Search Documents

By The Staff

"IntroductionThe difficulties to be overcome in shaft sinking and development at depth are centred at McIntyre in and around No. 12 shaft. Generally they have been due to increasing pressures and temperatures and to changes in geological structure. This paper describes the difficulties and the measures taken to meet them.No. 12 ShaftEarly in 1932 McIntyre decided to sink an internal shaft from the deepest level, the 3875, to explore and develop known veins extending below that horizon. The location selected was a point 1,500 feet south and 1,000 feet east of No. 11 shaft, the main operating shaft through which the men, ore, and most of the materials are handled Shaft and auxiliary equipment we1e laid out for 3,000 feet, that is to 7,000 feet below the surface. The shaft was to be capable of handling 1,500 tons of ore daily from the lowest level, and was to provide ventilation, compressed air, water, and electric power to service all levels.No. 12 is an internal, vertical shaft extending from the 3875 to the 6825 level and bottoming at 7,007 feet. It is a rectangular, four-compartment shaft, 21 ft. 9¾, in. by 6 ft. 3¾ in. outside the timber (Figure 1).There are two hoisting compartments and one airway compartment, each 4 ft. 10¾ in. by 5 ft. ¾ in. inside dimensions, and a combined manway, pipe, and cable compartment 4 ft. ¼ in. by 5 ft. ¾ in. Levels have been established at 150-foot intervals, pump stations and sumps at 1,000-foot intervals, and. there are two loading pockets, one at the 5525 and the other at the 6900 level.The shaft was sunk in two stages. The first stage, consisting of preparation above the 3875 level and sinking to 5585 feet, was completed by March 31st, 1935. The second stage of deepening the shaft from 5,585 to 7,007 feet was started August lst, 1946, and completed three years later."

Jan 1, 1950

By John J. Laffin

"IN THE BOOK that has been rated the best seller of all time, it is predicted that man will earn his livelihood by the sweat of his brow. Apparently man has accepted the statement as a challenge and has been attempting to refute it ever since, as he continues to transfer the workload to his inanimate servants - the many types of machines and other labour-saving devices that are available to assist or perform for him in the normal tasks of the day. The history of the evolution of the use of energy takes us back to primitive man, who existed in a very low energy environment, the only energy available being his own muscle power. Although man took a great leap forward when he discovered fire, which was used for lighting, heating and cooking, he still depended upon his own muscles for power. Early man's greatest achievement was probably the invention of the wheel, which permitted him to utilize the muscle power of animals. While still in a very primitive state when viewed from the perspective of the twentieth century, man, with fire and the wheel, had achieved a standard of life far exceeding that of his predecessors. Looking beyond the very basic elements of human energy, fire and the muscle power of animals, we find the next additions of energy coming from man's mastery of other elements of nature. The Phoenicians utilized the power of the wind and the Romans adapted the energy of falling water to the water wheel."

Jan 1, 1972

By D. D. Tannant, H. Ozturk

Thin spray-on liners are increasingly being used as rock support in underground mines. The adhesive strength between the liner and the rock surface is an important design parameter. Adhesion tests were conducted to assess the impact on adhesion of the presence of oil, water, and dust on a substrate, and the roughness and grain size of different substrates. Other factors such as curing time, loading rate, and liner thickness were also considered. Adhesion was measured using a pull test of a 33 mm diameter elevator bolt attached to an over-cored section of liner with strong epoxy. Most tests were performed using Tekflex liner material, although five other liner products were also tested. Adhesive strengths of about 2 MPa can be achieved with Tekflex under optimal conditions. Long-term creep tests showed that the adhesive strength could drop by at least 50% when the liner carries load for about a month. Where the rock surface is contaminated with dust or the rock is weak in tension, it may be difficult to reach adhesion strengths of 1 to 1.5 MPa. As the thickness of the liner increases, the adhesive strength to a substrate appears to decrease.

Jan 1, 2007

By J. C. Hawkins

Determining moisture content and rate of flow of a solid product make measurement and control of dryers unusually difficult. This paper de-scribes a method of accomplishing this with readily made air-temperature measurements. The system can cope with changes in feed moisture and feed rate. It does not measure solids temperature. The system's application to several typical rotary dryers is described, and control schemes using feedforward techniques are explained.

