Management System standard developed within the Mining Association of Canada?s ( MAC ) Towards Sustainable Mining ( TSM ) initiative has played an important role in increasing the capacity of the Canadian mining industry to manage energy. The impact of the application the MAC TSM Energy/GHG Management Protocol by Canadian mining companies will be discussed. In June of 2011, the international ISO 50001 Energy Management Systems standard was finalized and published for use. The structure of ISO 50001 will be outlined along with its applicability to the mining industry. Opportunities for practically improving mining energy performance along with the most appropriate current new technologies will be identified. A brief discussion of case studies will be included that demonstrates the successful implementation of Energy Conservation Measures ( EAC?s ) and economic benefits. In conclusion, thoughts on important areas of research and development related to increasing mining energy efficiency will be provided.

Aug 1, 2013

By A. A. Sirkeci, M. Tarkan, N. Acarkan, O. Kangal, G. Bulut

This investigation deals with the evaluation of the tailings of the Kirka Borax Plants. In this respect boron in the tailings was recovered and the utilization of the clayish fraction was investigated. There are five tailings ponds in Kirka four of which are used for the tailings of the borax concentrator and the remaining one is used for the tailings of the sodium penta-borax plant. Experiments were conducted with samples taken from ponds containing coarse fraction and fine fraction. Coarse fraction of Borax Concentrator were screened through a set of sieves. The fraction above 1 mm was removed with 41.5% recovery and 33.3% B203 content. Scrubbing was applied above 0.1 mm and products containing 32 to 34% B203 were obtained with recoveries around 35%. The tailings of sodium penta borax plant was also screened and it was found that 15% of boron reported to +1 mm size fraction with 35% B203 content. Sample containing fine tailings was treated by cycloning. The cyclone overflow was found to be below 6µm and it was separated to be used in the subsequent tests. The usage of cyclone overflow in paper, ceramics, glass, pigment and drilling industries was investigated. Since this fraction is mainly composed of carbonate minerals rather than clay minerals it was suggested that it may be used for construction and moulding purposes. Furthermore, the B203 content of the cyclone overflow was reduced to 2.4%.

Jan 1, 2004

By P. R. A. Andrews, R. K. Collings

"There are more than 300 occurrences of fluorite in Canada. Deposits of economic significance, however, are confined to Newfoundland and Nova Scotia in eastern Canada, Ontario in central Canada, and British Columbia in western Canada. Fluorite has been mined and processed intermittently in Ontario and Newfoundland until November 1990, when Canada's only producer Minworth Ltd., a U.K. based company, with a mine and concentrator near St. Lawrence on the Burin Peninsula, Newfoundland, closed its operation.CANMET has processed ore samples from each of the major mineralized areas, and thirty-one studies were conducted between 1920and 1970. A summary of the important aspects of the various testwork studies is presented. The production of acid-grade fluorite was possible by flotation, and ceramic-grade, by flotation and gravity concentration methods. Gravity concentration methods included heavy media separation, jigging and tabling. Flotation was by direct and reverse techniques; associated minerals, quartz, calcite, barite, etc. were depressed by a variety of depressants. The function of the major depressants is discussed briefly. The various uses offluorite which include hydrofluoric acid, chlorofluorocarbons, aluminum production, petroleum alkylation, fluxing and ceramic applications etc. are discussed briefly."

Jan 1, 1993

By George B. Saunders

It is the purpose of this paper to point out conditions as they exist in the merchandizing of coal, to compare these conditions with methods in use by competitive producers of coal substitutes, and to present briefly some suggestions which may help the individual operator to market more coal in the immediate future, while we are waiting for the scientist and research worker, who are now busy on coal betterment , to produce in a practical way the results which they now write about in such glowing terms. While it may be unnecessary to call the attention of coal operators to the present deplorable condition of the industry, it might be well to impress upon our members in other branches of mining, as well as upon the public at large, the seriousness of the situation. Emerging from the war and the period of reconstruction that followed, the coal industry found itself with too many mines and too many men for normal conditions. To make matters worse, the interruptions in deliveries caused by strikes, the unfavourable publicity caused by socialistic propaganda, and the repeated governmental investigations, made the market a fertile field for coal substitutes which were not so handicapped. These substitutes were well advertised, and were marketed in an up-to-date manner, furnishing an example from which the coal operator could well profit. Now, whether or not there is agreement as to the cause or causes of this condition, there can be no doubt that we are today face to face with the fact that the sale of coal has not kept pace with the sale and use of other commodities. Had it done so, we would ere this have been able to take care of the surplus labour and work our mines at least approximately full time.

