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By A. E. Dyment

In formulating an explosive for any specific set of conditions, various factors must be taken into consideration. Is it to be subjected to water or moisture? .If so, it must be designed to have an inherent ability to resist water. Is it to be used in confined spaces underground, where ventilation is limited? If it is, it must possess qualities enabling it to form, upon explosion, the minimum quantity of noxious gases, such as carbon monoxide or oxides of nitrogen. Is it for use where low temperatures may possibly prevail? If so, it must be capable of resisting such temperatures without freezing. Is it for use where dust or inflammable gases may be present? If it is, then it must be so formulated as to produce, upon detonation, a flame of the lowest possible temperature and the shortest possible duration, in order to lessen the chance of ignition of such gas or dust. This is actually the essential property of a permitted explosive, and it is undoubtedly the most important characteristic of an explosive which is to be used in gassy or closed-light mines. This being the quality that distinguishes permitted explosives from other types, it is interesting to investigate the ways and means by which the low-flame-temperature characteristic is obtained . Generally speaking, such explosives are so designed as to contain comparatively small quantities of nitroglycerin and relatively large quantities of the strength-producing salt, ammonium nitrate. This ingredient does not develop as high a temperature upon explosion as does nitroglycerin, so its presence, in large measure, in place of nitroglycerin results in an explosive which has an inherent low-flame-temperature characteristic, as opposed to one which is .made up largely of nitroglycerin, which would ordinarily be in the high-flame-temperature class. Additions are also made of flame-quenching salts such as sodium chloride, ammonium chloride, and up to a certain limiting percentage of sodium nitrate. These salts, with the exception of the last, do not ordinarily take an active part in the explosive reaction, being present primarily to absorb heat liberated by the reacting ingredients.

Jan 1, 1947

By Euler De Souza, Kyle Penner

"Booster fans play an important role in assisting main fans by boosting the air pressure of the ventilation air passing through it. The correct placement of underground booster fans in a mine is a critical decision since it not only influences the mine’s operational capacity in terms of costs and efficiency, but also affects safety and environmental conditions. There are many booster fan installations around mines that are inappropriate, in some cases resulting in system failure (fan stall) or in a major negative impact on mine production. Inadequate booster fan placement has resulted, in some cases, in extensive air leakage which has compromised the economics of the operation and, in other cases, in recirculation of contaminants which has seriously compromised safety. This paper provides guidelines for proper design and siting of booster fans underground, to not only achieve an economic ventilation system but to create safe work conditions and efficient atmospheric conditions. Procedures for the planning, installation, operation and maintenance of booster fans are also presented. A case study illustrating the design and siting of a major booster fan installation in a potash mine, supported by computational fluid dynamics analysis, is presented.INTRODUCTIONIn large underground operations with complex ventilation networks offering high resistances, the never ending increased required quantities of air can almost only be supplied through use of high pressure main fan systems. These fans may, in effect, induce significant leakage losses in the system, having a negative impact on safety performance. In such cases, booster fans can be designed to decrease the main fan pressures and reduce the leakage flows, improve system efficiency and reduce costs. In well designed systems, booster fans can thus be used to redistribute the airflow and assist the main surface fans.When the pressure supplied by the main fans is insufficient to meet the ventilation circuit pressure requirements, booster fans are placed in strategic locations where pressure boosting is essential. Booster fans are typically sited in sections of the circuit offering high ventilation resistance and requiring this form of ventilating air motivation. Booster fans are thus required when the mine expands, and so the resistance of the ventilation network, and the primary fans no longer can supply the required pressure and flow."

