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By Lyle F. Smith

With the demand for larger diameter raises under all ground conditions and the increasing price of drill rods and operating costs, it was evident that there was a need for a raise borer with a variable-speed drive and fast-response torque limiting control. The raise boring machine described in this paper was developed after several years of market research and discussions with mine operators and construction contractors. This paper discusses the Ingersoll-Rand raise borers with the solid-state controlled DC motor drives. These machines have gained wide acceptance in the five-year period since being placed in operation and are designed to accommodate the range of raise diameters and lengths most required today.

Jan 1, 1978

By I. Donohue, M. Pearson, E. Barrette

"This paper presents the technique and benefits of the finite element approach for designing the refractory lining in pressure oxidation autoclaves. One-dimensional equations are used to develop an initial refractory design. ANSYS Parametric Design Language (APDL) scripts are then used to build and analyse a more accurate three-dimensional finite element model to verify the refractory thickness, determine weld overlay requirements, and assess mechanical stability. The APDL scripts provide a cost effective means to quickly evaluate various boundary conditions and multiple designs to determine the optimal lining configuration and nozzle layout.INTRODUCTIONNew ore processing facilities demand increased capacity, requiring hydrometallurgy processes that have larger reactor vessels operating at higher pressure and temperature. Many pressure hydrometallurgy operations require vessels with an impermeable membrane and one or more courses of refractory or ceramic brick. The membrane provides corrosion protection for the vessel shell and the brick provides thermal protection for the membrane. Designing a refractory lining with an economic service life as a thermal barrier requires the refractory to be erosion resistant, chemically compatible with the process fluid, and mechanically stable. A fundamental understanding of the factors affecting the lining system is essential as designs move further away from the industry’s experience base.During basic engineering the refractory lining design is developed using one dimensional cylindrical conduction equations for heat transfer and classical hoop stress-strain relationships for determining mechanical stability. The results of the thermal calculations specify the refractory thickness that should prevent the membrane temperature from exceeding the design limit. Mechanical stability of the lining is determined by examining the sensitivity of lining stability with respect to various parameters. There are three criteria that must be satisfied to conclude mechanical lining stability:"

Jan 1, 2012

By J. L. Huisman

Bio(hydro)metallurgy is the latest development in the ongoing search for efficient and economic metal winning processes. In addition to bioleaching, other biotechnology-based applications are becoming more and more accepted. In this paper the THIOMET process for general effluent treatment is described. With this process, it is possible to produce sulfide on-site and on-demand and to use the sulfide to precipitate metals, even selectively when required. The process is ideally suited as a treatment to remove metals after, for example, an acid regeneration process. Another process is proposed that deals with stainless steel pickling bleeds. Such effluents typically contain nitrate, iron, nickel, chromium(VI) and other species. This one process handles these compounds, as well as other metals.

Jan 1, 2006

By J. Bakos

Solar Hydrogen Energy Corporation (SHEC Labs) recently constructed a pilot-plant to demonstrate a Dry Fuel Hydrogen Generation System that is powered primarily by sunlight focusing-mirrors. The pilot-plant consists of: A Solar Mirror Array and Advanced Solar Concentrator and Shutter System; and two thermo-catalytic reactors to convert Methane, Carbon Dioxide, and Water into Hydrogen. Results from the pilot study show that Solar Hydrogen generation is feasible and cost-competitive with traditional Hydrogen production. More than 95% of Hydrogen commercially produced today is by the Steam Methane Reformation (SMR) of natural gas, a process that liberates Carbon Dioxide to the atmosphere. The SMR process provides a net energy loss of 30 to 35% when converting from Methane to Hydrogen. Solar Hydrogen production provides a 14% net energy gain when converting Methane into Hydrogen since the energy used to drive the process is from the sun. The environmental benefits of generating Hydrogen using renewable energy include significant greenhouse gas and criteria air contaminant reductions.

