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By Y. Mercadier, M. Ait-Ali, M. Dostie

"This paper presents the results of an analytical study to assist in the design of blast furnace tuyeres, including a prediction of the heat transfer process.IntroductionA blast furnace tuyere must be made of a material which must con serve its geometric and structural integrity in the environment of the fire-ball of the furnace. It must be cooled by a fluid forced through its internal cavities in such way as to keep its maximum temperature below the allowable limit. The prediction of the convective heat transfer coefficient inside the tuyere is of great importance in the design of new tuyeres with increased service life. We have developed a computer program which can predict the convective heat transfer coefficient for two-phase flow. This paper shows how the program work s and how it can be used for the numerical simulation of tuyeres.To simulate the h eat transfer conditions in water-cooled tuyeres, one has to predict:a) The heat flux (radiation and convection) generated by the combustion gases. This was evaluated using the single-zone gas-furnace model. This model yields results which are of the right order of magnitude. A more fundamental study of radiation heat transfer based on combustion and gas concentration s will be reported in a future publication.b) The local convective heat transfer coefficient at all points with in the tuyere.Prediction of the Convective Heat Transfer CoefficientTo calculate the convective heat transfer coefficient for refrigerant stream, semi-empirical correlations developed by the nuclear industry were adopted. These correlations permit us to analyze the entire range of the convective boiling range, as shown in Table 1. Our first attempt, with a single-phase flow correlation, has shown the need to take nucleate boiling into account."

Jan 1, 1982

By Z. Pilecki

This work concerns the identification of weak zones in the structure of a rock mass endangered by outburst of gases and rocks in the Rudna copper ore mine at greater depths (approximately 1200 m). A special methodology has been undertaken for the recognition of that threat in the wake of an outburst in the mine in 2009. No similar phenomena have been previously recorded in KGHM Polska Miedz copper ore mines. The research described in this paper was carried out in the new part of the deposit prepared for mining. Geophysical methods were used: seismic tomography and borehole ground penetrating radar (BGPR), along with particular identifications using geological engineering methods. In the researched area, Permian layers of sandstone and shale clay (Weissliegendes formation) and of Zechstein dolomite (top of Rotliegend formation) and anhydrite occur in the copper ore deposit. The rock layers are characterized by variable thickness and intensity of mineralization, varying internal structure, and local fracturing containing different gases and water. It is assumed that accumulation of gases occurs in the tectonically fractured dolomite. The study was focused on the recognition of the structure and properties of the dolomite layer lying directly within the roof of excavations. The first tests were performed with seismic tomography for the recognition of anomalous changes in the elastic properties of the rock mass. The results of these studies were used to design a control borehole for a detailed geological engineering assessment and BGPR surveys with 100MHz antennas. Seismic tomography enabled the identification of changes in Pwave and S-wave velocity, the Vp/Vs ratio, dynamic Poisson's ratio and dynamic Young's modulus. It was clear that seismic anomalies required verification by other methods. The BGPR survey was performed in a specially designed borehole, passing through the selected seismic anomalies. While the borehole was being drilled, the outflow of gases was identified, with varying amounts of CH4, CO2, and H2S detected, as well as water outflow. The results of BGPR confirmed the location of a reservoir of water and gases, about 30 m in length, found in layer of dolomite. The direct cause of the BGPR anomaly was assumed to be intensive fracturing, a greater content of clay material in the dolomite, and the presence of water in the fractured zone. The BGPR image was correlated with information on lithology, fracturing based on the RQD index and additional information acquired during drilling about water and gases surveys and other symptoms. The achieved results also showed a very strong correlation between the location of the zone containing gases and water and the anomalous S-wave velocity and field of dynamic Poisson?s ratio, and to a lesser extent other seismic parameters. It was found that the other measured seismic anomalies may be of the same nature as those identified in the control borehole and accordingly will require the implementation of detailed identification. The performed tests have also shown the usefulness of geophysical methods to identify geodynamic hazards under the geological and mining conditions of the copper ore deposit in the Rudna mine.

