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By Richard F. Lynch, Frank E. Goodwin

"The development of Galfan, a new generation 95% zinc-5% aluminum-mischmetal alloy coating for steel, offers opportunities for greater fabrication flexibility and upgraded corrosion performance in automotive applications. The formability of Galfan is equivalent to that of electrogalvanized steel, based on laboratory tests and automotive component fabrication. Corrosion resistance of Galfan exceeds that of hot dip and electrogalvanized, including performance in automotive industry tests. Automotive production applications for deep drawn and stamped components in France and Germany are based on the ability to meet dual performance requirements for upgraded formability and corrosion resistance. The first U.S. Galfan application was on 1985 model Ford cars and light trucks for transmission oil cooler lines which has now expanded into a number of power steering tubing uses. IntroductionContinuing requirements for improved vehicle performance coupled with the ever present need for reduced cost have spawned the development of a number of new coated steel products. Among this new generation of coated steels is Gaifan™, a 95070 zinc-Solo aluminum-mischmetal hot dip alloy coating. Galfan exhibits particular promise for automotive use based on broad fabrication advantages and upgraded product performance(I ),The unique characteristic of Galfan is the key combination of greatly improved formability with much longer corrosion life. Galfan provides significantly better formability than any other hot dip coating. Testing shows that formability is limited primarily by the steel substrate to which the Galfan coating is applied. Galfan exhibits excellent resistance to flaking and microcracking during commercial forming operations. The result is the elimination of unnoticed damage to the coating which would show up later as premature rusting on the finished product."

Jan 1, 1987

By P. Amelunxen

It is well-known that the particle breakage mode that occurs in a semi-autogenous mill is significantly different from that which occurs in a ball mill, enough so to warrant very different lab scale breakage tests and scale-up models. This phenomenon, at the plant scale, leads to changing process constraints depending on the particular properties of the ore. For example, hard or coarse ores might bottleneck the SAG/AG mill throughput, while the ball mills might constrain throughput when milling soft or fine ores. Because the power draw of a ball mill is fairly constant compared to that of a SAG/AG mill, periods of SAG/AG mill bottlenecks lead to increased ball mill circuit specific energy consumption and a finer grinding circuit product size, which together constitute a loss of efficiency of the overall process. Because HPGR circuit throughput is less sensitive to changes in ore hardness, this situation is less common or severe in those circuits. Furthermore, the ball mills are somewhat decoupled from the upstream crushing circuits through the use of surge bins, which also helps to mitigate this effect. As a result, ore hardness variability constitutes a significant cost penalty that should be applied to SAG mill/ball mill/pebble crusher SABC circuits when evaluating the relative economics of different grinding circuit configurations. Nevertheless, the issue is by-and-large ignored, because most current HPGR trade-off studies are based on averaged ore hardness parameters. This paper provides an estimate of the magnitude of this penalty for a typical operation by using Monte Carlo simulation methods and plant data from Freeport-McMoRan?s autogenous, semi-autogenous, and HPGR-based comminution circuits. A case study from an in-house 96K t/d sulphide project is presented to illustrate the concept. It was found that by including variability effects, the trade-off NPV of the HPGR circuit over that of the SAG mill circuit increases to $84 million from negative $33 million, effectively reversing the original decision of selecting a SAG mill circuit for the fixed hardness case.

Jan 1, 2012

By C. Lambert

It has been shown that contacts between host rock and engineered barriers may be critical in the design of deep radioactive waste repositories. Water is expected to reach the interface zone after the re-saturation of the geological massive and its presence may lead to concrete leaching. Such a phenomenon could increase the interface transmissivity and compromise the confinement of radioactive waste. Recent experimental results from Buzzi et al. (2008) have enhanced how concrete leaching can drastically change the mechanical behaviour of such interfaces. Because of the local loss of strength resulting from leaching, shearing resulted in a degradation of the interface asperities. Similarly to rock joints, intact interfaces exhibit a usual contracting-dilating behaviour. On the contrary, depending on the extent of leaching, the degraded interface can display a fully contracting. This paper intends to investigate the influence of concrete leaching on the mechanical behaviour of host rock-concrete interfaces. The leaching process consists in the dissolution of some of the hydrates of the cement paste, leading to a reduction of the strength and Young's modulus. A discrete model has been developed with PFC3D where a simplified interface morphology has been introduced using a saw-tooth description of the asperities.

