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By Pierre Bernard

Contents of the presentation ? Overview of Brunswick 12 Mine ? Brief description of the mine geology ? Summary of the current Mineral Reserves and Additional Mineral Resources ? Review of the ongoing mining remnants evaluation process, particularly emphasizing the integrated work between the mine geologists, the mine engineers and the metallurgists ? Challenges and opportunities to extend the mine life

Apr 1, 2005

By J. Bednar, R. R. Rogers, W. Dingley

"Zinc is by far the most important metal used for protecting steel from the ravages of corrosion, and cadmium is also used extensively for this purpose. These metals are applied by electrodeposition in cyanide baths when a particularly good appearance and high throwing power are required. One great disadvantage in using these baths has been the decrease in cyanide concentration and the increase in carbonate concentration that takes place during the plating. Another disadvantage has been the development of serious embrittlement in high-strength steels. The present authors have developed new cyanide baths for electroplating both zinc and cadmium on steel. These baths are stable in composition during plating, they have not produced appreciable embrittlement in the high-strength steels that have been investigated up to the present time, and they permit the use of considerably higher plating current densities. In addition, they produce extremely fine grained coatings that are attractive and have excellent adherence and covering properties. Brighteners can be used in the plating baths if bright finishes are required."

Jan 1, 1967

By Wynne Potter

"On the west coast of Cape Breton Island four coal basins have been identified, varying in age and extending from Port Hood northeasterly to Chimney Corner. Those of Chimney Corner - St. Rose in the north and Port Hood in the south belong to the Pennsylvanian Riversdale Group while lying between them are the coal basins of Mabou and Inverness belonging to the younger Pictou Group. Almost all of the coal basins are submarine and coal mining was carried out on all basins at various times. The seams in all basins dip steeply seaward at angles from 10 to 20 degrees but were found to flatten seaward. The coal is ranked as a high volatile C bituminous coal. Ash and sulphur contents are high compared with Sydney coal and the coal has a tendency to spontaneous combustion when stored in large quantities.Of the four basins, the most significant is that of Mabou. At Mabou recent seismic and drilling investigations have indicated that although a sizable reserve of coal may be found offshore the structural problems, particularly faults, and the poor quality of the coal encountered will make it a resource of the future, if at all. Inferred resources have been calculated at 150 million tonnes in four seams over a 10 km2 area and extending 3 km from shore. The quality of the Mabou coals varies with ash, ranging from 5 to 25 per cent and sulphur up to 6 per cent. Calorific value ranges from 25.3 Mj I kg to 31. 7 Mj I kg. The Port Hood and St. Rose -Chimney Corner fields (Fig. 1) contain 16 million and 3 million tonnes respectively, but the Inverness basin is considered to have been depleted. The active mine in this area is the Evans Mine at St. Rose that is currently producing between 30 -50,000 tonnes a year from proven reserves of approximately 3 million tonnes."

Jan 1, 1985

By M. P. Rennick, D. M. Burton

Abstract -The Murray Brook massive sulfide deposit, which was the first geochemical discovery in the Bathurst camp, is one of the largest sulfide deposits in the area. The massive sulfides are hosted by quartzose metasedimentary rocks in the lower part of the Ordovician Tetagouche Group. This thick succession of sedimentary rocks is overlain conformably by felsic volcanic rocks, and is structurally overlain by mafic volcanic rocks. The massive-sulfide body is polydeformed, but primary metal zoning is still discernable and may permit future exploitation of discrete lead-zinc and copper zones. Although it was discovered in 1956, the deposit was not developed unti11989, when Murray Brook Resources commenced processing of gossan containing precious metals. Recovery of gold, silver, and mercury is accomplished by indoor vat leaching on a year-round basis.

Jan 1, 1992

By Roland Hunt

This paper deals with the practical problems as sociated with blasting a heated pillar remnant. This pillar remnant was the final stage in the blasting of a multi-stag e pillar blast. Production from the previous stages had produced burning sulphide ore, resulting in high rock temperatures in the final unblasted stage. This is an account of how, under difficult conditions, the pillar remnant was blasted.

