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By D. L. Griffith

THE realization by metallurgists of the important effect that traces of impurity may have upon the properties of a metal, and their steady demand for purer and still purer metals, have made the special cools for 'trace' analysis of increasing value. In the United States at least, spectrographic analysis is becoming the standard method for determining the impurities in zinc die-casting alloys. The Hudson Bay Mining and Smelting Company, as a producer of virtually pure zinc, uses the spectrograph to control the purity of its products, and-as the electrolytic method is employed here-to control both the impurities in the electrolyte and those 'trace' elements, which, while they do not contaminate the zinc, have a great effect on the plating efficiency. The general plan of the laboratory is shown in Figure l; the housing for air purification, which is on the roof, is indicated by broken lines. One of the chief factors affecting the layout was the easy way in which a spectrographic assay can be spoiled by contamination. To minimize the quantity of dust tracked in, the laboratory was made separate from the general research laboratories, and an office was placed between the two. This arrangement has its drawback because of the traffic through the office, but it has effectively cut down dust. For similar reasons, the available space was subdivided into a number of small rooms, and the air currents in the laboratory were so arranged that dust would be carried where it would do least harm. Air is drawn in at the roof over a 50-kilowatt bank of Calrod heaters, through Annis air filters, by a No. 4 Sirocco fan. Most of it is forced into the spectrograph room, but some goes to the office and darkroom. The air flow is from the spectrograph room, through the plate-measuring room, into the chemical laboratory, where it is exhausted by a No. 1% Sirocco fan on the fume hood. Air can also re-circulate from the plate-measuring room back to the heater. The arrangement is such that the air in the laboratory is maintained at higher pressure than the outside air; consequently, no dirt enters through cracks about the windows and doors. A thermo-regulator holds the temperature constant within one or two degrees; only on the hottest days in summer does the temperature rise enough to affect the focus of the instrument.

Jan 1, 1940

By H. Vendette, N. R. Dando, A. Moras

The thorough analysis of results obtained from different testing campaigns performed on an alumina dry-scrubber pilot installation treating aluminum potline offgases, suggests a clear relationship between the emissions of gaseous fluoride and the fluoride saturation level of the alumina. The integration of this relationship into the development of a new generation of alumina dry scrubber represents an intriguing challenge regarding the design of more efficient air pollution control equipment. An innovative scheme challenging conventional industry practices was proposed. From theoretical simulations, the reduction in fluoride emissions can potentially be reduced by as much as 50% in the summer season. To validate this innovative approach, Solios in partnership with Alcoa Primary Metals, modified one of the Aluminerie de Deschambault's systems by adding new temporary equipment on the operating units and subjecting it to several test campaigns. This article presents the first results obtained in testing this new and innovative approach on alumina dry scrubbers used to capture fluoride emissions coming from aluminum electrolysis potlines.

Jan 1, 2006

By P. C. Parsons, G. C. Milligan

"IN FIELD WORK in the Cape Breton Highlands, which are heavily covered with vegetation, it is necessary to run traverses along the valleys of small brooks. We encountered difficulty in closing such traverses, and the following technique was developed to solve this problem. It has been tested in the field for four seasons by several people, and found to be simple, efficient and more accurate than any other compass-and-pace system of which we are aware. So far as we can find, the technique has not been described previously. It may be of use to others.The Cape Breton Highlands of Nova Scotia consist of hills of old intrusive and metamorphosed sedimentary rocks protruding up to 1,000 feet above the general level of the younger sediments which underlie the valleys. The flat hill-tops are the remnants of a plateau; drainage off the edge of this plateau has produced many small steep brooks. They occupy valleys which are up to 800 feet deep, and V-shaped in cross section, with steep sides covered by mixed conifers and hardwoods. The stream at the bottom is rarely more than a few feet wide, with a negligible meander belt, but with many bends, rapids and falls. Visibility along the stream, in consequence, is rarely more than a few hundred feet, and in many places much less.It was found impractical to map the streams by the method of meander lines, as described in many standard surveying texts and hand-books. The limited visibility, and the numerous bends of the brooks, necessitated many corners. Every corner introduces errors. To 'close' a survey with 40 or 50 such corners proved either very time-consuming or impossible. In most cases, however, the general direction of a valley may be obtained from an aerial photograph, or by direct observation, and this became the basis of the method adopted."

