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By M. R. Campbell

"IntroductionON THE LAST DAY of December, 1951, a half-century of steel production was completed in the open hearth department of Dominion Iron & Steel, Limited, in Sydney, Nova Scotia.During that period, almost every known variation of basic steel making practice was used in working out a steel making process which would overcome the difficult metallurgical problems imposed by the use of Cape Breton coal and Wabana ore.This paper is presented as a brief review of these steel making practices, setting forth the fundamental metallurgical factors involved in their success or failure.Establishing the IndustryThe story of steel production at Sydney is closely interwoven with that of coal. The steel industry owes its inception to a desire on the part of the Dominion Coal Company, which was incorporated in 1893, to improve its marketing position by increasing sales of slack coal and providing a year-round demand for its product. Accordingly, the Dominion Iron and Steel Company, Limited, was incorporated on March 30th, 1899, with Mr. H. M. Whitney -who was President of the Dominion Coal Company -as its first President. The new Company was given powers to manufacture and process iron and steel, and to mine all minerals, including coal.A strong inducement to the industry was the bounty offered by the Dominion Government for the production of both iron and steel."

Jan 1, 1952

By R. B. Nourse, S. F. Gwynn-Jones, S. Nikolic, M. L. Bakker, I. McDougall, H. Joubert

"Tenova Pyromet’s core furnace knowhow and expertise has been built within the ferroalloy and nickel/platinum group metal (PGM) industries with the supply of electric furnaces for a number of nickel/PGM operators, including Eastplats, Lonmin, and Anglo-Platinum in South Africa, Mineraçào Serra Da Fortaleza in Brazil, and Norilsk Nickel in Russia. Tenova Pyromet has also supplied the electrode columns and associated electrode equipment – the heart of the electric furnace technology – for cobalt recovery in furnaces in Zambia and the Democratic Republic of the Congo. The quantity and size of projects undertaken by Tenova Pyromet has provided the opportunity to continuously improve furnace designs and the scope of supply, culminating in the most recent nickel/PGM project currently under construction at Northam Platinum. Through this innovative culture, the Tenova Pyromet Base Metals Initiative was formed in 2015 to develop the Novasmelt™ Furnace; a next generation optimised Top Submerged Lance (TSL) furnace design. The combination of Tenova Pyromet’s advanced Novasmelt™ product with our industry leading electric furnace technology are discussed with reference to applications for nickel and cobalt production. Flowsheet arrangements are compared summarising potential capital savings, operating requirements and achievement of downstream product quality.INTRODUCTION Tenova Pyromet is a leading player in the field of smelting technology development and equipment supply. Tenova Pyromet is the result of the union of three furnace suppliers under the Tenova banner: Techint Technologies (Tagliaferri), Core Furnace Systems Corp (Lectromelt) and Pyromet Technologies. The furnace experience of the combined groups dates back over a century with the earliest Lectromelt going into production in the early 1900s. Throughout the modern era, Tenova Pyromet has developed a reputation for providing dependable innovative smelting technology, high quality equipment and sound project execution to a worldwide client base with customer plants operating in Europe, Southern Africa, North America, South America, Russia, Kazakhstan, the Middle East, South Korea, and India. Tenova Pyromet’s core knowledge and expertise was developed in the South African ferroalloy, base metals, and platinum group metals (PGM) smelting industries. Tenova Pyromet has spent considerable effort on development and has contributed significantly to improve the state of the smelting industry. Tenova Pyromet’s electrode columns have become widely renowned and are now providing significant benefits, especially in increased furnace availability, to many smelting furnace operators. The electrode column is the heart of the furnace as it delivers a controlled amount of electrical energy, at an optimum depth in the burden/bath, to the smelting process. Every furnace is custom designed to the specific operating range and optimal operating point of that furnace and process"