Jan 1, 2019

By W. L. Brown

"The properties of Base Metal Mining Corporation are in Yoho Park about 2 1/2 miles northeast of Field; British Columbia; on the main line of the Canadian Pacific railway. There are actually two mines; the Monarch on mount Stephen and the Kicking Horse on mount Field; separated by the steep valley of Kicking Horse river. The outcrops of the orebodies range from 4; 900 feet to 5; 300 feet above sea-level. The concentrator is situated below the Monarch mine and is connected to the main portal by an aerial tramway. The ore from the Kicking Horse mine is conveyed by aerial tramway to a storage bin on the main highway and is then trucked to the concentrator.During the construction of the Canadian Pacific railway through Kicking Horse valley, galena float was found at the base of mount Stephen. The East Monarch outcrop was staked in 1894. The outcrop of the West Monarch ore body on the cliff face of mount Stephen was not discovered until 1916. The Kicking Horse orebodies on mount Field were discovered a few years later. In 1912, a 75-ton concentrator was erected, which operated at intervals until 1924. During this period approximately 42,000 tons were mined and milled, largely from the East Monarch orebody. In 1928, the Base Metal Mining Corporation, Limited, was formed to take over the Monarch and Kicking Horse mines. A 300-ton differential flotation concentrator was erected and production started in the autumn of 1929. In a very short time, however, the low price of metals forced the mill to shut down until August 1933. From 1929 to 1935, when the mill again ceased operation, a total of 256,500 dry tons of ore, averaging 1.59 oz. silver per ton, 9.7 per cent lead, and 12.6 per cent zinc, was mined and milled, largely from the West Monarch orebody. After a period of further underground development, the concentrator reopened in 1940 and is still in operation. From 1940 to the end of 1944, 354,363 tons of ore was milled, averaging 5.32 per cent lead and 10.47 per cent zinc."

Jan 1, 1954

By J. Farrell

The Canadian government ratified the Kyoto Protocol in December 2002 and, prior to ratification, committed to equitable distribution of the burden of implementation. The Federal government's Large Final Emitters group is working with industry to develop covenants that will consider the unique nature of the company's operations and not unreasonably burden any one sector or company. Ensuring equitable distribution must consider local, national and international issues. From a Canadian iron ore producers perspective, the fact that most of the iron ore production in the world is in countries that have no Kyoto commitment is a critical issue. Another issue unique to this sector is the increased addition of fluxing agents in iron ore pellet production which has shifted some process related greenhouse gas emissions from steel producers to iron ore producers. While the objectives of the Kyoto Protocol are primarily environmental, the economic implications for Canadian industry are not trivial. For decades Canadian companies have been actively improving energy efficiency and reducing greenhouse gas emissions to maintain a global competitive position. Production of iron ore pellets is an energy intensive process and the Iron Ore Company of Canada (IOCC) is the largest Canadian producer. In 2002 IOCC identified energy and Kyoto Protocol implementation as critical risk factors for their organization and appointed a full time Energy Manager. In January 2003, IOCC initiated a comprehensive process for identifying energy cost reduction opportunities and established an Energy Master plan. This process included:

Jan 1, 2004

By J. Marks

The measurement of greenhouse gas (GHG) emissions from primary aluminium production and inventory of these emissions of carbon dioxide and PF Cs have become an important issue for primary aluminium producers. Most global producers have either voluntary emission goals or emissions limits established through national regulatory requirements. International good practices for inventory of these emissions for national governments are established through the Intergovernmental Panel on Climate Change (IPCC). The current good practices, last updated in 2000, are being revised and are expected to be adopted by governments in the spring of 2006. There are a number of changes expected in the guidance that will impact how facilities account for their GHG emissions. This paper describes the changes to the guidance and the implications of these changes for aluminium producers.

Jan 1, 2006

By Robert B. Parsons

"Finance Minister Paul Martin's first budget disappointed almost everyone. The business sector was disappointed at the some what feeble attempt to grapple with the country's deficit. The mining industry was disappointed by tax proposals regarding mine reclamation that fall short of the industry's needs. Has anybody been happy with a federal budget? Federal Budget DisappointsThe federal government's budget papers that were tabled on February 22, 1994, contained a rather bizarre mixture of unrelated tax proposals. The budget signals an unexpected attack on the tax treatment of debt settlements, on certain types of corporate reorgani2ations, and on income earned by foreign affiliates. This is an old style budget, which proposes a pot pourri of technical changes and policy initiatives. Mine ReclamationEffective February 23, 1994, a taxpayer's contributions to a prescribed mine reclamation trust fund will be deductible as a current expense. The budget papers do not provide a definition of what will constitute a ""prescribed"" trust: this definition will surface in due course. However, the budget papers indicate that:• income earned in such trusts will be subject to tax each year;• all withdrawals from the trust (including income already taxed) will be included in computing the income for tax purposes of the recipient;• reclamation costs will continue to be fully deductible at the time incurred; and • contributions, trust earnings, and withdrawals will not be taken into account for the purposes of determining a taxpayer's resource allowance."