Jan 1, 1971

By R. D. Browns

In his Budget Speech on March 31, 1 977, the Honourable Donald S. Macdonald expressed concern about the financing of investments through new equity issues. He mentioned the need to render more attractive participation in the equity market by investors in all in come brackets. One of the measures introduced in the budget to accomplish this goal is the proposal to increase the dividend gross-up and tax credit in respect of most dividends received by an individual from Canadian companies. The following comments and tables serve to illustrate the impact of this particular proposal.

Jan 1, 1977

By Dan Miners

"This presentation will provide an overview and understanding of Mine Safety and Health Administration (MSHA) and Ontario Regulations for Mines and Mining Plants. It includes discussions on the history and practical development of the standards and an overview of engineering best practices from a construction, maintenance and operational viewpoint. INTRODUCTION Ontario is one of the safest mining jurisdictions in the world and has some of the most comprehensive regulations for the construction, operation and maintenance of a mine. In the USA, several operators have adopted some or all of the practices prescribed by the Ontario Regulations as an internal procedure. Experience has demonstrated that these plants are indicating less unplanned downtime and fewer issues with MSHA inspectors in their hoist plants. HISTORY AND THE REGULATIONS Both Canada and the USA have had some form of laws governing the operation of mines since the late 1890s. The paths of legislation have run in reasonably parallel lines, continually improving the health and safety conditions in the mining industry. Ontario Mine Health and Safety In the 1970s the accident rates in mining were higher than any other industrial sector; this prompted a Royal Commission on the Health and Safety of Workers in Mines (the Ham Report). The recommendations of this report, published in 1976, generated several changes in the regulations regarding worker safety in mines. Following the release of the Ham report, the Occupational Health and Safety Act (OHS) was passed by the Legislature in 1978. The Act is a set of comprehensive laws governing almost all Ontario workplaces, and it replaced separate laws governing different industrial sectors. OHS is enforced by the Ministry of Labour (MOL), and this discussion will focus specifically on Ontario’s Occupational Health and Safety Act, R.R.O. 1990, Regulation 854, Mines and Mining Plants, Part X Mine Hoisting Plant (Ontario Regulations). USA Mine Health and Safety A coal mine explosion in West Virginia and medical studies on occupational disease led to the 1969 Federal Coal Mine Health and Safety Act (Coal Act). The Coal Act was the most comprehensive and stringent Federal legislation governing the mining industry to date. The Mining Enforcement and Safety Administration (MESA) was formed, following the 1973 Act, as a new departmental agency to assume the enforcement of safety and health in mines. The Federal Mine Safety and Health Act of 1977 (Mine Act) transferred enforcement responsibilities from the Department of the Interior to the Department of Labor and named the new agency the Mine Safety and Health Administration (MSHA). This agency enforces the Code of Federal Regulations (CFR), and this discussion refers to CFR Title 30 Mineral Resources, Chapter I Mine Safety and Health Administration, Department of Labor, Subchapter K—Metal and Non-metal Mine Safety and Health (MSHA)."

Jan 1, 2019

By C. Fleming, J. R. Goode

ABSTRACT: Data were produced from two uranium project studies that were conducted in 2008, both involving uranium recovery from leached slurry by resin-in-pulp (RIP) with strong base resins. In both studies, excellent metallurgical results were produced. The loaded resins were eluted with strong sulphuric acid and recycled through RIP circuits in an integrated process. Resin losses by either abrasion or mechanical breakage were immeasurably low. Metallurgical results from these two campaigns are presented, along with a case study economic analysis of RIP versus the alternative processes of counter-current-decantation or filtration and solvent extraction.