May 1, 2009

By I. I. Betcherman

INTRODUCTION A DISTILLATION process offers one of the most effective methods of refining metals. Its use is particularly attractive in the case of reactive metals which are not readily treated by pyrometallurgical or electrolytic methods. The 1ow vapour pressure of most metals severely restricts the applicability of the disti1lation process and only one or two metals may be effectively treated under atmospheric pressure at a reasonable temperature. If operations are carried out under reduced pressure several additional metals may be effectively distilled. Table I shows the vapour pressure of a number of metals together with a value of the free energy of formation of their ?oxides. Zinc and cadmium head the list and for many years? they have .been effectively refined by distillation. Sodium, magnesium, and calcium follow in descending order, and they may be distilled readily in vacuo and with difficulty at atmospheric pressure. Sodium, which is not of great metallurgical interest, is not considered. Magnesium has recently been produced in considerable tonnages by distillation methods ( 3). This paper describes the vacuum distillation of magnesium and calcium, their separation from each other, and their separation from less volatile impurities.

Jan 1, 1951

TABAKOTO / SEGALA ? Annual gold production approximately 100,000 oz ? Debt free ? Unhedged ? Combined surface reserves 949,000 oz ? Combined 9 year life Tabakoto open pit reserve 568,000 oz (3.4m tonnes @ 5.26 g/t Au) Segala open pit reserve 381,000 oz (3.98m tonnes @ 2.98 g/t Au)

May 1, 2006

By S. N. Yu

Tele-operation manipulators applied in this paper are systems for the remote handling and management of pyroprocessing related facilities in an Argon cell of the KAERI (Korea Atomic Energy Research Institute). Generally, these kinds of systems are composed of a master-slave system and its peripherals installed along the wall of the cell, with the master transmitting the user?s own motion to the gripper directly. This study introduced various considerations and modifications to improve the remote handling performance. The analysis of an operator's ability using his/her own upper arm motion range while manipulating the MSM, and considerations of its manipulation margin and the related tool modifications are also included. Finally, the test results of several remote handling tasks are presented, and an adequate operation strategy for the tele-operation system of hot-cell type facilities is proposed.

Aug 1, 2013

By Jonas Olsson

"The picture of China as an antiquated continent is changing rapidly and fast-forwarding progress is a fact in most infrastructural fields. Mining is not an exception. China is today the largest producer of aluminum, coal, steel, zinc, tin, lead and manganese and the country’s mineral resources comprising approximately 12% of the global reserves ranks them number three in the world after US and Russia.In order to feed the growth industry is needed to take extra ordinary strides to improve supply of raw material and Chinese mines are continuously being upgraded with the latest western technology to meet the increasing domestic demand of base metals.In Anshan located in China’s northeast province Liaoning we find one of the fastest developing mining companies, Angang Iron & Steel Group Co. Ltd. With their six mines that together process approximately 60 M ton iron ore/year Angang Iron & Steel Group Co. Ltd is the largest iron ore company in China. The group’s thorough pre-studies and technical evaluations over the past five years have made them very successful in both plant upgrades of existing operations and green field projects.INTRODUCTIONWe live in a time when the world market is gradually acclimatising to the global consequences of “The China effect”. An effect caused by a formerly sleeping giant nation that during the last years has awakened and developed beyond comparison, primarily because of booming infrastructure projects and demand for capital and consumer goods"

Jan 1, 2006

Overview ?Oil Sands Background ?Water Use in Surface Mining ?Tailings Disposal ?Water Balance for Surface Mining ?Implications of Emerging Regulations ?Water Management Framework ?Tailings Performance Criteria (Directive 074)

