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By Antonio Fontana

"Environmental problems encountered with the use of diesel equipment in underground mining operations are discussed. The concept and procedure o implementing the Health Effects Index equation as a means of quantitatively assessing an underground working environment is outlined and sample calculations are present ed. Advantages and disadvantages of utilizing this method are also discussed.IntroductionWith the introduction of diesel-powered mining equipment in the 1960s there arose several question s for the environmental engineer to consider. These included: 1. What are the constituents of diesel exhaust and how can they be detected and evaluated?2. What are the toxicities and long-term health effects of these constituents?3. What is the ventilating volume required to maintain the concentration of these constituents below toxic levels?Diesel engines are a class of reciprocating, internal combustion engines in which relatively high compression ratios are used to generate high air-charge temperatures, which cause ignition of fuel to occur spontaneously. Ideally, perfect combustion of the fuel would produce an exhaust consisting solely of nitrogen (N2), water (H2O), carbon dioxide (CO2) and oxygen (O2). However, because no combustion process is perfect, relatively small quantities of imperfect-combustion products, or pollutants, are also generated. These include hydrocarbons (HC), carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO2), carbon (C) or soot, and sulphur dioxide (SO2).Currently, the Regulations for Mines and Mining Plants, made under the Occupational Health and Safety Act (Section 176), stipulate that weekly tests shall be made to determine the carbon monoxide (CO) concentration in the undiluted exhaust and at the operator's position, and the nitrogent dioxide (NO2) concentration at the operator's position. Also, the aldehyde (as HCHO) concentration in the atmosphere, at the operator's position, is to be measured at least every three months. Threshold limit values (TLVs) have been established for each of the three combustion products, and each is regarded as a separate entity. Consequently, this does not allow for consideration of interactions and possible synergistic effects between the various exhaust components."

Jan 1, 1982

By David J. Morrison

Scarcity of truck tyres, increasing cost and decreasing availability of labour, increases in fuel costs and project budget blowouts have changed the paradigm behind mining equipment selections. The cycle of commodity changes have occurred in parallel with the increasing maturity of continuous mining machinery, mobile in-pit crushing systems and very large scale conveyor belt systems. This paper will consider the merits of operating continuous materials handling systems, mobile in pit crushing systems, relocatable crushing systems, relocatable conveyor systems and automated waste handling systems in place of the more conventional approach of truck haulage.

May 1, 2007

By C. Dragusanu, J. Sims, J. Connolly

Based on a statistical analysis of the categorical and numerical data from the established geological model, a geochemical classification of mineralization has been shown to be objective in nature and correlated to the envisioned metal extraction process. Multivariate chemical classification has the potential to discriminate within a combined response from different types of alteration and metal abundances. Distinct domains of chemical response determined by clustering analysis were used as a validating criterion for a geologically driven metallurgical testing program. The groups established are spatially linked to the geological process responsible for their genesis, providing clarity in geometallurgical and resource modeling.