Jan 1, 2011

By T. Senga, T. Namihira, S. Terada, S. Owada

"Electrical disintegration (ED) has been well known as a good comminution method to improve liberation of compositional phases because it was reported that electron avalanche could occur preferentially at phase boundary. But the detailed mechanism of the ED has been still not known. This paper describes the results of ED experiments using synthetic binary sample, copper/resin, under the conditions of various distance between electrodes, and discusses the energy distribution in the three kinds of phenomena in the ED process, which are(1) streamer progression in water, (2) electron avalanche in water, and (3) electron avalanche in solid sample, by measuring current and voltage with elapsed time. Then, it has been found that the energy distribution in the phenomenon (1) is quite low and that the distribution in the phenomenon(2) had a considerably large compared with that in the(3), which indicates that the shockwave generated in water could contribute much to the sample breakage.INTRODUCTIONElectrical disintegration (ED) has been well known as a specific comminution technology which enhanced selective breakage at phase boundary and lead to a good liberation among compositional phases1-6),but the detailed mechanism has not been clarified yet. This study describes energy distribution among the phenomena in the ED process by using a synthetic binary sample, copper/resin, the phenomena of which are (1) streamer progression in water, (2) electron avalanche and shockwave generation in water and (3) electron avalanche in solid sample usually at phase boundary. The energy distribution could be calculated from ED experiments and from voltage-current changes between electrodes as a function of elapsed time.SAMPLE AND EXPERIMENTALSampleThe sample used in this paper was a synthetic binary solid of copper/resin as shown in Figure1.Cut and polished pure copper lump was put into silicone mold and melted epoxy resin was poured into it and cooled, then, finally the binary sample was polished and molded in the form of 10 mm * 10 mm * 10 mm."

Jan 1, 2017

By D. Markwart, B. Volk

Anode effects are a phenomenon of the aluminium electrolysis process which produce potent greenhouse gases called PFCs (CF4, C2F6). With concerns surrounding global warming, and increasing regulation of GHG emissions, anode effects have become a significant sustainability issue for aluminium producers. In modem smelters, sophisticated computer control and automated alumina feeding systems allow for very tight control of the alumina concentration in the electrolyte and thus very low anode effect frequencies. Older smelters, however, do not have these systems and must either invest heavily to obtain them, or find other, innovative ways to reduce anode effect frequency. This paper will present the integrated approach to anode effect reduction used in the Vertical Stud Soderberg (VSS) potlines at Kitimat Works. Through an innovative combination of simplified signal analysis, modified alumina feed control logic, anode effect prediction, and anode effect prevention using a pager based communication system, Kitimat W arks has been able to make significant reductions to its anode effect frequency.

Jan 1, 2006

By J. Lee

A monolithic caisson is one of the major structural components commonly used in the construction of docks, breakwaters, and container terminal quay walls. Since the structure of monolithic caissons is typical and somewhat simple, its design process is also typical and repetitive, but still time consuming. To reduce the total time and enhance productivity, we developed a parametric model in Revit to automatically generate a 3D model of a monolithic caisson. It is designed to generate the Revit model of a caisson with concrete body and reinforcing bars. The size of caisson, the number of reinforcing bars, and the space between reinforcing bars are automatically changed when users update parameters. This paper presents how we developed this parametric family in Revit for monolithic caisson design and how it would enhance its design process.

Aug 1, 2013

By Robert B. Parsons

"The Canadian Exploration Incentive Program (CEIP), which was announced by the federal government on May 3, 1988, promises to maintain the viability of flow-through shares as a financing mechanism which has proven to be so crucial to the health of the junior exploration sector. This month, Tax Notes examines, the main features of CEIP, which will come into play on January J, 1989. IntroductionOn May 3,1988, the Honourable Marcel Masse, Minister of Energy Mines & Resources, and the Honourable Gerald Merrithew, Minister of State (Forestry and Mines) announced the Canadian Exploration Incentive Program (CEIP). Under CEIP, the federal government will make cash payments to eligible applicants equal to 30% of eligible exploration expenses. CEIP payments will be available with respect to both mineral, and oil and gas, exploration. In essence, the program will replace the ""mining exploration depletion allowance"" (MEDA) presently applicable to mineral exploration, and the Canadian Exploration and Development Incentive Program (CEDIP) which is presently available to the oil and gas exploration sector.This paper discusses briefly the main features of CEIP insofar as the program will affect mineral exploration. The comments herein are based on the Canadian Exploration Incentive Program Act which received Royal Assent on July 21, 1988, and on a discussion paper which was released by EM&R in May 1988. The bulk of the rules relating to the program will be in the form of regulations which have yet to be finalized. It is understood that EM&R would like to have the regulations in force by October I, 1988, when the oil and gas portion of CEIP becomes effective. (The rules relating to mineral exploration will become effective January I, 1989)."

