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By J. R. Kadambi, E. Kucukal, J. Furlan

"Hydrocyclones are used in various industrial applications, including mineral processing and tailings management, to separate or classify solid particles and/or liquid droplets from multiphase feed. The fluid flow in a hydrocyclone (used in mineral processing) was investigated numerically and experimentally using particle-image velocimetry (PIV) and refractive index matching techniques. Two turbulence models were used in the calculations: the k–? model and the Reynolds stress model. Particle image velocimetry measurements were taken at various spatial locations along the cyclone. Computational results were validated globally using pressure and flow-rate readings at the boundaries, and locally by comparing the PIV velocity-vector maps and profiles.RÉSUMÉ On utilise les hydrocyclones dans diverses applications industrielles, dont la minéralurgie et la gestion des résidus, pour séparer les particules solides et/ou les gouttelettes liquides de l’alimentation polyphasée, ou pour les classifier. Une étude numérique et expérimentale sur l’écoulement des fluides dans un hydrocyclone (dont on se sert en minéralurgie) a été menée à l’aide des techniques de vélocimétrie par images de particules (PIV, de l’anglais particle image velocimetry) et d’appariement des indices de réfraction. Deux modèles de turbulence ont été utilisés dans ces calculs, à savoir le modèle de turbulence k–? et le modèle aux tensions de Reynolds (RSM, de l’anglais Reynolds stress model). La valeur de la PIV a été mesurée à diverses positions spatiales le long du cyclone. Les résultats de ces calculs ont été validés globalement à l’aide de relevés des pressions et du coefficient d’écoulement d’une extrémité à l’autre de l’hydrocyclone, et localement à des coordonnées spatiales spécifiques en comparant les cartes et les profils du vecteur vitesse PIV."

Jan 1, 2017

By Fathi Habashi

"Hydrochloric acid (HCl), although more expensive than sulfuric, find uses as a leaching agent in reactions involving iron oxide. The reason for this substitution was the discovery that oxyhydrolysis of ferrous chloride by which HCl can be recycled economically. This avoided the pollution of the environment by ferrous sulfate. It was found further that the rate of leaching of sulfides is faster when HCl is used as compared with sulfuric apparently due to the formation of aqueous chlorine. In case of refractory gold ores, HCl leaching under pressure avoids the use of cyanide solution since gold chloride is produced which can be recovered by standard methods. Hydrochloric acid find also uses in the leaching of scheelite and apatite but its use in leaching clay and anorthosite is questionable.INTRODUCTION Sulfuric acid is the cheapest acid and is used as a leaching agent in many hydrometallurgical processes. However, hydrochloric acid (HCl), although more expensive since it is prepared by reaction of sulfuric with sodium chloride, has replaced sulfuric acid in many reactions involving iron oxide. It replaced sulfuric acid for the first time in 1960s in pickling of steel because of pollution problems (Habashi, 2000). Ferrous chloride produced in pickling can be economically decomposed to ferric oxide and HCl according to:2FeCl2 + 2H2O + 1/2O2 ? Fe2O3 + 4HCl (1)which also shows that the acid can be regenerated but ferrous sulfate cannot be economically decomposed to recover sulfuric acid for recycle. Since then, HCl has been used in many leaching processes. Hydrochloric acid is a corrosive acid and is usually handled in rubber-lined equipment. REGENERATION OF HYDROCHLORIC ACID Regeneration of HCl is conducted in fluidized bed or in spray roaster Fluidized bed oxyhydrolysis In a fluidized bed, ferrous chloride solution is introduced onto a bed of hot ferric oxide where heating is provided by the hot fluidizing combustion gases (Figure 1). The solution is fed on top of the bed of oxides. The liquid feed wets the outer layer of the hot oxide particles and is quickly evaporated to form a layer of new solid oxide on top of the existing oxide, thereby producing dense homogeneous particles."