Jan 1, 2011

By W. F. Moore

"In January 1981, Quintette Coal Limited (QCL) signed a 2a-year coking coal sales agreement with the Japanese Steel Industry which was followed by the commencement of mining operations in October 1982 and preparation plant operation in November 1983. During the mine 's startup, the town of Tumbler Ridge, the Anzac rail spur line, coal port facilities at Ridley Island plus numerous related elements of infrastructure were completed to support QCL and the neighbouring Bullmose operation in northeastern British Columbia. QCL's annual product coking coal levels have accelerated from 2.9 to 5.2 Mt between 1984 and 1986 with related increases in total mined volume from 14.8 to 41.0 M BCM between 1983 and 1986. This paper presents an overview of QCL 's current operation and related infrastructure. Development BackgroundDuring the 1970s, the Japanese Steel Industry (JSI) was forecasting a steady and significant growth in its steel production. By 1980 they were expecting crude steel production to increase from about 105 Mt in 1980 to 125 Mt by 1985 and almost 140 Mt by 1990.Discussions between Quintette Coal Limited (QCL) and the JSI for the development of the QCL project began in the 1970s and continued over a period of several years. During that time detailed and regular meetings took place, at which technical and commercial presentations were made to the JSI. The geology of the project area and the alternative mining methods and sequences were studied in detail. The new rail line which would connect the mine to tidewater was a critical factor and received particular attention. Alternate routes for the rail line from Tumbler Ridge to Prince George were the subject of much detailed study and discussions. The Anzac route was chosen in the best long-term interest of the northeast area development, after careful consideration and advice from the Japanese side.The new bulk coal terminal on Ridley Island at Prince Rupert was also a key factor and completed the development of an independent and new major coal field to supply the JSI. The QCL project and the development of the northeast area of British Columbia was a major strategical initiative of the JSI. It provided Japan with an important new coal field which was both self-sufficient and distinct from the traditional Japanese coal field resources in southern Canada, Australia, and the United States."

Jan 1, 1988

By J. E. Shigley

The gemological properties that allow natural emeralds and blue sapphires to be distinguished from other gemstones are summarized in this paper. A variety of synthetic and laboratory-treated emeralds and blue sapphires are also encountered in the jewelry industry today. Gemologists distinguish these latter materials from their natural counterparts based primarily upon features seen with magnification, such as inclusions and/or growth zoning. In some cases, however, these observations and standard gem-testing methods are insufficient, and the use of non-destructive analytical methods, such as optical spectroscopy and chemical analysis, are required for positive identification. The commercial value of synthetic and treated gems are much less, and can be insignificant in comparison to that of an important untreated natural gemstone. Identification of synthetic and treated gem material is essential to maintaining integrity in the jewelry industry. Loss of consumer confidence in the gemstones sold at the jewelry counter could have a negative impact on the exploration and mining of natural emerald and blue sapphire.

Jan 1, 1998

By K. J. Mintz

Conveyor belts installed in an underground mine can be a potential source of a major fire, thus the need for fife-retardant belting. A Canadian Standard, CAN/CSA-M422-M87, incorporating a small-scale flame test, a drum-friction test, a flame propagation test and an electrical surface-resistance test, has been developed to meet the varied needs of the mining industry. It is recommended that mines use Types A and B belting described in that Standard, because they will have passed the large-scale flame propagation test, rather than Type C, which does not require that test. Belting that has been approved by the U.S.A. Mine Safety and Health Administration (MSHA) may be much less fire-retardant than any Canadian approved belting.

Jan 1, 1992

By E. Gaucher, D. C. Gagnon

"The paper refers to methods and concepts used in the computer treatment of banks of geophysical, geochemical and geological data, relating to the exploration of massive sulphides. In particular, a data bank of 400 drill holes on independent conductors can be used to calculate probability levels of intersecting a certain quantity of sulphides according to the characteristics of the conductor. Inversely one can, using the data bank and some cost assumptions, simulate and optimize the cost of intersecting a certain quantity of sulphides by selecting drill targets among conductors according to conductivity, magnetism or gravity. Problems of noise, inherent in any simulation, are illustrated in this paper by the results of a study of the nomenclature of volcanic rocks of 27 drill holes by forty geologists. Compilations of data banks are long and timeconsuming, and it would help to standardize to allow exchange of data. We believe that such efforts may result in the discovery of more mineral deposits and at a lower cost. The present study is supported jointly by SOQUEM The New Jersey Zinc Co. and Cominco Ltd."

