Search Documents

By Edward (Ted) R. Lord

The application of thickened/paste tailings for surface disposal has been practiced for many years but has recently started to gain wider international acceptance. With tailings ponds coming under increasing environmental scrutiny, there is growing momentum towards mine/tailings plans that greatly reduce the size or even eliminate tailings ponds completely. This paper provides examples from the author's own experiences of the application of thickened/paste tailings for surface disposal in different countries, under different climatic conditions and in different industries. The paper will also comment on current research initiatives and future trends.

May 1, 2001

By Zhang Junzhi

This paper relates cross-border mergers and acquisitions (M&A) risk management theory to actual coal enterprises in China. The 3 phases of M&A are preparation, implementation and integration. By using the Analytic Hierarchy Process and fuzzy evaluation methods, we will try to establish a model to assess risks of the cross-border M&A of China?s coal enterprises. We then apply this model to the case of Yankuang Group acquisition of the Felix Company and receive the assessment results. There are significant reasons for quantitative research on risks of cross-border M&A of China?s coal enterprises, such as effective prevention and risk-aversion, and facilitation of cross-border M&As.

Aug 1, 2013

By D. C. R. Espinosa, P. Aliprandini, F. P. C. Silvas, J. A. S. Tenório, M. M. Jiménez Correa

"Nickel ores are divided into two types: sulfide deposits and lateritic deposits. About 60% of nickel resources are found in laterite ore, while the remaining 40% is contained in sulfide ore. Laterite ore is usually processed via pyrometallurgical means or through hydrometallurgical techniques that include acid leaching and metal value recovery from solution. In this study, copper and nickel adsorption by Dowex M4195 ion exchange resin from an acidic sulfate liquor was investigated. The acidic sulfate liquor was collected from an atmospheric leaching process (AL) of laterite ore. Ion exchange experiments were conducted in a batch system by varying parameters such as pH, time, metal concentration and temperature. Initially, mono-elemental synthetic solutions of nickel and copper were used in the experiments and then a synthetic solution simulating AL liquor was tested. Test results showed that the resin exhibited high selectivity towards copper and nickel, however, a high concentration of iron in the synthetic AL solution interfered with the recovery of nickel and cobalt by the resin.INTRODUCTION Nickel is one of the most important industrial metals in the world. It is widely used in industrial applications, such as the production of stainless steel, magnets, electroplating and special alloys (Dizge et al., 2009). The main sources of industrial nickel production are sulphide deposits; only 40% of industrial production uses lateritic ores. However, it is estimated that 60% of global nickel resources are found in nickel laterite deposits (Kuck, 2016). Since industrial nickel demand continues to grow, the development of new technologies for the extraction of nickel from laterite ores has become an interesting research topic (Agatzini-Leonardou, 2009)."

Jan 1, 2017

By Alex Matheson, Nick W. D. Massey, Peter T. Bobrowsky

Crowing pressures on aggregate resources include diminishing reserves, high transportation costs, sterilization and land use conflicts. In the absence of detailed resource knowledge for a particular region, aggregate resource potential maps provide the best "first approximation" regarding the surficial distribution of sand and gravel. The 1:50 000 scale Level Ill aggregate potential map integrates several important factors which influence the management of sand and gravel. Data used to generate this type of thematic map is readily available in most areas, fieldwork required is minimal, there is a logical quantitative evaluation of the data layers and integration is easily accomplished on a desktop PC-based platform. Also the aggregate potential map, with its focus on identifying areas of potential future aggregate exploitation as well as present inventory, provides a useful tool for the aggregate explorationist.