Jan 1, 1977

By T. Miura, Y. Mori, H. Aoki

In a flash smelting furnace, easily combustible concentrate particles excessively oxidized and melt. The excessively oxidized molten particles then collide with less oxidized solid ones to create uniform oxidized molten particles. This collision phenomenon plays a very important role in achieving high smelting performance. The authors developed a mathematical model describing above combustion phenomena. This model incorporated fluid flow, heat and mass transfer, chemical reactions and collisions of concentrate particles. Both gas flow and particle motion were calculated using the Eulerian method. Copper concentrate was assumed to consist of chalcopyrite(CuFeS2). Considered in the concentrate reactions were the decomposition of CuFeS2, and the oxidation of the resulting sulfur(S) and pyrrhotite(FeS) to produce magnetite(Fe30 4) and sulfur dioxide(S02). Moreover a reaction due to concentrate particle collisions, in which Fe304 in the excessively oxidized molten particle reacts with FeS in the less oxidized particle, was also considered. The particle collisions were assumed to occur according to a collision probability rule obtained by computational experiments. Particle growth in diameter was described as a change in the volume fractions of particle phases. When applied to a commercial flash smelting furnace, this model reproduced the particle growth and component transfer as observed in the actual furnace.

Jan 1, 2007

By M. Takebayashi, M. Shingu, H. Nagai, T. Nakai, S. Asano

The Toyo Smelter and Refinery, owned by Sumitomo Metal Mining Co., Ltd. (SMM) is located in the coastal zone of Saijo City and Niihama City, Ehime Prefecture, Japan. The refinery has been producing copper, sulfuric acid, and precious metals such as gold, silver, and PGMs. Previously, the process of precious metals recovery was a combination of pyrometallurgy and an electro-refining process with the conventional cupellation for around 400 years. However, this process had some major problems such as non-efficient recovery of valuable metals, high environmental risk by pyrometallurgy, high cost for maintenance of equipment and so on. In order to solve these problems, a thorough hydrometallurgical process for precious metals refining using chlorine leaching technology was originated and developed by Sumitomo and thereafter commercialized in 2004 at Toyo Copper Smelter and Refinery. This new process enabled shorter-term recovery of gold and manpower saving, and occupational safety and working conditions have also been improved. Superiority over the existing hydrometallurgical processes was also confirmed, for example by the achievement of 99.99% pure silver production without an electro-refining process. This paper summarizes the hydrometallurgical technologies for precious metals recovery such as chlorine leaching of copper anode slime for silver recovery, solvent extraction (SX) for gold recovery, and ion exchange (IX) for PGMs recovery. It also presents a unique silver purification process. INTRODUCTION Sumitomo Metal Mining Co., Ltd. (SMM) produces copper, precious metals and rare metals as by-products at the Toyo Copper Smelter and Refinery, and nickel and cobalt at the Niihama Nickel Refinery. Precious metals contained in nickel ore are also separated and refined at the Toyo Refinery after concentration. SMM has been refining precious metals using the pyrometallurgical method. In recent years, we have revamped the separation and refining process of precious metals dramatically by making use of advanced hydrometallurgical and engineering technology developed in the company. In this paper, we introduce the history of development and techniques of this process, and also introduce in detail the technologies of gold refining, PGMs recovery, selenium recovery, and silver refining which have been particularly difficult to achieve.

Jan 1, 2019

By P Kovacs, D. L. Flock

For the purpose of reservoir-performance calculations a balance can be made between the materials with-in the reservoir and the production from the reservoir. The material balance equation, a relationship which holds under or near equilibrium conditions, has been used in many forms by the Petroleum Engineer for the determination of initial oil-in-place in the reservoir and the calculation of performance into the future. One of the more recent methods developed by Tracy, utilizes a modified form of the Schilthuis material balance. In the latter case, values of incremental production are assumed for a particular pressure drop, a value of the gas-oil ratio found and a check of this estimate made by calculation"' the initial oil-in-place. Tracy's method utilizes an estimation of the instantaneous gas-oil ratio and by trial and error a value of the gas-oil ratio is