Jan 1, 2005

By BRIAN HITCHON

Calcium, magnesium, bromide and iodide extraction from formation waters for use as industrial minerals has occurred in several countries, but not yet in Canada. Potential commercial brine fields exist in th e Upper Devonian Beaverhill Lake Formation of so uthern Alberta, and the Middle Devonian Elk Point Subgroup of north-central Alberta, f rom which calcium, magnesium and bromide are potential products. Iodide contents in fo rmation waters f rom the Upper Cretaceous Belly River Formation and the Lower Cretaceous Viking and Bow Island fo rmations in central and southern Alberta are at the lower range limit of commercial iodide-bearing formation waters elsewhere in the world. Available information is insufficient 10 outline potentially commercial areas in Alberta, but such info rmation can be most easily obtained f rom test borings for shallow natural gas. Lithium is not now produced commercially f rom formation waters but its content should be monitored in view of f uture increased demand for this metal.

Jan 1, 1984

By David G. Baskin

"THIS DEPARTMENT is unique in that it operates in the production stream and also provides an essential service. Its operating function consists of scheduling an ore train to haul 10,000 tons per day over 17.1 miles of track and switching all incoming and outgoing rail equipment on 2.2 miles of track at the minesite and 6.2 miles of track at the metallurgical site. The service it provides is traffic control of all incoming commodities and all outgoing concentrates, metals and acid by rail and truck, even extending to port and ship control for overseas shipments (Fig. 46). Although they cover many miles, the railroad and traffic department employees operate very efficiently, as indicated by the following organizational chart:Railroad and Traffic Superintendent ................ 1Railroad Supervisor .............................................. 1Assistant Railroad Supervisor ........................ 1Track Foreman ...................................................... 1Trainmen ............................................................... ... 4Switchmen ............................................................... 4Trackmen ................................................................ 10Traffic Supervisor ................................................ 1Clerk Steno ............................................................ 1Clerks ...................................................................... 3"

Jan 1, 1974

By Paul Toor

The operation of SAG mills is variable over time due to their continually changing liner shape, mass and subsequent load motion. However, this tends to be poorly accommodated in liner design and mill control, with only limited compensation made for this influence, usually in the first few weeks after a new liner is installed. With ever-increasing ore competency, increasing energy costs and decreasing ore grades, simplified design and operational approaches that compromise the achievable mill efficiency are no longer adequate. This paper presents a methodology that has been developed to measure and account for the changes in mill performance as the liner wears. This involves monitoring all liner profiles ? in other words the three-dimensional liner shape - over the life of the liner, then conducting controlled surveys at different stages of the liner wear life, and correlating the mill performance to the liner profiles. The measured liner mass is modelled to provide an ongoing meaningful load mass measure that excludes the liner mass.

Jan 1, 2012

By L. C. Johnston, J. N. Gills

This paper reviews the basic reactions of the blast furnace and the open hearth furnace, and then discusses the quarrying and sizing requirements of the limestone feed for each. Particular emphasis is placed on the lime-stone at Irish Cove, now being mined under an agreement between Scotia Limestone Limited and Dosco Steel Limited. The drilling and blasting operations are described, along with loading and haulage, plant flow, water supply, power supply and transportation facilities.

Jan 1, 1967

By J. E. Gill

"The Wasa Lake property is a block of about 1,640 acres in Beauchastel township, Quebec. Gold was discovered there first in 1936 in what is now known as the 'Southern area ( Fig. 1). Stripping and trenching were followed by 9,218 feet of diamond drilling in twenty holes. A number of good intersections were obtained, but their interpretation in terms of ore was difficult. A shaft was then sunk to 220 feet vertical depth. Thirteen hundred feet of lateral work and 543 feet of diamond drilling were completed at the 200-foot level before work was discontinued in 1938. Results up to this point had been just fair.Early in 1944, surface diamond drilling was resumed. The first hole cut material of ore grade in a strong shear zone 1,000 feet north of the old workings, and holes to the east and west showed this to be an extensive gold-bearing zone.In August 1945, a main working shaft was started. This has been sunk to 550 feet slope depth. A cross-cut at 390 feet vertical depth was driven to the ore zone and, by drifting and drilling at regular intervals, a length of 725 feet had been tested to December 31st, 1946 ( Figs. 1 and 2). The results check those from surface drilling quite closely.In the main zone, scoping widths from 8 to 40 feet and averaging about 25 feet are indicated. The grade after dilution should be about 0.15 oz. gold a ton and operation will probably start at 1,000 tons a day."