Aug 1, 2013

By Chandrakala Kari, Divyang Shah, Lakshmi Kanth Reddy, Kaushik Vakil, Sanjay Sarkar, Bhavin Desai

Gases rich in sulfur dioxide generated as a by-product of smelting and converting operations of copper concentrate contain selenium apart from zinc, lead, copper, cadmium, bismuth, antimony, and arsenic. The gaseous stream is heat exchanged in waste heat boiler, dust collected in electrostatic precipitator followed by cleaning in reverse jet scrubber to remove fumes, halogens and fine dust before passing to DCDA Monsanto catalytic converter to produce commercial grade sulfuric acid. The gas cleaning section of the acid plant uses water to scrub the smelting gases. During scrubbing, precipitated solids, known as sludge, settles at the bottom of the reverse jet scrubber containing 30 to 40 wt% copper and selenium up to 40 wt% selenium. In the existing process, the sludge collected during scrubber cleaning process is directly recycled to the smelter for copper recovery. However, the selenium is expected to again vaporize due to high oxidation potential during smelting and converting, causing accumulation of selenium in sludge. In present investigation, a roasting process has been developed to recover the selenium from acid plant sludge before charging it to smelter for copper recovery. Selenium is associated with copper in acid plant sludge as copper selenide, as determined by X-ray diffraction and electron microscopy. Thermodynamic and thermo-gravimetry study revealed that the copper selenide phase present in the sludge was amenable to oxidation at 600°C forming oxides of copper and selenium (Cu-Se-O). However, the dissociation of selenium from the copper oxide was made possible by sulfatation using sulfur dioxide between 450°C to 600°C, resulting into the formation of CuSO4(s) and SeO2(g). Lab scale experiments were carried out in vertical tubular furnace to determine the optimum roasting conditions with respect to roasting time, temperature and molar ratio of O2:SO2. Using these optimum conditions, selenium up to 90 wt. % in the form of SeO2 vapors could be recovered from the acid plant sludge in a large scale commercial roaster. Roasted sludge free from selenium and containing oxides and sulfates of copper could now be recycled in the smelter for copper recovery. INTRODUCTION There is an increasing demand for minor metals due to their use in innovative technologies. Similarly, the increase in demand for selenium is expected due to disruption in sectors related to renewable energy and photovoltaic battery. Selenium is a chalcogen and a non-metal with black or red crystalline appearance. Selenium is used in the glass industry to decolorize glass and to make red-colored glasses and enamels. It is also used in solar cells and as a photographic toner. Selenium is used as a brasses in stainless steel to improve its machinability. Selenium sulfide is used in anti-dandruff shampoos. In spite of the toxicity of its compounds, selenium is also an essential trace element for humans and animals. Selenium occasionally occurs free in nature, but more often occurs as selenides of iron, lead, silver and copper. There is an urgent need for the development of new methods for selenium recovery from the existing resources. Commercially, selenium is obtained only from anode mud produced during electrolytic refinery of copper.

Jan 1, 2019

By J. P. Sims

Abstract - Ultramafic to mafic igneous intrusions of the Las Aguilas district form part of a belt of generally mafic plutonic bodies within medium- and high-grade early Paleozoic metamorphic rocks in the southern Sierras Pampeanas region, Province of San Luis. The intrusions host the largest known nickel sulfide resource in Argentina and contain significant Cu, Co and PGE mineralization (2.2 Mt at 0.5% Ni, 0.5% Cu, 0.035% Co). Sulfides at Las Aguilas Este, one of two principal mineralized zones, are hosted by a body comprising subvertically dipping units of predominantly orthopyroxenite and melanorite cumulate, with lesser dunite, harzburgite, norite, leuconorite, and amphibolite. The units are zoned horizontally from ultramafic to mafic compositions, representing primary magmatic zonation away from an original base or side of the intrusion. Intercumulus nettextured and disseminated aggregates of pyrrhotite-chalcopyrite-pentlandite are concentrated in the peridotitic zones and extend into melanorite. Whole rock major and trace element compositions, and olivine chemistry, indicate that the parent magma was gabbroic/basaltic with 100 (Mg/Mg+Fe) near 59, and resembles tholeiitic magmas generated in subduction-related arc, or back-arc settings. Unusually aluminous Cr-bearing spinel is compositionally similar to those in some synorogenic mafic/ultramafic plutons in magmatic arc settings. Relatively Ni-depleted olivines and low Cu/Pd ratios are indicative of magmatic sulfide segregation early in the crystallization of the magma. Early orthopyroxene saturation and virtual lack of clinopyroxene, in conjunction with sulfur isotope values up to +6.6 ‰, spinel compositions, and presence of graphite, phlogopite and magmatic hornblende, all attest to probable crustal contamination of the parent magma. Assimilation of crustal sulfur may have been crucial in the early attainment of sulfide saturation and resultant formation of magmatic Ni-Cu sulfide mineralization. Fabrics, textures and mineralogy of the intrusions and country rocks and U-Pb zircon dating indicate syntectonic-synmetamorphic emplacement at 478±6 Ma during the Famatinian (Ordovician) orogeny. Minor to locally significant recrystallization and deformation of mafic-ultramafic rocks and redistribution of sulfides and PGE occurred during and following the Famatinian orogeny. The Las Aguilas intrusion is one of several tholeiitic mafic-ultramafic intrusive complexes within an Ordovician arc - back-arc system in the Sierras Pampeanas. Aeromagnetic datasets and regional mapping suggest there is further potential for intrusion-hosted Ni-Cu mineralization along this eroded magmatic arc.

