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By Y. Wang, S. Liu, K. Jiang

China is the world’s largest producer and consumer of non-ferrous metals. In recent years, significant progress has been made in research and commercial application of pressure leaching technology to produce some nonferrous metals. Research and development activities include a low-pressure, low-temperature leaching technology for complex copper concentrates, a hematite process to treat pressure leach solutions from zinc concentrates, and a pressure leaching - solvent extraction process for molybdenum and rhenium. Examples of commercial practices include a two-stage pressure leach technology in a zinc plant in Danxia, a direct leaching technology in a zinc plant in Zhuzhou, a high pressure acid leaching process for a nickel laterite project in RAMU, and a pressure leaching technology to treat arsenic sulfides in a plant in Guixi. The development of pressure leaching technology for the recovery of lead, vanadium, gallium, germanium, and precious metals in China will also be described in this paper.

Jan 1, 2015

By E. Engelbrecht

"A pressure non-oxidative leach is employed at Anglo American Platinum Base Metal Refiners to extract nickel from a slow cooled matte. The design base requires two 80 m3 autoclaves in parallel to achieve a nickel extraction of 60% at the nameplate capacity of 32.4 ktpa nickel plated. Isothermal modelling of mineralogical and chemical concentration profiles, through a reactive mass balance, permitted rate constant parameter estimation and selection of the most probable reaction pathway. The model was validated with plant data up to a capacity of 26 ktpa Ni plated and suggested by extrapolation that nameplate capacity may be viable through one 80 m3 autoclave.INTRODUCTION Anglo American Platinum Base Metal Refiners is situated on the outskirts of Rustenburg in the North-West province of South-Africa. The refinery produces nickel cathode, copper cathode, cobalt sulphate powder, covellite rich copper pressure leach residue and bulk sodium sulphate through an integrated circuit that refines slow cooled converter matte. The converter matte is milled, non-magnetics are separated as solid nickel copper matte (NCM), and the magnetics are leached yielding a pressure vessel liquor (PVL). The remaining solid platinum group metals (PGM) concentrate after leaching is sent for downstream processing in the Precious Metals Refinery (Hofirek & Kerfoot, 1992). The work presented here is applicable to the base metals refinery which receives the two base metals feed stocks NCM and PVL. In 2009 the capacity of the refinery was upgraded from 21 ktpa nickel cathode plated to 32.4 ktpa. This paper deals with evaluating the capacity of the pressurised non-oxidative nickel leach (NOX) process which accounts for at least 28% of the nickel leached from NCM by design. The NOX design base requires two 80 m3 autoclaves divided into four compartments operated in parallel at 155°C and 600kPa(g). Elevated temperature is required to speed up the leach kinetics of particularly nickel and iron which are trapped in slow leaching mineralogical phases namely millerite and bornite, (Dinham, 2006). The stated equivalent capacity for the NOX configuration was 32.9 ktpa nickel plated at first pass nickel and iron leach efficiencies of 60% and above 80% respectively and is a key step for the selective removal of iron (Bryson, Hofirek, Collins, Stiksma, & Bereaowsky, 2008)."

Jan 1, 2017

By C. O. Swanson

THE purpose of this paper is to discuss the use of the dip needle in the field of mining geology. The subject matter is new only to the extent that it reflects the writer' s added experience in recent years. The treatment is brief, and those interested in a more extended analysis are referred to the articles listed at the end of the paper. In the discovery and tracing of mineral deposits, the clip needle, like most other geophysical instruments, can be used in two ways. One method may be termed direct; the other, indirect. The direct method is that of finding or following certain ore-bodies by virtue of their magnetic properties. Explicitly, or by inference, it is the method which many mining men and practising geophysicists have in mind when they consider whether or not a certain property should be studied by geophysical means. In the ideal case, this method demands little or no knowledge of geological conditions. The indirect method uses the clip needle as an aid to purely geological studies in working out the structure of a mineralized area. Although not as simple as the direct method, it enjoys a much wider field of usefulness. The writer's experience in the past fifteen years, which is believed to be typical, is that the indirect method finds application four or five times as often as the direct method. The indirect method is of particular value because it furnishes information concerning the relationship between geological structure and ore occurrence. Most mining engineers will agree that structural control is an important factor in the localization of ore deposits, and therefore that the subject under consideration is of some interest in mining geology. Specifically, then, the present purpose is to outline the principles and practice of using the clip needle in working? out geological structure.

