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By J. A. Cox, R. S. Mattson

"One of the main problems encountered in employing sublevel caving is the inherent high dilution factor. The operating results at Granduc illustrate that this dilution can be closely controlled and satisfactory recoveries achieved, in base metal ores grading less than 2.0% copper equivalent, by using an assay grade control system based on the fundamental draw characteristics. The history of draw control procedures employed since the start of operations provides an effective comparison between this system and one based mainly on tonnage. The transverse and longitudinal sublevel caving mining methods are described and it is shown how improvements in design layout, operating practice and draw control in narrow complex ore zones (12-foot minimum width) have raised the operating performance of the longitudinal system to a satisfactory level."

Jan 1, 1973

By M. Sahoo, P. Burke, Y. Fasoyinu, J. P. Thomson

The effects of grain refinement, mold temperature and chemical composition on the hot tearing resistance of aluminum alloys 535.0 and 206.0 has been studied by pouring constrained rod castings in metal molds. In addition, two prototype components that could be used in automotive applications were also poured from both alloys by gravity tilt-pour and low pressure permanent mold casting processes. This paper summarizes the results and issues encountered during the casting trials. It was shown that grain refinement and mold temperature ::::: 400°C reduced, and sometimes eliminated hot tear cracks in both alloys. The two prototype engineering components could be cast successfully from both alloys in metal molds. The metallurgical issues related to molten metal treatment and processing temperatures were well controlled. However, issues related to the control of hot tearing, casting and mold design must be addressed in future studies to guarantee the production of defect free castings.

Jan 1, 2006

By P. Rosario

"Current industry practice for HPGR assessment and sizing relies on conducting a series of tests using pilot-scale machines with roll diameters of 700 mm to 1000 mm. Substantial amounts of sample are required for such pilot test programs, typically 1 to 10 tonnes of the sample is needed depending on the level of study and complexity of the resource. Collection of large quantities of representative samples during the early stage development is challenging and expensive, thus significantly hinders the HPGR technology from being incorporated into early-stage designs. A robust and reliable laboratory test is therefore needed to allow a fair consideration of HPGR for early stage projects. With support from the Canadian Mineral Industry Research Organization (CAMIRO), the NBK Institute of Mining Engineering at the University of British Columbia (UBC) developed a suite of Piston Press bench-scale tests that correlated to pilot and full scale HPGR operating information (Davaanyam, 2015; Davaanyam et al, 2015; McClintock, 2018). The Piston Press Tests (PPTs) are capable of assessing the HPGR technology at the scoping, pre-economic analysis (PEA), and pre-feasibility (PFS) stages of project development. This paper will briefly describe the theory on which the PPTs are based, and then presents a case study conducted for a copper deposit to show how the PPTs are being used for scoping and pre-feasibility level studies. Specifically, the PPTs are being used to provide information for preliminary sizing and selection of an HPGR and to assess the effect of ore variability on HPGR performance. The results are also applied to developing HPGR circuit designs and can be incorporated in simulation so that optimum design parameters can be selected.INTRODUCTION It is widely accepted that high pressure grinding rolls (HPGRs) offer a viable energy-efficient solution for the modern comminution flowsheet design. Table 1 summarizes selected examples of HPGR applications in the hard rock mining industry. The main benefits of HPGRs are energy savings which leads to lower operating costs, and its stable operating characteristics that can better cope with variations in ore hardness when compared to the conventional SAG mill-based comminution circuits."

Jan 1, 2019

By V. Falmagne

The mining sequence at Noranda?s Bell-Allard mine calls for two mining fronts retreating toward a central pillar known as the Retreat Zone between pyramids A and C. It is clear from numerical modelling and rock mass characterization that the induced stress level in the pillar will exceed the rock mass capacity. A mining plan was developed including the re-dimensioning of stopes in the Retreat Zone, additional ground support and instrumentation in order to ensure the safety of the workforce and to maximize ore recovery while minimizing production delays. The mining strategy consists in allowing the rock mass to fracture and fail progressively while maintaining control of the existing openings with the appropriate support. A systematic analysis of rockbursting and caving hazards was conducted for all accesses and stopes in order to plan ground support and instrumentation needs.