May 1, 2009

By C. McLachlan, J. R. Donald

"Positioned at the forefront of the seafloor minerals industry, DeepGreen Resources is on track to becoming a leading producer of base and strategic metals obtained from vast high-grade seafloor polymetallic nodule deposits. DeepGreen believes the seafloor minerals industry is an opportunity for developing a more environmentally and societally attractive way to produce cleaner base and strategic metals. Polymetallic nodules contain nickel, manganese, copper, cobalt and other base and strategic metals. Polymetallic nodules represent an exceptional multi-metal-bearing resource, and no current metallurgical operation or flowsheet exists that can recover the primary metallic values while managing the distinct mineralogy. DeepGreen Resources is developing a new process to maximize the business outcomes consistent with the highest environmental standards, including targeting a near zero waste facility. The present paper discusses the history, context and driving forces of polymetallic nodule project development. An overview of DeepGreen?s Nauru Ocean Resources Inc. (NORI) project is presented along with a literature review of polymetallic nodule processing and the on-shore project development scope and plan at DeepGreen Resources is outlined.INTRODUCTION AND CONTEXT Polymetallic Nodules in the Clarion-Clipperton Zone Containing nickel, cobalt, copper and manganese, polymetallic nodules occur in most oceans of the world. The nodules lie on the seafloor sediment. The largest deposit in terms of nodule abundance and metal concentration occurs in the Clarion-Clipperton Zone (CCZ) on vast abyssal plains at a depth of 4,000 to 6,000 metres. The CCZ is located almost entirely in international waters as presented in Figure 1. It has been estimated that the CCZ contains (International Seabed Authority, 2010): •,>21 billion tonnes of nodules; •,>270 million tonnes of nickel; •,>6 billion tonnes of manganese; •,>234 million tonnes of copper; •,>46 million tonnes of cobalt. There are several active hypotheses for the mechanism of formation of the nodules including precipitation, hydrothermal decomposition of basaltic debris, and involvement of microorganisms. Nodules require a nucleus to start forming, which could be a piece of pumice, a shark tooth, old nodule piece, basalt debris or even microfossils like radiolaria and foraminifera. Nodules form concentrically with layers of iron and manganese hydroxides around a core. Although composed mainly of Mn, Fe, silicates and hydroxides, it is the significant content of Ni, Cu, Co, Zn and Rare Earth Elements (REE) that is generating the economic interest in harvesting these deposits. Nodules vary in size from micro-nodules to about 20 cm, the common size being two to eight centimeters. A typical polymetallic nodule and polished cross-section is presented in Figure 2."

Jan 1, 2017

By M. Holmes, R. Molnar, E. Norton, K. Baxter, J. Riordan

The Boleo Copper-Cobalt-Zinc-Manganese Project of Baja Mining Corp. is situated adjacent to Santa Rosalia on the Baja Peninsula of Mexico. The El Boleo ore is a mixed oxide-sulfide deposit with major values in copper, cobalt, zinc and manganese. The metallurgical process designed to treat the El Boleo orebody involves a sulfuric acid leach in seawater using oxidative and then reductive leaching to maximize metal extraction. The leach solution is separated from the barren solids via counter current washing through a series of high rate thickeners. Copper is recovered using conventional SX-EW processing as cathode. Zinc and cobalt are extracted from the copper SX raffinate after iron and aluminum precipitation. The CSIRO DSX solvent system (Versatic® 10 and LIX® 63 mixture) are used in this extraction. Manganese remains in the DSX raffinate and is recovered by soda ash addition as a high quality manganese carbonate precipitate. Zinc and cobalt are acid stripped from the loaded DSX solvent. Zinc is then re-extracted away from cobalt using Cyanex® 272 extractant and stripped into a highly concentrated strip liquor (+100 g/L Zn) and directed to either a spray dryer or a granulator for production of zinc sulfate monohydrate. The zinc solvent extraction raffinate, containing cobalt, advances to another SX circuit using Cyanex® 272, for the recovery of cobalt as cobalt cathode. In this paper, the detailed results from bench and integrated pilot plant testing for zinc recovery from the El Boleo ore will be described. The results of this testing are currently being used to engineer the commercial plant at El Boleo.