Jan 1, 1973

By Donald F. MacDonald

THE cement plant nearest to Nova Scotia is not far from Montreal. Cement is a heavy product which, because of its relatively low value, cannot stand a high freight charge without unduly enhancing its cost. This is one reason why cement costs are high in Nova Scotia. The regular retail price per bag (8772 lb.) in Antigonish is 85 cents, which would be $3.40 per Canadian barrel of 350 pounds, or $3.65 per American barrel of 376 pounds.It is said that the lowest wholesale price in Halifax is 65 cents per sack, which would be $2.60 per Canadian barrel or about $2.80 per American barrel. According to U.S. Bureau of Mines statistics, the average factory price for cement in 1937 was $1.48 per American barrel, which is practically the same as the value per barrel indicated in Dominion statistics for the Canadian output during that year. The difference between $3.40 and $1.48 is $1.92. It is evident that the average user of cement in the Mari-times pays a stiff premium because Maritime cement raw materials have not been developed. Rock-wool, the manufacture of which is rapidly increasing in Ontario and the United States, is much needed for building insulation in the cold climate of Nova Scotia.

Jan 1, 1939

By M. Lebeuf, A. Dumais, C. Farsangi, N. Singh

The Nunavik Nickel project began ramp-up of a new ore body (Expo) in November 2014. This new deposit is significantly more competent than the previous ore type milled (i.e., the plant moved from a feed with a BWI of 12.2 kWh/t to predominantly material with a BWI of 19.6 kWh/t). Despite circuit changes made in advance of the Expo ore ramp-up (grinding media size, mill loading/power draw, and cyclone configuration) the throughput of the plant was bottlenecked at 90% of targeted throughput with multiple stoppages to grind-out the primary mill due to excessive circulating loads. During this time, the secondary milling circuit was under-utilised: therefore the focus for debottlenecking plant production became increasing the product size of primary milling. Given the scope of changes already made to the circuit, it was decided to test the mill in open circuit. The milling changes were modelled using the Molycop Tools package to identify potential problems. In the modelling and plant trial it was apparent that the ball size in the secondary grinding circuit was inadequate, resulting in pebbling. The power draw of the secondary mill was brought up to minimize pebbling and the average ball size was increased. The switch to open circuit primary milling permitted a significant augmentation in plant tonnage. While the overall grinding efficiency decreased using the open circuit configuration, the ability to increase throughput made it the clear operating choice.

Jan 1, 2016

By Richardson A. H.

"IntroductionSafety and training in the mineral industry will always be issues that are hotly debated and discussed.The nature of the mining industry, where people and equipment work in close quarters deep below the earth's surface, attracts a great deal of public attention and concern, especially in the areas of safety and related training activities. This concern has been carried over into the mineral processingsector which is, of course, a vital part of the mining industry.It is therefore imperative that mining people closely examine the policies, procedures and programs presently in place to determine if they meet the needs of the industry and its employees. Everyone stands to benefit: the companies, employees and the mineral industry as an important segment of the Canadian economy.Phrases such as ""Safety First"", ""Safety is Number One"", have a role to play in industrial safety programs but in reality are a shallow approach to the magnitude of the challenge. An industry must produce its products in a cost-effective way, with good employee relations. None of these objectives can be successfully achieved unless accompanied by good safety performance. Accidents both on and off the job result in very poor efficiency, high costs and poor employee relations.This chapter, Safety and Training, outlines those major areas that the author believes are necessary components for an industrial safety, health and training program, but are not all inclusive. More will surely be added as additional problem areas requiring attention are identified. The major sections discussed are: Development and Implementation of a Safety Program; Occupational Health; Training; and Audit Procedures.The author has drawn on his experience as both a mill superintendent, mine manager and superintendent of safety, health and training. The approach developed at loco Metals Manitoba Division is frequently used in this paper with examples and excerpts to better illustrate the subject, but does not represent the full scope of programs in place in the Division."

Jan 1, 1989

By O. P. Garg

Based on improved methods of collection and analysis of geotechnical data, slope angles have been steepened in some mines of the Iron Ore Company of Canada at Schefferville, Quebec. This paper describes the slope design case history for Fleming NO.3 mine and illustrates the application of modern techniques. The new design has resulted in significant financial savings due to a reduction in required waste stripping.

