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By William E. Roscoe

"Mineral exploration properties are those on which an economically viable mineral deposit has not yet been discovered. Such properties are bought, sold, optioned and joint ventured on the basis of their perceived potential for the existence and discovery of a viable mineral deposit. The intrinsic value of an exploration property is therefore based on the exploration potential. One measure of the exploration potential is the amount that can be justified to spend on exploration for a viable deposit.The appraised value method uses a cost approach to value exploration properties. It is based on the premise that an exploration property is worth the meaningful past exploration expenditures plus warranted future costs to test remaining exploration potential. Results of past exploration work are analyzed in order to retain only those past expenditures that are productive in terms of identifying remaining potential. Warranted future costs comprise a reasonable exploration budget to test that potential.INTRODUCTIONThe purpose of this paper is to describe a cost approach to the valuation of mineral exploration properties and to provide some valuation examples. The particular cost approach described is the Appraised Value Method, which is best applied to mineral properties at the exploration stage.At present there are no comprehensive regulations or guidelines in Canada which specify what approaches and methods to use for the valuation of mineral properties. In this paper, the Appraised Value Method described is one method that the writer considers to be accepted industry practice for mineral properties at the exploration stage.Mineral properties are valued for a number of reasons, including mergers and acquisitions, non arm's length transactions, pricing of initial public offering of stock, support for property agreements, litigation, expropriation, and insurance claims."

Jan 1, 2003

By R. Khanna, K. Hyun Ko, A. J. Berkovich, J. Hook

"The co-pyrolysis of synthetic polymer polyethylene terephthalate (PET) and agricultural wastes (naturally occurring polymer-macadamia nut shell) was investigated in the temperature range 473K to 1273K using a horizontal furnace with an aim to understand their thermal degradation under isothermal conditions. In-depth characterization of pyrolysis residues was carried out using x-ray diffraction (XRD) and solid state nuclear magnetic resonance (NMR) for carbon structure, and through determination of the concentration of unpaired electrons using electron paramagnetic resonance (EPR). In previous studies, it has been found that PET thermally decomposes ~ 650K-700K, releasing (~80 wt % of initial weight) gaseous products due to random chain scission. In the case of macadamia nut shell, three types of byproduct can be obtained from pyrolysis: char, tar and gaseous products. In the co-pyrolysis of macadamia nut shell with PET in 50-50 wt% ratio, total product weight ratio could be modified with the addition of PET acting as a hydrogen source. This is because a recombination of thermal cracking products of cellulose could be suppressed by hydrogen from PET, which will later lead to an enhancement of tar formation. In addition, pyrolysis around 673K is sufficient for bond cleavage to occur in cellulose and lignin leading to the formation of negatively charged activated carbon with high surface area, providing bonding sites for volatiles evolving from PET. Therefore the co-pyrolysis may be able to enhance the product yield (tar/char/solid carbon residue) along with a reduction in the release of gaseous products. During the co-pyrolysis, temperature was found to have a significant influence on the kinetics of thermal degradation and solid residual by-products after co-pyrolysis.INTRODUCTIONPlastics are being used worldwide in a wide range of applications in the modern society; their usage has resulted in increasingly a massive waste problem. The production of most synthetic plastics requires hydrocarbons that are produced from petrochemicals derived from fossil oil and natural gas, a non-renewable source (Speight 2011). Currently, plastic manufacture utilizes ~4% of world oil and gas production, and it is expected to drive further increases in petroleum demand by 1-2% due to their large volume of manufacture (Hopewell, Dvorak et al. 2009). Landfilling and incineration of plastic waste are the two main routes to plastic waste management (Encinar and González 2008). In Australia, only 10% of waste plastics were recycled in 2006 (White and Hyde 2011). This means that large amount of fossil fuels from plastics has either been simply burned for energy recovery or buried in the ground. There is an urgent need for developing alternative avenues for recycling waste plastics. Our group at UNSW has carried out extensive research on the recycling of waste polymers as carbon resource in steelmaking including slag foaming and carbon dissolution from waste plastics into liquid steel at 1600°C; the effect of basic plastic characteristics such as chemical composition, structure, bonding network etc. was examined (Sahajwalla, Rahman et al. 2009)"