Jan 1, 1941

By Mehmet F. Tauer, Pierre Trudel

"The metamorphosed mineralized Archean Bourlamaque batholith, dated at 2710 +-54 Ma, is a homogeneous body, composed mainly of quartz diorite; it is cut by late dioritic, mafic and aplitic dykes, and contains metasomatized ultramafic xenoliths. A geochemical investigation confirms the calc-alkaline affinity of the batholith, and the REE profiles are similar (Lal Yb = 3.9 to 8.1) to those of the intermediate to felsic metavolcanic rocks at Val d'Or into which the batholith was intruded and to those of the calc-alkaline members of the Blake River Group at Rouyn.Gold distribution within the batholith is heterogeneous and anomalous. Although the background Au content of the batholith is estimated to be 3.2 ppb Au by RNAA , the estimated median gold content of the batholith is 10 pp b (with P84 =32 and PI 6=3.1 ppb), much higher than that of ""normal"" granites (I to 5 ppb A u). The gold mineralization exhibits a close relationship with shear zones (e.g. Belmoral Mine) or with diorite dykes (e.g. Sullivan, Perron and Courvan mines).The following sequence of geological events is proposed: (I) pretectonic emplacement of the batholith, which is cogenetic with its volcanic host rocks; (2) regional metam orphism and deformation with localized shearing; and (3) hydrothermal alteration and quartz veining. We conclude that: (1) the Bourlamaque batholith is a gold-enriched intrusion, and (2) the determination of average gold content may be an effective method f or distinguishing ""sterile"" intrusions from those with potentials for gold mineralization.RESUMELe batholite archéen minéralise de Bourlamaque, daté de 2710+-54 Ma, est une intrusion homogène, constituée principalement de diorite quartzique, qui a été recoupée par des dykes tardifs de diorite, d'aplite et de composition mafique. Il contient aussi des enclaves de roches ultramafiques metasomatisees. L 'étude géochimique confirme le caractère calco-alcalin du bath olite et les profits des ETR sont semblables (La/ Yb=3.9 a8.1) a ceux des volcanites intermédiaires afe tsiques de la région de Val d'Or dans lesquelles le batholite fait intrusion et à ceux des unites calco-alcalines du Groupe de Blake Ri ver a Rouyn. La distribution de Au dans le batholite est à la fois anomale et hétérogène. Bien que le bruit de fond du batholite ait été estime à 3.2 ppb A u par AANR, sa médiane a été estimée a10 ppb Au (avec P84=32 et PI6= 3.1 ppb) , ce qui est nettement plus élevé que la valeur des roches granitoides ""normales"" donnée dans la littérature (1 a 5 ppb A u). Dans la batholite, la minéralisation aurifère est intimement associée aux zones de cisaillement (e.g. mine Belmoral) au aux dykes de diorite (e.g. mines Sullivan, Perron et Courvan).La séquence des évènements géologiques suivante est proposée: (1) emplacement pre-tectonique du batholite, lequel est cogenetique avec les roches volcaniques encaissantes; (2) deformation et metamorphisme regional avec des cisaillements tectoniques locaux; et (3) altération hydrothermale et développement des veines de quartz. Nous concluons que: (1) le batho lite de Bourlamaque est une intrusion enrichie en Au; (2) la determination de la teneur en Au peu être une méthode efficace pour distinguer les intrusions stériles de celles qui possèderaient un pot entiel pour des minéralisation s aurifères."