Jan 1, 2008

By J. Gordon Parr, D. A. Whitaker, G. A. Yorko

High purity alloys of zinc with 25 per cent to 50 per cent aluminum, have been prepared. Mechanical properties of the as-cast and heat-treated alloys have been related to constitution, determined by x-ray diffraction and microscopic methods. Investigations include the effects of aging and of small nickel additions on the properties of the alloys.

Jan 1, 1960

By Deon van Tonder, Chuck Edwards

"Solvent extraction is used in many acid leach uranium circuits to upgrade and purify the uranium bearing solution prior to final product precipitation. A number of strip options are available to recover the uranium from the loaded organic. This paper compares some of these options on the basis of typical capital and operating costs for both the solvent extraction circuit and downstream uranium processing, and also considers other related issues. The aim is to provide an objective comparative assessment of these options that could be used as a qualitative guide in process selection or improvement.INTRODUCTIONIn the 1950s the uranium industry was the first industry to adopt solvent extraction (SX). Since then, the flow sheets have advanced. Notable was the introduction of tertiary amine extractants by General Mills during the late 1950s and 1960s (Mackenzie, 1997; Mackenzie, 2005), which is still today considered ‘state of the art’ technology. Initially solvent extraction was done in combination with ion-exchange, such as in the Eluex flow sheet, followed later by the adoption of direct solvent extraction from pregnant leach solution (PLS). From a strip-precipitation perspective ammonia strip followed by ammonium diuranate precipitation was widely adopted as the norm in the uranium industry. More recently alternative strip systems have been receiving increasing attention due to the environmental, health and safety issues associated with ammonia and the resulting calcined uranium oxide product. This paper explores some of these alternative options in comparison with the ammonia route.It is important to acknowledge that each operation is unique, and therefore the information and philosophy outlined in this paper serve to provide a general guide that can be potentially applied and adapted to any site or project."

Jan 1, 2013

By W. E. Oching, M. M. Ghomshei

"Collaboration among Ventilation Engineers, Mine Inspectors, worker representatives, health and safety officers and management is key to an effective operational mine ventilation management. Mine ventilation training, ventilation survey reports for mine stakeholders and interaction with mine frontline workers and management concerning safety, energy saving, assets management and maintenance are effective tools in implementing best industry practices and significant reduction of ventilation operating costs without compromising safety. These approaches may not be new to well established mining companies but the real dilemma is how to implement them effectively and this is what this paper will address.INTRODUCTIONManaging an effective mine ventilation system is becoming increasingly challenging, especially during tough economic times in the mining industry. Management strives for more production while frontline miners work hard to surpass the production targets, thus improving their incentives and above all aiming to enhance the prospects of their job security when the mining industry is facing challenging times. Taking shortcuts by not fully following the safety regulations or industry best practices are often notable, resulting in the rise of Workers Compensation Board claims and temporary shutdowns of active workings, compromising productivity and increasing the operating costs.In accordance with the Mines regulations in various jurisdictions in Canada and the US, it is evident that companies adhere to establishing basic ventilation management systems through the provision of the code of practice, procedures, work practices and standards/guidelines. This is aimed at ensuring the health and safety of underground workers (de Souza, 2017). However, the challenge to many operations is the improper implementation of the mine ventilation regulations including some managers showing reckless disregard for workers safety by focusing on production and not worrying to address ventilation problems (Steven & O'Keefe, 2010). Other challenges facing effective ventilation management include inadequate training of frontline workers on ventilation system and hazards associated with poor ventilation systems such as toxic gases, dust, heat, and underground explosions (Mufson et al., 2010; Suvar et al., 2017); friction between mine managers and the mine inspectors (Mufson et al., 2010), improper maintenance of ventilation system and inventory management, among others."