Jan 1, 2012

By E. Dernedde

A few studies have suggested that the rate of adsorption of hydrogen fluoride on smelter grade alumina is determined by kinetic factors. However, no performance equation for dry scrubbers has appeared in the literature so far. Experimental data from a pilot dry scrubber with co-current flow were compared with results of kinetic models of adsorption, film diffusion and pore diffusion. The pore diffusion model was deemed the most appropriate. It was transformed into a performance equation for steady-state operations of dry scrubbers by the inclusion of the alumina recirculation. Operating results of industrial dry scrubbers with co-current flow were successfully evaluated by means of the performance equation. The average fluoride content of the alumina was also estimated by using the pore diffusion model.

Jan 1, 2011

By W. Standifird

"Cohesive fracture is a mechanical model widely used for modeling quasi-brittle fracture in rocklike materials. This work discusses use of this model to simulate quasi-brittle fractures generated by injection stimulation during the process of cuttings reinjection in West Africa. Cuttings reinjection is an engineering practice used for disposal of drilling waste. During this process, hydraulic fractures are created at the target formation and milled cuttings are injected with fluid. In practice, this process must remain in compliance with environmental regulations and zero-discharge policies. The purpose of this study is to determine the following factors of injection design for a field in West Africa: (1) pumping pressure capacity required to successfully perform the injection and (2) the injection rate for injection performance and the value of fracture width under injection.A simplified three-dimensional (3D) finite element model (FEM) was built. A poroelastic plastic damage model was used for simulation of the cohesive crack prorogation within the target formation. For simplicity, fracture development in both horizontal and vertical directions was simulated separately. In this way, the computational burden for one calculation was reduced to a reasonably low level, without losing accuracy of the model. Loads of the model include fluid injection and gravity, which balances the initial geostress field. Various values of injection rate were used in these calculations to determine the most reasonable value of injection pressure. The capacity of pressure of a pumping device was determined using this optimized value of injection pressure.Results in values of width and length of fractures created by the injection are presented. Injection pressures at bottom-hole (BHP) corresponding to each value of injection rate are also given. Numerical results for fracture generation and propagation in a horizontal direction were visualized. The pumping pressure capacity required to fulfill the cuttings reinjection work was determined based on the numerical results of optimized injection rates and pressure. The fracture width was determined using the given pumping pressure. The length and height of the fractures was determined using pumping pressure along with the required volume of cuttings waste to be disposed of into the formation.This work presents a case study of 3D finite element modeling of hydraulic fracturing generated by cuttings reinjection. The results of the optimized injection rate and pressure provide a best practice and a useful reference for cuttings reinjection analyses in this region."

Jan 1, 2015

By Kaiwen Xia, Bibhu Mohanty, Per Svedensten, Sheng Huang

"The mechanics of crushing and grinding operations in mining and excavation processes has been investigated in a laboratory simulation study. It employs a multi-particle bedded rock target, which is subjected to multiple impacts. The impact set-up consists of a Hopkinson pressure bar and a Piston-holder system. The apparatus, employing a 38 mm diameter pressure bar, was used to apply varying but calibrated dynamic loading force on the rock particles. The energy consumed by the sample during fragmentation was determined by considering the energy carried by the incident wave and the reflected wave. The Pistonholder system is used to hold rock samples and to recycle fragments after each test for particle size analysis, for single as well as multiple impacts. The feed size selected was in the range of 9.5 to 12.7 mm for all rock samples, and the impact velocity was set at 14 m/s. Two strong granitic rocks and a relatively weak limestone were the target rocks. The resulting particle size distribution after each set of impacts, ranging from single to 10 consecutive impacts, were analyzed, and various size distribution functions (i.e. Rosin- Rammler, Swebrec, Grady and Gilvarry functions) were fitted to compare their suitability in predicting the fragment size distribution for each rock type. INTRODUCTIONCrushers are widely used in the mining industry all over the world. Understanding fragmentation behaviour of rock under crushing process is fundamental to improved productivity and efficiency in mining operations. This is particularly so as all subsequent size reduction processes such as crushing and grinding are far more energy intensive than the initial blasting process employed in breaking of in situ rock. A considerable body of experimental studies exists on the behaviour of rock crushers for specific rock types in order to aid in the design of various types of crushers. However, these studies are mainly site specific, that is, the results are largely empirical, and the fundamentals of fracture process that lead to size reduction have not been dealt with adequately. Most such studies have attempted to link the input parameters, such as feed size and crusher parameters, with output particle size, and global energy expended in the process. However the physical mechanism of crushing process is still not well understood. First of all, the energy consumed by the rock sample is hard to calculate during standard crushing or grinding tests; secondly, multi-particle test is hard to perform in the laboratory due to irregular shape of the subject rock sample. In This paper, describes a laboratory crushing apparatus for multi-particle rock samples, with sufficient control of the energy expended in the process, with a view to relate creation of new fracture surfaces in the size reduction process."