Jan 1, 2017

By A. M. Cormie

Introduction The purpose of this paper is to give a brief, general outline of mining practices at Torbrit Silver mine. The geology of the mine is touched on as it is felt that a rough picture of the geology will result in a clearer understanding of the mining methods employed. The main part of the paper deals with mining methods and a section is included on haulage. Development practice is mentioned only briefly. Torbrit Silver Mines, Limited, a subsidiary of Mining Corporation of Canada, is located in the Alice Arm area of northern British Columbia. Access to the mine is by boat to the village of Alice Arm at the head of Alice arm, then truck road, following the course of Kitsault river for 18 miles in a northerly direction to the plant site. The main portal is a further two-thirds of a mile along the course of the river, at approximately the same elevation as the plant, 1,014 feet above sea level. Geology The ore occurs in a massive, irregular-shaped quartz-barite body replacing a folded area in a series of volcanic breccias, tuffs, and flow rocks locally referred to as 'green-stones'. A series of parallel, nearly vertical, fine-grained basic dykes cut across the formation at right angles to the strike of the ore belt over a horizontal distance of 140 feet. The whole of the quartz-barite vein material, which ranges up to several hundred feet wide in places, carries silver values but commercial grade is confined to lenses and shoots where there have been more than usual concentrations of native silver and silver-bearing minerals. The ore-bearing structure plunges at approximately 25 degrees along an axis striking roughly N.65°W.

Jan 1, 1951

By J. G. A. Stevenson

GENERAL Location of Property THE Stirling zinc-lead-copper deposit is in Richmond county, Cape Breton, about a quarter of a mile southwest from Stirling P.O., and some 45 miles southwest from Sydney. The property is accessible by road for at least nine months of the year, and during the navigation period coastal boats maintain a service touching at the port of Fourchu, eleven miles from the mine. When flying conditions permit, the Cape Breton Flying Club, of Sydney, will carry passengers to or from the property, a service which has been particularly advantageous on two occasions when hospitalization was urgently required. The Company has mining rights on leases Nos. 73-74, 78-80, and 101-104, inclusive, and owns 166 acres at Stirling and one acre at Fourchu. The ore deposit is in lease No. 73. History The Stirling deposit was discovered in the 'nineties', probably about 1895. The original discovery is said to have been made in the bed of Copper creek, which traverses the ore-zone. For a number of years, indifferent development work was carried on with a view to copper production only, and it was not until1915-16 that attention was directed to the possible production of zinc. Previously, the ore had been considered too complex for metallurgical treatment. During the period 1916-24 several operators attempted to develop the property, among them being the Stirling Exploration Company, Stirling Mining & Smelting Company, New Jersey Zinc Company of New York, Hayden & Stone Company of Boston, and The Eastern Mining & Milling Company. Up to 1924, the work was limited mainly to trenching, stripping, ? diamond drilling, and shot drilling.

Jan 1, 1937

By Rodrigo Craig Cerello

The Brazilian economy has always presented a strong correlation with the mineral activity. Since colonization days, due to the territorial expansion caused by the explorers search for gold, mining in Brazil became a basic sector of national economy. Currently, the Brazilian mineral sector¹ estimates a 550% production increment (Figure 1A) in the last 10 years, reaching the US$ 50 billion value, reflecting the increased global demand for raw materials from mineral origin. According to the Brazilian Constitution², mineral resources belong to the Federal State and, consequently, their exploitation must be authorized, under penalty of engendering federal crime. Furthermore, activities of this nature are prone to cause environmental degradation such as, but not limited to, deforestation, pollution, soil deterioration and water contamination. The GPEMA represents the forensics group of the Brazilian Federal Police responsible for the technical analysis of traces related to crimes against the environment and consequently, illegal mining cases.

Aug 1, 2013

By Walter Valery, Sergio Vicuna, Roberto Valle, Hamer Arevalo, Ben Burger, Lui Vargas, Alex Jankovic, Jim Seidel, Eduardo Nozawa

This paper describes the design, the first three years of operation and optimization of a large, single stage SAG mill at Minera Yanacocha’s Gold Mill facility located in northern Peru. The Gold Mill was commissioned in March 2008 with a 32’ x 32’ EGL, 16.5MW single stage SAG mill, to process 5 million tonnes per annum high grade oxide Au/Ag ore. Operational control, feed size distribution, grinding media, mill liner, grate and pulp lifter optimisation have allowed the mill to operate 15-30% above design throughput rates, but with a product P80 coarser than design. As part of the optimization, full grinding circuit surveys were conducted. Historical operating data and survey data were analyzed and used to evaluate possible circuit changes and determine alternative operating strategies. A number of changes were implemented which allowed the SAG mill to operate similarly to a large ball mill and achieve finer mill product that was closer to design. This paper summarizes life to date data analysis and improvements made by Minera Yanacocha as well as the grinding circuit optimisation study conducted by Metso Process Technology and Innovation.