Jan 1, 1954

By Guocheng Pan

"Although many factors play roles in the estimation of recoverable reserves, smoothing effect and conditional bias are considered major geostatistical issues in the estimation. This paper introduces measures for smoothing effect and conditional bias, and provides insights into their relation to the estimation of recoverable reserves. Both smoothing effect and conditional bias are intrinsic to the information effect and kriging estimators. For a given level of drilling information, however, it is possible to identify the optimal search radius that minimizes conditional bias. Furthermore, it is also feasible to define variance correction factor for reduction of the smoothing effect from exploration block models. Both of these components are key to the accurate estimation of recoverable reserves. IntroductionThe accurate estimation of recoverable reserves is critical to decision making in different phases of feasibility study and mine planning. Much attention for improving the methodology of estimation has been focussed on the effect of the change-of-support (Parker, 1980; Dagdelen, 1996). For example, it is essential to make a volume- variance correction to the estimate of multiple indicator kriging (Hoerger, 1992). When the size of block, b, in the geostatistical model differs from that of selective mining unit (SMU), v, a volume-variance correction is warranted for the prediction of recoverable reserves.Most mining plans and decisions are made prior to the availability of high density blast-hole samples. In most mining operations, the true SMU grade Zv is unknown at the time of selection. Instead, the selection is based on the estimate Z v**derived from high density blast-hole samples within the deposit G. Nevertheless, the estimate Z v * of recoverable reserves in the stage of mine planning is derived from exploration data. At the end, the production result must be reconciled to the estimate Z v * . In other words, the selection is based on Z v** from blast-hole samples, while the final production figures are reconciled to Z v * from exploration drilling. For a given preselected cutoff grade z0, the actual mining panels will consist of the units having the estimated grade Z v** =z0 rather than the true grade Zv =z0. The difference between Z v** and Zv is usually of less concern."

Jan 1, 1998

By W. J. D. Stone

"For several years, the existence of a deposit of barite (BaS04) near Brookfield, Nova Scotia, has been known. A very large deposit of strontium (SrS04) near Sydney, Cape Breton, is a more recent discovery. Cape Chemical Syndicate has been formed to work the deposits. A five-million-dollar integrated mineral processing and chemical plant is planned for Sydney to produce various compounds of barium and strontium. The mineral processing plant includes the Jones Wet Magnetic Separator and will produce high-purity barite and celestite. These products will be processed further in the fine grinding plant and the chemical plant. The general project is described, covering the deposits, processing and markets."

Jan 1, 1969

By J. D. Little

"THE SALMO PROPERTIES of Canadian Exploration, Limited comprise forty-one Crown-granted mineral claims situated on Iron mountain between Sheep creek (on the north) and Lost creek, some eight miles southward from Salmo, in the Nelson mining division (see Figure 1). On these claims there are at present four operating mines. These are, from north to south, the Dodger, Feeney, and Emerald, all tungsten mines, and the Jersey, a lead-zinc mine, about 7,000 feet south of the Dodger. About midway between the Dodger and the Jersey is a fifth mine, the Emerald lead-zinc mine, which was the first producer in the area but has been inactive since 1926. The locations of the mines are shown in Figure 2.Records of prospecting and claim staking on Iron mountain -which owes its name to the presence of large iron-stained outcrops -go back to 1895. The first recorded owner of the claims that form the old Emerald lead-zinc mine was John Waldbeser who, in 1908, did considerable work and produced 426 tons of lead ore valued, at the then price of lead, at $7,000. This ore was chiefly lead carbonate and was taken from the surface outcrops of two bands of ore that form the Emerald orebodies. In 1909, the Emerald was the largest lead producer in the Nelson mining district."