Jan 1, 2001

HIGH LAKE PROPERTY --HISTORYHISTORY -19501950??s ??Kennarctic Exploration discovers Exploration sulphides (A/B & (D Zones) at High Lake during helicopter reconnaissance exploration program.- -1991 93 Aber signs agreement to earn in to the High Lake Property from Kennecott. 63 holes drilled, primarily testing the known deposits. -2001 Wolfden purchases 100% interest in High Lake from Kennecott and Aber -2002 Wolfden performs helicopter borne TEM Survey over the High Lake Greenstone Belt. -2003 West Zone was discovered following UTEM & Gravity Surveys (performed by Teck Cominco ) over an airborne anomaly approx. 1km west of the known deposits. -2004 Wolfden awarded Bill Dennis Prospector of the Year

May 1, 2006

By Pritii Tam Wai Yin, Tony Leong, Neetu Bansal, James Vaughan, Amiel Boullemant

Mercury is a toxic element that is associated with many industrial activities including the Bayer process. Mercury is known to enter the Bayer process with the bauxite feed material and has the potential to accumulate as the process solution is recycled. This paper explores the speciation of mercury in Bayer process streams. The process parameters considered are the oxidising-reducing potential, basicity and temperature. The results of a refinery circuit survey are presented and compared with the thermodynamic predictions. Electrochemical measurements on relevant synthetic systems are also included.

Jan 1, 2014

By John E. Udd

"For decades, writers have expressed concern about impending shortages of professionals for Canada's minerals industry. Even under the present difficult economic circumstances, it is anticipated that the supply which will be available will not be adequate to meet the requirements in certain key areas including mining and petroleum engineering. It is evident that, unless further initiatives are taken, shortages will exist for some time.In this paper, the writer reviews information which relates to both the demand for, and the supply of, persons with advanced-level education in minerals-related disciplines. In particular, a summary is made of the information regarding supply which has been collected by the CIM General Committee on Education for many years.In concluding, the writer expresses some personal opinions regarding imbalances between demand and supply and offers some recommendations for future actions.IntroductionLast year, in a paper which was presented at the Annual General Meeting of the CIM in Calgary, the writer presented a review of the situation regarding professionally educated manpower for the minerals industry, and concluded that indications were that the gap between demand and supply was widening and that the situation could be expected to continue. Since that time, the deterioration of the nation's economy has caused an appreciable reduction in demand. Simultaneously, a further annual survey by the CIM has shown that the numbers graduating in certain specializations, notably geology and some of the technologies, are rising very rapidly. One of the great concerns of educators at present is that adequate opportunities may not exist for all of those who are now graduating.The danger of the present situation, then, is that a momentary lack of opportunities may cause potential students to choose alternative careers . Because of the lead-time which is involved, it is very possible that this could result in greater shortages during a period of economic recovery or expansion. Action must be taken to ensure that adequate numbers will be attracted to the industry, and this applies particularly to those who have already made the career decision and who are enrolled in minerals-related programs."