Jan 1, 1971

By Roberto Pena, Cristhian Morales, Darwin Morales, Veronica Cambiaso

"This article makes evident the shortcomings of the current operation of oxygen pipes as well as the damages they cause and why they cause them. When focusing on the causes and effects of these drawbacks, it was possible to develop a new family of thermal lances that could pierce a taphole with the precision of a drill but with the capacity to complete the whole operation. Although efforts have been made to replace oxygen pipes since they are annoying, dangerous and inefficient, nobody had worked to improve the way the traditional oxygen pipe taps/perforates the furnaces and reactors tapholes. In fact, developments made in drills and robotic arms, have failed to replace the oxygen pipe, which despite their negative side effects have been used for more than a century. Observation and theory were key to radically transform this humble tool into a dependable and efficient support in the operation. A good news that it is worthwhile to share for the benefit of all of us, passionate about the world of pyro metallurgy.INTRODUCTION Normally, reports and papers prepared for conventions, symposia or other technical events related to metallurgy aim to relevant topics in the operational field, probably because in them lay the scale economies every company pursues. We intend to give relevance to a matter normally disregarded in operations, but that unmistakably vital: if the furnace or reactor cannot be bled, the pyrometallurgical process will not be completed. Besides, if the tapping task is difficult or is long delayed, the availability of the furnace will be reduced. Consequently, there will be a waste of energy and workers will be exposed to dangerous levels of radiation as well as to work overload and physical injuries Apart from these basic effects, in tapping operations where oxygen pipes are used, we can see serious damages in the smelting furnace, especially in the taphole components such as refractory bricks, taphole jackets and water cooled plates. This paper intends to show that taking care of the tapping task can significantly upgrade not only to the tapping operation itself, but also the whole plant productivity."

Jan 1, 2017

By J. G. Speight

Laboratory studies indicate that autogenous heating of low-rank coal can be prevented by a prior treatment which involves immersing the coal for short (5-15 min.) periods in an inert liquid at temperatures between ~ 350° and 400°C. Such "carbonization" effectively reduces the accessible pore volume of the coal to levels at which heat generation through subsequent sorption of moisture and oxygen is too slow to cause significant temperature rises in a stockpile. In addition, this treatment also irreversibly removes most of the moisture held in the raw coal and raises its calorific value by as much as 10-12%.

Jan 1, 1973

By Stephanie Price

Engineering Associations ?Regulatory authority ?License individuals and firms ?Discipline licensed members ?Enforce against improper acts ?Programs for EIT?s, competence, etc

Oct 1, 2010

By K. Kim

"All milling operations would like to achieve the best possible recovery in combination with the highest achievable throughput. Unfortunately, many operations have problems with low recovery, low throughput or both. In the majority of these cases investigated by the author, the solutions to improve recovery and throughput were simple. The solutions did not include implementation of new technology or major capital, but rather a return to fundamentals. In most cases, problems occurred because the operation was not following their own operating procedures, because the design of the circuit was changed without adequate change management or understanding of the implications of changes, or because basic metallurgical measurements and control were not taken or ignored. In this paper, examples of these problems and their solutions derived from long and varied experience will be discussed. The objective of this presentation is to provide the milling operator with practical and readily implementable solutions to common milling issues to improve throughput and recovery.INTRODUCTION Mill operations can be evaluated by many operating parameters, but the two best indicators are recovery and throughput. These two parameters summarize the wellbeing of an operation. The grade to the mill is also a good indicator, but this is usually controlled by the mine. The best recovery and throughput are achieved through a team work involving operators, maintenance workers and metallurgical staff. The milling operations include many unit operations, such as crushing, grinding, flotation, leaching, carbon in leach, Merrill Crowe, roaster, autoclave and refinery. The tools available to the operations are plant design, process measurements, assays, metallurgical balance, and operating strategy. Twelve real life examples of improvements of recovery and throughput are presented in this paper. EXAMPLE 1: CRUSHING CIRCUIT WITHOUT FINE ORE BIN At this operation plant throughput could not be maintained at a high rate because feed to the mill became coarse during the day. The cone crusher was feeding the ball mill directly. As the day wore on, the gap on the cone crusher would slowly increase, which would cause the product size to increase. This would increase the re-circulating load on the ball mill. The throughput would decrease accordingly. Furthermore, the throughput would decrease more with high frequency of maintenance on the cone crusher."