Jan 1, 1929

By C. F. Gleeson

"Geochemical stream-sediment reconnaissance can be a useful exploration tool from the point of view of rapidly and cheaply evaluating the mineral potential of an area. This is particularly true of rugged and mountainous areas such as are found in Gaspé. For the past two years, SOQUEM has been carrying out such surveys over favorable geological regions in the Appalachians of northern New Brunswick and Gaspe. To date, about 4,000 square miles of terrain has been systematically covered by reconnaissance geochemistry. Jeeps have been used as a means of transportation in the easily accessible areas and a helicopter equipped with a winch has been used to lower crews into the more difficult-to-reach regions. Such surveys have been successful in finding metallic mineralization which otherwise might not have been detected.Electronic computation of analytical information has been used to construct regional metal maps, rolling mean maps and residual metal maps. These maps have helped in evaluating anomalies, in relating the regional geo-chemistry to the regional geology and in comparing the distribution patterns of metals. To date, some 30,000 stream-sediment samples have been collected from the Gaspe region and analyzed for Cu, Pb, Zn and Mn. These analyses are being subjected to computer analysis."

Jan 1, 1969

By D. C. Crothers

"What is new in air compressors? A good deal - the designers have been keeping pace with technical developments in related fields and also contributing new techniques of their own. Plant reliability no longer requires bulky slow-speed machines. Even the reciprocating machines, which still provide the most efficient method of compressing air, have been greatly reduced in size and installation cost for a given capacity rating. New materials and fabrication techniques are being used, by most manufacturers, to produce less costly plants in total. Many packaged plants are available, which generally means a more complete assembly for shipment. This type of construction offers savings in handling and erection costs at the site. A warning is in order, however - the extent of packaging in any given plant should be investigated carefully to determine what is included and just what field costs can be realized. A suggested specification has been offered for consideration when studying comparative costs. Rotating machines intrigue many because of their potential as regard fewer wearing parts, higher speeds and hence smaller units, utilizing less expensive drivers, and lack of contamination of the compressed air by lubricants. The inherent shortcomings of these machines - lower •efficiency and capacity control - have been much improved lately, and this type of plant is now becoming quite popular. Noise control, of much concern to everyone, is another development that has received considerable attention.Systems for efficient capacity control and continuous monitoring of compressor operation offer additional reliability and low-cost operation of the modern compressed air plant. Accessory equipment and its effect on over-all plant operation is also considered."

Jan 1, 1972

By A. Y. Senchenko, Y. V. Kulikov

"Different methods aiming at specific energy calculation and design of AG/SAG circuits are used in mining. They include JK DWT/SMC test, SAGDesign test and CWi/RWi/BWi tests. The simplest methods with no secret equations and giving energy required for grinding in kWh/t were proposed by F.?. Bond and J.H. Starkey. D.J. Barratt proposed to use results of CWi/RWi/BWi tests for AG/SAG mill sizing. The present paper gives an alternative for forecast of specific AG/SAG energy. The principle is similar to the theory proposed earlier and consists in cumulative AG/SAG energy calculation using indices of rod and ball grinding (RWi+BWi) without impact crushing index (CWi). Then total energy is divided between two grinding stages using special formulas based on extensive statistical information. The forecast indices of AG/SAG and ball grinding are similar to the SAGDesign testing results. Hereinafter the predicted indices are used for mill sizing of the whole grinding circuit. The method considered in the paper enables prediction of AG/SAG energy based on the test results according to Bond method. The proposed method version was not widely published earlier. The aim of the work was to elaborate cost-effective, reliable and accessible way to determine specific AG/SAG energy. At this stage of method development, it is recommended to use it only for works at preliminary Geometallurgy stage (Scoping, Pre-Feasibility). At design stage the obtained data should be confirmed by appropriate testing using alternative JK DWT/SMC and SAGDesign methods.INTRODUCTIONAppropriate crushing and grinding testing is required to design efficient comminution circuits. It is obviously important to obtain accurate information about ore hardness properties since the main energy consumption at the plant is associated with comminution processes. Moreover, it is required to apply the processes that make it possible to minimize operating costs and efficiently use capacity of the installed equipment installed.When studying ore hardness properties, it is required to take into account that breakage of the material is performed using different equipment. That is why accurate selection of the equipment and the circuit calculation without relevant testworks is impossible. Ideally, the testworks should provide answers to the following questions: determination of ore hardness properties, determination of specific energy consumption for comminution as well as obtaining of sufficient amount of statistically significant results from the tests. The results from crushability and grindability testworks in the first place provide assessment of ore hardness properties and in addition correlate with throughput of the respective equipment. The data obtained can be used for modeling of comminution circuits at the stage of the technology development"

Jan 1, 2016

By E. You

The concentrator at Kennecott Utah Copper currently has 4 lines with a configuration of one SAG mill feeding two ball mills. The slurry that reports to each ball mill will vary resulting in an unequal load of material. This configuration contains two separate sumps that receive material from a distribution box relying solely on natural slurry flow to feed each sump. The unequal split to each mill results in one mill receiving a greater amount of material. This will result in the equipment on one mill reaching limitations that may affect product quality and the operation of the equipment near maximum. The parallel mill in this condition will often have additional capacity that can be used but cannot be utilized due to the unequal split. The major consequences of this issue result in reduced throughputs and metal recovery. To resolve this condition an advanced control strategy was implemented to control the split in April of 2002 using equipment that was in place.

Jan 1, 2007