Jan 1, 2015

By R. Khettabi

The mechanical, thermal and bioproperties of titanium alloys allow their wide use in different industries. Compared to aluminum alloys, titanium alloys are very tough, making them that much more difficult to machine than aluminum alloys. Most studies conducted on these types of materials have mainly covered and made comparisons in terms of cutting speed, cutting force and mechanical properties. Recently however, their sustainability and environment parameters have begun to attract significant interest, and it has been found that machining processes generate particles that can be harmful for health and the environment. In this paper, particle emission is investigated during the turning of the titanium Ti6A14V and 6061-T6 aluminum alloys.

Jan 1, 2011

By E. S. Moore

In order that a logical conclusion may be reached regarding the possible occurrence of commercial iron deposits in Canada it is necessary to consider some important producers found elsewhere on this continent. A study of such deposits reveals the fact tl:~at a number of distinct types are producing large tonnages of ore. These types may be classified according to origin and occurrence as follows: (1) Bedded sedimentary deposits. (2) Contact metamorphic deposits. (3) Residual ores. (4) Lenses in metamorphic rocks and m some cases of uncertain origin. In addition to the types listed there are other deposits which have contained or do contain considerable ore and they either have not been worked on a large scale or they have been nearly exhausted. These include the following types: (1) Magmatic segregations. These are mostly titaniferous magnetites. (2) Dikes of magnetite of igneous origin. (3) Bog and lake ores in glacial drift. (4) Black sand placers.

Jan 1, 1925

By G. Stenning

The paper outlines the need for high-volume ventilation in a uranium mining operation based on the design to meet environmental requirements for dust, radiation and diesel equipment. Mining methods in a highly mechanized operation, a key factor in design, are discussed. The construction and installation of major intake and exhaust fans are described briefly, together with the development of the mine airways and distribution system. Controls in the form of doors and bulkheads are important considerations in planning. Finally, the need to lower ventilation requirements in response to increasing power costs will result in future improvements.

Jan 1, 1979

By Yan Jie

A series of production technologies are described for gold recovery from complex gold concentrate blended with copper concentrate treated in the SKS smelting process comprising: 1) Feed preparation and proportionate feeding of complex gold concentrate and copper concentrate; 2) SKS smelting gold recovery operation and process control technology developed based on reaction mechanism, process simulation and slag formation optimization study; 3) a dry-process quenching arsenic collection technology developed during de-bottlenecking severe restriction of SO3 in the off-gas on As collection system by suppressing and eliminating SO3 in off-gas as a result of optimizing SKS smelting process conditions and spraying caustic soda absorbent so as to reduce off-gas dew point temperature; 4) electrorefining of impure anodes; 5) technology for recovering such precious metals as Au, Ag, Pt, Pd, etc. from high-Sb copper anode slime produced as a result of gold recovery from complex gold concentrate by using SKS smelting process. INTRODUCTION Gold concentrate resources in China are mainly found in Shandong province, Henan province and the Inner Mongolia Autonomous Region, etc. Currently, recovery of gold is based on pre-oxidation (roasting) cyanide leaching process. This process produces a large amount of cyanide-containing wastewater, cyanide leaching residue and relatively high SO2-bearing flue gas during production, which can cause increasingly more serious environmental pollution issues. Besides, this process route suffers from a relatively low precious metals recovery (70–80%) found when treating refractory gold concentrate and carbon-bearing gold concentrate. These issues have severely restricted the development of the precious metals processing industry in China.