Jan 1, 2019

By Namavari. H., M. Ashouri, M. R. Sarhadi, S. H. Mansouri, A. Sarrafi

The splash phenomenon and its effective parameters in metallurgical converters have been studied thoroughly for decades. The detailed studies of processes such as tuyere blockage, wave formation during air injection, entrapped phases, and also processes which control the formation of bubbles in viscous fluids are not feasible yet. In this research, we have used a converter-shaped vessel made of flexi-glass. Water and oil have been used as matte and slag phases respectively. The effective operational factors responsible for creation of splashing have been studied such as air flow rate, tuyere angles, depth of tuyere submergence, tuyere blockage, density and viscosity of liquids, liquids heights, etc. The results have been found as follows: the amount of splashing increases slowly as air flow rate increases. However, as the air flow rate reaches a critical value (depending on the physical specification of converter) the amount of splashing rises sharply, because the flow of air inside the liquid changes from bubbling into a jet stream; and most of the splashed materials are in the form of filaments instead of droplets. Changing tuyere angle from horizontal towards vertical position will increase the turbulence level on the fluid surface and causes an increase in the amount of splashing. The effect of tuyere submergence is related to the converter opening angle. As the converter opening angle is shifted towards the hood position, the amount of tuyere submergence and splashing will increase. As density of the liquid increases, the number of droplets splashing increases with a decrease in drop size. Therefore, the total amount of splashing decreases. However, as viscosity of the liquid increases, the splashing material increases due to the changes in the splashed material from droplet shape into filament form. The height of liquid inside the converter, depending on the relative height of heavy phase and light phase, is an important parameter regarding splashing. As the relative height of heavy phase to light phase increases the splashing will decrease. The tuyere blockage will cause the pressure in the inlet manifold to increase; and in real cases will increase the splashing. Finally, we have development a model based on dimensional analysis to relate the above parameters in order to calculate the amount of splashed material.

Jan 1, 2007

By R. Grimard, M. Gamache, L. -P. Bigras, P. Cohen

This paper describes a real-time fleet management system for an undergroun mine. Dispatching, routing and scheduling are handled simultaneously, taking into account the mine status, operational constraints and vehicle location information. Each assignment decision takes into account the traffic on the road segments of the mine network, whether road segments are bi-directional or uni-directional, and ensures that each LHD (load-haul-dump) vehicle arrives at loading and dumping points with the correct orientation. Such a system can be used either as a simulation tool for strategic planning or as a real-time managing and optimizing system for operations. In the simulation mode, the system can accurately estimate the impact on productivity of decisions such as the development of waiting areas (bays, sidings), or the addition (elimination) of vehicles to the fleet in operation. When used for real-time dispatching, routing and scheduling of vehicles, the system can optimize production with respect to various assignment criteria such as cycle-time minimization or deviation from a target production plan.

Jan 1, 2004

By J. H. McKibbon

THE metallurgical industry has purchased more than sixty per cent of the industrial gas cleaning equipment installed in Canada. This includes cyclonic collectors, scrubbers, cloth filters and Cottrell Precipitators. These are the principal types of equipment which are used commercially for the cleaning of gases which result from the processing of iron, nickel, copper, lead, zinc, gold, gypsum and aluminum ores. The recovered dust, which usually contains metal values, is returned to the process. The cost of the equipment is thus economically justified. This is in contrast to other industries, such as those involving steam power generation, asbestos, cement and lime production, where, though dust collection equipment is extensively used, it is installed primarily for nuisance abatement. Communities are becoming more and more conscious of air pollution, new and more stringent legislation is being enacted, and, for other than economic reasons the smelting industry will eventually be required to install more efficient gas cleaning equipment. This paper

Jan 1, 1962

By Frederick Biery

Outline ? Project Challenges ? Results from 100 recent projects ? What factors are driving the best and worst projects ? A look at recent mining projects ? Conclusions