Apr 1, 2004

By G. F. Round

In order to obtain values of angle of shearing resistance and initial resistance for McMurray oil sand for use in general design calculations, the shear strength of this oil sand was measured in a controlled strain type tester, modified so that the rate of deformation could be varied between 0.01725 and 0.1869 inches per minute. Effect of temperature was investigated by adapting the equipment to operate at both 71 ° and 185 °F. The data are reported in terms of angle of shearing resistance and initial resistance for varying rates of deformation, composition and temperature. While the main sets of results reported here were obtained at a bulk density range of 108.7- 109.5 lb. / cu. ft., some results were obtained at a bulk density range of 101-102 lb. / cu. ft. Analysis of varance tables have been drawn up from the results obtained from least squares correlations and significance tests applied. It was concluded that oil content and temperature were significant variables for the degree of shear strength developed by the oil sand; increase of oil content and decrease of temperature each cause an increase in shear strength. The bulk density range 108.7 to 109.5 lb./cu. ft. gave angles of shearing resistance from 30° to 40° and initial resistance values of 0.37 p.s.i. to 0.85 p.s.i. For the bulk density range 101 to 102 lb. / cu. ft., lower values of shear strength were obtained, indicating that compaction density was also of importance

Jan 1, 1960

By T. Xue

429 As part of Inco's S02 abatement project for its Sudbury operations, a weak acid treatment plant (W ATP) was commissioned at the Copper Cliff smelter in August of 2004 to treat the weak acid streams generated by the flash furnaces, the MK reactor and the fluidized bed roaster (FBR) gas cleaning plants. The W ATP process was developed by Inco Technical Services Limited (ITSL) by means of laboratory and mini-pilot plant programs. In the W ATP process, the feed solution containing arsenic, sulphur dioxide, iron and other impurities is treated by oxidation and neutralization to form a stable precipitate for disposal in Inco's tailings impoundment area. During the commissioning of the WATP, a team of operations, maintenance, engineering, project and R&D personnel was formed, and the designed capacity was achieved in less than a month. Since then, the W A TP has been operating smoothly and the impurities, specifically arsenic, in the Copper Cliff smelting process have been effectively removed.

Jan 1, 2006

By W. A. Padgham, J. A. Brophy

About 85 % of the 350 tonnes of gold produced by 25 mines in the onhwe t Territories (NWT) since 1935 has come from the Yellowknife-area mines, Con and Giant , which exploit shear zones in Archean mafic volcanic of the Slave Structural Province. Four percent of the total production has been from Archean iron formation-hosted depo its, mainly from Lupin Mine, which today produces more gold than Con and Giant combined and has been primarily responsible for the increase of WT gold output from 5 to 12 tonne per year since 1981. The remaining gold ha been won from the following deposit typesall but the last being in Archean rock : sedimentary-volcanic contact depo its uch a Discovery and Salmita (10 %); turbidite-hosted quartz-vein depo its uch a Camlaren and Ptarmigan (1%); Proterozoic deposits such as Shear Lake and Fox (1#) . All but I% of WT gold has come from the Archean Slave Structural Pro ince, which is also the premiere exploration area for gold deposit types that have yet to be productive in the NWT. These types include stratabound gold in mafic and in felsic volcanic rocks (eg. , at Indin Lake and Courageous Lake, respectively) as well as gold in plutonic rocks (eg. Anialik Gnei Complex). Deposits similar to those in the Slave have al o been found in the Archean Ennadai Belt of the Churchill Structural Province. In the Cordillera. there is potential for placer gold and for gold associated with Cretaceou intrusions.

Jan 1, 1986

By K. Sinding, R. Poulin

"Recent land-use decisions in British Colwnbia, and the publication of a report on compensation for expropriations of resource interests, have highlighted the nature of land use policies. Landuse decisions, such as the creation of large new parks, raise three principal issues which have implications for how land-use policy is conducted and how it impacts on the mining industry. The first is the identity of the parties advocating different land-use policies and their motives for doing so, the second is the changing nature of benefits derived from land, and the third is the change of property-rights regime which is devised to accommodate the (changing) benefits from using land and natural resources, as well as the interests of the different parties involved.Involved Parties and BenefitsThe process of establishing or modifying property rights depends on the interest groups involved. Three distinct categories, each with distinct incentives which can influence the process, must be distinguished: private claimants, politicians and bureaucrats (Libecap, 1989).The first groups claim rents and management powers through asset ownership. They may be incumbent owners seeking enforcement of the status quo, new claimants seeking redistribution of assets, or third parties who depend on the distribution of assets (e.g. lenders, labour suppliers and contractors). Some infonnal property arrangements can be negotiated within the group whereas others requires action in the political arena through lobbying politicians for (re)allocation of property rights and influencing bureaucrats for favourable administrative decisions. The second category is politicians, who direct the powers of the state to change or enforce property rights. Both incwnbents and office-seekers fall in this category and their actions and opinions are shaped by their constituencies and financial backers. However, not all causes can be championed and trade-offs have to be made, resulting in decisions that maximize political benefits. The third category of parties in the process is the bureaucrats. The power to manage has been delegated by politicians but bureaucrats also have opportunities and incentives to further their own interests. These can include maintaining or expanding jurisdictional turf or increasing operating budgets (Libecap, 1989)"