Jan 1, 1961

By D. Farrish, W. A. Grell

"IntroductionMost base metal mines sell their concentrate to a custom smelter. The two parties concerned therefore draw up a contract which would detail the conditions under which concentrate sales will take place. The contract will identify treatment and marketing charges (including escalations), deductions for metal losses in the smelter, pricing formula, timing of payments, penalties for deleterious elements, etc.An understanding of the smelter contract is important to the mineral processor, for it will determine how he operates the plant to maximize economic return.Description of Contract ClausesUsing copper concentrate as an example, the smelter contract generally contains the following three basic charges:I. Metal Deductions- as the smelting process does not recover all the metal contained;2. A Smelting Charge- expressed per ton of material to cover costs on the bulk material such as receiving, unloading, thawing in winter, sampling, roasting to drive off sulphur, smelting through the matte and blister stages to recover mostof the copper and precious metals;3. A Refining Charge- expressed per pound of copper.The following is a review in some detail of a number of clauses which could be considered typical of a treatment and marketing type of copper concentrate sales contract. Most normal considerations in an agreement could be covered by the following types of clauses.Terminology- covers definitions, units of measurement to be used (e.g. short tons, troy ounces, etc.), currency (Canadian dollars). The term ""unit"" may be defined - l OJo of a ton of concentrate, e.g. one unit of copper means 20 pounds of copper per short ton of concentrate."

Jan 1, 1989

By Robert B. Parsons

"A t last the legal red tape which has tied up flow-through share financing has been cut. New rules effective for deals signed after 1986 simplify flow-through financing by removing the necessity f or cumbersome agency relationships. But there is no free lunch-the new rules require increased government reporting. And beware federal tax reform promises to have a good look at the new flow-through share rules. IntroductionFlow-through shares have always worked better in theory then reality as an effective financing tool. The concept is straightforward: a transfer of risks, tax deductions, and potential returns. But the mechanics of the old flow-through rules made the transfer of risk impractical to impossible by placing the responsibility for incurring Canadian exploration expense (CEE) on investors. The new rules are significantly more realistic, shifting that responsibility to the issuing corporation. However, every silver lining must have a few clouds around it. In the case of the new flow-through rules, the more obvious negatives are increased reporting requirements and reductions in CEE eligible for flow-through by amounts of assistance received. The new rules are effective for deals signed after 1986, however, so a few old-style deals are still around. Practical Difficulties with Old RulesThe old rules which applied to investments in flow-through shares were structured so as to make it the responsibility of the investor, rather than the issuing corporation, to perform the Canadian exploration expense for flow-through. Since most investors had neither the expertise nor the inclination to incur the CEE, this requirement necessitated the use of cumbersome arrangements whereby the investors would appoint an agent (usually the issuing corporation) to incur CEE on their behalf. Although the issuing corporation might consequently be the party which actually spends the flow-through share funds on CEE, the awkward legal structure of such an arrangement made the investor the ""principal"" incurring the CEE. As such, the requirements of the old rules were met and the investors could receive their flow-through share s."

Jan 1, 1987

By Shinji Shirakawa

The gold wire bonding technology is widely used for electrically connecting aluminum pads on IC devices to external terminal of semiconductor. In 1960?s, the tensile strength of gold bonding wire was about 100 MPa only. However, recently the wire with 300 MPa in strength has been developed. Since the gold bonding wire was started to use for IC package in early 1960?, the many types of gold bonding wire has been developing continuously in order to meet market?s needs, such as high density, small size and thin type of IC packages. Moreover, electronic equipments were used in automobile applications and also demanded good reliability under severe temperature environment. Thus Au-Pd alloy wire has been introduced instead of the wire with 4N(99.99wt%) purity gold to provide excellent reliability in Au-Al bond interface. The phenomena at Au-Al interface in the high temperature storage have been already explained by several studies as follows. There are five phases of inter metallic compound (IMC) between gold and aluminum. Just after bond gold ball on aluminum pad, Au5Al2 phase was formed and occupied almost all of IMC area. During high temperature storage test, Au5Al2 phase transformed to Au4Al phase, then this phase was corroded by Bromide (Br) ion that was isolated from molding resin. Thus the reliability between Au and Al degraded. In case of Au-Pd alloy wire, the concentrated palladium phase (Au-Pd-Al) was formed at the interface between Au alloy ball and Al pad. The Au-Pd-Al phase prevented from transforming between Au and Al, therefore Au5Al2 phase was hard to transform to Au4Al phase. Consequently the reliability at the interface between Au alloy ball and Al pad was less degradation. However, in recent study using several advanced analysis technique, Au4Al phase was found at the interface between Au alloy ball and Al pad same as the case of conventional gold wire (4N purity gold bonding wire). It was suggested that the formation of concentrated palladium phase (Au-Pd-Al) related the excellent reliability at ball bonding process.