Jan 1, 2019

By J. Graham Eby

"This paper describes the development and some typical applications of Wemco's large-capacity flotation machines, the No. 120 and the No. 144, with volumes of 300 and 500 cubic feet, respectively. During the 1960's, it became obvious that low-grade orebodies would be mined at high tonnage rates - plants and grinding mills would be larger, which would create a demand for larger flotation equipment. To meet this demand, Wemco developed a single-mechanism, 300-cubicfoot cell, having five times the volume of the standard No. 66 cell. The average production rate of the No. 66 cell on porphyry copper ore was 100 tpd per cell; and it was our intention that the No. 120 (300-cu. ft) cell would handle 500 tpd per cell, with at least equal metallurgical results and power consumption per ton. The success and industry acceptance of the No. 120 cell has since led to the development of a larger cell, the No. 144, having a volume of 500 cubic feet."

Jan 1, 1972

By C. G. Anderson

Industrially proven and applied nitrogen species catalyzed (i.e. NSC) acidic pressure leaching has been utilized to treat a number of ores, concentrates and recycled materials. This versatile technology offers many advantages including low temperatures, low pressures, low capital costs, low operating costs, faster throughput and less costly materials of construction than conventional pressure oxidation. This paper will elucidate the application of this technology for production of gold, silver, palladium, rhodium, zinc, germanium, gallium, cobalt, copper and nickel. Recycled material applications will also be elucidated. In addition, details of an application for treatment of a refractory chalcopyrite copper and gold bearing ore will be presented and pertinent economics discussed.

Jan 1, 2004

By Anthony T. Eyton

Intelligent Systems: Advantages for Mining ? Increased safety (reduced risk to workers) ? Increased productivity (reduced downtime) ? Reduced maintenance costs ? Customized solutions for different mines ? Growing acceptance among mine managers A Typical Precarn Project ? Meets definition of intelligent systems ? Involves at least two Precarn members ? a technology developer partner and a user partner ? in a true collaboration ? Involves at least one university and may have various other players ? Leads to a demonstrated prototype ? Costs $2-4 million, and lasts 12-30 months ? Gets up to 40% of its funding from Precarn (max. $1 m) ? Produces new intellectual property -- owned by the project team

May 1, 2002

By J M. Anderson

The cable belt conveyor installation at Craigmont Mines Limited, Merritt, B.C., has the greatest one-stage vertical fall of any conveyor installed overland in Canada. Since the late summer of 1961, this conveyor has carried more than 5,000,000 tons of copper ore from open pit to concentrator site. When the conveyor is loaded, the drive motor acts as an induction generator, delivering power to an external circuit. This paper covers the selection, the operation, the performance statistics, and the installation and operating costs of this conveyor system. Introduction T HE Craigmont mine is located in the south-western interior region of the Province of British Columbia, approximately 240 miles northeast of Vancouver. A moderate climate, good roads, service by the Canadian Pacific Railroad, power from the British Columbia Hydro Authority, gas from the nearby main line of the Inland Natural Gas Company and close proximity to the village of Merritt provide a favourable location for this mining operation. The ore occurrences at Craigmont have a vertical extent of 1,500 feet,

Jan 1, 1965

By S. P. Lowe

Flotation testing of Flin Flon ore was started in the Denver laboratory of Complex Ores Recoveries Co. in March, 1926. There had been a considerable amount of flotation testing previously which had shown possibilities of success, and it was felt that, with the increased knowledge of flotation and the comparatively new reagents then available, flotation held out the best prospects for a successful commercial treatment of this ore. There remained available for this experimental work a small amount of the rejects from a thorough sampling of the mine and some ore from the mine dump.