Jan 1, 2017

By N. S. Spence

INTRODUCTION WHILE TITANIUM, the element, has been known for over 150 years, titanium, the metal, is a relative newcomer to the metallurgical and industrial scene. The reasons for this chiefly lie in the refract1Hy nature of titanium compounds; the high melting point of the metal; the great activity of elemental titanium, particularly at temperatures close to .and above the melting point; and the pronounced deleterious influence of certain impurities on its mechanical proper-ties. Early efforts at production of the metal were, consequently, either unsuccessful or resulted in products having sub-metallic properties. With the considerable improvement in equipment, materials, and skills that have developed within the past twenty-five years, later investigators have had a better opportunity to overcome some of the inherent practical obstacles and to come to grips with the essential technical problems. NATURAL ABUNDANCE OF TITANIUM Titanium is one of the most abundant metallic elements. It has been estimated (1) that titanium comp-rises about 0.65 per cent of the earth's crust, and therefore ranks fourth among the structurally useful metals in the order: aluminum, iron, magnesium, titanium. It must be appreciated that the relative abundance of the element is only a crude indication of its potential availability, since a very substantial proportion is present as a minor constituent in practically all igneous rocks. By comparison, present-day ores of titanium are relatively few and are but a minor fraction of the estimated total titanium contained in the earth' s crust.

Jan 1, 1951

By Kousuke Takahata, Hirofumi Yoshimura, Jun Nakahigashi

Studies of a protium treatment for grain refinement of a + ß type titanium alloy are reviewed and recent experimental results are introduced. Protium treatment consists of the following three processes: (1) protium absorption, (2) martensitic transformation and hot working, and (3) final treatment for protium desorption and recrystallization. A combination of these processes results in the ultra-fine grains of 0.3 to 0.5 µm in diameter with high angle boundaries. The ultra-fine-grained material exhibits superplastic elongation of over 9000%. Superplastic forming was successfully used to fabricate a denture base. These materials may be widely applicable as biomaterials in various medical industries.

Jan 1, 2004

By S. R. Noble, F. R. Harris, E. T. C. Spooner

"The Logtung deposit discovered in 1976, is an example of large tonnage (162 million tonnes), low grade (0.13% WO3 and 0.052% MoS;) W(scheelite)-Mo mineralization related to multiple felsic intrusions. Because mineralization is predominantly fracture-controlled (> 95 %) rather than disseminated, Log tung is not a skarn deposit. Metamorphism of the Logtung country rocks (interbedded calcareous shale and graphitic quartizite) to a series of competent reaction skarns (quartz-diopside-garnet calc-silicate, biotite quartzite and wollastonite-vesuvianite calc-silicate) clearly precedes W-Mo mineralization. Hence mineralization was related to permeability created by hydraulic fracturing and not replacement processes.Logtung shows a theme of several phases of mineralization (4) related to multiple intrusions (>2) which is similar to that of the Climax and Urad-Henderson Mo systems. The earliest quartzmolybdoscheelite vein system, which consists of a typical ""porphyrystyle"" crackle-breccia of thin (0.5 mm to 4 mm) quartz-garnetdiopside- molybdoscheelite veins, is related to a high Si02 (approx. 76%), seriate-porphyritic monzogranite stock (approx. 2 km by 0.5 to 1 km) of Cretaceous age (118 ±2 Ma [2u]; Stewart, 1983). Later quartz-pyrite scheelite (fluorite-KINa-feldspars-molybdenite) veins, with prominent green, hornblende-bearing alteration selvages, and quartz-molybdenite (-pyrite-jluorite-scheelite) veins are related to a quartz-feldspar-spessartine-rich garnet porphyritic felsic dike complex approximately 500 m across. Both intrusive phases have anomalously high Wand Mo concentrations of about 100 ppm and 50 ppm respectively, which Stewart (1983) attributes to a primary enrichment. The final stage of mineralization consists of a prominent 4.5 km by 1 km zone of 1 em to 1 m wide polymetallic sheeted veins centred on the felsic dike complex. The system is zoned from quartz scheelite-molybdenite-pyrite-blue-green beryl-jluoritebismuthinite veins in the core to Pb-Zn-Ag veins with abundant arsenopyrite and minor Sn (approx. 0.1%) in the northeast. The focus of recurrent intrusive and hydrothermal activity was located above a flank or nose of the monzogranite stock.The distribution of WO3 and MoS2 grades within the approximately 750 m (across) by 300m (evaluation depth) mineralized zone is a result of the variable superimposition of the four separate vein systems each with different W:Mo ratios. Well-defined Wand Mo ore, shells such as those at Climax, Henderson and Mt. Emmons did not develop at Logtung. The upper surface of the mineralized zone, as shown by the 0.03% MoS2 contour defines an elongate dome with an apical region approximately coincident with the felsic dike complex. Hydrothermal alteration occurs as well-defined vein selvages, and not as pervasive zones.The Logtung deposit shows many similarities to porphyry Mo deposits in the western Cordillera and may be identified as a porphyry W(scheelite)-Mo deposit, with a W:·Mo ratio of 3.3:1. The principal reasons are: (1) mineralization is spatially associated with porphyritic granitic intrusions and (2) much of the scheelite and molybdenite occurs in typical ""porphyry-style"" vein stockworks"