Jan 1, 1999

By Brooke Clements

The Buffalo Head Hills region is located approximately 350 kilometres northwest of the city of Edmonton in northcentral Alberta (Figure 1). The Alberta diamond joint venture consisting of Ashton Mining of Canada Inc., Alberta Energy Company Ltd and Pure Gold Minerals Inc. began exploring for kimberlites in the Buffalo Head Hills region in late 1996. At the time, the Mountain Lake diatreme, located 200 kilometres to the southwest, was the only reported kimberlitic rock in Alberta (Leckie et al., 1997, Figure 1). Exploration efforts since 1996 have successfully identified a new diamondiferous kimberlite province in Canada.

May 1, 2001

By Alvaro Diaz

Introduction, who is Teck Red Dog and Quebrada Blanca Mines Uniqueness of environment Arctic versus High Altitude Conditions Logistical challenges People and Stakeholders Conclusions

May 1, 2013

By Michael S. Moats, Shijie Wang, Timothy Robinson

In 1987, John Schloen published a survey and analysis of copper electrorefining tank room data. Following this paper, a series of copper electrorefining surveys have been conducted and presented at each of the Copper-Cobre meetings over the past 20+ years (1991, 1995, 1999, 2003, 2007, 2010 and 2013). For each of these surveys, William Davenport has been key driving force in the collection and analysis of data. To honour Professor Davenport’s contribution to copper processing, a review of the data was conducted. Historic trends and possible future technologies are discussed.

Jan 1, 2014

By BARRY BANNATYNE

Non-swelling bentonite has been quarried in Manitoba by Pembina Mountain Clays Limited since 1941. It occurs in several thin layers near the base of the Pembina Member of the Upper Cretaceous Vermilion River Formation, and is quarried from the narrow outcrop belt along the slope of the Manitoba Escarpment. It is marketed both as natural and activated bentonite for a variety of specialized uses. Percolation of acidic water through bentonite has produced a naturally activated bentonite with good absorbent properties; these properties are enhanced by treatment with sulphuric acid to produce an activated bentonitefor decolourizing petroleum and vegetable oil.

Jan 1, 1984

By G. H. K. Pearse

Sulphur is derived from both 'voluntary' and 'involuntary' production. The former category includes sulphur obtained from elemental sulphur deposits and from pyrite and gypsumanhydrite deposits. Sulphur in the latter category is produced by pollution abatement at fossil Juel plants and from treatment of metallic sulphides. Canada is the world's largest sulphur exporter and third largest producer. Main resources of Canadian sulphur are sulphurous fossil fuels, metallic sulphides and native sulphur. Only the first two sources have produced sulphur in Canada 10 date; the first source accounts for over 85% of total Canadian production. Future sulphur sources will be derived increasingly through pollution abatement and decreasingly through voluntary production.