Jan 1, 1994

It?s a pleasure to be with you in Vancouver today to reinforce the good work you and your companies do to develop and operationalize new technology as a lever to improve operational performance and reduce our impact on the environment in absolute terms. Although I will use the work we do at Shell to reinforce this perspective, the principles apply to all of us in this industry regardless of whether you are a producer or supplier. I?d like to help demystify the future of Canada?s oil sands based on Shell?s view of global energy developments, including forecasted demand. One of the incontrovertible truths of this era of global energy defines change as an unchangeable law of progress. Another tells us that the art of progress is to preserve order amid change and to preserve change amid order. These axioms help frame the increasingly public debate about the future of Canada?s oil sands. I hope to illustrate how Shell?s commitment and investments create positive progress that embraces change amid order in the oil sands. I?m going to spend a little time today to focus the spotlight on the future of the oil sands to help demystify Canada?s hydrocarbon energy future. To do that, I?ll identify the features of our future energy security, including three hard truths about global energy that drive Shell?s business imperatives. Then, it?s instructive to examine Canadians? current consciousness about oil sands sustainability.

Oct 1, 2009

By L. Louis

High resolution X-ray computed tomography imaging (with voxel size 48 µm) was conducted on various sandstone samples with different initial degrees of heterogeneity. All samples were imaged intact, and some after having developed localized compaction features in conventional triaxial experiments at high confining pressure, i.e. in the shear enhanced compaction domain (Wong et al., 1997). Our analysis of heterogeneity from X-ray CT data is based on the use of the coefficient of variation d =s /µ (s being the standard deviation and µ the average value). The coefficient of variation was shown by Otani et al. (2005) to be a convenient indicator of material heterogeneity in CT images of experimentally deformed sand piles. The authors reported differences in d before and after their experiments, and interpreted these differences as the effect of grain crushing resulting in more even material distribution within the voxels, hence in lower d values. The same concept was used by Louis et al. (2006) to image contrasts in d values throughout a volume of rock that had developed compaction bands in triaxial laboratory testing, knowing that the bands that had formed could be identified by visual inspection but not on the X-ray CT images. This study resulted in a radically enhanced image of the discrete compacted zones within the CT-scan series, whereby more deformed areas showed relatively low values of coefficient of variation due to grain crushing and pore collapse, as compared to nominally undeformed areas.

May 1, 2009

By Karen I. McMaster

"Abstract - The mining industry has endorsed the concept of sustainable development in principle. We now need to ensure that it is "lived" throughout the workplace. Frequently, sustainable development is viewed as just a policy and, more often than not, it is regarded as something that is applicable only to the areas of health and safety, environment, or community philanthropy. However, sustainability requires the collective action of an entire organization on a regular basis, a corporate culture where values are transformed into action.This paper reviews two of the many functional areas through which sustainable development can be pursued. Law and internal auditing are powerful means of instilling values, driving behavioral change, and improving performance. The development and role of each tool vis-a-vis sustainability is reviewed. Suggestions are offered regarding option and joint venture agreements, contract management programs, and various auditing programs based upon international standards and processes, market indices, and codes of conduct.The goal of this paper is to provide a general overview of these functional areas and to encourage further dialogue between employees and management in the workplace. It is hoped that others in the industry will examine the values of their companies, and review the ways in which individuals in all functional areas work, or want to work, on a daily basis. If we can harness collective commitment, creative thinking, and action in sustainable development, then the desired acceptance by stakeholders and improved financial performance will follow."

Jan 1, 2003

By D. Magoon

The metals industry has enjoyed a resurgence in prices and demand for its commodities during the global surge in economic activity that began in 2005. This success has brought with it an unprecedented demand for professionals in all sectors of our economy. Nowhere is that more true than in the mining and metallurgy sectors. However, this welcome improvement follows on the heels of almost two decades of challenging markets for the mining and metallurgy. Our sector's protracted economic slump created a paucity of demand for professionals that had several consequences. Our industry came to be viewed as a low ?tech, uninteresting place to work. Low demand for professionals encouraged students to seek other career options. Reduced demand for graduates, coupled with diminished program funding by our sector, resulted in dramatic shrinkage in university mining and metallurgy programs. This paper explores the lessons to be learned from our recent economic history and discusses some strategies for addressing our image issue. Attracting and retaining good employees is also strongly influenced by a company's reputation and record as a good employer. This reality is very well illustrated by the findings of an international survey undertaken by Towers Perrin in 2005 of 86,000 employees of mid-sized and large companies in 16 countries. The key findings related to attracting and retaining employees are presented. These findings are also discussed in the context of their specific applicability to the mining and metallurgy industry.