Jan 1, 1995

By Gordon Jackson

"There are two accomplishments of air and gas drilling: a new series of economic and mechanical challenges; and, acceptance as a standard drilling and completion tool.The new challenges are related to the concept of using a gaseous circulating medium in drilling for oil or gas. For purposes of discussion, a two part division has been made: the challenge of fluid invasion control and that of equipment and tools. Great strides have been made in the development of materials and techniques to combat formation fluid invasion. Chemicals and the ""mist drilling"" technique, now in use, have the versatility to cope with a wide range of downhole fluid entry conditions.Equipment and tools have been developed to meet the challenges of better, more economic drilling and completion possible with a gaseous circulating fluid. Economic and operational challenges remain.Acceptance of air and gas drilling as a normal operating tool was reached with difficulty. It is now established as a means of reducing costs in exploratory and develop-mental well drilling, exemplified in a recent study of 226 wells covering 419,407 feet of hole in the United States. Air reached the projected depth in 85 per cent of the operations, although formation water was encountered in 48.7 per cent of the holes. Slim hole bit performance and cost all compared for overall bit averages as part of analysis."

Jan 1, 1961

By Y. J. Yu, C. D. Zhang, Y. S. Zhao, W. G. Liang, Y. D. Geng, J. L. Bi

"In this study, the coefficient of thermal expansion (CTE) and thermal conductivity (TC) of shale in two perpendicular directions, vertical and parallel to the bedding of the rock, are firstly measured by experiment. The experimental results show that the CTE of the shale in the vertical direction is 1.69 times as much as that in the parallel direction, while the TC in the parallel direction is 1.83 times larger than that of the vertical direction. Based on the no initial strain assumptions, numerical simulations for the thermal cracking in shale are carried out with the obtained coefficients. Using finite element method and thermal-mechanical coupling theory, two fracture mechanical parameters, KI and J-integral of the shale are also analyzed for the shale thermal fracturing. The simulation results show that both KI and J-integral reach the maximum when the fracturing angle equals to 0° in the shale, namely parallel to the bedding direciton. It is also found that the two fracture parameters decrease with the fracturing angle increasing. Additionally, the thermal fracturing effect of the shale is evaluated under a given scenario. The study is significant for shale oil or gas recovery by in situ pyrolyzing method.INTRODUCTIONOil shale is regarded as a kind of unconventional resource that can contribute to production of shale oil and hydrocarbon gases (Rahm & Dianne, 2011). As is known that there is a large deposit of oil shale in China, and present technology for exploiting oil shale still concentrates on open-pit mining, obtaining shale oil by retorting shale on the ground (Li, Tang, Xue, Zheng, & Du, 2014; Qian, Yin, 2008). However, this technology has a bad effect on the environment and leads to severe resource waste for utilizing oil shale. Exploiting oil shale by in-situ method for ‘green mining’ is widely necessary in China (Kang, Wang, Cao, Liang, Chang, & Liu, 2013; Waters, Dean, Downie, Kerrihard, Austbo, & McPherson, 2009; Zoback, Kohli, Das, & McClure, 2012). One of effective method to exploit shale oil is heating oil shale in-situ underground. For instance, the in-situ conversion process (ICP technique) from Shell Company etc. used a direct heating method, and convectional heating oil shale underground by injecting superheated steam from Mining Technology Institute, Taiyuan University of Technology and constructing horizontal fracture in vertical wellbore from Chevron Company use indirect heating method (Chaudhary, Ehlig, & Wattenbarger, 2011; Hazra, Lee, Economides, & Moridis, 2013; Zhao et al., 2010). The convectional heating method contains complicated procedures with phase transition in double-media of fracture-matrix of oil shale subjected to multi-physical fields coupling including stress, fluid and temperature (Zhao et al., 2010). The characteristics of thermodynamics, solid mechanics and seepage of oil shale have been investigated separately (Hopkins, Rosen, & Hill,1998; Kang, Zhao, & Yang, 2008; Yang, Zhao, Kang, 2010; Zhao, Yang, Feng, Liang, & Kang, 2008; Zhao, Cao, Zhao, Lin, & Wang, 2008). However, it is quite difficult to solve constrained problem of each physical parameter in multi-physical fields coupling for oil shale pyrolysis."