Jan 1, 1984

By F. E. Lee

The following outline gives a brief account of some of the ways in which microscopy is applied to the problems arising from the various operations of the Tadanac reduction works, at Trail, B. C. The Sullivan ore is a very fine-grained mixture of galena, marmatite, pyrite and pyrrhotite. The separation of minerals associated so intimately is a difficult task and requires careful control. Various oils and reagents are used in the process as developed, and it is essential that the operators have a means of control which shall be rapid, and at the same time, approximately correct. This result is obtained by microscopic analysis in the following manner: The operator places a quantity of the material upon a slide, a drop of water is added, and it is covered with a cover glass. Upon examination with transmitted light, the zinc mineral particles appear reddish, the ordinary gangue colorless, the lead and iron sulphides opaque. This method has proved of great assistance both in the development and in the operation of the present method for concentrating Sullivan ore. The miscroscope has thus become as much a part of the metallurgical equipment as the balance and burette. The microscope used in the laboratory is a Fuess "petrographic" with a specially-made vertical "illuminator" by Bausch & Lomb, with the usual accessories.

Jan 1, 1924

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

By John S. Stevenson

The Twin ''J' mine is on mount Sicker; 8 miles by road northwest from Duncan; on Vancouver island. It includes the old Lenora; Tyee; and Richard III mines; formerly under separate ownership but now under the single ownership of Twin "J' Mines; Limited.

Jan 1, 1954

By W. H. Hastings

Introductory In the amount of her coal reserves, Saskatchewan ranks third among the provinces of the Dominion, with a total, as estimated by D. B. Dowling, of 59,812,000,000 tons. All the coal so far discovered in the Province is lignite, and it would appear unlikely that bituminous or higher grade coals exist. General Occurrence of the Coal The location of the coal-bearing formations in Saskatchewan is shown on the accompanying map. It will be seen that the areas lie principally in the southern part of the Province. The more darkly shaded areas indicate locations where development is taking place, or where coal-seams are known to occur, either through outcrops in valley-sides or through having been encountered during boring operations. The coal-seams are not necessarily continuous throughout the shaded areas, but in all pans of these there are coal possibilities. It is quite possible that small outliers of the coal-bearing formations may occur further north in the Province, but, generally speaking, coal is not likely to be found outside the shaded areas.

Jan 1, 1929

By H. W. Little

INTRODUCTION MINERAL deposits of Salmo map-area (Figure 1) have aroused the interest of prospectors for more than a half-century. Properties within the map-area have produced lead, zinc, silver, tungsten, and gold. Sheep Creek mining camp ranks fifth in the Province in the total production of gold, but during recent years interest has been concentrated upon base metals, and meticulous prospecting and exploration have resulted in the discovery of many large zinc-lead orebodies. PREVIOUS WORK Geological investigations of the region were begun long ago, and it is interesting to trace the development of ideas with our increasing knowledge of the geology of this complex area. The first geological examination of the rocks of Salmo map-area was made in 1859-60 by H. Bauerman (1), who was employed as geologist accompanying the first international Boundary Survey. Bauerman examined the rocks exposed along Pend d'Oreille river and published a section indicating that the sedimentary rocks are probably of Palaeozoic age, and are intruded by granite of unknown age. McConnell and Brock(2), in 1894 - 1900, carried out the reconnaissance mapping of the West Kootenay Sheet, on which they outlined the Mesozoic rocks of the Rossland Beaver Mountain volcanic groups that they believed rested unconformably upon the sedimentary rocks to the southeast, which they regarded as of Palaeozoic age.

Jan 1, 1951

By Alexander Smith

Surf Point and Edye Pass mines are on the northwestern part of Porcher island; 25 miles southwest of Prince Rupert. During the 1930's they produced about $750; 000 in gold from ore averaging better than one-half ounce a ton. The deposits are quartz veins; containing auriferous pyrite; concentrates average about 8 oz. gold a ton. The veins occur in a quartz diorite; stock. Their distribution shows an apparent control by primary flow structures; for the principal deposits lie on the axis of an arch of flow layers. The technique used in mapping the structures in the intrusive is that known as the Cloos method and described by Balk.

Jan 1, 1954

By Mustafa Kumral

Monte ? Carlo simulation is often used to assess the risks associated with uncertain variables in mining operations. The success of Monte-Carlo simulations depends upon reproducing the dependencies among variables to some extent. However, some variables may exhibit different dependency patterns. In these cases, classical techniques for dependency quantification cannot capture dependencies. As an alternative, the copulas allow modeling nonlinear dependencies. Furthermore, any choice of marginal distributions can be used. Especially, for the data, which is sensitive to extreme case such as financial crisis, the copulas arise as a means to reproduce the correlations among variables. In this paper, the copulas are introduced to mining practitioners using Monte-Carlo simulations for risk assessment. Then, a case study is given to show the superiority of the copulas over classical techniques using ModelRisk Software. In conclusion, it was observed that the copulas enhance the quality of Monte-Carlo simulations by capturing variable dependencies.