May 1, 2009

By Cameron J. Clayton

Cumberland Resources Ltd. is currently planning to develop the Meadowbank Gold Project located some 70 km north of Baker Lake, Nunavut in the eastern Canadian Arctic region. The Meadowbank Gold Project currently consists of up to 6 main gold bearing deposits within relatively close proximity to one another which are planned to be mined primarily as a truck-and-shovel open pit operation and using conventional gold milling and extraction. The mining plan indicates that approximately 20 million tonnes of ore will be mined over a mine life of 8 to 10 years. The operation will generate approximately 160 million tonnes of mine waste rock and about 20 million tonnes of tailings. The site is located in an area of continuous permafrost with mean annual average air temperature of -11 °C and average annual precipitation in the range of 100 to 200 mm. Lakes cover a large portion of the site, including some of the ore deposits. The location of the site, and the physical environment, pose challenges to development. This paper presents some of the designs considered to effectively manage and utilize the waste products of mining at the project.

May 1, 2004

By A. Ismail

"The paper takes its material from three peat mining and power project feasibility studies sponsored by CANMET and conducted by Montreal Engineering Company Ltd. in the years 1976 to 1980. The role which peat may play in the Canadian energy prospectus is outlined, estimated and measured fuel peat resources are tabulated, and the economic and technical feasibility of mining peat for power generation is reviewed Recommendations are made for future work, and construction and disbursement schedules are developed for a combined peat mining and power generation project. The relationship between the mining of moss and fuel peat is discussed.IntroductionWhereas moss peat has long been produced in Canada, and exported for horticultural use , the underlying fuel peat has received little attention until fairly recently.In the seventies, however, the deepening oil crisis spurred Canadian interest in Irish, Finnish and Russian experiences in the utilization of fuel peat. Among others, Energy, Mines and Resources Canada had long been alive to the possibilities which indigenous peat offers, and in 1976 the Canada Centre for Mineral and Energy Technology (CANMET encouraged a proposal from Monenco to carry out a preliminary study and submit a report on the "" Assessment of Canadian Peat as an Alternative Fuel for Power Generation"". The report was submitted in April 1977. This was the first of a series of studies, and the authors of this paper were involved in its preparation.The escalating price of oil and the increasing problem of relying on its availability have combined to make alternative fuels more attractive. Peat, like other fuels previously uneconomic because oil was cheap, is now progressively gaining in viability. In addition to these factors, the utilization of peat has the following advantages: improvement in the country's balance of payments, by virtue of burning an indigenous fuel;creation of local employment for the mining of peat; improvement in land utilization;peat is a relatively clean-burning fuel, with low sulphur and ash contents."

Jan 1, 1980

By H. A. Kishawy, S. Kannan, M. Balazinski

Metal Matrix Composites (MMCs) are new generation engineering materials that possess superior physical and mechanical properties compared to nonreinforced alloys. However, the presence of abrasive ceramic reinforcements in the ductile matrix causes severe tool wear and premature tool failure. Flank wear was found to be the dominant wear mode while the main wear mechanism was abrasion. Analysis of the cutting tools using scanning electron microscopy has shown that both two body and three body abrasion are operational during machining MMCs. A methodology for predicting the tool flank wear progression during bar turning ofMMCs was presented in an earlier paper [1]. In the proposed model, the wear volume due to two body and three body abrasion mechanisms was formulated. Then, the flank wear rate was quantified by considering the tool geometry in 3D turning. The main objective of this paper is to investigate the contribution of two body and three body abrasion towards the tool wear volume during cutting MMCs.