Jan 1, 1930

By A. N. May

"This paper describes the present approach of the Mines Branch to the problem of measuring the stress condition in the interior of rocks surrounding underground openings. An instrument, which will be referred to as a stressmeter, has been developed at the Mines Branch to measure un-directional stress changes in absolute units. There are two modes of operation of this stressmeter. It can be regarded as a fixed instrument, in which case it is installed at the end of a diamond drill hole and left in position to record any subsequent stress changes taking place. Alternatively, three of the stressmeters can be used in conjunction with a trepanning opera-tion to allow the existing stress condition to be determined. The initial laboratory work and subsequent experiences in the field with the stressmeter are described. All the field development work on the stressmeter was made possible through the co-operation of Canadian Refractories Limited, Kilmar, Quebec."

Jan 1, 1960

By M. A. Bergougnou, I. Inculet, K. I. Burgess

This paper describes the electrostatic methods of separating various minerals, reviews the principles of fluidization and outlines the technique of electrostatic sorting in fluidized beds. The application of the method to the benefication of coal is emphasized.

Jan 1, 1970

By B. Lafrance, C. J. Beaumont-Smith, L. R. Jones

"Abstract - The Burnt Timber gold deposit is located in the Paleoproterozoic Lynn Lake greenstone belt of the Trans-Hudson Orogen, Manitoba. The deposit occurs along the Johnson shear zone, and is hosted by enriched and depleted tholeiitic volcanic arc basalts cut by feldspar porphyry dikes. The Johnson shear zone is a regional, belt-parallel structure characterized by the intensification of the regional S2 foliation. At the Burnt Timber deposit, S2 is folded by centimeter- to meter-scale, Z-shaped, F3 chevron folds that have an axial planar S3 crenulation cleavage. Within the 20 to 30 m-wide core zone of the shear zone, S2 and F3 are transposed parallel to S3 and the volcanic rocks are strongly sheared parallel to S3. The presence of a steeply plunging stretching lineation, together with dextral shear sense indicators along both S2 and S3 on horizontal surfaces, suggest that the Johnson shear zone is a dextral transpression zone. Gold was introduced in pyritic, biotitic, and carbonatized mafic volcanic rocks along the core of the shear zone. Mylonitic mafic volcanic rocks contain localized high-grade zones (=10 g/t Au) that differ from wider carbonatized, low-grade zones (<3 g/t Au) by the presence of deformed gold-bearing quartz-pyrite veins. High-grade zones are also associated with swarms of quartz-pyrite veins that cut across sericitized and carbonatized feldspar porphyry dikes, which acted as brittle, competent bodies during shearing. Gold deposition in the high-grade zones was controlled by the channeling of hydrothermal fluid along the core of the shear zone during shearing of the volcanic rocks, and brittle fracturing of the porphyry dikes. Sommaire - Le gîte aurifère de Burnt Timber est situé dans la ceinture de roches vertes Paléoprotérozoïque de Lynn Lake dans l’orogène Trans-Hudsonien, au Manitoba. Ce gîte est situé le long de la zone de cisaillement de Johnson et est encaissé dans des basaltes tholéiitiques d’arc enrichis et appauvris recoupés par des dykes porphyriques. La zone de cisaillement de Johnson est une structure régionale parallèle à la ceinture de Lynn Lake caractérisée par une intensité accrue de la foliation régionale S2. Au gîte de Burnt Timber, S2 est affectée par un plissement F3 en chevrons en Z d’échelle centimétrique à métrique associé à un clivage de crénulation de plan axial S3. Dans la zone centrale de 20 à 30 m de largeur au sein de la zone de cisaillement, S2 et F3 sont transposés parallèlement à S3 et les roches volcaniques sont fortement cisaillées le long de S3. La présence conjointe d’une linéation d’étirement à forte plongée et d’indicateurs cinématiques dextres sur les surfaces horizontales S2 et S3 suggère que la zone de cisaillement de Johnson est une zone transpressive dextre. L’or a été mis en place dans des volcanites mafiques altérées en pyrite, en biotite, et en carbonate au coeur de la zone de cisaillement. Les roches volcaniques mylonitiques présentent des zones aurifères locales à haute teneur (=10 g/t Au) qui diffèrent des zones à basse teneur (<3 g/t Au) par la présence de veines de quartz et de pyrite aurifère. Des zones à haute teneur associées à des essaims de veinules de quartz et de pyrite sont aussi notées dans des dykes porphyriques à plagioclase altérés en séricite et en carbonates; ces dykes se sont comportés comme des corps compétents durant le cisaillement. La déposition de l’or dans le zones à haute teneur a été contrôlée par la circulation du fluide hydrothermal au coeur de la zone de cisaillement durant la déformation des roches volcaniques et la fracturation des dykes porphyriques."