Jan 1, 1994

By L. B. Tsymbulov, L. Sh. Tsemekhman, A. N. Golov

Gipronickel Institute, JS is developing a process of continuous converting of Nicontaining copper matte and concentrates resulting in the production of blister copper and fluid NiO-containing slag in a two-zone Vaniukov furnace. The process under development is an alternative for the existing technology of blister copper production in converters, the latter being characterized with insufficient sulphur utilization, low direct copper recovery and the production of inconvenient for further processing solid slag on the basis of NiO and NiFe20 4- The results of pilot testing on processing of copper concentrate obtained from high-grade matte (HGM) separation in the two-zone Vaniukov furnace with the hearth area of 11.4 m2 are presented.

Jan 1, 2007

By J. E. Dutrizac

The dissolution of low-iron sphalerite, (Zn,Fe)S containing 0.08% Fe, in ferric sulphate-sulphuric acid media was investigated using closely sized fractions of crushed sphalerite crystals and sintered disks made from the crushed crystals. Linear kinetics are observed, and the predominant reaction products are ZnSO4, FeSO4 and elemental sulphur. The leaching rate increases systematically with increasing temperature, and the calculated apparent activation energy is 56 kJ/mol for the sized sphalerite and 54 kJ/mol for the sintered disks. The relatively high apparent activation energy suggests that the rate is chemically controlled, a conclusion supported by the insensitivity of the rate to the disk rotation speed. The rate increases as the 0.22 power of the Fe(SO4)1.5 concentration, and as the 0.22 power of the H2SO4 concentration. However, in the absence of ferric ions, the rate increases more significantly with increasing H2SO4 concentrations, and relatively rapid rates are observed in solutions containing >0.5 M H2SO4. In 0.1 M Fe(SO4)1.5-0.3 M H2SO4 media, the measured rate decreases with increasing sulphate concentrations, added as Li2SO4. The rate of dissolution of low-iron sphalerite is promoted by dissolved copper concentrations as high as 800 mg/L. In contrast, dissolved silver, even in the 0-2 mg/L concentration range, significantly retards the dissolution of the low-iron sphalerite.

Jan 1, 2008

By Azadeh Riahi

The main goal of this paper is to investigate the effects of permeability anisotropy in Large Open Pit (LOP) mines for problems that exhibit homogeneous anisotropic characteristics. The most important effect of the groundwater flow in open pit mines is on the stability of the pit slopes. This study will investigate the effects of having increased permeability in both horizontal and vertical directions on three aspects of LOP behavior, location of phreatic surface, pore pressure distribution and stability of slopes. The hydromechanical coupling is simulated using a one-way coupling approach. The Shear Strength Reduction method (SSR) is applied to assess the stability of slopes. The studies performed in this paper suggest that anisotropy in permeability leads to a significantly different regime of pore pressure dissipation depending on two aspects, ratio of anisotropy and the relative magnitude of permeability to simulated time. As a result, variation in safety factors and the location and depth of the failure surface must be expected.