Jan 1, 1978

By Gaston Gendreau

CETTE PRÉSENTATION traitera des différentes phases des opérations de la mine du Mont-Wright depuis ses débuts jusqu'à présent. A une brève description de la géologie du gisement, suivra un exposé des méthodes d'exploitation de la mine et du genre d'équipement utilize.

Jan 1, 1977

By Yu. V. Ponomarenko, A. I. Meka, P. A. Witherspoon, Yu. I. Volkov, J. E. Gale

"The mining of iron ore in the Kursk Magnetic Anomaly (KMA) region of the U.S.S.R. is done mostly by the open-cut method. An assembly of open pits capable of producing about 100 million tons of ore per year makes KMA the largest iron ore field in the world. Three gigantic open pits are currently in operation: Lebedinsky, Mikhailovsky and Stoilensky. These pits are as large as 13 km2 on the surface and as deep as 230 m. The mining operations are constantly faced with the problem of flooding from aquifers that overlie the orebodies; the magnitude of the problem is evident from the fact that the present groundwater inflow to these three pits is about 110 million mt /yr.Under such conditions, safe operations and pit wall stability are of great importance, and this has been accomplished very effectively by the appropriate use of seepage barriers and drainage systems. At KMA, the most important items used in the system of groundwater control are standard pumping wells, raise wells that drain into a 20 km to 30 km long underground drift located just outside the perimeter of the pit, horizontal wells driven through the pit walls, and horizontal drains. This paper describes the mining and engineering technology that have been developed at KMA to control the groundwater systems and protect the mines from flooding."

Jan 1, 1992

Agenda ? Where?s Victor ? What work was done to get approval to spend $982m ? a brief history ? Some project facts ? The triple bottom-line accomplishments to date ? Construction A Brief History of Victor ? 1960?s ? first sampling in area ? 1980?s ? stream samples and Victor kimberlite discovered ? 1990?s ? test / bulk samples ? 1999 / 2000 ? large bulk samples ? 2000 / 2003 ? technical evaluation through to Feasibility Study, permitting process

May 1, 2006

By D. Laguitton

The basic chemistry of a1•senic related to its dissolution and subsequent precipitation in gold-mine waste waters is discussed. The lime addition methods provides the most economic treatment of arsenical slurries, but requires a careful control of the oxidation of Asm into Asv, of the pH (>12) and the filtration of the precipitate. If arsenic levels below 0.5 mg/ l are required, a modification of the method by phosphate addition must be considered.

Jan 1, 1976

By F. E. Millett

The following notes deal chiefly with changes from steam to electric drives, or, in the case of the Bellevue pumps, from air to electric. Where electric power can be purchased or generated cheaply it can be used to advantage and is generally more economical than steam, especially in places remote from the central power-plant. Nothing could be more simple than the operation of electrical gear. It does not require a competent engineer constantly on the alert, oiling and watching bearings, and maintenance is at a minimum. The ease with which the current is transmitted from its source to where it must do its work is one of its greatest advantages. Transmission losses are very low. Generally speaking, the smaller the plant the lower the loss and 90 per cent, and better, efficiency is easily attained. In and around Bellevue 2300-volt, three-phase, is the standard distributing pressure; our power requirements and the distances transmitted, for the present, do not require more than this. Most of the heavier motors are 2300-volt .machines, which eliminates the cost and possible troubles of step-down transformers, and makes for a cheaper and less bulky motor. This applies to two fan, two hoist, and two compressor motors, the smallest being 75 and the largest 520 horse power. The standard pressure on power lines to all inside pumps is 550 volts, and 220 volts is general for the the tipple. While 110 volts is used for house and office lighting service, it is not economical around and in the mine. No matter what kind of device is used to lock and protect the lamps, they are invariably missing.