Jan 1, 1982

By K. Negishi, H. Izui, Y. Komiya

"Aluminum has the disadvantage of low strength. In order to obtain the high strength composites, crystals were refined in the composites. Grain refinement was approached at two process points, generating new grains and grain growth. It is important for refinement how to control the grain growth. Spark plasma sintering (SPS) technique and TiB2powder addition prevent grain growth. To investigate effects of strain and additives to the alloy, aluminum powder was sintered at 70 MPa and 80 MPa, changing the content of TiB2additive powder by SPS method. As the results, the crystal grain size was finer in the composite sintered at higher sintering pressure and with larger amount of additive, though over 1.0mass% TiB2addition dissuades grain refining. These grain refinements improve hardness and tensile strength of sintered aluminum alloys.INTRODUCTIONAluminum matrix composites have low density, high specific strength, and low cost. Their applications are growing continuously in the field of automotive and aerospace industries. Recent studies to improve their good mechanical and tribological properties use different ceramic materials such as Al2O3(Das, Munroe, & Bandyopadhyay, 1996; Ashwatha & Anthony Xaviorb, 2014),SiC(Hassani, Bagherpour, & Qods, 2014), B4C(Ehsan, Masoud, Touradj, Amir Hossein, & Ali, 2015),TiC(Ehsan, Ali, Masoud, Kamyar, & Touradj, 2017), and TiB2(Fei & Zhong-Hua, 2013).On the other hand, grain refinement is also an important techniques for improving the properties of aluminum alloys. Finer grains improve the mechanical properties of the alloy. For cast and wrought alloys, addition of grain refiners in molten alloys accelerates generation of nucleus and suppresses grain growth. Al-Ti-B alloy is generally added as grain refiners in the molten aluminum alloys(Easton & Stjohn, 2001). Especially, TiB2has very high melting point, low density, and excellent hardness. Therefore, TiB2was selected as additions into aluminum alloys. Liquids reaction leads to high cost, oxidation, discoloration of molten alloy, and clustering of additive powder as compared with solid reaction such as sintering. However, sintering of aluminum alloy powder with ceramic powders is difficult for oxide layer surface. Recently, we take attention to spark plasma sintering (SPS) as advanced sintering process. SPS process can easily sinter a high quality specimen at a lower sintering temperature and in a shorter time than conventional sintering processes. By SPS process, we have sintered titanium powders that are as difficult to be sintered by any other processes as aluminum powders, and improved mechanical properties by adding hard ceramic powders TiC and TiB(Kamegawa, Izui, Komiya, Kobayashi, & Arimoto, 2015; Sampei, Izui, Komiya, Shigimura, & Suzuki, 2015). Furthermore, it is important to consider not only pure aluminum but alloys for solid-solution or precipitation strengthening. Actually, pure Al does not have enough strength compared with the alloys. Al-Cu alloy and Al-Mg alloy demonstrate adequate strength for industrial and commercial sectors. Al-Mg alloy retains good formability, and has high resistance to corrosion. It is therefore used for many applications. We must consider alloying processes. The most cost effective process is blended elemental technology where alloying elements are added to base powder as elemental or master alloy powder (Smugeresky & Dawson, 1981; Yasue, Radjai, Miwa, & Sakaguchi, 2003; Bolzoni, Esteban, Ruiz-Navas, & Gordo, 2012)."

Jan 1, 2018

By A. Moyano

The development of the traditional converting process performed in a PeirceSmith or Hoboken converter is limited by the investment magnitude associated to the fulfillment of the environmental regulations. Thus, the continuous converting process rather than a conceptual process alternative is becoming a necessity for a smelter facing limited converting capacity and/or lacking of fulfillment of the environmental regulation with its maximum converting capacity. The objective of this paper is to present the progress of the Codelco continuous converting process evaluated at pilot-scale level when converting solid mattes or white metal into blister copper. These tests allowed for gathering of relevant data to be considered for a new stage of evaluating the Codelco continuous converting at industrial-scale test. The pilot-scale tests were done in a Teniente Converter pilot scale unit at the Codelco Norte Smelter. The results of processing solid copper mattes (65-75% Cu) and producing low sulfur content blister copper with production of a constant S02 gas concentration, and the production of liquid slag with low copper solubility was achieved and is discussed in the present paper.

Jan 1, 2007

By W. E. Newton

THE following notes are offered primarily to show that industrial minerals or their products have a much more important place in the metallurgical industry than is perhaps generally realized, and with the hope also that some statement by the metallurgical consumer of the relative merits of various materials for particular requirements or services will l;>e of value to the industrial mineral producer. These notes are not in any way presented as complete. Also, some of the statements made may be debatable. The grouping adopted is as follows: (1) Refractories; (2) Fluxes; (3) Construction materials; and ( 4) Miscellaneous applications. Fuels are not dealt with in the present paper. REFRACTORIES GENERAL: Refractories are materials which will withstand high temperatures with-out melting or becoming markedly soft or pasty. While their primary function is to withstand heat, they are usually called upon to resist one or more of the following destructive influences: abrasion, pressure, corrosion by slags or fluxes, and rapid changes in temperature. Refractory materials may be conveniently divided into three classes: (1) Acid refractories-consisting of silica, or containing silica as their chief constituent. They combine more or less readily with metallic oxides, forming silicates, and are hence termed 'acid'. The most important of these are quartz, quartzite, siliceous sand, tripoli, Dinas rock, and ganister. Most fire-clays, although generally considered neutral sub-stances, contain relatively small amounts of free silica and are, to that extent, acid. (2) Neutral refractories-the term is merely relative in most cases, since, at high temperature, many of the refractories that are classed as neutral will react chemically with a strong base, functioning as a weak acid; or, conversely, with a strong acid, functioning as a weak base. Chrome and graphite are the most nearly neutral of all the commonly used refractory materials.