Jun 1, 2012

By Michael Boyle, John Zeni

"The Blind shaft boring method is a mechanised process of excavating large diameter vertical shafts downward from the surface. It is a rotary drilling technique eliminating any requirement for personnel to enter the shaft or access underground workings during drilling and lining phases. Excavated material is delivered to surface carried by a flow of circulating fluid through the centre of drill rods. The drill assembly is suspended from a large A-frame rig and powerful winch at ground level providing vertical thrust to a hard rock cutter head. INTRODUCTION The Southern Coalfields Ventilation Shaft was constructed at a mine, 45 km north-west of Wollongong. The 5 m finished diameter (6.2 m drilled) shaft reaches a final drilled depth of 517 m, the deepest, fully lined blind bored vent shaft to date in Australia. Operated by a mining company in the Southern Coalfields, the expanding mine required a new ventilation shaft and associated surface infrastructure to service future operations. An assessment of future ventilation requirements for the coal seam operations identified a need to improve the capacity and reliability of the existing underground ventilation system in order to ensure a safe and efficient underground working environment. Installation of the new upcast ventilation shaft was determined to be the most cost effective and reliable solution to provide adequate ventilation for underground operations. The completed shaft is smooth and fully lined with steel/concrete composite liners that are hydrostatically sealed. The shaft lining is designed to meet the mine ventilation requirements for a service life of 20 years. The shaft intersects the top of the working section of the coal seam at approximately 513 m of depth. This includes the shaft collar depth and shaft bottom profiled intake section.PROJECT METHODOLOGY AND INDUSTRY BEST PRACTICE The shaft was drilled using the blind bore method, an innovative construction technique and an alternative to the traditional methods of sinking deep and large diameter shafts, such as raise boring and conventional drill and blast shaft sinking. The blind bore method allows the shaft to be drilled from the surface down without anyone having to enter the shaft or the mine during the construction process. This is by far the safest method of shaft construction and is especially suitable for difficult ground conditions where there may be unstable or water-charged strata. As this method involves drilling from the surface downward, shafts can be completed ahead of the underground mine development. Thus, allowing underground operations to focus on development and production without the conflicts of managing ventilation priority for underground contractors and mucking out spoil from excavation workings."

Jan 1, 2019

By J. W. Hohn

The precipitation of Fe(III) to form ferrihydrite in the presence of arsenic is the United States EPA's Best Demonstrated Available Technology for treating arsenic-containing hydrometallurgical solutions and waste streams. This technology has been widely adopted throughout the world and developments have been well reviewed. The adsorption and long-term stability of ferrihydrite can be improved by co-precipitating Fe(III) and Al(III) together to form an aluminum-modified ferrihydrite. Arsenate adsorption into ferrihydrite and modified ferrihydrite as a function of pH, Fe/As or (Al+Fe)/As mole ratio, and the initial As(V) concentration is presented and compared. The results of long-term aging of both adsorbents at 70°C for over a year are also summarized.

Jan 1, 2006

"5.1. IntroductionThe sample preparation requirements for bulk analyses of platinum-group elements (PGE) are different from the requirements for ore microscopy and in-situ analyses. It is necessary that the initial sample collection results in as representative a sample as possible for both types of analyses. Ingamells (1980) believes, however, that sampling is always imperfect and that there is no such thing as a truly representative sample. Once collected, the usual low content and irregularly dispersed nature of the PGE require that samples for bulk analyses be made as uniform as possible, whereas in samples for ore microscopy and in-situ analyses the PGE must be concentrated. Because of the generally high specific gravity of platinum-group minerals (PGM), certain precautions must be taken, such as mixing the sample material in the bags prior to opening.5.2. Preparation forBulk Analytical MethodsThe principal factors that determine the size of the sample required for a bulk analysis are grade, heterogeneity and grainsize. Initially, the grade and sample heterogeneity can only be estimated and a sampling methodology is developed with experience. It is essential at all times, however, that the assayers have information about the source of the sample and the purpose for the analysis. Information on the grain-size, which can only be obtained through mineralogical analysis, is also very important for PGE analyses, but, unfortunately, is often ignored.5.2.1. Samples fromUnconsolidated DepositsConcentrations of PGE may occur in eluvial deposits as well as in a large variety of alluvial deposits, including those of fluvial and glaciofluvial origin. These deposits are often difficult to map and sampling is further complicated by the wide range, from sand-size to boulders, of the non-POE-bearing constituents, and by the irregular distribution and shape of the ""pay streaks"". PGE concentrations in unconsolidated deposits are largely composed of resistant Pt-Fe and Os-Ir-Ru alloys (cf. Cabri and Harris, 1975 and Raicevic and Cabri, 1976), thus making comminution to the usual-150 to -200 mesh somewhat unreliable, due to the malleability of these alloys."