Jan 1, 1989

By J G. Brady

This paper discusses the ceramic products used in the construction industry in Canada, as well as the main raw materials used in their manufacture. The products include the! following: (1) clay prorlucts -such as facing brick (glazed and unglazed), common brick, facing tile (glazed and un-glazed), terra cotta, load-bearing tile, non-load-bearing tile, structural clay floor tile, quarry tile, drain tile, sew-er pipe, conduits .and flue liners -which are made mainly from domes-tic common clays and shales and from domestic or imported stoneware clays and low-grade fire clays; (2) floor and wall tiles of the whiteware type, which are produced from ingredients such as kaolin, ball clay, feldspar, nepheline syenite, talc, pvro-phyllite and wollastonite; (3) glass products -the major ones being sheet glass, plate glass and mineral wool (glass wool, and rock or slag wool) -which are made from such materials as silica sand, soda ash, salt cake, feldsspar, nepheline syenite, dolomitic limestone, high-calcium limestone. borax and (for rock and slag wool) various rocks or slags;

Jan 1, 1963

By M. S. Badollet

"IntroductionASBESTOS FLOATS may be defined briefly as blends of air-borne particles of fibrous asbestos and dusts produced during the milling stages and collected by Cottrell precipitators, dust sheds, or bag-houses.The various grades of asbestos floats on the market contain fibrous asbestos particles ranging in length from microscopic to approximately 1/4-inch. The fines or dusts present in the floats are from 40 microns to 2 microns or less in cross-section.Airborne asbestos particles are of diverse length because they are collected at numerous places in the mill. There are: (1) dusts removed from dry rock storage bins, (2) dusts removed from rock and fiber screens, (3) particles from the tops of collectors, and (4) fines removed by suction from the processing equipment. Sometimes the airborne particles are kept segregated, so that there is a partial separation by gravity. This is accomplished by a series of dust chambers enclosed in a long, rectangular building. The longest and heaviest particles fall nearest to the air flow entrance, the smallest at a point farthest away and nearest the exit. Sometimes the air from the dust chamber building is passed through a series of bag-houses or electric :precipitators ,to collect the extremely fine particles which normally escape to the atmosphere."

Jan 1, 1952

By Michel L. Bilodeau, Brian W. Mackenzie, Dallas W. Davis

"The paper formulates an evaluation procedure for examining the effects of location on the economics of developing mineral deposits. This methodology is applied to assess locational aspects of Nova Scotia's competitive position f or mine development relative to other Canadian regions and provinces. The appraisal concerns two representative mine development opportunities, a medium-size open-pit tungsten deposit, and a small underground gold deposit. The influence of regional economic conditions is initially assessed. Then, the consequences of taxation are isolated. Finally, the combined impact of regional and taxation conditions is examined. SettingThe economic potential of mining may be assessed in a number of ways. One approach, increasingly used for both corporate planning and government policy purposes, is to evaluate the competitive position of an actual or potential mineral producer in the international marketplace relative to other suppliers.Such examinations of competitive position vary from cost league comparisons of breakeven costs for operating mines, through the assessment of medium-term costs associated with developing new mine capacity, to long-term evaluations of the economics of mineral supply from the start of exploration. The complexity of the analysis increase s with the scope and timeframe of interest. Many factors are involved. One component of competitive position is the quality of the mineral resources available. Other key factors include existing technology, wage and salary rates, labour productivity, the cost of capital, infra structure requirements, distances from sources of materials supply an d to mineral markets, management attributes, organizational efficiency, government mineral policies (particularly taxation), and inflation and exchange rates. The paper fits within this competitive position framework.The variable economic conditions which exist within Canada have a direct bearing on the viability of mine development and, thereby, on mineral exploration potential. The paper examines locational aspects of Nova Scotia 's competitive position."

Jan 1, 1986

By B. A. Zaharov, J. M. Shneerson, L. V. Chugaev, M. T. Zhunusov, A. M. Markelov, S. V. Drozdov

The main direction of research was the application of autoclave technology for the flotation concentrates or biooxidation feedstocks. The industry modernization also expects the possibility of increasing the yield of the flotation concentrate, to allow an increase in gold extraction in flotation circuit. This paper provides brief description of results obtained for concentrates with the yield of 4 and 8%, as well as corresponding biooxidation feedstocks. Technological efficiency of autoclave oxidation is shown for both concentrates and biooxidation feedstocks. The process has been evaluated on a laboratory and a continuous pilot plant scale. Gold extractions from POX discharge are ranging from 94-97% for each product, with only 5-7 kg/t cyanide consumed.