Jan 1, 2019

By Orlando C. Gaspar

Abstract - The presence of fine-grained mineral intergrowths, the complex distribution of deleterious minor elements, and the variable base-metal contents in some assemblages commonly pose technical problems for the processing of volcanogenic massive sulfide ores. The beneficiation of most massive sulfide ores from the Iberian Pyrite Belt requires extremely fine grinding to liberation sizes of K80 = 15 µm to 25 µm. For several deposits, mapping of the ore types and metal zoning patterns has shown that the different ore types are distributed as ore lenses within the massive sulfides. Mineralogical, textural, and metallogenetic studies have provided an understanding of the distribution of both the vertical and the horizontal metal zonation in the orebodies. Because the efficiency of ore processing is affected by ore textures, and because the same mineral commonly has different textures and varies in chemical composition, a relationship between textures of the feed and the middlings must be established for all ore types defined at the deposit scale. Quantitative mineralogical methods have been developed to provide, on a timely basis, the information needed to optimize the concentration processes for the massive sulfide ores at the Aljustrel and Neves-Corvo deposits, Iberian Pyrite Belt, Portugal.

Jan 1, 1997

By R. D. Mollison

"Ecstall Mining Limited was formed to operate the Kidd Creek mine, discovered by Texasgulf Incorporated in 1961 the orebody is geologically very complex, containing rich values of zinc, copper, silver and lead. The first phase of the operation involved an open pit, railroad and concentrator complex, which was under construction in 1965 and began operations in late 1966. The open pit, with rim dimensions of 2,000 by 1,000 feet, was computer-designed and highlights excellent wall control and efficient ore extraction and grade control. The railroad was built over the worst type of muskeg country, but it has been well maintained, resulting in an uninterrupted supply of ore in the trains. The 10,000-tpd concentrator, located 17 miles from the mine, is highly instrumented and automated. It features computer control of reagents and, in addition to the copper, zinc and lead flotation circuits, has a modern gravity tin plant. The concentrator is large, because very fine grinding is required for good metallurgy and nearly 2,500 tons per day of concentrates are produced. In 1969, work was started on the underground mine to take over from the open pit; it began partial production in mid-1973. The mine is highly instrumented, has a ramp from surface, a high-production shaft, an underground gyratory crusher and an efficient orehandling system, and employs the latest mining techniques. The electrolytic zine plant, rated at 120,000 tons of slab zinc per year, started operation in April, 1972, with batch leaching and purification circuits. It has been converted to continuous leaching and is now in the process of converting to continuous purification. Further modernization and automation will be carried out in the next few years. Five service departments support the five operating departments. These are maintenance, engineering and technical services, geology, administration and employee relations. How these ten departments function and work together using the most advanced technology to produce an efficient operation is the main theme of the Ecstall Story."

Jan 1, 1974

By S. Espley, G. Tan

"Inco's Little Stobie Mine is a low-grade nickel operation producing approximately 4()()() tons per day. Backfill has never been an economical option at the mine; therefore, the only viable type of mining in the upper zones has been by sub-level cave. This mining method allows for the draw-down of a rock cover into the empty stopes to provide stability to the over-all rock mass. In the lower areas of the mine, bulk blasthole mining methods have taken place, without rock fill, resulting in extremely large open stopes. As the mine reaches its final stage of recovery, it is inevitable that the hangingwall of the large voids will undergo tensile failure via spoiling.This paper deals with the collaborating efforts of Inco's Rock Mechanics group and the Little Stobie mining operations toward the successful recovery of the ore zone remnants such that the inevitable failure, and time of failure, of the rock mass is ""controlled"". Within the mining scheme, several key requirements had to be met to satisfy the operations: (1) production rates; (2) good blast fragmentation; and (3) secure pulling-horizons. A full-scale rock mechanics study was carried out involving: numerical modelling studies; pulling ellipse analyses; blast design, monitoring and analyses; laser profiling; and time domain rej7ectometry (TDR) instrumentation. The final recovery scheme, employing a controlled failure, involves recommendations on: (1) blasting techniques; (2) support systems; (3) mining sequences and scenarios; and (4) monitoring systems."