Jan 1, 1979

By V. Estrada, G. Aguilera

"Since the most of mineral processing are wet, and for more specific applications where it is necessary to increase the purity through leaching and / or concentration, the proper dispersion is the first, and perhaps more crucial stage in the whole chain of processing. This specific process is based on the formation of a dispersion or suspension of mineral, trying to make the mixture as homogeneous as possible, and with specific rheological conditions. Sometimes it is not enough agitation to make it happen, so that chemical additives are used as an aid. However, the addition of chemicals strongly alters the viscosity and other rheological properties of the suspension factor to consider for subsequent steps to ore beneficiation. In other hand, in a process where no chemicals used often employ large quantities of water to achieve dispersion. But if an efficient chemical agent, which optimizes said dispersion through a specific physicochemical effect on the particle surface is used, also it can generate rheological advantages, besides achieving rational use of water and increase the recoveries of the product main about also optimal costs. The aim of this work is to find the optimal rheological conditions for a dispersion of kaolin as study case, looking for stability, best disaggregation, viscosity and pseudoplasticity.To find the optimal additive, the evaluation parameters were: 1) Best degree of dispersion of the suspensions according to the analysis of the flow curve; 2) Best level of disaggregation of particle chemical analysis delaminated by Particle Size Distribution; and 3) Best thixotropic rheological parameters and pseudoplasticity. Finally the optimum additive as one that meets the best combination of parameters is proposed.INTRODUCTIONKaolin is a clay material formed by altering of feldspar composed mainly for kaolinite. Depending on the application, the kaolin as raw material must be refined and processed because the ores of clays contain usually a lot of impurities derived of its sedimentary source, such as feldspar, mica and quartz (Torres, et. al., 2011). According to the experience on the plant floor and the publication of several scientific papers, it is known that the dispersion is a crucial stage in mineral processing (Greene, Duke, & Hunter, 1965) (Raghavan, et. al., 2004), not only because of the disaggregation of particles, besides because of the humectation of them. Is clear that disaggregation of particles give to the suspensions rheological stability, and the humectation improves the effect of further processes like grinding or chemical treatment. The dispersion process involves making a suspension of the mineral with a solvent which is usually water, to obtain a homogeneous dispersion, with the aid of energy of stirring. Sometimes is not enough the agitation (even with high energy) for this to occur, so is necessary the use of dispersing substances which introduce ions and molecules as modifiers of chemical potential, forcing the molecules of the material to disperse. Sometimes their use even could affect the pH of the suspension in a non-desirable condition. (Flores, 2013)."

Jan 1, 2016

By F. R. Erick Mulder

"AbstractTwo bottom-hole samples have been taken from two new completions in the Turner Valley field, Royalite Lowery No. 8 on the west flank and Royalite No. 73, which was deepened into a lower fault block, on the northeast flank. From the bottom-hole oil of Royalite Lowary No. 8 a synthetic sample was prepared to simulate the original fluid in the reservoir, saturated at the gas-oil contact conditions. The sample from Royalite Lewery No. 8 has been shown to be the original fluid present at this well and represents the oil phase near the oil-water contact in• the reservoir. Complete chemical analysis, P.V.T., and viscosity data have been obtained on these reservoir fluids, which represent the range of saturation from the gas-oil to the oil-water contact in the Turner Valley oil structures. Sampling techniques and the application of the analytical data to reservoir conditions and field operations are discussed. Super-compressibility curves for an average separator tail gas have also been prepared. These data have not been available before. They will be of fundamental value in futu.re reservoir engineering studies of this field and will also serve as a guide in determining operating practices."

Jan 1, 1950

By V. I. Ryaboy, V. P. Kretov, I. V. Ryaboy, E. D. Shepeta

This paper studies the features of known and newly synthesized dialkyldithiophosphates and reagents with thioamide groups when separating copper-containing and arsenic-containing minerals in the flotation of skarn-scheelite-sulphide ore at the Primorskaya concentration plant. The optimization of dialkyldithiophosphate collectors was based on the study of their surface activity at the liquid-gas interface and estimated hydrophobic abilities. The flotation experiments show that the selectivity of action of the reagent increases with an increase of its surface activity and a reduction of hydrophobic ability when separating chalcopyrite and arsenopyrite. IMA-225-5 was proposed as a more efficient dialkyldithiophosphate collector, which increases the recovery of copper by 2.8% compared to the industrially used collector IMA-I413. Selection of the optimal structure for reagents with thioamide groups (derivatives of thionocarbamate and thiourea) was carried out according to their acidity and the presence of hydrophilic particles in their structure. Calculations were performed depending on the pH of the solution of chalcopyrite to determine the optimum reagent sorption and to further optimize the structures of these reagents. The tests with reagents with thioamide groups show an increase in copper recovery by 3-4% together with a significant increase of arsenic content compared to IMA-225-5. As a stronger collector with thioamide groups, it was recommended to use sample 234, which belongs to the thiourea derivatives. IMA-225-5 was recommended for industrial tests at the Primorskaya concentration plant. Thus, this study has shown that using dialkyldithiophosphate is more appropriate if it is necessary to increase the selectivity of separation of copper-containing and arsenic-containing minerals, and using reagents with thioamide groups, or their combinations with dialkyldithiophosphates, is more appropriate if it is necessary to increase the recovery of copper or the quality of copper concentrate with less selectivity of the process.