Jan 1, 2012

By G. F. Trainor

The complex ore body at CNRL?s Horizon mine presents some unique challenges in managing ore and waste delivery. With 25m x 25m ore blocks shovels often take bucket loads from multiple blocks to fill one truck load. With CNRL monitoring 22 different qualities per material a precise calculation of the blended quality of ore on the back of each individual truck is essential to meet the daily blend requirements at the plant. Additionally, one of these qualities must be closely monitored and controlled at a singular level as delivery of certain grade and quantities can cause serious disruptions at the plant. The waste material also requires special handling and delivery for its use in dyke construction for tailings impoundment. Shale materials used in the construction contain high levels of saline that must be contained to prevent seepage into ground water. This paper will discuss how the use of Wenco?s survey-grade GNSS system on shovels, its dispatching algorithm, and fleet management applications give CNRL the ability and confidence to control and report on these three issues.

May 1, 2013

By Matt Schuett

Antamina Mine Facts • Surface Water Design Principles • Drainage Areas • SEDCAD Modeling • Impacted Runoff Collection • Clean Runoff Collection • System Flexibility • Outfall Construction

May 1, 2004

By Q. F. Wang, M. H. Lai, T. Q. Liu, G. G. Dong

Compared with the traditional pre-treatment process, biological oxidation process has many advantages including higher gold recovery, less cost, easier operation. The bio-oxidation reactor is the most important equipment for biological oxidation process. In this paper, the characteristics of biological oxidation are investigated, and the design principles are proposed based on laboratory tests. Both increasing the tank height and taking new inflation system can enhance higher dissolved oxygen. The new type of large-scale industrial bio-oxidation reactor is designed, which is 9.5 m in diameter and 10 m in height. The bio-oxidation reactor metallurgical performance has been tested by industrial-scale experiment. The slurry of flotation concentrate is divided into two parts to feed two bio-oxidation reactors. The feeding rates of two reactors are adjusted on the basis of getting the same content of S, Fe, As in overflow. The result shows that the feeding rate of the new type of 700 m3 bio-oxidation reactor is 3.72 m3 per hour, and the feed rate of the conventional 700 m3 bio-oxidation reactor was 3.23 m3 per hour. The processing capacity of the former is 15.2% higher than that of the later, which demonstrates the new type of bio-oxidation reactor has higher oxidation rate.

Jan 1, 2015

By E. L. Jones

THE concentration of tin in the tailing from Sullivan ore has been de-scribed by H. R. Banks, superintendent of the Sullivan concentrator, in a paper presented at the annual meeting of the B.C. Division of the Institute in October, 1941(1). The reduction of the concentrate EARLY EXPERIMENTAL WORK Experimental work on the smelting of Sullivan tin concentrate was done in Trail. Preliminary tests in the laboratory indicated that the concentrate could be successfully treated in an electric furnace. A small electro-thermic pilot plant was built and, at the same time, reduction tests were made in an oil-fired reverberatory furnace. Both types of treatment gave satisfactory results. It developed that no fluxes, other than those already in the ore and in the ash of the reducing agent (either coke or coal), were needed. By using an excess of iron, a complete recovery of the tin in the slag was obtained, but with 20 to 30 per cent iron in the tin. A counter-current treatment was thus indicated, viz., the primary slag was first treated with hard-head (iron-tin alloy) from the refining and final slag smelting, producing tin with 2 to 4 per cent Fe. This secondary slag was subsequently treated with scrap iron to produce tin-iron alloy, and a final slag low enough in tin to waste. By following this line of endeavour, a tentative flow-sheet was drawn up and a successful operation was established. Without resorting to electrolytic refining, a metal comparable in purity to standard tin was produced. Metallurgical results and operating costs were found to be very similar with an electric furnace or a fuel-fired furnace. 'However, electric furnace smelting was chosen because the furnace required was smaller, and because some doubt existed as to the cleaning of the final slag in the reverberatory furnace reduction.