Jan 1, 1994

Today?s Topics ? Data to decision value chain ? Practical Considerations ? Example ? Before / After DSS ? Quick Decision Support Demo Practical Considerations ? More data is not necessarily better ? Organization and process silos ? Good vs. ?optimal?, but impractical Solutions

May 1, 2008

By Ertugrul Alp

Alp & Associates - Who We Are ?? Canadian consulting company (1999-?) ?? Principal Consultant: Dr. Ertugrul Alp, P.Eng. ?? Over twenty-five years experience serving the chemical, mining, pulp & paper, energy, steel, and transportation industries, and government clients. ?? Ph.D. in Mechanical Engineering, University of Waterloo ?? Experience: ?? Westinghouse Canada, Atomic Power Division, Manager, Analysis and Modelling ?? Concord Environmental (later Bovar Environmental), Principal, Manager, Air Quality and Risk Assessment ?? Arthur D. Little, Associate Director, Safety & Risk Practice Leader in Canada ?? Member: NATO CCMS Pilot Project on Disaster Preparedness (1991-1993) ?? Chair: MIACC Risk Assessment Expert Committee, 1995-1999 ?? Member: MIACC Committees on Land Use Planning and Pipelines (1993-1998) ?? Member: CSA/Q850 Risk Management Standard Technical Committee ?? Member: CSA/Z1002 OHS Risk Assessment Standard Technical Committee ?? Member: CCPA/CSChE Process Safety Management Committee (1999-?) ?? Member: ISO-31000 Risk Management Standard Canadian Advisory Committee ?? Chair: CSChE Process Safety Management Committee (2005-2006) ?? Chair: CSChE Expert Committee on Risk Assessment (1999-2005) ?? CSChE 2007 Process Safety Management Award

May 1, 2008

By Orlando C. Gaspar

The presence of ?ne-grained mineral intergrowths, the complex distribution of deleterious minor elements, and the variable base-metal contents in some assemblages commonly pose technical problems for the processing of volcanogenic massive sul?de ores. The bene?ciation of most massive sul?de ores from the Iberian Pyrite Belt requires extremely ?ne grinding to liberation sizes of K80= 15 µm to 25 µm. For several deposits, mapping of the ore types and metal zoning pat-terns has shown that the different ore types are distributed as ore lenses within the massive sul?des. Mineralogical, textural, and metallogenetic studies have provided an understanding of the distribution of both the vertical and the horizontal metal zonation in the orebodies. Because the ef?ciency of ore processing is affected by ore textures, and because the same mineral commonly has different textures and varies in chemical composition, a relationship between textures of the feed and the middlings must be established for all ore types de?ned at the deposit scale. Quantitative mineralogical methods have been developed to provide, on a timely basis, the information needed to optimize the concentration processes for the massive sul?de ores at the Aljustrel and Neves-Corvo deposits, Iberian Pyrite Belt, Portugal.

Jan 1, 1997

By H. Rozovsky

"AbstractThis paper discusses the methods of handling air in a large asbestos mill presently being completed at the Jeffrey mine of the Canadian Johns-Manville Company in Asbestos, Quebec.The mill, being the largest single asbestos producer in the world and capable of handling over 14,000 tons of ore per day, requires vast quantities of air. A minimum of 2,500.000 c.f.m. is required or about 10 tons of air for each ton of ore milled.Short descriptions of the process and systems requiring this air are given, followed by details of the fans and filters which make up the heart of the mill.This 'draw through' system, located on the top or 12th floor, is an automatically .controlled volume-pressure system creating the required suction to draw .air throughout the mill building and its numerous air systems.The dry mechanical method of milling develops enormous quantities of airborne dust and fibre. A section of this paper is devoted to a description of the multiplicity of dust systems within a system to control, filter, and remove this dust.Finally, the paper describes the method of returning the filtered air to the• working floors or to the outside, with some notes on heat, humidity and dust counts.IntroductionGeneralTHE discussions in this paper deal only with operations where air movement is involved. No attempt is made to delve into production methods.The Jeffrey mine of the Canadian Johns-Manville Company, located about 100 miles east of Montreal, is the largest single asbestos producer in the world, being responsible for over half of Canadian asbestos fibre production."

Jan 1, 1955