Jan 1, 1936

By S. L. Chen

The Kumera Technology Center developed a unique type of steam dryer for drying copper concentrate in the mid 1990s. The dryer has been chosen in several copper smelter projects since 1999. To expand production capacities, the Norddeutsche Affinerie smelter, the Pirdop smelter of Cumerio, the Toyo smelter of Sumitomo Metal Mining and the Tamano smelter of Hibi Kyodo Smelting have carried out projects in which Kumera Steam Dryers were installed. The capacity of a single steam dryer varies from 70 t/h to 160 t/h. This article summarizes the latest operation results of the Kumera Steam Dryers in these smelters and introduces the progress of the ongoing projects in Yanggu Xiangguang Copper, Guixi smelter of Jiangxi Copper, Jinlong Copper, Boliden Harjavalta, and Onsan smelter of LS-Nikko Copper.

Jan 1, 2007

By R. O. Suzuki, S. Natsui, R. Nashimoto, T. Kumagai, T. Kikuchi, H. Takai

A newly developed computational fluid dynamics model based on a multi-phase particle simulation is presented for predicting the entrainment behavior of liquid metal into slag due to rising single bubble. By comparing results calculated using this model against experimental data, it was found that the transient behavior of bubbles and the two immiscible liquids can be accurately estimated by this method. The rupturing of the thin water film surrounding the bubble was less reliably predicted, but this 3-dimensional unsteady numerical model still nevertheless provides valuable new information for directly predicting the change in the liquid-liquid interface over time. This model predicted the Young-Laplace pressure, and the interface shape was simulated with volume conservation using this model as opposed to the conventional particle method. This simulation model can calculate both of dispersed phase and continuous phase seamlessly.

Jan 1, 2015

By Megan Becker, Aubrey Mainza, Indigo Research Laboratories, Jenny Wiese, Gaynor Yorath, Lucy Little

Particle shape characterisation has an important role to play in mineral processing, to clarify effects of shape on rheology, equipment wear rates, comminution, classification, sizing and flotation. However in industry, shape characterisation is not routine, and the most commonly used shape descriptor in the field (circularity/ angularity/ sphericity) is not invariant. This study aims to investigate shape measurements for a fine particulate ore sample measured with different analytical devices. Two Automated Scanning Electron Microscopy devices with Energy Dispersive X-ray Spectrometry (FEI QEMSCAN® and Zeiss Mineralogic®), and a camera based image-sizer using dynamic image analysis (Retsch CAMSIZER® XT) were compared. Each device was used to analyse the shape characteristics of specific particles in both a coarse sample (–212/+150 µm) and a fine sample (-53 µm) of UG2 platinum ore. Circularity and Roundness frequency distributions obtained from the three devices were then compared. For selected individual particles, circularity showed higher variability than roundness, and the sample circularity distributions obtained by the three devices were completely different. It is clear that circularity data from different studies relying on different devices should not be compared on an absolute scale. The shape parameter roundness was found to be a more robust descriptor than circularity, and it can give a stronger indication of a particulate sample’s shape characteristics on an absolute scale. However, there were still significant differences in the roundness measurements obtained by the CAMSIZER XT and the two Auto-SEM devices, which was attributed to the dissimilar mechanisms of image capture.