Jan 1, 1953

By A. E. Boudreau

It has long been recognized that platinum-group-element (PGE) deposits in layered intrusions preferentially occur in intrusions that crystallized from high-Mg parent magmas. Recent studies suggest that evaluation of any given intrusion for economic PGE potential should also include assessment of the PGE, sulfur and chlorine concentrations in the cumulates and potential parent liquids. PGE: Magmas that contain relatively abundant Pt and Pd are the best candidates for forming economic deposits. Although analyses of coeval sills and dikes are the best indicators of primary magmatic PGE concentrations, analysis of the cumulates themselves is also valuable. For example, within the Stillwater complex, background PGE values in cumulates from the ultramafic sections of the complex contain, on average, several 10s of ppb Pt and Pd. Background concentrations of this order are suggestive that the magma was not depleted in the PGE. Sulfur: Conventional petrogenetic models for the formation of PGE deposits in layered intrusions require the PGE to have been concentrated during a magmatic sulfide-saturation event. In contrast, some hydro thermal models suggest that sulfur and the PGE were mobilized from footwall cumulates by upward-migrating, high-temperature hydrothermal fluids. Both models suggest that significant PGE deposits are likely to occur at and below the level where stratigraphic increases in whole rock sulfur concentrations occur. Chlorine: In both the Stillwater and Bushveld complexes the cumulate sequences below the major PGE-bearing zones contain anomalous Cl-rich apatite. The chlorapatite component of apatite in these rocks may exceed 40% and, in the Stillwater complex, typically exceeds 90%. It is stressed that pristine igneous mineral analysis and not whole rock data be used, as whole rock Cl concentrations may be affected by very localized (grain boundary), low-temperature alteration. Intrusions that crystallized from high-Mg, high-Cl magmas appear to have the best potential to host significant PGE deposits.

Jan 1, 1995

By A. Varma

Successful technology commercialization occurs when a company is focused on creating shareholder value by providing a reliable product at a price point attractive to the market, while at the same time maintaining strict control of its internal cash burn rates. Developing a technology platform and a market platform are equally important in the commercialization of new technologies such as fuel cells. This paper will discuss some of the key barriers that may prevent successful market entry for emerging and disruptive technologies, such as: R&D priorities, supply chain / manufacturing issues, materials, cost reduction strategies, customer needs, developing a market pull strategy, institutional barriers such as existing regulatory/approvals processes and/or current design/purchasing practices, product reliability and resilience, and finding the right path to market. SDTC is an arms length foundation that aims to financially support the successful market entry of emerging and disruptive technologies that can provide significant environmental benefits to Canada. The fuel cell industry, which represents one such technology, is at a critical point in its evolution where market receptivity and the technology platform are converging to potentially create significant customer advantages for fuel cell products being developed today. Since its inception in 2001, SDTC has received over 850 business cases from which it has identified successful strategies to overcome the noted barriers to commercialization. While maintaining commercial confidentiality, the SDTC database will be mined to: Identify specific success stories that have overcome various barriers and discuss their strategy; Identify specific fuel cell related industry experiences that hinder successful market uptake. The general attributes and trends of successful technology developments identified in this paper will hopefully provide guidance to technology developers and prepare them to successfully tackle the next set of hurdles on the path to commercializing their technology, once they have proven their technology works in the laboratory.

Jan 1, 2005

By Oberlando Gonzalez, Claudia Serna, Andrea Alzate, Esperanza López, Maria Holuszko

This paper presents a systematic approach on gold recovery from electronic waste (e-waste) using ammonium persulfate. This process was developed as a response to the lack of hydrometallurgical systems capable of separating gold from its metallic substrate without material grinding, with minimum formation of pollutants, and achieving a lower reaction time. Computer memory boards, electronic processors and electronic pins and contacts were analyzed to determinate base metals (Ni, Fe, Cu) and gold (Au) using microwave plasma atomic emission spectroscopy (MP-AES). An aqueous commercial grade ammonium persulfate with oxygen and pressure was used to produce the persulfate anion (S2O82-) and the oxidative sulfate ion (SO42-), which partially oxidized and leached the base metals breaking the Au-Ni-Fe-Cu bonds and allowing gold to be recovered in its original non-leaching state. The influence of the oxidative parameters was evaluated using full factorial (FF) and central composite designs (CCD) with response surface methodology (RSM) and first and second order models were developed. Using RSM allowed to obtain a faster recovery of gold, minimizing the agent consumption. The findings presented suggest that optimized quantities of ammonium persulfate, oxygen, pressure, temperature and liquid solid ratio could be used for selective oxidization of the base metals and to extract more than 96% of gold from e-waste.