Jan 1, 2014

By G. E. Norman, A. L. Mckague

"The new smelting process commenced operation in 1978. The pelletizing and sinter plants were replaced with slurry-fed roasters and the blast furnaces with electric furnaces. The existing converter aisle and matte handling facilities remained unchanged.Process DescriptionNickel-copper concentrate is partially roasted in two slurry-fed fluid bed roasters. After gas cleaning, the sulphur dioxide gas is transferred to the acid plant. The roaster product is conveyed to two electric furnaces for smelting to produce a waste slag and furnace matte. The slag goes to the disposal area and furnace matte containing the metal values is processed in the converters for further removal of iron and sulphur.The final matte containing about 75 per cent metal values is shipped to the refinery in Norway.The commercial smelter was designed for 2135 tonnes per day of concentrate, with an availability of 85% . Roasters and electric furnaces were sized at 117 per cent of design, or 1250 tonnes per day on each of two lines. Concentrate storage capacity in the plant is sufficient for two to three days' plant operation.The new smelting process will be discussed under the following headings:Concentrate Slurry HandlingFeed PreparationRoaster OperationRoaster Gas CleaningCalcine TransferElectric Furnace Operation and Process Control Converting and Matte HandlingUnder these headings, process control , equipment changes, and plant performance after three years' operation is reviewed. A brief discussion of accident prevention , and working environment is also included ."

Jan 1, 1984

By Biplop Das, E. Herrera, A. Burrows, P. J. Mackey, G. R. F. Alvear Flores

Since the first commercial plant was built at Mount Isa, another twenty ISASMELT™ furnaces have come into commercial operation, and construction of new plants continues. The primary copper ISASMELT™ top submerged lance (TSL) technology continues to attract interest from potential users who seek to smelt productively. In addition to the known benefits of productivity and flexibility, ISASMELT™ operators have also achieved improvements to energy efficiency when switching from their previous technologies. The recent production statistics for operation at Tuticorin, India show that ISASMELT™ has taken the first steps into territory beyond 400,000 t/y (copper cathode basis) and this will likely be the scale chosen by future new copper smelters operating purely on a toll smelting basis. Highly energy-efficient technologies will be expected at these smelters

Jan 1, 2015

By Jacque Trottier, Marcel Vallée, Gratien Gélinas

"Mineral exploration in Canada traditionally has gone from boom to bust in cyclical pat-terns following market and discovery cycles, but other endemic factors related to exploration financing and performance have contributed to the amplitude and recurrence of these fluctuations. In view of these problems, junior exploration is reviewed here in a marketing perspective, looking at the 4 Ps: Product, Price, Placement and Promotion.In the 1980s, MEDA incentives gave the shares of junior and mining companies significant price and promotion advantages, and contributed to excessive exploration funding. Many were thus led to minimize the basic values needed for continued investor interest: appropriate levels of product quality, sustained share value and customer satisfaction. Basic changes are needed to improve the marketing of junior mineral exploration in the future, with or without improved fiscal incentives. To be successful, the required improvements must come from the technical participants, but the financial partners also need to be involved.Exploration in Canada must be marketed with vigour, both in Canada and internationally. Exploration, mine development and mine production are essential to our economy. They are environmentally acceptable and they are welcome in Quebec and in most Canadian provinces and territories. Canadian exploration and mining are entrepreneurial industries that must take better advantage of their strengths and achievements and remove the shortcomings that hinder them: nobody can do it for them!"