Jan 1, 1944

By Mory Ghomshei

As fossil fuels become depleted over the next century, it is imperative that Canada and other countries examine ways to transition to other sources of energy, particularly renewable resources. A critical obstacle to developing Canada?s renewable energy resources is the scarcity of infrastructure to wheel the generated electricity to a viable market. For each megawatt of renewable electrical power, a maximum of 1 km of connecting power line is typically feasible. This means that hydropower, geothermal, and wind power projects with capacities up to 100 MW must be located within a maximum of 100 km of a main power line in order to be economically viable. With a total length of about 1200 km, the proposed Northern Gateway oil pipeline project creates an excellent opportunity to become a corridor that can seed renewable energy projects in Northern British Columbia and Alberta. Utility companies must build new infrastructure to provide the electricity for constructing and operating the proposed pipeline. The pipeline and linked power line infrastructure therefore, should be designed and built with consideration to create an energy highway to the significant renewable energy resources, such as hydro, wind, and geothermal, in the vicinity of the proposed pipeline. Some of the important renewable energy resources in northern British Columbia can be developed in connection with the proposed pipeline. It is estimated that close to 2,500 MW of commercially viable wind, geothermal and run-of-river power resources are present in the proximity of the proposed pipeline corridor. While oil flows westward from the Alberta bitumen fields, the generated green power can flow eastward to help the Canadian oil sand industry to offset as much as 10 Megatons of carbon emissions per year. The generated carbon credits are equivalent to 75% of the emissions associated with extraction of the 525,000 barrels per day of oil from oil sands, intended to be carried by the pipeline.

Aug 1, 2013

By G. Wilson

"Satisfactory hydraulic performance of a centrifugal slurry pump is not the only design criterion. If abrasive wear exists the severity of any damage can be reduced and the life of the wearing parts prolonged by selecting the correct pump to suit the conditions of service. This paper is concerned with the design and construction of centrifugal pumps for handling abrasive solids. The wear phenomena due to the slurry being pumped and the materials used to combat abrasive, wear are outlined. The hydraulic design of the impeller and casing and their relationship to wear and the hydraulic radial and axial unbalance are discussed. The prediction of abrasive wear in pumps can not be precise, as many factors are involved - and this is the object of current research."

Jan 1, 1973

Agenda ?The Context ?The Challenge ?The Solution ?Benefits and lessons learnt from pilots ?Next Steps The Context ?Facilitate management decision making process by supporting the development of value/risk based business cases. ?Large scale investments by extractive industries are expected tobring broad-based benefits to local communities (e.g.: health, education, jobs, infrastructure) ?Investors continue to expect the demonstration of social performance?Specific interventions bring direct value to companies (e.g. skills development) ?Social Investments are key to protecting a company?s license to operate ?Quantifying the value of these investments and planning accordingly, however, has long posed a challenge for the extractive industries and community development practitioners

May 1, 2011

By R. D. Brown

"When elephants fight, it's the grass that gets trampled". It is becoming increasingly evident that the federal and provincial governments are awakening to the fact that their vigorous scramble for a "fair share" of mineral revenues which kicked off in 1974 has done considerable harm to the Canadian mining industry. Recent public statements made by government officials, particularly at the recently held annual convention of the Prospectors and Developers Association, would indicate that there is a general consensus in the government sector that changes must be made to the mining tax system. However, there is no evidence as yet that there is any agreement among the various governments as to what form these changes should take , who should make them , or when. It would seem to be worthwhile at this time to reflect on where the Canadian mining industry has been vis-a-vis taxes and "where it is at ". This article is based on a recent address given by R. D. Brown, of Price Waterhouse & Co., Toronto, at the annual convention of the American Institute of Mining, Metallurgical and Petroleum Engineers in Denver , Colorado.