Jan 1, 2007

By John (Jack) D. Young, Frank M. Wheeler

Metallurgical plants are typically large, complex facilities. Their design is a multidisciplinary activity with a wide range of inputs, based on: the business case; metallurgical and process requirements; and the main processing equipment selection. Many constraints limit what can be achieved. Appropriate phasing of the design and development, and clear go/no-go decision criteria, are critical to successful implementation of a plant design project. Risk management concepts are used as a framework for successful project development, working from the business case, through project development, to implementation and startup, paying constant attention to technology, safe design, and sustainability. 1.1 INTRODUCTION The subject of “Metallurgical Plant Design” is the design of metallurgical plant facilities in the broadest sense. Plant design represents the culmination of many multidisciplinary activities: knowledge of process metallurgy is applied to design facilities to manufacture useful, economical, metal-based products. In the field of metallurgy, plant design is often overlooked, and its unique requirements are commonly not well understood, let alone appreciated. This book is a contribution to remedying this situation. The focus is the specifics of the metals industries, because an extensive literature already exists on the general topic of plant design.

Jan 1, 2015

By Jeonghwan Kim

Intelligent Excavation System (IES) has been considered to be one of the desirable solutions to improve the productivity, quality and safety of the current earthwork processes. IES is composed of various hardware and software modules including task planner (work command generator), local and global work environment sensors, GPS and other sensors to acquire the excavator?s status, robotic controller and electronic valves, and the manipulator (excavator). A data communication manager was required to coordinate the signal or data-flow in between these modules considering the operational status of IES such as; excavation start/completion, truck detection, terrain model update, emergency stop, local sensing, GPS/motion sensor data handling, and so on. This paper presents the role and functions of this data communication manager. After every possible operational status of IES operation was identified, a protocol of each communication process in the form of string-type was made. The components of IES are connected with either wired or wireless network. Therefore, they can communicate with the manager using socket (TCP/IP) communication. The data communication manager is also capable of accessing a web-based project management information system, which constantly updates the performance of excavation robot to online database.

Aug 1, 2013

By Julia Pflieger, Manfred Russ, Johannes Gediga

This paper shall show an economic feasible approach to implement Greenhouse Gas (GHG) reduction measures into the mining and metallurgy industry. The goal to improve energy consumption is directly linked to the reduction of GHG emissions and therefore directly in correlation with the economic viability. A baseline scenario of the considered reference system and of the respective reference year has to be defined, mapped and analysed. In a second step an analysis of the same operation using available and prospected Best Available Technology (BAT) processes is carried out to generate a basis for a benchmark system. The identified reduction potentials are reported and the GHG emission reductions are put into relation to the investment cost of the new process technologies / process adaption to be implemented. This economic feasibility calculation is necessary to realise a cost efficient GHG reduction roadmap implementation into the company's business operations. The GHG reduction roadmap is developed using ratios between GHG reduction and investment / operating cost to get an indication for a sequence for implementing carbon emission reductions measures.

Jan 1, 2010

By G. W. Brooks

This short article is quite different to the general run of papers that are presented to the Institute, but no apology is offered because I consider that first-aid and mine-rescue work are of equal importance to many other subjects that are dealt with in our Transactions. Members of the Institute should be as much interested in the safety of persons engaged in the mining industry as they are in the practical methods of modern mining. We must not only do our best to conserve life and property by adopting every known device to that end, but we must also prepare ourselves so that we may take prompt and effective action when life is in danger, or when property is subject to loss. The need for such preparation in Alberta is perhaps greater than in most places where mining is carried on, and we must spare no effort to assemble at every mine men who are well trained in first-aid and mine-rescue work. The large area over which the mines are distributed renders central training stations out of the question, hence the need for local rescue-teams. Hospitals with skilled staffs, close enough to the mines to be convenient, also seem to be out of the question; therefore the greater need of a high standard of first-aid training for the people in our mining camps. The Government mine-rescue cars are supplied with the equipment necessary for training persons in this essential work and also for dealing with disasters should they occur. The question then arises: are there a sufficient number of men who are trained ? If so we can rest assured that what is possible to be done will be done. But if a sufficient number of trained men are not available much loss of life and damage to property is likely to result.