Jan 1, 2015

By Owen Matthews

Introduction For the past year and a half, the mill of Cochenour Willans Gold Mines, Limited, McKenzie Island, Ontario has been roasting arsenopyrite-gold concentrates, prior to cyanidation, by means of a roaster employing techniques that are new and novel. The roaster is known as the Dorrco 'fluo-solids reactor', and the technique as 'fluidization'. The reactor has demonstrated its ability to roast a flotation concentrate containing arsenopyrite, pyrite, stibnite, small quantities of other sulphides, and some lime silicates and carbonates, yielding a calcine consisting mainly of porous iron oxide, plus the gold values. This calcine is readily amenable to cyanidation. Bulk shipments of concentrates to a distant custom smelter, as practised prior to this installation, has thus been eliminated, with appreciable savings in smelting charges, freight costs, and interest losses during shipment and smelting. This is the pioneer installation of fluo-solids roasting at a Canadian mill and up to the present performance results have not been published. It is the purpose of this paper to present the information now available for the benefit of other millmen who may be confronted with identical or similar problems to those encountered and solved at Cochenour Willans.

Jan 1, 1949

By Stefan Boshkov

THE ADVENT of mining at great depth has brought to the fore the question of stresses around mine openings. The many-pronged attack on this problem is certified by the accelerated appearance, in the mining literature, of articles on various topics related to this subject (1). Whereas it may be agreed that we, of the mining profession, have fallen woefully behind in research and the development of an understanding of this important facet of the general problem of mining, it must also be accepted that the analysis of the stresses in a mine structure is usually more complex than is the case in the majority of structures encountered and dealt with in civil engineering. Whereas homogeneity and isotropy are readily acceptable for most metals, such properties are but crudely approximated in rocks. Whereas the external loads on a structure in civil engineering may be readily determined, those on a mining structure are subject to ?conjecture. Whereas the limits of the structure may readily be defined in civil engineering, the boundaries of the mining structure are, in most cases, indeterminate, and subject to intelligent guesswork, at best.

Jan 1, 1956

By L. M. Pidgeon

"Part I. - PrinciplesIntroductionIf the oxides of the metals are listed in decreasing order of the magnitude of their heats of formation, the list appearing in Table 1 will be formed. It will be apparent at once that this is essentially the well-known electrochemical series (Table li). The metals at the bottom of the list exhibit great stability and are attacked only by the most violent of chemical reagents. Higher on the list, the metals become more reactive until, at the head of the list, the metals lithium and calcium are unstable in moist air.The reactive metals to be considered lie above manganese. In this group will be found familiar and abundant metals such as aluminium and magnesium, the unfamiliar yet abundant metal titanium, the rare and mysterious metal beryllium, and others of greater or less interest.While these metals exhibit properties as unlike as those of uranium and magnesium, they have in common a specialized and difficult extractive metallurgy. They form compounds of great stability, and their reduction is to varying degrees difficult. The position of a metal in Table 1 (and more particu1arly its position in the free energy column) gives a numerical value to this property.Oxides with low free energies of formation may be reduced with great ease; thus silver and mercury may be produced from their oxides by simple heating in air.Lead, iron, and zinc may be separated from their oxides by heating with carbon to moderate temperatures. Magnesium oxide, on the other hand, .requires a high temperature and very special conditions before it will yield magnesium metal."