Jan 1, 1978

By Iain Sommerville, Hugh Mountford, Dawid D. Smith, Claude Dube, Brett Hixson

JW Aluminum use lean and Six Sigma techniques to continuously improve their target of reliable, repeatable and reproducible (3R) manufacturing. Six Sigma’s second stage gate, known as "Measure" involves identification and qualifying appropriate measuring systems. Metal quality (inclusions) are known in the industry to be an important element in 3R casting. The measurement of inclusions at JW Aluminum historically depended on outside vendors. In order to establish real time inclusion measurement ability within JW Aluminum, inclusion measurement systems in the marketplace were investigated. The qualification of a MetalVision MV20/20 ultrasonic inclusion analyzer are discussed as well as the subsequent application of the system in melting and casting improvement projects.

Jan 1, 2015

Carrying Energy ?Energy ?Power, data, signal, hydraulics, pneumatics? ?Needs to be conveyed from a stationary point to a system in motion ?Cable Carriers (steel and plastic), Festoon Systems, Cable Reels and Bus Bars Polymer Cable Carriers ?Life Line for modern machinery ?Transmitting power, data, signal, hydraulics or pneumatic energy ?Constructed and designed to work in harsh environments, at high speeds and to do this continuously ?Meet a wide variety of cable (Media) requirements ?Virtually maintenance free ?High efficiency

Nov 1, 2011

By J. O. Yeboah, V. Boakye, P. A. Bepswa, M. Lombard, G. Nutor

The comminution circuit at Tarkwa Gold Mine was commissioned as a Single Stage SAG mill operated in closed circuit with hydrocyclones designed to process 4Mtpa. The circuit was later expanded by adding a secondary ball mill in closed circuit with hydrocyclones with a view to treat 12Mtpa. The change in the circuit configuration and assigning the low aspect ratio SAG mill for primary grinding application makes the Tarkwa experience unique in terms the optimisation strategy and operating philosophy. This paper reports the findings from a series of surveys performed on this plant. The surveys reported include data obtained when the SAG mill was operated as a single stage mill in closed circuit with hydrocyclones and also SABC mode under two different feed conditions. The differences in operating philosophy between the initial single stage SAG circuit and the current SAG/Ball mill circuit are discussed.

Jan 1, 2012

By C. Tasker

Introduction In the Early part of 1930 the Ontario Research Foundation was asked by the Minister of Mines, the Hon. Charles McCrea, K.C., M.P.P., to undertake a technical and economic investigation of the Northern Ontario lignite deposit. This investigation has been under way since June, 1930, and has necessitated considerable work at the deposit, in the laboratories of the Foundation, and at test plants in Europe. All the work has been carried out in active co-operation with the Provincial Department of Mines, the Deputy Minister, Mr. T. F. Sutherland, and several of his technical colleagues being associated with members of the staff of the Foundation on the Advisory Committee, which has met at frequent intervals to co-ordinate and direct the various lines of research. An interim report was made to the Minister of Mines by the Director of the Foundation, Dr. H. B. Speakman, at the end of December, 1932, and is at present under consideration by the Minister. This report deals with the extent and character of the deposit, the methods and costs of mining, and the methods and costs of processing raw lignite, the characteristics of certain lignite products, and the technology and economics of present fuel utilization by railways, industry, and domestic users in northern Ontario. It is not the purpose of the author to discuss in this paper either the geology of the deposit or the economics of the mining, processing, and utilization of lignite, but rather to deal briefly with some of the technical problems investigated by the Foundation during the study of the characteristics and methods of utilization of Northern Ontario lignite. Some mention, however, of the work carried out to define the extent of the deposit is a prerequisite to any discussion of the nature of the lignite.