Jan 1, 1988

By J. Clark

Erosion control during the mining cycle can be more effectively planned using Erosion and Sedimentation Control Plans (ESCPs). This raises the issue of who should develop an Erosion and Sedimentation Control Plan Guidance document (ESCPG) to standardize the content of ESCPs. A search for ESCPG documents in Canada revealed no examples for mine sites. In the U.S. there are a number of regulatory authorities who developed such documents for mine sites, including EPA. An ESCPG is expected to result in: (a) plans will be more standardized (b) more clarity and efficiency for those generating ESCPs; (c) assisting regulators tasked with reviewing/approving ESCPs; (d) providing guidance for the mine effluent permitting process relative to sediment control; (e) providing a basis for developing and including ESCPs in the Environmental Assessment (EA) phase and the mine economic assessment; (f) applying and optimizing ESCPs above the ?watersheds? of sediment ponds; (g) utilizing the ESCPG document for ?exploration? sites; (h) lowering the risk of adversely impacting water quality downstream of mining activities; (i) providing a methodology for determining the need for sedimentation pond(s) during the construction and production phases; and (j) providing a clear environmental sustainability message relative to sediment control if the mining industry takes the lead in developing an ESCPG. ESCPs will proactively create increased administrative (regulatory) efficiency in the EA and sub-EA reviews relative to erosion control and sediment release from mine sites. This also assists the new initiative in BC, One Project, One Process (OPOP) and synchronous permitting (a variation of concurrent permitting): as an example, enhanced erosion control planning at the EA phase then allows the synchronous permitting initiative to proceed efficiently, particularly for the mine permit (Ministry of Energy, Mines and Natural Gas) and effluent permit (Ministry of Environment). Approximately twenty more management plans (e.g. ARD/ML, explosive management, emergency response, hazardous waste, sediment pond operation, environmental effects, environmental sampling, etc.) may also be entered into the EA process to create increased efficiency, and then feed into the synchronous permitting effort. The BC OPOP initiative also adds support to the Canadian Federal ?One Project, One Review Process? approach. The ESCP and a sediment pond management plan will also address the Canadian Metal Mining Effluent Regulations requirement for all discharges from mine sites to meet a grab sample of 30 mg/L Total Suspended Solids.

Aug 1, 2013

By E. Peters

Roasting processes are divided into several elementary mechanisms, any of which could be significant or pre-dominant in a particular roast. The elementary processes considered in-elude beat transfer, gas-solid inter-actions with accompanying mass transfer between the bed and furnace atmosphere, vapor phase transport processes in solid-solid interactions, and solid phase diffusion processes. Examples are chosen of processes in which one of these mechanisms pre-dominates and some recently obtained data is presented to support the existence and significance of these mechanisms. Proposals are also made for future research in these areas, and for utilizing the information in the improvement of roaster capacities’ OASTING of ores as a preparative treatment for smelting or leaching has been practiced for so long that its origin has been lost in antiquity, but little has been under-stood of its basic nature until fair-ly recent times. The nominal chemistry of roasting processes is now understood; that is, the initial chemical com-pounds present in the ores or con-