Oct 1, 2003

By Michael K. Watkeys, Jacobus E. Potgieter, E. Guy Charlesworth, Carl R. Anhaeusser, Roger L. Gibson, Alexander F. M. Kisters

Intrusive features of cupriferous noritoids from the deeply eroded Proterozoic granite-gneiss terrane of the Okiep Copper District in South Africa illustrate the emplacement of basic magmas into a mid- to lower-erustal environment. The small, easterly trending intermediate to basic intrusions of the so-called Koperberg Suite display a wide variety of geometries, occurrence and emplacement modes, including dike-, sill- and plug-like bodies. Coeval granulite-facies metamorphism, partial melting and ductile deformation of country rock gneisses during intrusion of the basic magmas led to emplacement and dilation processes of the intrusions which differ significantly from those described for dikes and sills at shallow crustal levels. Regional tectonic stresses are largely negligible due to very low differential stress [( )] during deformation and intrusion, which permits emplacement at high angles to the principal compressive stress and which follows favorably inclined structural anisotropies. Dilation of the basic intrusions is largely determined by compositional differences of host rocks and occurs by thermal erosion, i.e., assimilation of wall rock gneisses. Low length-to-width ratios of basic to ultrabasic dikes and predominantly diapir-like outlines of mesocratic bodies are indicative of low viscosity contrasts between the mafic magmas and high-grade metamorphic host-rock gneisses. Buoyancy-controlled ascent of the basic to intermediate intrusions is expressed by a broad compositional zoning of basic bodies with respect to the granite-gneiss stratigraphy. Various intrusion modes within the stratigraphic column of the granite-gneiss sequence reflect a lithological and structural stratification of the seemingly homogeneous granite-gneiss terrane.

Jan 1, 1994

By Jean-Pierre Birat, François Hanrot, Gérard Danloy

Global warming presents an enormous challenge to the steel industry, which is both carbon-intensive and energy efficient. Lean production can provide some short-term emission mitigation, at the level of the Kyoto requirements. In the middle term, more use of scrap will also help alleviate emissions. But to reach much larger reductions in GHG emissions, on a par with the likely targets that will be set after the Kyoto period, the steel industry will have to imagine new production paradigms, which constitutes its most formidable challenge for the years to come. Carbon capture and sequestration, processes leaner in carbon use, electricity and hydrogen from green sources will have to be added together in a patchwork of process routes, which will have to be developed at great risk in the next decade, hopefully through broad international cooperation.

Jan 1, 2004

Thermal barrier coating (TBC) systems provide thermal insulation to high temperature for aero¬propulsion. A fracture mechanical model developed earlier for multilayer systems is applied on TBC to realize superior performance by enhancement of fracture resistance. Functionally gradient materials (FGM) solution concept is the basis of approach followed here. A few realistic FGM TBCs are considered in the analysis in addition to a conventional TBC as the base case and a hypothetical worst case with YSZ-YSZ interface. Parameters like number, composition and thickness of graded layers and elastic modulus are considered for the analysis and quantitative improvement of fracture resistance of TBCs. The analysis is confined to deep crack with crack size to width ratio as 0.5.

Jan 1, 2010

By Judith S. Chan

With the increasing awareness of the need for the reduction of carbon emissions globally, geothermal energy, which offers a potential for cleaner energy generation, is one potential new source. In Alberta, these geothermal resources are likely to be found in the sedimentary basin, or in the deeper crystalline basement rocks. Alberta exhibits a very low geothermal gradient compared to other existing geothermal fields located in areas of volcanic and tectonic activity. To mitigate this effect, the focus in Alberta will involve the development of engineered geothermal systems (EGS) in the target resource. The first goal for EGS research and development is to develop a detailed geological-geophysical characterization of selected sites to delineate potential geothermal reservoirs in Northern Alberta. One of the selected sites is in the Fort McMurray area. The deepest well drilled in the oilsands areas of Northern Alberta is located just west of Fort McMurray. It has a depth of 2363 m and as such can provide details on the physical properties of the rocks, the state of stress, and the existence of fracture porosity toward geothermal investigations. To date, we have acquired temperature logs to study the change in geothermal gradient with depth, and a series of petrophysical logs to study the finer scale structure of the rock formations with vertical resolutions in the range of 0.05 cm to 80 cm. Our aim is to identify geological features such as zones of fractures in the basin and/or basement that could provide an indication of enhanced fluid flow potential ? a necessary component for any geothermal systems to be viable. Zero offset and walkaway vertical seismic profiles (VSP) were also conducted to measure the seismic responses at the borehole. VSP data can be used to delineate the structural and stratigraphic features surrounding the borehole that could not be resolved from surface seismic reflection data that are also available near the borehole. The full integration of well logs, VSP data and surface seismic reflection data are expected to provide a detailed characterization of the sedimentary basin and crystalline basement rocks of the Canadian Shield in Northeastern Alberta and will assist in future planning for drilling.