Jan 1, 1950

By A. Panteleyev, C. S. Ney, R. J. Cathro, A. Sutherland Brown

The general distribution of metal deposits in the Canadian Cordillera can be related to its tectonic evolution. The Canadian Cordillera is naturally divisible into five longitudinal tectonic belts within which rocks are broadly similar in type, age and history. From west to east they are the Insular, Coast Crystalline, Intermontane, Omineca and Eastern Marginal belts. Seven classes of metal deposits in the Canadian Cordillera are defined and their characteristics described. These classes are skarn, porphyry, massive sulphide, stratiform, magmatic, copper in basic lavas, and vein deposits. Maps showing the distribution of medal and metal-group concentrations serve to illustrate the relations in space and time between mineralization and geologic evolution.

Jan 1, 1971

By A. E. Boone

"The paper presents critical areas in which improved coordination of effort by industry, government and sup-pliers will be essential to continue the growth record of the Canadian mining industry into the 'seventies'. The analysis includes: exploration, production, mining methods, research and development, markets, management and industrial relations. Performance objectives are suggested where tangible results can be measured. The author suggests the methods by which the 'seventies' can be the greatest decade in the history of Canadian mining. It is indicated that a national mineral policy is essential to the Canadian mineral industry."

Jan 1, 1970

By I. H. Warren, Forward F. A

The reduction of aqueous slurries of uranyl carbonate at elevated temperature with compressed hydrogen m the presence of metal catalysts and certain organic promoters has been shown. to yield uranium dioxide. The reduction takes place in a sequence of steps. The purity and sintering properties of the dioxide make it of interest as a starting material for fuel element production. Simple control can be exercised over the surface area and oxygen/uranium ratio of the product during reduction. URANIUM dioxide for fueling atomic power reactors 1s conventionally produced as a powder by simultaneously decomposing and reducing ammonium diuranate with hydrogen in a furnace at high temperature. Fuel elements are then generally made from this powder by compacting and sintering ( 1). In order that elements approaching theoretical density may be obtained,

Jan 1, 1961

By J. W. Meier, J. O. Edwards, R. C. Bell

"IntroductionTHE DIE CASTING industry .as we know it today is the direct result of the invention and development of die casting machines during the nineteenth century and of reliable alloys in the twentieth. The early machines were designed to cast low melting point metals such as lead .and tin, and their alloys.It was inevitable that, as these die castings were put into service, the demand should arise for stronger materials. Zinc alloys, often containing lead, tin, copper, and aluminum as major constituents, were relatively easy to cast and stronger than the lead and tin alloys. However, it became apparent after a number of years that these zinc alloys tended to become brittle, distort, and corrode, particularly if kept in warm, humid atmospheres. Thus, considerable quantities of zinc-base .alloys were in use before the trouble was realized and effective measures could .be taken to determine the cause of the instability.The deleterious effect of certain metallic impurities on the properties of zinc •die casting .alloys has now been known for about thirty years. Brauer .and Peirce, and, later, other research workers of the New Jersey Zinc Company such as Anderson and Werley, discovered the pronouned effect of lead, cadmium, and tin on the stability of zinc-alloys."

Jan 1, 1952

By C. G. McLachlan

INTRODUCTION The work described in the following paper was under-taken with a view to determining, if possible, the relative importance of some of the phenomena on which flotation seems to depend, in the hope that, if this information could be obtained, it would be of value in dealing with the problem as a whole. At the outset, brief reference will be made to three papers which had a considerable bearing on the course followed in the present investigation. In 1919, Langmuir, in a paper on 'The Mechanism of the Surface Phenomena of Flotation', showed that mono-molecular films of very great stability could be produced on solid surfaces with oleic acid, but that pure paraffin oil, though spreading readily on a dean dry surface, was easily displaced by water.