Jan 1, 1961

By James A. Robertson

"This paper is the result of a continuing investigation begun in 1953 by government geologists and mining companies. Previous work is reviewed and the development of several stratigraphic nomenclatures and correlation schemes is traced, culminating with the interim report of the Federal-Provincial Committee on Huronian Stratigraphy formed in 1966.The stratigraphy, structure and correlation of the Huronian rocks of the Blind River area and the region between Sault Ste. Marie and Sudbury are reviewed. The area is underlain by three Precambrian units: (1) the Archean greenstones and granites, (2) the Huronian sedimentary and volcanic rocks and (3) the post-Huronian intrusive rocks. The Huronian rocks, largely quartzite and conglomerate with greywackes, argillites and carbonates, were laid down in shallow water transgressing over the eroded Archean basement. Thickness and facies changes indicate a northwesterly source, northerly overlap and deposition controlled by basement topography. Polymictic conglomerates, occurring at least at three horizons, represent tillites and are associated with varvites with dropped clasts. These are best developed in the Gowganda formation, which varies from a continental glacial environment in the north to a marine glacial environment in the southeast.There were at least three phases of post-Huronian igneous activity, probably related to several periods or phases of late Precambrian deformation and metamorphism: (1) sills of Nipissing diabase and rather younger diabase dikes; (2) the Cutler Granite and Croker Island Complex; and (3) dikes of Keweenawan olivine diabase.Copper mineralization is associated with the Nipissing diabase. The uranium ores are found in pyritic quartz-pebble conglomerate near the Huronian Archean unconformity, particularly in ancient valleys; they are considered to be placer deposits modified by later events. Uranium production from the Blind River camp to the end of 1966 was 128,160,096 pounds U308 valued at $1,203,840,848 derived from 56,077,179 tons of ore grading 0.11 per cent U308.Within the Blind River and adjacent areas, future discoveries will probably be the result of costly systematic deep-drilling programs accompanied by detailed geologic studies of the type carried out by oil companies and probably computer-oriented."

Jan 1, 1969

By S. A. Pence, A. I. McCallum, V. de Korompay

"Special salt protection rings containing a water-swell• able, polymeric sealant are in successful operation in Canadian potash shafts. Installed above the Prairie Evaporite salt formation at a depth of 3,000 feet, the sealant is preventing formation water migration into the salt and pressure build-up on the concrete lining of both production and service shafts. The salt protection rings are not under the hydrostatic pressure of the formation water.The chemical sealant in use has the unique property of imbibing water and swelling. •Therefore, any water at• tempting to flow by the seal ring actually produces a tighter seal.The purpose of this paper is to discuss the sealant and its properties and uses. Installation of the material and its operation in two Canadian mine shafts is described."

Jan 1, 1971

By J. K. Shaw

The science of low temperature engineering is well entrenched in mining. Uses for common cryogens, including liquid oxygen (LOX), liquid nitrogen (LN2), and liquefied natural gas (LNG) in the gas and minerals industries are reviewed. Potential future applications are discussed within the scope of mining, particularly in refrigeration and ventilation. The second part of this paper focuses on the Linde cycle, which is at the heart of most liquefaction plants. Steady state equations describing the mass and energy flows are presented. The paper concludes by explaining the concept of a wind powered Linde- Hampson cryogenic cycle and assessing, with scoping calculations, the technological feasibility of producing cryogens with an intermittent source of (renewable) energy.

Aug 1, 2013

By P. Nelson, B. Salt, J. A. Scott, H. Shang

ABSTRACT In a nickel smelting process, large amounts of off-gas emissions are generated, which can cause serious environmental and plant hygiene problems if not properly treated. With increasingly stringent environmental regulations, an enhanced understanding of well-controlled, off-gas cleaning systems is vital. In this paper, dynamic models for an industrial smelter, off-gas system tackling hazardous sulphur dioxide, carbon monoxide, and carbon dioxide are developed using mass continuity, momentum, and energy conservation laws. The effect of air in-leakage is explored under different operating conditions. The developed models provide an enhanced process understanding and a necessary basis for highperformance control analysis of smelter off-gas systems.