Jan 1, 2016

By Engineering Staff

"This paper briefly describes the surface mining operations at Smoky River Coal Limited (formerly McIntyre Mines Limited, Coal Division) near Grande Cache, Alberta. Geology, mining methods, equipment, manpower and reclamation and environment topics are discussed. Introduction Smoky River Coal Limited, a wholly-owned subsidiary of McIntyre Mines Limited of Calgary, Alberta, produces a high quality, low sulphur, low volatile bituminous coking coal from its minesite located at west central Alberta, approximately 20 km from the town of Grande Cache and 360 km west of Edmonton (Fig. I). Most of the coal property is contained within a 30 km long by 20 km wide block lying in a northwest-southeast direction in mountainous terrain. Elevations vary from 920 m above sea level ·at the plant·site on the Smoky River to 1,600 mat the upper levels of current and proposed mining operations. A total of 11 coal seams have been identified. Only two seams, No. 4 Seam and No. 10 Seam are currently considered of major commercial value. These seams are recovered by both surface and underground mining. Approximately 650Jo of the plant feed coal is obtained from a conventional shovel/truck surface mine; the balance is mined underground by room-andpillar methods. Background In 1921, McIntyre Mines Limited acquired some 26,300 hectares of coal leases at Smoky River. Since then the leases were explored intermittently by different companies including McIntyre. In the mid-l 960s exploration activities increased and several feasibility studies were completed. Development of the area was undertaken by McIntyre in 1968 and, in August of the same year, a long-term contract was signed with a consortium of Japanese steel mills for delivery of 2 x 106 t of clean coking coal for 15 years commencing in 1970. Production was focussed on underground mining, using longwall methods."

Jan 1, 1985

Energy benchmarking is widely applied across industries to determine the potential to improve energy performance. Unlike the many technologies for which energy benchmarks and efficiency rating systems are already in maturity, benchmarking of mining processes is still in its infancy. Benchmarking energy usage in mining operations, where energy costs are high and represent a significant portion of overall operating expenses, is challenging due to the uniqueness of each mining operation. Mines vary in terms of geology, geographic setting, ore body geometry, mineralogy which impact the mining method, material handling, processing and waste management. In order to gauge the opportunity for reducing the energy intensity of individual operations and also to compare the energy performance of operations on a global scale, the deployment of new benchmarking methodologies, models and frameworks is necessary. As a step towards the establishment of an accurate framework for benchmarking the energy consumption of mining operations, comminution, one of the more energy intensive mining sub-processes, was selected as the focus of a new energy benchmarking method. The methodologies and processes used to onset fragmentation in a rock mass to the crushing or grinding of rock to a size that is suitable for economic extraction are predominantly dependent on the ore properties. For this reason, site specific factors, such as the size reduction requirements and ore hardness were included in an energy benchmark model so that the energy performance of comminution processes at different operations could be normalized and compared on a global scale. Single particle compression breakage has been identified by several prominent researchers in the field of comminution as the upper limit of energy utilization in size reduction processes. For this reason single particle compression breakage was proposed as the basis of a work index for ores to be used as an input for the benchmark model. Overall, the new method showed that the energy benchmark for mineral comminution can be normalized and subsequently compared for a range of mining operations once the ore hardness has been appropriately characterized.

Aug 1, 2013

By J. Güntner

A significant portion of Outotec's business relates to the application of fluidized bed for processing a wide range of industrial materials, including gold ore and gold concentrate. As part of the former Lurgi and Boliden organization, our division constructed the first industrial reactor for roasting sulphur-bearing materials in 1950, based on the principles of fluidized bed technology. This process, when combined with efficient heat recovery and off-gas treatment and its conversion to sulphuric acid, became the standard for processing sulphur-bearing ores. In the last 60 years we have delivered more than 265 plants and developed (in addition to the standard fluidized bed solution) variants of the fluidization technology, such as the circulating fluidized bed and the bubbling fluidized bed. This paper describes the different options of the fluidized bed technology for gold roasting reflecting on main process design criteria.

Jan 1, 2011