Jan 1, 2016

Building block cave operations involves significant commitments to capital and time before arriving at completion or full scale production. The focus of the mine planners is habitually to minimize the upfront capital and achieve target development rates and construction dates. However, management of the construction of block cave projects requires understanding of the strategic/tactical decisions that the project planners can take to increase the value of the project and cope with schedule risks. As block cave projects involve development of vertical and lateral access to the underground footprint and ore body, more attention to uncertainties is required as most of those projects need to confront delays leading to a decrease in value. The standard process of development and construction scheduling is often not planned with provisions to realise uncertainties in the construction phase. Uncertainties and risks such as poor ground conditions and equipment breakdowns are the primary reasons for schedule slippage. As a result most of these projects experience delays. In order to mitigate risk to the project schedule, we centre our attention on increasing the value of the project by spending more money upfront and improving the schedule rather than focus on minimizing the upfront capital. Scenario-based simulations along with project appraisal methods hold great promise to address those challenges and enable mine planners to make better decision and enhancing project value. This paper will present a hybrid simulation based approach to model the process of development and construction based on discrete event (DES) and continuous based simulations (CBS). Such simulations will be conducted for scheduling multiple development headings (Apex, undercut, extraction, and haulage levels). Two scenarios are utilized to investigate the impact of risks on schedule and how flexibility in construction can be incorporated to minimize delays: (1) The bench mark scenario is created based on actual data from an existing case study. (2) The flexible scenario is an alternative way to use primary production infrastructure (Ore Handling System) including conveyer drifts, conveyer belt, and a gyratory crusher in the construction process and that requires the system to be in place before starting lateral development in the footprint. As a result, a truck-load system versus a conveying system will be studied to observe the gain in construction speed and to estimate the premium cost for mucking rock from headings and drawbells and transporting it to surface. Such strategic flexibility would be part of the original budget to make the tactical flexibility available during construction. Continuous cash flow models are used to evaluate and compare the scenarios. This study is an example of how new techniques in planning can be used to support decision-making processes in block cave design.

Aug 1, 2013

By Marc-André Villiard, C. St-Onge, V. Silla, J-C Milot

Rio Tinto Fer et Titane (RTFT) operates a metallurgical complex in Sorel-Tracey, Canada. In the Ore Preparation Plant (OPP), ilmenite ore is roasted through four parallel rotary kilns generating 95% of the plant wide sulphur dioxide (SO2) emissions. RTFT proactively set an annual emission cap for SO2 to be achieved by 2015. To achieve this targeted SO2 reductions, a technology evaluation and selection exercise was carried out, followed by detailed engineering and implementation. After a detailed evaluation of SO2 scrubbing technologies, the Circulating Dry Scrubber (CDS) system was selected as the most appropriate desulphurization system for this application. The system was implemented and commissioned from 2013 to 2015. General performance testing conducted in May 2015 demonstrated that the system achieved and surpassed the anticipated design values in terms of SO2 removal efficiency and hydrated lime utilisation. This paper summarizes the SO2 technology selection process, design features of the selected technology, project implementation and final performance testing of the SO2 abatement system.

Jan 1, 2015

By D. Mraz

"Under high pressure in a deep potash mine, the salt rock behaves in accordance with the concept of a generalized, perfectly plastic substance. The paper presents the evidence of this behaviour and engineering concepts f or room-and-pillar design. IntroductionThe mining and refining facilities at International Minerals &. Chemical Corporation (Canada) Limited are located near Esterhaz y at the southeastern edge of the Saskatchewan evaporites. Ore extraction began in 1962 and at the present time the annual mining capacity is in excess of eleven million tons of potash ore.A generalized geological section is shown in Figure I. The mining horizon is overlay in by 100 feet of rock salt followed by a thin bed of competent dry shale. The strata in the next 1,500 feet are generally competent and locally water bearing. The Blairmore formation contains strata of water-bearing unconsolidated sand. Below the mining horizon, rock salt is interbedded with anhydrite bands.The 8-foot mining bed is distinguished mainly by grade and clay content, as there is no definite bed boundary. The chief mineral s are halite, sylvite and, in some cases, carnallite, with up to 2 per cent disseminated clay. The ore is coarse grained, with crystals averaging one-half to three-quarters inch across.The major mining problem is related to the fact that the Dawson Bay formation, overlying the evaporites, contains areas and channels that are highly porous and permeable and are filled with unsaturated brine under high pressure. Consequently, all mining areas, with no exception, must be so designed that the overburden salt stratum remain s competently supported for the duration of the mine .This paper outlines a successful engineering method of determining the stability of the pillar s and designing a stable room -and-pillar mining system."