Jan 1, 2011

"The ventilation-related risks from mines with elemental sulphur include dust explosions, spontaneous combustion with emission of heat and toxic sulphur dioxide or hydrogen sulphide gases, reactions with nitrates, corrosion, acid water, and pyrophoric reactions with naked iron or other metals. Elemental sulphur will form explosive mixtures in air at lower dust concentrations and at lower ignition temperatures than coal or sulphide dusts. Potential controls include primary ventilation circuit design, control of dust deposition and static discharges, enclosing steel surfaces, inert stone dusting, FRAS ducting, humidifying the air, alternate stench gas, self-contained self-rescuers with goggles, careful siting of underground infrastructure, controls on explosives formulations and procedures, mining method selection, controls on surface temperatures and protection of equipment, careful materials selection for ventilation seals and changes to worker clothing and training.INTRODUCTIONSulphur (“Brimstone” in biblical times) is one of the world’s most important industrial feedstocks and is used in a wide range of chemical processes and industries. Until the early 20th Century, most of the world’s production of sulphur came from ‘conventional’ underground mines in Sicily (Demetra produzioni, 2006; Bellia, 2006). This was a hazardous activity. The Frasch solution mining process replaced traditional underground mining of sulphur until the late 20th Century. Most of the world’s production of elemental sulphur is now as a by-product from sour gas produced in petroleum refineries and natural gas installations (Anon, 1993). As such, there is considerable experience in understanding and managing the hazards of elemental sulphur in chemical plants and surface transport.Whilst rare, underground mines with high elemental sulphur contents (as a gangue mineral) create an unusual range of mine design and operational issues, including many ventilation-related ones. The key hazards from elemental sulphur include: primary and secondary elemental sulphur dust explosions, fires and burning (with emission of heat and sulphur dioxide or hydrogen sulphide gas), reactions with nitrates used in explosives, corrosion of steel and other metals, generation of acid water (especially at higher water temperatures), and pyrophoric reactions with naked iron (e.g., ground support, ladderways or underground fixed plant) or other metals including silver and copper (e.g., used in electrical components and equipment)."

Jan 1, 2019

By K. G. Davies, M. J. Royea

"A major program of pillar recovery at the Sullivan mine has been assisted for the past several years by a concerted series of rock mechanics investigations. The object of these investigations is to measure the parameters of rock behaviour which influence pillar mining. This quantitative information is then used in the design of mining methods appropriate for various conditions.Instrumentation to measure absolute rock stress, changes in rock stress and the gross deformation of rock masses has been developed. Various instruments are described, as are instrument evaluation procedures and typical test results. The data from underground measurement projects have been used to modify pillar extraction sequences along re-treat fronts. Rock mechanics information from individual pillars has been incorporated into the design of mining methods to suit particular circumstances."

Jan 1, 1968

By M. J. Latva-Kokko, T. J. Riihimäki

"Oxidation autoclaves are normally operated at elevated temperature and pressure. The improvement in kinetics is due to combined effect of temperature and partial pressure of oxygen. In this paper exclusive effect of pressure has been studied with a low grade sulphide ore at below 100 °C temperature. These studies are related to development of a novel tower-like reactor that utilizes hydrostatic pressure. Technology is designed to generate high amount of effective fluid volume for high solid content slurries with lower energy consumption and improved kinetics compared to normal atmospheric operation.INTRODUCTIONEconomical utilization of low-grade ores requires handling of enormous amount of material. This sets new requirements for process equipment in terms of size and energy efficiency. For example on the field of mineral processing this has lead to a six fold increase in the operating volume of mechanical flotation cells over the past two decades. Ore beneficiation methods like flotation greatly reduce amount of material that needs to be further processed in smelters or hydrometallurgical refineries. However with some ore types, such as nickel laterites and refractory gold ores, traditional concentration technologies cannot be utilized. Thus direct leaching of ground ore could be an attractive option. In many cases normal atmospheric tank leaching has traditionally been a non-feasible option mainly due to high capital and operational expenses induced by large amount of stirred reactors required. Main restriction for increasing reactor size to beyond 500 m3 has been mechanical load and power requirements set by mixing in cases when high dispersion efficiency of gas is required. THEORETICAL BACKGROUNDIn hydrometallurgical industry autoclaves are typically operated at elevated temperature and pressure. In many cases increase in operating temperature is the desired phenomena and improvements in kinetics are strongly related to that. Thus increase in pressure might be induced solely by water vapor pressure. However when gaseous feed is present, pressure itself has a strong effect on leaching kinetics for various reasons and its role should not be neglected."

Jan 1, 2012