Aug 1, 2013

By H. E. Lake

VERY EARLY in the initial stages of underground development work at Eldorado's Beaverlodge operation, the decision was made to use mill tailings as a backfill product. Mining and milling commenced in June, 1953, using locally available sand as backfill, while test work and installation of a plant was carried out to prepare ?and deliver the tailings to the mining areas. The first use of tailings was made in February, 1954, a sandslime separation being carried out with hydraulic cyclones. To date (January. 1956), approximately l 40,000 tons of fill have been used in the stoping areas, providing very effective support in a 50 deg. Vein system of cut-and-fill mining. The recoverable portion of the mill tailings amounts to 40 to 45 per cent, which has resulted in a product giving a percolation rate of 6 to 10 inches per hour. Owing to the fact that Eldorado has milled from 15 to 2 5 per cent more ore than it has mined, through the purchase of custom ore, the degree of control on the sand-slime separation has not been as critical as it might normally be when the filling operation must depend only on the tailings from ore mined. A description of the conditions involved and of the plant as finally installed is given below. It might be mentioned here that, with the impending increase in milling capacity from 700 tons to 2,000 tons p.er day, the present plant will be considerably altered within the ensuing year to handle the increased tonnage and distribution.

Jan 1, 1956

By I. Kylmakorpi

In non-ferrous metal smelting, when the concentrate entering the furnace contains high levels of moisture, energy requirement for heating and drying increases and large volumes of exhaust are produced. To solve this problem, rotary dryers and flash dryers using direct heating, and also steam dryers using indirect heating have all been used for drying concentrate. The focus of this paper is to present the development and current applications of the Kumera Rotary steam dryer. The advantages of this technology are numerous, including reduced heating requirements, environmental friendliness, operation reliability and minimum maintenance needs; making it a top choice for drying concentrate.

Jan 1, 2008

By STEPHEN V. FORGERON

The Loch Lamond celestite properties in central Cape Breton Island were mined by Kaiser Celestite Mining Limited from 1970 until 1976. Poor market conditions in J976forced operations to cease. Kaiser holdings included the Lake Enon, MacRae and A mac prospects. A total of about 272,000 tonnes of raw celestite have been mined. Celestite deposits are situated in the Loch Lamond Basin, specifically in Lower Windsor sedimentary rocks. Of the five formations in the Lower Windsor Group, celestite is found in the upper four. Celestite in the Enon Formation occasionally replaces shale that separates stromatolitic dolomite columns; elsewhere in the formation it occurs in association with siltstone and gypsum. Jn the B2 Limestone Formation celestite fills pores or grades between limestone and gypsum. It replaces both limestone and silty limestone conglomerate in the Loch Lamond Formation; this limestone is of unusually high grade (60 to 70% SrSO,J for the area. Evidence indicates that the Uist Formation may hold important celestite reserves. Original celestite mineralization probably resulted from evaporation of seawater on mudflats or 'sabkhas'. Secondary mineralization also may have occurred. Strontium ions could have been leached from pre-existing concentrations and overlying gypsum, moved downdip in groundwater and combined with sulphate rich waters to deposit as celestite in porous B2 limestones.

Jan 1, 1984

By M. Jahazi, J. Gholipour

Design and manufacturing of parts using hydroforming process require knowledge about material behaviour and tribological effects during hydroforming. Lubrication is one of the key issues in successfully hydroform the tubes. A Ni-based super alloy tube with 50.8 mm (2 inches) outer diameter and 0.9 mm (0.035 inches) thickness is considered for this research to study the effect of lubricants on the formability of the tubes. Hydroforming of a hollow compressor blade is considered for this project. A combination of press forming and hydroforming is employed to produce the part. LS-DYNA, an explicit dynamic finite element code, is used to model the experiments. Different lubricants are modeled using different coefficient of friction in the model. Predicted results for strain distribution at a critical section of the tube are extracted for each case to evaluate the effect of different lubricants on the process.

Jan 1, 2006