Jan 1, 1996

By Iwueze Anaekperechi Rose

The International Labor Organization has declared mandatory adequate provision of safe workplace and safety for all workers in all occupations including the mining sector. Early scientists like Agricola (1559) who studied the health of Miners, found that there are peculiar health problems associated to their work and working environment. This unsafe working condition was one of the major factors that resulted to the Industrial revolution in England and eventually led to the establishment of regulations and laws guiding operations in all workplaces and workers in England and all over the world. Recent studies by Heinrich suggested chains of events of safety issues in the mining sector. Occupational injuries, accidents and ill health have huge social and economic implications on workers, their families and communities. Top mining top issues are respiratory diseases, noise, explosives, ventilation, fire, and explosion. However, one of the principal mechanisms for achieving Occupational Health and Safety (OHS) goals and mapping the future is government regulations of employers. In Nigeria, the situation is not different; mining operations are equally hazardous and have far reaching implications. In 1995 the Ministry for Solid Minerals was established to focus on the development of other categories of mineral products ranging from gold, coal, uranium, and tantalum deposited across the country. Prior to this an Act of Parliament Act Cap 121 of 1946, was in place to regulate amongst other contents mining safety. This was subsequently reviewed following the incidence of Lead poisoning resulting from small scale miners processing gold ore highly contaminated with lead in Zamfara state (northern Nigeria). Hundreds of children died as a result of exposure to lead poisoning, it was clear that the regulations were not sufficient (details to be discussed). However, advances have been achieved in mining engineering since then. A review team was constituted to provide a more stringent law to regulate mining operations in Nigeria. The strategies for mapping the future of OHS in mining engineering will employ amongst others setting and adopting ISO/ILO standards and enforcement; providing technical assistance; and establishing sustainable developmental structures as surveillance and compensation. The management systems approach was also developed as a result of cases of accidents. The accepted international standards guidelines and requirements will be proposed. Furthermore in mapping the future for Mining Engineering, it is suggested that most countries have their own management strategies and legislation to improve safety of workers through greater consistency and efficiency of OHS programs. Some American researchers came up with the Safety Engineering Model. The Australian Mining Council of mineral and petroleum resources after the Catastrophic Maura Disaster developed the National Mine and Safety Framework. In Canada, after the Hillcrest mine disaster in 1914, Allan shaft coal mine catastrophe in 1918, Westray mine explosion in 1992 and other disasters, Occupational Health and Safety Act R.R.O 1990 was sufficiently developed to provide adequate safety conditions and standards. In Nigeria after the disastrous Zamfara lead poisoning, which claimed the lives of hundreds of children due to exposure and lack of appropriate safety measures, stringent measures were developed by the federal ministry of Justice to address and regulate mining process in Nigeria.

Aug 1, 2013

By Daniel E. Walsh, P. D. Rao

"A four-inch compound water cyclone (CWC) was tested to evaluate its gold recovery characteristics when processing -4.8 mm run-or-pit, placer material. Neutron activated placer gold particles (840 to 37 microns) were used as radiotracers (/98Au) in a closed circuit ewe test loop to determine concentrator recovery; a procedure believed unique to this study. The effect on gold recovery of gold size and shape, feed pulp density, feed pressure, vortex finder clearance (VFC), ewe cone type, top-size of the feed solids, presence or absence of heavy minerals in the feed, and the quantity of-37 micron slimes in the feed was investigated in over 300 tests.CWC concentration ratio and the top-size of the underflow solids were both affected by cone type, VFC, and feed pressure. Gold recovery was significantly affected by gold size, gold shape, and concentration ratio. These effects are complex, because significant size-concentration ratio and size-shape interactions exist. Radiotracer techniques showed gold particles had a residence time within the ewe of approximately one second. This study suggests ewe gold recovery is a concentration. This work suggests ewe gold recovery is a function of particle size and shape, and the flow rate through the cyclone. CWC cone ""bed density"" is considered important only as a thin, protective layer, which shields coarser gold particles from the entraining currents and facilitates their movement through the CWC.IntroductionCompound water cyclones (CWC), or automedium cyclones, are enhanced gravity concentrators for the beneficiation for slurries of sand, coal, and ground ore (Fig. 1). They are called compound water cyclones because of the compound slopes of their basal cones (Fig. 2) and are operated to suppress classification phenomena in favour of gravity concentration effects. The compound water cyclone is not a new wet concentrator. It was developed in the late 1950s by Dr. Jan Visman through research sponsored by Canada's Department of Energy, Mines, and Resources. Since that time, it has become a common unit in coal washeries for cleaning fine coal. CWCs and other versions of concentrating cyclones have also shown promise for heavy minerals and precious metals recovery."