Jan 1, 1925

By L. Dufourm

This paper presents a review of plant layout considerations incorporated into recent designs of SAG/Ball mill circuits for two medium sized concentrators. The plant layouts presented and the design concepts discussed, relate to smaller SAG circuits, but can equally apply to larger milling circuits. Included are design concepts and ideas introduced by the various project teams, and the focus is on the primary factors of any layout design which are safety, constructability, operability, and capital cost.

Jan 1, 2012

By BARRY BANNATYNE

About 90 per cent of Manitoba's industrial minerals production is for structural materials. Most of these come from the Paleozoic rocks west of the Precarnbrian Shield, or from glacial deposits that are extensive throughout Manitoba. The major raw materials are sand and gravel, and carbonate rocks for crushed stone (and also dolomite for high-magnesia lime, high-calcium limestone for lime and Portland cement, and dolomitic limestone for Tyndall stone). Glacial lake clays are used both in cement and in lightweight aggregate. The Jurassic and Cretaceous strata exposed along or near the Manitoba Escarpment include siliceous, carbonaceous, kaolinitic and illitic shales, all of which are quarried by Red River Brick and Tile in the Pembina Mountain and Ste. Rose areas for use in a brick plant at Lockport. Non-swelling bentonite near the base of the Pembina Member of the Upper Cretaceous Vermilion River Formation is of value as an absorbent clay, and is the only commercial source in production in Canada. It has been quarried by Pembina Mountain Clays Limited since 1940. Gypsum occurs in the Jurassic Amaranth Formation and supplies much of the market for wallboard and Portland cement additive in the Prairie Provinces. Quarries are operated at Gypsumville by Domtar Construction Materials Limited, and north of Amaranth by Westroc Industries Limited. Silica sand from the Ordovician Winnipeg Formation is of glass-grade quality, and about 100,000 tonnes are produced annually by Steel Brothers Canada Limited on Black Island . It is used as a glass sand, as foundry sand, for sand blasting, and as a filter-bed sand .

Jan 1, 1984

By A. Poor Zaeif Doost

With columns being installed in rougher section at Miduk Copper Complex, the rougher feed mainly reports to rougher-scavenger cells. To evaluate the efficiency of regrinding circuit, we conducted flotation experiments on samples of the feed and the products of the regrinding circuit. The grade difference of these products at 85% recovery was considered as the efficiency index. Results show that, with weight recovery of the rougher-scavengers the efficiency of the circuit increases. Exclusion of the rougher-scavenger concentrate from the feed to the regrinding circuit, resulted in an increase in the efficiency index from 10.12 to 17.6%.

Jan 1, 2012

By Charles G. Kemsley

IN view of the truly remarkable development of special steels for special purposes, the mining industry has for years looked forward to a time when steel makers would come forward with a product which would be an improvement over the straight carbon steel which has always held the field for drilling rock. In order to avoid making changes in conventional shop practice, the industry has perhaps been too insistent upon obtaining a water hardening steel which could be handled in the blacksmith shop by long established methods. As early as 1932 or 1933, an oil-hardening tool-steel of the one per cent carbon, plus chrome, plus molybdenum type was applied to hollow drill steel. It was known as a hard as well as a tough steel, and one that, theoretically, should give a good account of itself as a rock drill, if properly heat-treated; and so it has proved in actual trials. There were numerous deterrents which retarded adoption of this steel. For several years there has been a constant improvement in the drilling qualities of the straight carbon steel, and, considering the higher unit price ? of the alloy, there has been considerable doubt in the minds of some mining? men as to what advantage there might be in the use of alloy over straight carbon for hollow drill steel. The alloy being an oil-hardening steel, its adoption meant having two kinds of steel in the mine, for a time, and that spelled trouble, unless some positive means of identification was adopted. The hardening and forging ranges of alloy steel being narrow also made necessary much closer control over these operations if poor results were to be avoided. These thoughts undoubtedly prevented its use becoming wide-spread, for, as a matter of actual record, less than fifteen per cent of all the hollow drill steel used in Canada today is alloy.