Jan 1, 2006

By Chris G. Dobson

Introduction The Britannia mine is at Britannia Beach, on Howe sound, approximately thirty miles from Vancouver. The first claims were staked in 1898, and a local company was formed at that time to develop them. In 1904, Mr. Grant B. Schley became actively interested in the property and in the following year the Britannia Mining and Smelting Company, Limited, was incorporated to operate it. This Company was taken over a few years later by the Howe Sound Company, Limited. The mine comprises five more or less separate ore-bodies, which have produced approximately 20,000,000 tons of ore to date. The East Bluff ore-body, with which the present paper deals, is well suited to large-scale mining by means of carefully placed powder blasts. It covers approximately an acre and lies in the slate footwall, in a bay produced by a fault. The hanging-wall side, on the west, forms the face of the Bluff glory-hole, which extends to the 1,200 level. A portion of this ore was available for breaking into this old glory-hole, below which four bulldoze chambers could quickly be built. Mining of this block is complicated by a very soft footwall, which 'runs' badly when broken. In stoping, care is taken to guard against the hazard of dilution by deliberately leaving a small portion of ore on the footwall. Some of this will undoubtedly be lost, but it is hoped to recover a fair amount of it after the major drawing is completed. The deposit occurs in a greenstone which has been highly silicified following brecciation. The chief minerals are chalcopyrite, sphalerite, and pyrite. Concentrates of copper, zinc, and pyrite are made at the mill. The average grade of ore runs 0.7 per cent copper, 1.5 per cent zinc, and 0.03 oz. gold per ton. The rock, which is practically a chert, is extremely hard, but shatters well. Both in stoping and drifting, holes must be closely spaced and powder used generously. Development When development work started in the East Bluff, there were no raises and only one drift on each level in this section of the mine. After blocking out the ore by thorough diamond drilling, a production of two thousand tons per day was set as a goal. To obtain this tonnage from so small an area required a great deal of carefully planned and well timed development work.

Jan 1, 1935

By Paolo Toscano, Dave Hall

"This paper discusses the project history, process design and layout of the Rainy River Gold Project mill. The circuit consists of a 55 x 83 primary crusher, 15 MW SAG mill and 15 MW ball mill. Both mills are twin pinion with LSS and VFD drives. A pebble crusher is located in the process plant with bypass and stockpile options. Gravity concentration followed by 30 hours of leach residence, carousel CIP, carbon recovery, cyanide destruction and tails disposal in a 1,428 hectare tailings management area (TMA).The Rainy River Gold Project is located approximately 65 km northwest of Fort Frances in north western Ontario. The project is scheduled to be commissioned and reach commercial production in mid-2017. Expected cost is $US877M and is comprised of an open pit mine, process plant, tailings management area and supporting infrastructure. The process plant is designed to produce gold/silver Dore’ bars.The project has been developed on the following timeline:• 1967 – First exploration• 1994 – 17 zone discovered• 2004 – 433 Zone discovered• 2005 – Rainy River Resources Ltd. purchases property • 2006 - ODM zone discovered• 2007 - Cap Zone discovered• 2008 - First NI-43-101 Resource completed• 2012 - PEA completed & Intrepid Zone discovered• 2013 - New Gold acquires Rainy River Resources• 2014 - Updated feasibility study completed & Environmental Assessment report submitted• 2015 - Detailed Engineering >95% complete, EA approved and construction commencesThe property is accessed by provincial highway 600 and is within 17 km of 230 kV power line and railway sidings. Key project criteria are summarized as follows:"

Jan 1, 2016

By I. C. Brown

Introduction Many tables of nomenclature for igneous rocks have been introduced from time to time, and each has its strong proponents. As a result, any discussion of igneous? rocks is apt to prove confusing unless the names used for these rocks are defined. This ?became so obvious to a discussion group, formed by the members of the Geological Survey of Canada in 1948, that an attempt was made to establish a scheme of nomenclature that could be used by any member mapping anywhere in Canada. The writer was asked to co-ordinate the ideas presented by individuals in the discussion group, to arrange them in tabular form, and, later, to distribute copies of the resultant table to Canadian universities, provincial geological surveys, and some other geological discussion groups. Many useful suggestions and criticisms were received, were studied ?by members? of the original group, and, so far as practicable, were incorporated in the scheme of nomenclature. The result is the table presented here. This nomenclature of igneous rocks is at present being used by most members of the Geological Survey of Canada who are working with igneous rocks, and by some Canadian universities. We hope it will be found useful and be more widely accepted. With this idea in mind, certain principles were adopted in drawing up the nomenclature.