Jan 1, 1988

By H. H. Fairfield

THE production and inspection of the materials of war involves thousands of observations. Logical action is generally based on the interpretation of many observations. The success of such action depends upon the accuracy of the observations and the soundness of the interpretation placed upon them. There are countless instances where the observer 'sees but perceives not'; that is, the significance of a group of observations is lost, due either to faulty interpretation or to no interpretation at all being placed on the results. This condition is being partly corrected in the United Kingdom and the United States (1) by the promotion of certain principles by Ordnance officials. The term Quality Control has been adopted to describe a system of studying and controlling industrial products by methods of handling observations. In these pages an attempt is made to outline in a non-technical manner some of the ideas used in the handling of observations. Of course the authenticity of the observations determines the worth of any decisions based on them. No matter how brilliant is the theory built on unreliable sampling, it is usually of little practical value. n some fields it is almost impossible to obtain observations free from bias. Let us suppose that observers of speed in miles per hour were available for judgment: (a) a bystander, (b) a motorcycle policeman, and (c) a motorist accused of speeding. The bystander might be unbiased but probably would be very inaccurate. The motorist is usually biased on the low side. The policeman is the only qualified observer and, if over-zealous, he might be biased on the high side. Conclusions drawn from large numbers of biased observations naturally would be of little value.

Jan 1, 1943

By J. R. Morris

"A hoisting plant design should satisfy two basic requirements:1. to provide the necessary materials handling capacity, including ventilation where applicable, while meeting the requirements of good practice and, as a minimum, government regulation; and2. to optimize the economics of the project. Selection of hoisting equipment to meet the first objective is a complex but logical engineering process. The necessary calculations of payloads, accelerations, speeds, rope strength, hoist size, and power requirements are very readily carried out on computers or programmable calculators. A variety of hoist options can be quickly examined to assess the effects of changes in design parameters.Meeting the second requirement involves balancing the costs of various hoist arrangements and shaft designs, together with the time cost effects of differing shaft sinking rates and potential advances to be gained by concurrent level development. The proposed mine layout is significant here, as is the possibility of future shaft deepening and/or production increase. The availability of used equipment may be significant, both as regards first cost and delivery time. The factors are interactive, with their relative effects .varying from project to project. This paper sets out the primary factors to be considered."

Jan 1, 1990

By R. C. A. Thurston

"The lack of notch ductility in structural steel in general, and in ship plate in particular, has been the object of widespread attention in the metallurgical world since the spectacular collapse of the ill-fated S.S. Schenectady in 1943. Numerous investigations have been carried out, many new tests have been developed, and a vast amount of useful data has been published, with the result that our knowledge is now far more advanced than it was at the time of this disaster. Interest has focused largely on the medium strength steels, and the various factors which cause a normally ductile steel to behave in a brittle manner in the presence of a notch and at relatively .low temperatures have been thoroughly studied.The literature available on high-tensile steels, however, is less extensive and the present paper is intended to supplement this information. Notch toughness tests have been carried out, at the request of the R.C.N., on a high-tensile manganese steel in the form of commercial ship plate. One of the newer tests, the tear test, and the Charpy V-notch impact test, were used to examine the characteristics of plate for the construction of an ice-breaker. About 250 plates, mainly in the thickness range from 11,4 in. to 1 % in., were tested. An an-alysis of the results obtained is presented, certain aspects of the tear test are discussed, and the correlation between the two types of test is studied. On the basis of information available from casualty ships, the plates, with few exceptions, were considered to be satisfactory."

Jan 1, 1959

By M. Gimpel, R. Galler, T. Antretter, H. Kargl, R. Tichy, W. Ecker, M. J. Mikl-Resch, G. Pittino

"A computational method based on a continuum-mechanical approach to simulate rock cutting is developed and evaluated. The aim is to obtain the local loading acting at the cutting pick during operation. The explicit FEM is chosen to model the pick-rock interaction. The presented method takes advantage of (i) an advanced material model (ii) a robust contact algorithm and (iii) fast calculations due to parallelization. A damage-plasticity law is chosen and modified with user-subroutines. A user integrated element deletion routine evades critical mesh distortions. Infinite elements at the model boundaries avoid unrealistic deformation wave reflection.INTRODUCTIONExcavation in mining and tunneling is a costly and complex process. Special equipment such as the roadheader (Figure 1) is employed to cut the rock in the excavation process but high material strengths limit their usability (Tockner 1999). Nowadays a challenge is to extend their field of application to harder and more abrasive rock materials. The forces on the pick (Figure 2) are of great importance and determine wear and especially the efficiency of the machine. Figure 2 shows the principle of cutting and the predominant forces. The variation of pick geometry, cutting depth or attack angle will result in an alteration of these forces and determine the efficiency of the process (Tockner 1999). The mechanisms of rock cutting follow the principle of indentation (Kou et al. 1999). Directly under the indenter a hydrostatic stress state evolves causing the material to fail only due to crushing and fragmentation mechanisms. In the close surroundings large strains emerge and tensile cracks are formed but in a further distance the material behaves elastically."