Jan 1, 2006

By Richard S. Allen

"The casual visitor is not apt to think of the Adirondacks as a one-time hive of mining and manufacturing activity. However, where there are mountains there are usually minerals and northern New York State is no exception.The Adirondacks are a rocky shield, a great stone cap pulled down over what is now northern New York. The bedrock consists of layered metamorphic rocks which were once sandstones or limestones on the bottom of a shallow sea that covered the region 1000 million years ago. The highlands are composed for the most part of the igneous rock anorthosite. Ancient earth upheavals at temperatures of at least 750°C mixed molten masses of anorthosite and the minerals it contained with the older metamorphic rock, resulting in deposits of iron-titanium oxide s, red garnet and other valuable minerals. Of these, the most readily recognizable was iron.The first hint of the existence of iron ore in the Adirondack Lake Champlain region of upper New York State seems to have come from a Swedish naturalist, Peter Kalm (1716-1769), who travelled through French Canada and visited the military outpost of Fort St. Frederic in 1749. In July of that year, Kalm wrote:""Among the kinds of sand which are found on the shores of Lake Champlain; one is black and the other garnet-colored... and they sparkle when the sun shines. All the grains of this sand without exception are attracted to the magnet, the uppermost or black sand being about a quarter inch deep...""Concerned primarily with the fur trade, the officers and men who occupied this remote bastion of La Belle France were apparently unaware of the industrial and commercial possibilities beneath their feet. No deposit of iron was then known to exist any closer than the Three River s area in Lower Canada."

Jan 1, 1983

By G. G. W. Thom, A. A. F. Schuldt

At The Steel Company of Canada, Limited, iron oxide dust from the basic oxygen open hearths is being collected by means of electrostatic precipitators. The utilization of this dust, which has been hampered by the presence of zinc and lead oxides and sulphur compounds, is made possible by direct reduction in a rotary kiln. The description of the dust collection system and the results of kiln tests are presented.

Jan 1, 1966

By J. J. Baz-Dresch

"The Cannon Mine, a joint venture between Asamera Minerals (the operator) and Breakwater Resources, is located in the centre of Washington state at the eastern base of the Cascade Mountains. The mine complex is located three blocks south of the city limits of Wenatchee, part of an urban area with a total population of 47 000. The closest residence is 350 feet from the mine portal.The B-Neath zone is a narrow, high-grade, downward extension of the southern tail of the mine&apos;s main ore body, the B-North zone. It also underlies the northernmost portion of the B-West zone (Fig . I) . The ore is usually reasonably competent but completely surrounded by very weak rock consisting of shear zone and unsilicified sandstones and siltstones.The zone has maximum dimensions of 420 ft in thickness, 500 ft in length , and 200 ft in width . The economic reserves extend from the 70-ft elevation (elevation above sea level) to the 630-ft elevation and consist of about 1.3 million tons of geologic reserves (proven and probable) at an average grade of 0.33 ounces per ton.Acquisition and ExplorationInitial DiscoveryThe initial discovery of the B-Neath zone was made by Tenneco Minerals during July through September, 1984. Their 22-hole surface drilling program consisted of 18 200 ft of drilling. Tenneco Minerals had acquired the 91/2 acre lease from United Mining Corporation.Asamera Minerals subsequently purchased Tenneco&apos;s lease in July, 1985; Tenneco retained a royalty position which was later purchased by Echo Bay Mining.Follow-up drilling by Asamera Minerals consisted of both surface and underground drilling. Eight surface holes (7200 ft) were drilled commencing in December, 1985. Following evaluation of the geologic data, an access drift was driven on strike along the top of the ore zone on the 500 level. Diamond drilling from this platform consisted of 17 200 ft in 79 holes."

Jan 1, 1990