Jun 1, 2012

By T. H. Adair

"IntroductionCONTINUOUS casting of ferrous and non-ferrous metals is not a new innovation. Patents describing machines for continuous casting are on file as far back as the year 1842. In the middle of the last century, Sir Henry Bessemer conceived and built a continuous casting• machine for the production of mild steel sheet.The production of billets and slabs of both non-ferrous and ferrous metals is being carried out by the continuous method on a fairly large scale on this continent and abroad. At present, the volume of production of •copper and aluminum and their alloys in billet and slab form is much greater than the continuous casting of steel products. The new installation of a continuous casting unit at Atlas Steels, Limited, is designed primarily for the casting of alloy steel billets and slabs.As an introduction to the art of continuous .casting of metals, it is interesting to examine a few of the many devices which have been developed. As previously mentioned, Sir Henry Bessemer constructed a machine for the direct casting of mild steel sheet. His discoveries and ideas of continuously casting steel formed the foundation for the work of other pioneers in this field, all of whom have contributed to the improvement of this art through the ensuing years. The machines which will be selected for examination are those of Bessemer, Poland-Lindner, Williams, Ennor, and Junghans. The last unit to be discussed will be a modification of the Junghans machine recently installed at Atlas Steels."

Jan 1, 1954

By R. D. Lindsay

Originally the focus of Deak Resources Corporation Business Plan was to establish a method for treating small gold and possibly base metal mineral deposits located in the Kirkland Lake - Noranda area of Northeastern Ontario, Northwestern Quebec at a central treatment facility. Since the establishment of this original business plan in 1988 other processing options have availed themselves for handling the base metal ores off site at a central facility which may preclude their processing at Deak.The site selected for the Deak processing plant was Kerr Addison's Virginiatown operation. At the time this property was acquired from the Receiver following Golden Shield Resources' Bankruptcy in 1989 the mill had been processing in the order of 1, 100 SDT per calendar day through one processing module; a module originally designed to process 1,500 SDT/day of a free milling gold ore. This tonnage level however had not been achieved since 1966 when an average throughput of 1481 SDT per calendar day was recorded.In order to realize Deak's overall Business Plan it would be necessary to expand the mills processing capabilities to provide:(1) A 2200 SOT per day circuit capable of processing a free milling, medium work index gold ore;(2) a 1 ,000 SDT per day flotation and/or cyanidation circuit capable of processing refractory gold bearing materials containing refractory minerals (i.e. copper) that should be removed prior to cyanidation; and possibly(3) a 1200 to 1500 SDT/day base metal circuit capable of processing the broad range of Deaks' Base Metal Property ores. If this circuit were introduced it would be completed in two tonnage phases.Further, it was recognized when operations resumed under Deak in 1990 that the existing tailings dam was suitable for, and had sufficient capacity for additional gold tailings with necessary physical modifications and changes in disposal techniques (including the construction of containment storage cells) that would allow storage for an additional 3.4 million tons of gold ore tailings approximately 1.0 million of which has been deposited since 1990. The focus of Deak's long term tailings disposal strategy is to acquire the Barber Lake Basin which is currently adjoined to our main tailings system which will provide an additional 10 million tons of storage capacity.