Jan 1, 1926

By Rodolfo Zanella

Au/TiO2 catalysts were prepared by deposition-precipitation using NaOH (DPN) (~3 wt % Au) and urea (DPU) (~8 wt % Au), and calcined at various temperatures between 100 and 400 °C. They were characterized by UV-Visible, XANES, EXAFS and TEM. Their activity were tested in the reaction of CO oxidation at 5°C. After preparation, the gold species are in the oxidic state III. They begin to transform into metallic gold under air at ~100 °C for DPN and ~150 °C for DPU. At 200 °C, all the gold is metallic for the two preparation methods. The particle size increases from 1.5 to 3.5 nm with the calcination temperature. The catalytic activity for CO oxidation increases with the percentage of metallic gold, and it is maximum at 200°C for both types of samples. The activities (per mole of Au) are the same for the two types of catalysts. At higher temperatures, the catalytic activity drops. The decrease of activity is mainly due to a change of particle shape with the calcination temperature rather than to the increase of the particle size. At a calcination temperature of 200°C, the particles present small facets with rounded parts, and their outer surface contains a large proportion of low coordinated sites (steps and corners) while at high temperature of calcination, they are truncated octahedra with smooth facets.

Oct 1, 2003

By J. Wickens

"Campbell Mine is dedicated to quality management in the form of a Continuous Improvement (CI) Operating Philosophy. This paper discusses that philosophy, why and how it is being implemented in the milling facility, and some of the challenges experienced to date. Examples of mill CI team projects and results are described. This paper describes practical experiences for those who are considering or are in the process of adopting a CI operating Philosophy.INTRODUCTIONCampbell Mine is 100% owned and operated by Placer Dome Canada Ltd. The mine is located in Balmertown, Ontario approximately 300 km northeast of Winnipeg, Manitoba. Campbell Mine has produced over s,000,000 ounces of gold since commencing operation in 1949. The operation is profitable and continues to be a major contributor to the gold production of Placer Dome Inc.At Campbell Mine, the concept of Continuous Improvement (CI) is being implemented to make further improvements to safety, quality, productivity, and subsequently profits. CI is not a ""program"". It is a way of doing business that concentrates on improving the system rather than finding fault and being resigned to the status quo.CI focuses on involving all employees in the decision making process and tapping their expertise to improve every facet of the business. In the past, many solutions were simple ""band-aid"" fixes treating the symptom, only to see the problem resurface again. With CI, solutions endeavour to address the root cause of problems and eliminate them permanently. Another primary goal is to eliminate unilateral decisions that benefit a small group but have a negative effect on the whole system."

Jan 1, 1995

By J. P. Grieco, F. W. Grieco

"Manufacturing of Jaw CrushersOriginIn 1858 Eli Whitney Blake invented the first successful mechanical rock breaker-the Blake-type jaw crusher. Blake adapted a mechanical principal, the powerful toggle linkage system used to transform rotating motion and energy into oscillating mot ion and tremendous compressive forces. Today these same principals apply and the basic Blake-type jaw crusher is one of the leading machines of its class for heavy duty primary crushing service.In 1881 Philetus W. Gates patented a design for a crusher, the forerunner of the modern gyratory crusher which dominated the field from the late 1800s to the early 1900s. In 1910 the largest gyratory crushers built had 48-inch openings. However, about this time the jaw crusher came to life when the Power and Mining Machinery Co. built an even larger sized opening crusher-a giant 84-inch by 60-inch jaw crusher for a trap rock quarry in Pennsylvania. A 24-inch gyratory crusher became the ideal sized secondary machine for this size jaw. From that time on jaw crushers were looked on favourably as primary breakers and lines were brought up to date to parallel the already developed gyratory lines.FunctionMost heavy duty Blake-type jaw crushers work basically the same way. They are ruggedly designed and capable of crushing material in some cases in excess of 80, 000 p.s.i. compressive strength. They are very simple machines with few moving part s and, with the exception of replacement of renewable parts, are relatively maintenance free. It is quite common to have these machines in product ion for 20 to 30 years. The following will de scribe how these machines work. Large-diameter high-inertia flywheels which are connected to the main eccentric shaft, rotate inside a connecting rod type mechanism called a Pitman. It transforms rotating motion into vertical oscillating motion. This vertical motion is in turn transformed into reciprocating mot ion by means of a system of 2 toggles, each connected to the Pitman. The rear toggle is connected to the fixed rear head, and the front toggle is connected to the swing jaw which is hinged at the top of the crusher. With each rotation of the eccentric shaft the swing jaw opens and closes on rock which is fed into the crusher chamber, crushing the rock in a series of bites. These bites, or strokes as the y are called, usually vary between 1/2 inch to 1 1/2 inch at speeds of 120 to 200 strokes per minute. The reduction ratio of feed input to discharge is usually about 8 to I. Output capacities can vary from 100 tons/hour to 1200 tons/hour depending on the size of machine and its discharge opening. Horsepower requirements can vary from 75 hp to 400 hp.The entire crusher chamber is lined with replaceable 14070 manganese steel liner plates. This material is ideally suited for the job since it hardens as it wears during crusher operation. Manganese is also used in the high wear areas at each end of the toggle plates."