Jan 1, 1980

By K. P. Wright

THREE OF the gold mines in the Red Lake Camp operates fluid bed roasters in their milling circuits. The mines are Campbell Red Lake, Cochenour Willans, and Dickenson. The roasters are used for the autogenous roasting of a flotation concentrate for subsequent gold recovery by cyanidation. Cochenour and Dickenson operate single stage reactors, whilst Campbell use a two-stage system. Ore treated by the mines is similar in that the major part of the gold is associated with arsenopyrite. Other sulphides present are pyrite, pyrrhotite, stibnite and sphalerite. Gangue minerals are mainly quartz, with carbonates and talc. Mineralization is, for the most part, extremely fine, and there is intimate association between sulphides and quartz, so much so, th at a picked specimen of apparently massive arsenopyrite will frequently contain as much as 80 per cent gangue. Gold recovery by straight cyanidation on this type of ore would not be higher than 80 per cent and

Jan 1, 1961

By J. D. Bosman, L. J. Gardner

"The Bushveld Complex is a large layered igneous intrusion, located in the northern parts of the Republic of South Africa. The complex hosts the largest known reserves of Platinum Group Metals in the world. On the western limb of the complex, mining of the Merensky economic horizon and UG2 chromitite layer has been conducted for many years by several mining companies, including Impala Platinum Limited. Over the past decade, Impala has planned a new generation of greenfield vertical shafts, commencing with comprehensive geological and geotechnical studies. As part of the geotechnical studies, numerous tests have been conducted to quantify the mechanical properties of the various near-reef rock types. These tests include point load tests conducted in the field, as well as uni-axial compressive strength, triaxial compressive strength, and Brazilian disc tensile strength tests conducted in specialist laboratories. The authors have compiled an extensive database containing a large number of tests for different rock types, ranging from felsic Anorthosite to mafic Pegmatoid. The database was analysed to quantify the mechanical properties and values for Mohr Coulomb and Hoek Brown failure criteria for each rock type typically exposed by mining. The paper will provide a data set of rock mechanical properties typically used in numerical modelling and other design processes. Using the significant number of tests available, data describing the variability of the various parameters will be included."

Jan 1, 2015

By Cris Sideco

This paper describes the concentration processes of the Sullivan. Concentrator, including crushing , transportation, sink-float, grinding , flotation and dewatering. Handling of hot muck has had a deleterious effect on most of the processes, resulting in significant operating problems and poorer metallurgy. These problems are described -in detail. THE SULLIVAN CONCENTRATOR is situated in Kimberley, high up in the Purcell Range of the Selkirk Mountains, at an elevation of 3,600 feet, approximately 4 miles from the Sullivan Mine (see Fig. 1). The original plant went on stream on August 23, 1923 at a designed capacity of 2,500 tons per day. This has been increased in stages to its present rated capacity of 11,000 tons per day. The latest stage was in 1949, when several major projects, including the underground crushing plant, the sink-float plant and the installation of a rod mill, were completed. Some 112,800,000 tons of ore have been treated in this concentrator to November 1975. The plant started on a 48-hour/ week schedule, but was reduced to 44 hours/week in October 1946 and down to 40 hours/week by the end of 1949. Except for a 6-month period in 1952 when the mill operated continuously, the 40-hour/week, Monday to Friday schedule was in effect.

Jan 1, 1977

By Y. Kusuda

Since 1981, the Annaka refinery has recovered zinc from zinc leach residues by the Waelz Process. The important considerations of this process are the prevention of the growth of coating accretions in the Waelz kiln and the improvement of the zinc volatilization rate. In this paper, simulation predictions and the results of the industrial operation regarding the prevention of coating accretions in the Waelz kiln and the improvement of the zinc volatilization rate at the Annaka refinery are reported and compared.

Jan 1, 2006