Jan 1, 1952

By J. C. Hampton, L. A. Matzar, C. R. Gamwell

In geomechanics, conducting uniaxial or triaxial compression tests require samples to be prepared to a certain length-to-diameter ratio. This ratio is typically defined as 2:1 (length to diameter) and is accepted as a common standard for all materials on which mechanical properties testing is performed. Variations in sample length can cause changes in measured strength properties across multiple material types, such as cement, rock, or soil. Within the oil and gas industry, it is not uncommon to receive samples for technical services work that are slightly under or exactly the length requirement before surface grinding and sample preparation. Many of these samples are discarded from uniaxial and triaxial compression tests and used in another manner; therefore, it is necessary to study the length-to-diameter ratio in efforts to understand the limits and validity of testing samples that are slightly out of the 2:1 ratio. This paper discusses uniaxial compression tests performed using Berea sandstone and a standard cement mixture of 2.54-cm diameter to study changes in rock strength and properties. Compressive strength for each lengthto- diameter ratio over a range of 0.5:1 to 2.2:1 was measured. The investigation was extended to study near-end effects, where the sample length is near, but not exactly twice the diameter. It was discovered that the cement samples conformed reasonably well to the suggested ASTM correction factors. The sandstone did not conform to the correction factors and further analysis is required to develop a correction factor unique to the material. Near end effects, in both the cement and Berea, were found to increase compressive strengths, especially when the L/D of the samples was increased slightly over a 2:1 L/D.

Jan 1, 2015

By M. H. Allan

SASKATCHEWAN POWER CORPORATION is a Provincial Crown Corporation responsible for the production transmission and distribution of electric power and natural gas in the Province of Saskatchewan. Through the electric power responsibility, we became interested in the coal reserves in Saskatchewan, which, although still somewhat of an "orphan fuel" in the early and mid 1950's, gave the promise of providing a low-cost source of energy for electric generation. Coal in Saskatchewan, a lignite with an "as-received" heating value of from 5000 to 6500 Btu's per lb and up to 40% moisture, was first recorded in 1853 . By the end of the 19th century, many small mines were in operation in the Estevan, Coronach and Shaunavon areas supplying local inhabitants with a cheap source of heat. These small mines, some of them prosperous, some of them not, continued operation right up to the late 1940's, when oil replaced coal in the market place. The year 1930, however, saw the introduction of the new technique of strip mining in the Estevan area. This technique revolutionized coal mining. It was now possible to use large machinery to uncover the coal and cast the overburden to one side instead of burrowing through thin seams of coal varying from 2 to 10 feet thick. The overburden cast aside by these large mechanical shovels, or later draglines, created heaps of spoil which at that time, during the depression, were a sure sign of prosperity and the welcome news that people had jobs. By the late 1940's, coal production had dropped off, but the spoil piles remained and were now labelled by some as "scars on the landscape", even though there had been some natural succession of grasses. In addition, some people had planted trees in experimental plots and even some aerial seeding had been done.

Jan 1, 1978

By J. Andrew Cornier, Mike Cooper

"Upon successful completion of the AG/SAG Mill project (Cooper et al., 2001) the Brunswick Mine concentrator was configured with single line processing through the AG/SAG mill, followed by two parallel ball mill and flotation circuits. The Stage Grinding project was undertaken to utilize a pre-flotation stage on the AG/SAG mill primary cyclone overflow and simplify the flowsheet by consolidating the two ball mill and flotation circuits, resulting in single line processing fi-om AG/SAG mill to final concentrate. Concurrently, the reclaim water supply capacity was increased to enable flotation cleaning at lower percent solids.Benefits from the Stage Grinding project include revenue enhancement from increased zinc grade and recovery combined with additional lead recovery. Further benefits included a reduction in the number of process pumps, reduction in loss associated with spillage to sumps and process simplification through efficient use of equipment layout.The Stage Grinding project was implemented in six phases over a period of seven months in 2000. Each phase was commissioned during scheduled concentrator shopdays with minimal additional downtime required. One year after project approval the Stage Grinding project was completed at a total cost of $1 1.8 million.INTRODUCTIONThe Noranda Inc. Brunswick Mine, located near Bathurst, New Brunswick, is one of the world’s largest leadzinc mines. Milling of ore began in 1964 from the No. 12 orebody, with an expansion in 1966 to accommodate ore fkom the No. 6 open pit located several kilometers away. In 1980 the pit was exhausted and the concentrator rationalized to accept a design feed rate of 10,500 tomes per day from the No. 12 mine. In excess of 100 million tomes have been milled to date, representing over three-quarters of the known reserve. The concentrator employs differential froth flotation to produce lead, zinc, copper and leauzinc bulk concentrates. The ore is massive sulphide, with approximately 20% valuable minerals, 60% pyrite and 20% silicates."

Jan 1, 2002