Jan 1, 1933

By C. Stapel, P. D. Roberts, D. G. Jones, W. G. Macdonald, R. J. De Meijer

"Abstract-Measurement of natural radioactivity has been used in both a qualitative and a quantitative way in mineral exploration, particularly in the search for uranium. In the last five years, the Kernfysisch Versneller Instituut (KVI) and British Geological Survey (BGS) have designed, built and tested a new detector system that greatly improves quantitative applications in mineral exploration, especially on the seafloor and in the nearshore zone. The new system is an enhancement of an earlier BGS design. The major improvements comprise the use of a highly sensitive ?-ray detector, together with new data processing, from which concentrations of natural radionuclides may be deduced in real time. After laboratory analysis of samples, these concentrations can be converted into mineral percentages. Once the mineralogy of an area has been characterized, this conversion can also be done in real time.Thus far the system has mainly been used to map heavy-mineral concentrations in coastal subtidaland intertidal sediments. For such work the multi-sensor detector probe is towed on the seafloor and various parameters are recorded continuously. The probe contains, in addition to the gamma-ray detector, a water-pressure sensor (giving water depth) and an acoustic device to measure bottom roughness. The system, when used together with high-precision positioning systems such as D-GPS, enables the production of detailed maps of bathymetry, bottom roughness, and seafloor radioactivity or mineral distribution. These maps allow mineral concentrations to be readily correlated with seabed topography and sediment type. In the same way, ?-ray detectors could be used advantageously during dredging operations to provide on-line assessment of the mineral content of the dredged sediment as well as to guide the direction of dredging. Additionally, the same technique could be used to monitor the subsequent fate of a dredge spoil after dumping on the seafloor.Natural radioactivity arising from potassium and the thorium and uranium decay series has potential use for the fast and reliable assessment of siliciclastic and phosphatic impurities in limestones. Detection of such impurities may preclude the use of the limestone for chemical or cement production.Apart from its use in exploration, the technique has significant potential in mineral processing, particularly of heavy minerals. It can be applied as on-line quality control in dry and wet separation processes and for process control, by using decisions based on the results to control valves and other instrumentation. In addition, it can also be used in environmental monitoring of waste arising from mineral extraction and processing. In conclusion, the technique described has a diversity of applications in exploration, mining and mineral processing."

Jan 1, 1997

By C. Stapel, P. D. Roberts, D. G. Jones, W. G. Macdonald, R. J. De Meijer

"Measurement of natural radioactivity has been used in both a qualitative and a quantitative way in mineral exploration, particularly in the search for uranium. In the last ?ve years, the Kernfysisch Versneller Instituut (KVI) and British Geological Survey (BGS) have designed, built and tested a new detector system that greatly improves quantitative applications in mineral exploration, especially on the sea?oor and in the nearshore zone. The new system is an enhancement of an earlier BGS design. The major improvements comprise the use of a highly sensitive ?-ray detector, together with new data processing, from which concentrations of natural radio nuclides may be deduced in real time. After laboratory analysis of samples, these concentrations can be converted into mineral percentages. Once the mineralogy of an area has been characterized, this conversion can also be done in real time.Thus far the system has mainly been used to map heavy-mineral concentrations in coastal subtidal and intertidal sediments. For such work the multi-sensor detector probe is towed on the sea?oor and various parameters are recorded continuously. The probe contains, in addition to the gamma-ray detector, a water-pressure sensor (giving water depth) and an acoustic device to measure bottom roughness. The system, when used together with high-precision positioning systems such as D-GPS,enables the production of detailed maps of bathymetry, bottom roughness, and sea?oor radioactivity or mineral distribution. These maps allow mineral concentrations to be readily correlated with sea-bed topography and sediment type. In the same way, ?-ray detectors could be used advantageously during dredging operations to provide on-line assessment of the mineral content of the dredged sediment as well as to guide the direction of dredging. Additionally, the same technique could be used to monitor the subsequent fate of a dredge spoil after dumping on the sea?oor.Natural radioactivity arising from potassium and the thorium and uranium decay series has potential use for the fast and reliable assessment of siliciclastic and phosphatic impurities in limestones. Detection of such impurities may preclude the use of the limestone for chemical or cement production.Apart from its use in exploration, the technique has signi?cant potential in mineral processing, particularly of heavy minerals. It can be applied as on-line quality control in dry and wet separation processes and for process control, by using decisions based on the results to control valves and other instrumentation. In addition, it can also be used in environmental monitoring of waste arising from mineral extraction and processing. In conclusion, the technique described has a diversity of applications in exploration, mining and mineral processing."

Jan 1, 1997