Jan 1, 1985

By J. P. Grieco, F. W. Grieco

"Manufacturing of Jaw CrushersOriginIn 1858 Eli Whitney Blake invented the first successful mechanical rock breaker-the Blake-type jaw crusher. Blake adapted a mechanical principal, the powerful toggle linkage system used to transform rotating motion and energy into oscillating mot ion and tremendous compressive forces. Today these same principals apply and the basic Blake-type jaw crusher is one of the leading machines of its class for heavy duty primary crushing service.In 1881 Philetus W. Gates patented a design for a crusher, the forerunner of the modern gyratory crusher which dominated the field from the late 1800s to the early 1900s. In 1910 the largest gyratory crushers built had 48-inch openings. However, about this time the jaw crusher came to life when the Power and Mining Machinery Co. built an even larger sized opening crusher-a giant 84-inch by 60-inch jaw crusher for a trap rock quarry in Pennsylvania. A 24-inch gyratory crusher became the ideal sized secondary machine for this size jaw. From that time on jaw crushers were looked on favourably as primary breakers and lines were brought up to date to parallel the already developed gyratory lines.FunctionMost heavy duty Blake-type jaw crushers work basically the same way. They are ruggedly designed and capable of crushing material in some cases in excess of 80, 000 p.s.i. compressive strength. They are very simple machines with few moving part s and, with the exception of replacement of renewable parts, are relatively maintenance free. It is quite common to have these machines in product ion for 20 to 30 years. The following will de scribe how these machines work. Large-diameter high-inertia flywheels which are connected to the main eccentric shaft, rotate inside a connecting rod type mechanism called a Pitman. It transforms rotating motion into vertical oscillating motion. This vertical motion is in turn transformed into reciprocating mot ion by means of a system of 2 toggles, each connected to the Pitman. The rear toggle is connected to the fixed rear head, and the front toggle is connected to the swing jaw which is hinged at the top of the crusher. With each rotation of the eccentric shaft the swing jaw opens and closes on rock which is fed into the crusher chamber, crushing the rock in a series of bites. These bites, or strokes as the y are called, usually vary between 1/2 inch to 1 1/2 inch at speeds of 120 to 200 strokes per minute. The reduction ratio of feed input to discharge is usually about 8 to I. Output capacities can vary from 100 tons/hour to 1200 tons/hour depending on the size of machine and its discharge opening. Horsepower requirements can vary from 75 hp to 400 hp.The entire crusher chamber is lined with replaceable 14070 manganese steel liner plates. This material is ideally suited for the job since it hardens as it wears during crusher operation. Manganese is also used in the high wear areas at each end of the toggle plates."

Jan 1, 1985