Jan 1, 1926

By Peter N. Calder, Garston Blackwell

"The history and analysis of a structurally complex open-pit rock slope displacement are described. The failure involved part of the only haulage access to a major ore zone. The ongoing movement was monitored using an electronic distance measuring device and a continuous electronic system specifically designed for the problem. A major fault, infilled with a thick clay gouge, and intersected by other structural features, resulted in the transfer of weight to a rock mass acting as a buttress in the lower regions. Movements were affected by blasting vibrations and ground-water conditions. Remedial measures included limiting blasting levels and lowering the water table, following which mining was successfully resumed in the area.IntroductionBrenda Mines is situated in a mountainous region of the southern interior of British Columbia; the location is indicated on Figure 1 . The elevation is approximately 5000 ft , giving a climate typical of more northern areas. Temperatures vary from -30°C to + 30°C. A snowfall level of 400-800 cm is experienced from November to April. During the spring, a heavy runoff period occurs, increasing the pumping rate in the pit from a nominal 50* gal/min to 2000 gal/min.The orebody occurs in a fractured Jurassic rock mass referred to as the Brenda Stock; it is approximately 3000 ft in diameter and 1000 ft deep. The Brenda Stock was intruded into the Upper Triassic Nicola Group tuffs, breccias and argillites. Mineralization occurred in several stages in a relatively homogeneous quartz diorite host rock. Shearing, faulting and jointing occured later in many stages, producing mineralized clay gouge zones up to several feet in thickness'> , These gouge zones have a major effect on the stability of the pit walls.The structural geology of the pit walls is otherwise relatively simple. Figure 2 is a conventional pole diagram indicating the orientation of the rock structural systems which are present. The major system has an average dip of approximately 70 degrees to the south and strikes approximately east /west , it is not undercu t by the pit slope. Figure 3 is a photograph of part of the North wall on which this system is indicated.The basic pit design consists of a working bench height of 50 ft, with a final wall height of 100 ft between berm s and a 100-ft-wide berm every second lift. Combined with a local face slope of 50-70 degrees, the resulting wall slope, not including haulage roads, is 45 degrees. Figures 4 and 5 are generalized plans and sectional views of the pit."

Jan 1, 1980

By A. Mazhary

"Although sensor-based ore sorting has gained significant attention recently, sorting gold deposits still face a high level of skepticism by gold mining companies. In order to shed some light on the matter, this article looks at two different gold deposits that were examined using X-ray Fluorescence, Electromagnetic and X-ray Transmission sensors. The heterogeneity of each sample is measured based on the assay results of each particle and is related to its sortability. Multivariate linear regression analysis was also performed on the XRF results to find potential proxy elements for detecting gold. The results from these deposits were varied and each sample showed different levels of sortability. While both X-ray sensors proved efficient for different deposits, the electromagnetic sensor failed to produce any promising results. Despite unsatisfactory result for one sample, this technology can have significant advantages in terms of lowering the operational costs and improving head grades and recoveries providing that the deposit is amenable to such separation methods. Therefore, it is important to mention that sensor-based ore sorting is ore and sensor dependent, and as a result, it cannot be applied and be beneficial to all deposits. Therefore, amenability tests are required in order to examine the potential for sensor-based ore sorting before one can reject the idea.INTRODUCTION Although sensor-based ore sorting has gained significant attention recently, sorting gold deposits still face a high level of skepticism by gold mining companies. Except for a few cases presented previously, no new case studies have been published. Previously, mines such as Kloof Gold Mine in South Africa used an optical sorter to sort their waste stockpile in 2003–2004 (Von Ketelhodt, 2009) and then again in 2009 (Von Ketelhodt, Falcon, & Falcon, 2011). More recently, Coeur Operations utilized an XRT sorter for their Kensington Mine in Alaska (Lasley, 2014) and also Anglo-American Platinum used an XRF sorter to pre-concentrate Platinum Group Metals through an algorithm that used chrome, copper and nickel as proxies (Rule, Fouchee, & Swart, 2015)."