Jan 1, 1942

By S. Kobayashi, N. Ohara, T. Aoki, S. Sakurai, M. Iwano, M. Shimo, I. Otsuka

"This project is the upgrading of a commuter line of approximately 76 km to improve the railway system in Istanbul metropolitan area. Railway tracks have been connected between Asia and Europe through a tunnel under the Bosphorus Strait. The length of these underground structures sums up 13.6 km. In this paper, the observational construction management based on field measurement performed at large scale underground railway station (Sirkeci station) constructed by means of New Austrian Tunneling Method (NATM) is described and the mechanism for generation of ground surface settlement above this station is discussed.Buildings above Sirkeci station are overcrowded. About 60% of the buildings are made of reinforced-concrete (RC) and others are of brick. Based on the investigation into the predicted settlement and inclination, necessary actions such as structural reinforcement and soil improvement have been conducted for dilapidated buildings.Rock mass around Sirkeci station consists of alternative strata of sandstone and mudstone. It is overall soft rock with an elastic modulus of 150 MPa, partly including fractured zones. Overburden is about 30 to 40 m. The thickness of unconsolidated sand layer distributed on the bedrock is about 10 m. As a result of in-situ permeability tests, the coefficient of permeability of the sand layer is about 1.0x10-3 cm/s. Fill layer of about 10 to 25 m in thickness covers the sand layer at the ground surface. The fill layer contains a lot of artificial waste like splinters of wood, brick chips and mortar chips, etc. in addition to gravel, sand, silt and shells. The coefficient of permeability of fill layer is estimated to be 1.0 x10-2 cm/s, which is one-order greater than that of the sand layer. Fill layer consists of ancient city ruins of ages respectively from the Eastern Roman Empire, the Byzantine Empire and the Ottoman Empire and has a lot of gaps.The underground part of the Sirkeci station was excavated through a ventilation shaft. Ground surface settlement occurred more than predicted. Therefore, back analyses were performed in order to precisely predict the next-step settlement. However, back analyses with elasto-plastic models could not simulate the actual phenomena and hence, an anisotropic-damage-parameter model developed by Sakurai (1999) was adopted for the back analysis. Furthermore, as the excavation of tunnel proceeded, the ground surface settlement exceeded the predicted value again. Based on the monitoring results, it seemed that pore water pressure decreased by the tunnel excavation resulted in the soft rock and soil to be contracted due to the increase in the effective confining pressure. A coupled hydraulic-mechanical analysis was applied to explain the relationship between decreased pore water pressure and ground surface settlement. The settlement due to drainage from tunnel wall was well-estimated in the coupled hydraulic-mechanical analysis.However, further settlement occurred more than predicted again and again. Though it was very difficult to clarify the reason of the large settlement, it was recognized that the unexpected ground surface settlement resulted from the existence of the large gaps in the fill layer that was greatly compressed. The final settlement reached up to 327 mm."

Jan 1, 2015

By Evans B. Mayo

ABSTRACT Orange Footwall 'sill' is locally concordant locally discordant, with the structure of its sedimentary walls. The sediments were folded in two directions. Folds, following both these directions, are preserved in the concordant portion of the 'sill'. It seems, therefore, that the porphyry has replaced the sediments, thus preserving within itself their structure. During replacement, the nascent porphyry may have been much weaker than its walls. Accordingly, under directed pressure, the porphyry could have flowed locally, disarranging the replaced structures within it and developing a flow structure discordant with the folds in the sediments. Some such action may account for the discordant parts of the 'sill'. INTRODUCTION The senior author has seen certain granitoid massifs that have an internal structure vastly different from, and discordant with, the structures in their wall rocks. It seems that? such massifs have moved independently of their surroundings. Yet, a structure section elsewhere in the same mountain range may reveal granitic rocks with internal structures that appear to continue the structure of the invaded rocks. In such a case, it is at least thinkable that the granite has replaced the older sediments or volcanic rocks. In February, 1950, the writers mapped, on 15 level of the Nickel Plate mine, near Hedley, B.C., a diorite or gabbro porphyry 'sill' that, in one cross-cut (1503), appeared to be quite concordant with the wall-rock structures, whereas in another cross-cut ( 1500) about 100 feet to the south, the same porphyry was discordant (see Figure 1).

Jan 1, 1951