Jan 1, 2015

By S. Mostaghel, V. Hernandez, S. Ge

"The automotive industry is under a constant pressure to reduce the weight of vehicles in order to reduce emissions and improve fuel efficiency. As such, there is an ever-growing demand for high strength and high ductility steel grades to meet the need for lightweight automotive components. Over the past decade, the production and application of 2nd and 3rd generation Advanced High Strength Steels (AHSS) as a lightweight material in automobiles has gained significant popularity due to their exceptional mechanical properties. However, the production cost of these high manganese steel remains high, partially due to the need of large amounts of ferromanganese as alloying material in standard steelmaking processes.The current study introduces a new and cost-effective technology for the production of medium- and high-manganese steels, where self-fluxed micro-pellets of manganese ore will be used as the source of manganese that can be injected into the steel bath. Prior to injection, these pellets are subjected to a pre-reduction process using a mixture of H2 and CO gases, where partial metallization of iron and manganese will occur. Direct injection of the pre-reduced micro-pellets provides less volatilization/emission and higher recovery of manganese, and is capable of producing AHSS with 6–18 wt% Mn.INTRODUCTIONAutomakers are constantly searching for lighter, stronger and cheaper materials in an effort to create safer and more fuel efficient vehicles. The introduction of aluminum alloys and polymer composite materials for automotive applications has been carving into what is traditionally one of the most profitable markets of the iron and steel business. The steel industry responded with Advanced High Strength Steel (AHSS)—a family of manganese containing steels which exhibit exceptional strength and ductility."

Jan 1, 2016

By L. V. Kin, V. V. Lodeischikov, A. V. Byvaltsev, IRGIREDMET JSC, O. D. Khmelnitskaya, S. V. Petrov

"Irgiredmet Institute carried out the study on the development of gold recovery technology from refractory ore from a Russian deposit. The ore contained 1.1 g/t Au, 1.5% of pyrite and 2.4% of pyrrhotite. The recovery of gold achieved was 84.7% using gravity with generation of high grade recoverable gold concentrate and gravity middling. In the course of lime treatment, cyanidation of the middling followed by tailings detoxification the consumption of reagents was 13.0 kg/t CaO, 95 kg/t NaCN and 72 kg/t Ca(OCl)2 of the concentrate. This was capital intensive.In order to decrease the consumption of reagents, magnetic separation of the middling of the concentrates from gravity separation was added to this flow sheet. Pyrrotite recovered to magnetic fraction, which did not contain gold in accordance to this advanced flow sheet. The mass yield of pyrite goldbearing non-magnetic fraction decreased down to 1.5 times in relative to gravity middling. The slurry filtration prior to and after cyanidation allowed the organization of cyanide solution recycling.The results of pilot plant tests using the developed flow sheet showed that the content of pyrrhotite in the non-magnetic fraction decreased from 59.1% to 11.3%. The reagents consumption was 12 kg/t CaO, 3 kg/t NaCN and 16 kg/t Ca(OCl)2 of the pyrite concentrate. The total gold recovery using this flow sheet was 83.4%. Due to a decreased consumption of reagents, cost efficiency of the process was achieved. Based on the results of this research, a project design criteria was developed. A processing plant with the annual throughput of 2.6 million tonnes of ore is being designed."

Jan 1, 2016

ABSTRACT Understanding process histories and worker exposures in nickel production operations is critical in determining the role nickel compounds play in respiratory cancer incidence. As part of a series on Vale Canada’s (previously known as Inco) nickel processing operations, this paper includes descriptions of Ni electrolytic operations at refineries in Port Colborne, Ontario (1922–1984), and Thompson, Manitoba (1961–present). Industrial hygiene measurements, by area and personal sampling, of workplace aerosols at these operations are reported.

Jan 1, 2014