Jan 1, 1993

By S. K. Sharma, Sanket Bacchuwar, Prabal Kumar Agrwal, G. V. Rao

"Iron ore processing industries play a vital role in the Indian economy. At present Iron ore of around +64% Fe is used for production of Iron through blast furnace. To produce +64% Fe from low/medium grade ores, crushing & beneficiation is compulsory. But during these processes, large amount of slime is generated. It is estimated that 18% -25% of tailing is generated during the processing of iron ore. The iron ore slime is discarded because of its particle size and chemical composition not being suitable as feed to the blast furnace. Although the fines/slimes can be agglomerated to larger particle, the alumina to silica ratio which is normally more than one pose serious problem during sintering process and subsequent smelting in blast furnace. The alumina content in the slime needs to be reduced for it to be used as the feed for blast furnace. The sample assayed 61.40% Fe, 7.68% SiO2, and 1.52% Al2O3, LOI 2.63% and all other elements were found in critical limit. A series of 27 tests were conducted by using a spiral for optimisation of process parameters to produce a pellet grade concentrate from the stacked slimes obtained from Kirandul. This paper deals with the optimisation studies of various parameters of a spiral concentrator and helps to utilize the fines from tailing ponds.INTRODUCTIONReserves of high-grade iron ores are diminishing all over the world at an alarming rate. As a result, alternative ways of augmenting and conserving precious and non - renewable natural resources are being seriously considered. One such attractive option is the recovery of metal values from slimes / tailings. Iron ore tailings containing around 48 - 60% Fe are generated from the iron ore washing plants and are disposed into tailing ponds without any further utility. These tailings in the form of slimes are not suitable in iron and steel making due to the presence of higher amount of gangue constituents. Several beneficiation techniques have been tried from time to time to reduce the gangue so that the beneficiated products could be effectively used."

Jan 1, 2016

By H. J. Chalmers

"Since the advent of large volume flotation machines, Cominco Ltd. has actively studied possible application of such machines to their various milling operations. A number of installations have been made and more are on the drawing board. This paper gives a description of these units, information as to choice of equipment, and information as to operating experience. Mechanical and operating details of six installations are summarized. Three different types of machines are discussed.Pine PointThe original Pine Point zinc flotation circuit comprised conventional roughing with two stages of cleaning. Over the years with increase in feed tonnage there have developed two adverse conditions; namely, a reduction in zinc concentrate grade coupled with an increase in MgO in the concentrate. This resulted in higher freight payments along with more severe smelter penalties. An intensive test program, in 1971, showed that the concentrate grade could be raised by 1.5 units of zinc along with a reduction in MgO from 0.8% to 0.47.. Subsequently this was done by adding two additional stages of cleaning using 16 cells of Denver 200-V's. The project was completed in January 1973 at a cost of $510,000 to give an estimated annual savings of about $390,000.Selection of the Denver Model 200-V was based on minimum floor space requirement, availability, and favourable operational and maintenance experience with Denver 100’s. As it happens it was possible to ""shoe-horn"" the 16 cells into place with a minimum of plant alteration. Some problems have been encountered with a tendency to ""sand up"" at high pH, particularly at the corners. Otherwise operational service has been very good."

Jan 1, 1974

By P. A. Riveros

This paper describes the leaching of the common copper minerals tennantite (Cu12As4S13), tetrahedrite (Cu12Sb4S13) and enargite (Cu3AsS4) in acidic media using Fe(SO4)1.5, FeC13 or 02 as oxidizing agents. At temperatures <100°C, tennantite dissolves slowly in Fe(SO4)1.5-H2SO4 media, and the rate is directly proportional to the area of the sized tennantite. The rate increases sharply with increasing temperature and the apparent activation energy is 69 kJ/mol. Increasing Fe(SO4)1.5 concentrations slightly increase the tennantite leaching rate. The kinetics of dissolution of disks of synthetic iron-bearing tetrahedrite in Fe(SO4)1.5-H2SO4 media are linear; the leaching rates are slow but increase significantly with increasing temperature, with an apparent activation energy of 120 kJ/mol. The dissolution of sized particles of natural Ag-bearing tetrahedrite in FeC13- HC1 solutions proceeds according to the shrinking core model, and both Cu and Ag dissolve at about the same rate, provided that the total chloride concentration of the solution is sufficiently high to solubilize the AgC1 reaction product. The leaching rates are slow, and the apparent activation energy is 116 kJ/mol. The addition of sulphate ions to the FeC13-HC1 system reduces the tetrahedrite leaching rate to values similar to those realized in the Fe(SO4)1.5-H2SO4 system. At <100°C, enargite dissolves slowly in either Fe(SO4)1.5 or FeC13 media, and the dissolution rate obeys the shrinking core model. The rate increases with increasing temperature and the apparent activation energies are 50-64 kJ/mol. The rate increases slightly with increasing FeC13 concentrations in 0.3 M HC1 media. The leaching of enargite at elevated temperatures and pressures was also investigated. Potentially useful leaching rates are achieved above 170°C, at which temperature sulphate, rather than sulphur, is produced. Lower temperatures (130-160°C) lead to fast initial leaching rates, but the dissolution of the enargite is incomplete because of the coating of the enargite particles by elemental sulphur.

Jan 1, 2007