Jan 1, 2017

By Olaf Kessler, Jan Kalich, Michael Reich, Julia Osten, Uwe Füssel

Modern automobile bodies consist of different materials, e.g. aluminium alloys and high strength steels. Mechanical joining, e.g. clinching, is very suitable for joining aluminium and steel sheet. But clinching needs a sufficient ductility, which is no longer supplied by high strength steels. Laser-assisted clinching has been shown, to be able to join aluminium and high strength steel sheet successfully. Thereby the steel sheets were heated locally for short times to increase their ductility. Due to the thermal contact between steel and aluminium sheet the aluminium alloys also achieve a local short-time heat treatment. This fact may cause a significant impact, as aluminium sheet in automobile bodies is often used in T4 (or similar) condition and later artificially aged during the paint bake cycle. Aluminium alloys 6016 and 6181 have been short-time heat treated with heating rates up to some 100 K/s. Precipitation and dissolution processes have been monitored in-situ by calorimetry. Mechanical properties have been investigated on as well as after short-time heat treatment by deformation dilatometry. The results show, that suitable short-time annealing parameters during laser-assisted clinching can increase ductility and at the same time act as retrogression for aluminium sheets, resulting in increased strength after aging.

Jan 1, 2015

By R. Stach, S. Gola, P. Zgrzebski, K. Soroko

"At the moment climatic conditions are a primary problem of the exploitation of copper ore. The efficiency of preventive actions in order to improve climatic conditions is connected with the knowledge of changing air in underground excavations. This article demonstrates the analysis of types of ventilation dams which are used in sealing abandoned areas on the maintenance of climatic working conditions in excavations has been conducted at the exploitation in Polish copper ore mines. INTRODUCTION The basis for mining activity performed by KGHM Polska Miedz S.A. is mining copper ores from the deposit lying at depths between 600 and 1,200 m below ground level. Activity has continued since 1963. The copper ore deposit is mined in ‘Lubin’, ‘Rudna’ and ‘Polkowice-Sieroszowice’ mines, where difficult climatic conditions occur. The major factor moulding the climatic conditions in headings is the original temperature of rocks, being the result of geological conditions of the lying of the deposit and the existing geothermal degree. In the faces of present opening-out and preparatory headings, driven from mining areas of ‘Rudna’ and ‘Polkowice-Sieroszowice’ mines in order to open out deeper parts of the deposit, the original temperature of rocks reaches 45°C. Excluding the original temperature of rocks, the following are additional factors affecting the deterioration in the climatic conditions: • thermal properties of deposit rocks, • employed room-and-pillar mining systems, which are characterised by a large surface of exposure of rocks, • using self-propelled mining machines with diesel drive, • a high concentration of mining works, • setting up high-power electrical equipment in headings, • complex structures of mine ventilation networks, • a limited number of ventilating shafts, • constantly longer air-transport routes, • a significant accumulation of water increasing the humidity of supplied air. According to the valid Polish provisions (§21, 2013), the primary criterion of assessment of a climatic hazard is the occurrence at a workstation in an underground mining heading of an equivalent climate temperature of more than 26°C, which temperature is determined according to the following dependence:"

Jan 1, 2019

By R. L. Bruening, N. E. Izatt, S. R. Izatt

The need for selective metal separations has increased as the mining industry encounters more complex ore bodies and demand for higher performance end products expands. The Molecular Recognition Technology (MRT) process uses highly selective SuperLig® resins to remove desired metals from a variety of solutions in the mining and metals processing and recovery industries. MRT separation processes efficiently produce high purity metal products. In this paper, applications of MRT to metal recovery at mg/L to multiple g/L concentration levels are presented and discussed. Specific examples in the precious metal, nickel, cobalt, zinc, copper, and rare earth industries are given.

Jan 1, 2014