Jan 1, 2017

By Louis Frost

The coal-mining industry of Nova Scotia, particularly of the island of Cape Breton, today faced as no other industry with economic problems calling for progressive engineering with production on an economic basis, must soon enter upon a phase of reorganization wherein all factors conducive to the cost of producing coal relative to the prolongation of the life of the collieries with the ultimate winning of the maximum submarine area must be closely reviewed. Bearing this in mind and applying the process of elimination to coal-mining costs generally, we are left with only three channels through which we may approach the problem of cost reduction in producing coal: (a) intensive mechanization (b) reduction in the cost of labour (c) reduction in the cost of materials. Assuming that mechanization has reached an economic stage and that labour costs have reached an economic limit, we must turn our attention to the general material costs, which may be classified as 'live' and 'dead' costs. The former take in all things which can be accredited with a fractional depreciation and written off the balance sheet over a period of years. On the other hand, the ?dead'costs-of which the cost of supporting the underground workings form part must be completely written off: for these, no return may be expected, other than the economic return in the reduction of the cost per ton of coal produced.

Jan 1, 1928

By J. A. Vezina

The effects of particle size distribution on metal extraction have been determined from pressure leaching Renzy Mines Limited concentrate with oxygen. Using a pulp density of 30 per cent solids, an oxygen pressure of 80 psig, a temperature of 230°F, a grind of 2.5 hours and a retention of 8 hours resulted in the almost complete dissolution of the nickel and the cobalt and the decomposition of over 96 per cent of the chalcopyrite finer than 20 microns. Only 11 per cent of the chalcopyrite coarser than 20 microns was reduced to smaller than 20 microns.

Jan 1, 1973

By J. C. Murray

Introductory: In dealing with a topic so large, one that involves such a multiplicity of details, and that also has certain controversial aspects, it is quite impracticable within the limits of this article to touch upon many most interesting phases and incidents. Also, to bring out the actual truth, it is necessary to make certain categorical statements. The writer believes that all such statements made here-under are supported by facts. Again, however, it is out of the question to cite all the proof. The writer, therefore, will gladly answer any pertinent criticisms or questions and thus supplement the unavoidable brevity of this paper. Controversial points will take care of themselves. Historical: For present purposes the history of gold mining in Nova Scotia may best be summed up in a very few paragraphs, in some of which the writer quotes freely from recent reports compiled by himself. The first material discovery of gold was made in the year 1860. As this and rapidly succeeding discoveries were looked upon as bonanzas, the claims were fixed at a size of 20 by 50 feet, and a yearly rental of $20 was charged. Later the claims (areas) were increased in size to 50 by 150 feet. In the year 1866 a temporarily successful company, so we are informed by a contemporary writer, owned a mill and mining plant worth $6,000. As this fact is cited with admiration, it is apparent that most of the mining and milling must have been done in a very primitive manner indeed.

Jan 1, 1926

By K. Mirkhani, P. Gebski, W. Ying

The campaign life of an industrial metallurgical vessels strongly relies on the quality and quantity of the refractory lining. An operating furnace or converter refractory lining can be assessed either by thermal modeling or by acousto ultrasonic-echo (AU-E) technique or a combination. AU-E is a Non-Destructive Testing (NDT) stress wave propagation technique that has been utilized on a wide variety of smelting vessels for over 12 years with good success. AU-E can determine the thickness of remaining refractory lining, estimate the thickness of build-up or accretion, detect and locate metal penetration and impregnation into the lining, and identify hydrated or cracked areas of refractory. This paper details the AU-E principles, equipment and recent improvements to the data analysis to further improve speed and accuracy. In addition, the paper discusses the AU-E accuracy and limitations through a diverse and vast array of practical examples including a comparison with thermal modeling and physical measurements.

Jan 1, 2011

By M. Bavand-Vandchali, F. Golestani-Fard, S. Khalili, S. Rowshanfekr-Fallah

In the secondary metallurgy of steel, the availability of ladles plays an important role in decreasing the production cost. The refractory lining, therefore, should satisfy optimized quality to grant higher heats. This paper reports the results of an investigation carried out in Iranian Mobarakeh Steel Company in order to increase the lining life of ladles by employing different types of MgO C and Al203 - Mg° - C. The zoning concept was used in replacing the conventional refractories either in slag line or the lower parts of ladle. The number of heats could be improved to almost two times as before. The results are explained in terms of refractory quality as well as zoning approach. The economical impact of this improvement will also be analyzed.

Jan 1, 2004