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By R W. Drybrough

The program to increase production at Sherritt Gordon's Lynn Lake property, which began in 1956, included increasing the rope speed and the horsepower of the ore hoist at the "A" shaft. Because of the limited power sup-ply from the two 7,000-hp. hydroelectric plants, and the ? 3,600 hp. predicted for the combined hoisting requirements of the three production shafts, it was considered desirable to lessen the impact of this type of load on the relatively small power system by equipping all future hoisting arrangements with Ward Leonard direct-current drives. The manually operated 8-by 4-ft. hoist at the "A" shaft had a rope speed of 1000 f.p.m., and was driven by a 385-hp., 380-r.p.m. wound rotor motor with liquid rheostat control. This A.C. drive was replaced by a semi-automatic Ward Leonard direct-current drive with a 515-hp., 566-r.p.m., shunt wound motor, providing a rope speed of 1,500 f.p.m. During several months preceding the con-version, all possible preparations were carried out to keep the changeover period to a minimum, and this resulted in a total shutdown time of twelve days. The capability of the "A" Shaft hoist was increased from 109 tons per hour to 134 tons per hour, and both mechanical and electrical maintenance were reduced considerably. The total cost of the conversion amounted to $130,000. The hoistmen who had been required for the manual A.C. drive were transferred to the new Farley shaft, and the reduction in operating labour costs of the "A" Shaft hoist

Jan 1, 1965

By Akihiko Nishiyama

Unmanned construction technology used for remote control operation of construction machines has some problems to solve compared with manned operation of construction machines, such as fatigue due to long-term operation or decreases in operational efficiency. To solve these problems, we recorded the viewpoints of operators in both manned and remote control operation and analyzed the differences. This paper reports on our discussion of improving the operability of remote control operation based on the analysis results.

Aug 1, 2013

By Charlie Harper

Open Pit Mining of Golden Band Resources? EP Gold Deposit Golden Band Resources Inc. (GBN:TSX-V) is Saskatchewan's newest Gold Producer. Located in the La Ronge Gold Belt of northern Saskatchewan, GBN has over 875 km2 of claims with 12 known gold deposits and 4 former producing mines. Production has begun at the Roy Lloyd Mine (Bingo Deposit), to be followed initially by our EP and Komis properties. Development of the underground infrastructure at the Roy Lloyd Mineis continuing and on schedule. Production from these deposits will feed our centrally located and 100% owned Jolu mill. We have our provincial environmental permits in place, and we have an established infrastructure including a 400 tonne-per-day mill, year-round road access, and access to grid power. Construction of the grid power line and the above ground tailings facility are now complete.

Nov 1, 2011

By Douglas R. Schmitt

In general, knowledge of the state of stress within the Antarctic lithosphere remains largely unconstrained due in part to Antarctica?s inaccessibility and because of the paucity of seismic focal mechanism solutions. As such, an important component of the ANDRILL project was to acquire new information on the stress directions and magnitudes within the upper crust. Extensive fracture mapping of the core and oriented ultrasonic televiewer logging were carried out to provide strong constraints on both stress orientations and the faulting regime. The first hydraulic fracturing stress determinations in Antarctica were also carried out to provide complimentary stress magnitudes. These measurements were accomplished using a wire-line transported hydraulic fracturing system consisting, essentially, of two synthetic polymer packers that were inflated to isolate the 1-m long pressurization interval. The tests were conducted at the end of the drilling and logging in a ~130-m section specially drilled below 1000 mbsf (nearly 1500 m from the rig floor) for hydraulic fractures. This zone was drilled primarily through competent, dense, and low permeability diamicts. The core fracture and televiewer logging information was used to site twenty separate measurements. Classic hydraulic fracturing pressurization records with unambiguous breakdown and fracture closure pressures were obtained in about half of the measurements. The remaining tests provided fracture propagation and closure pressures that are consistent with the classic breakdown curves, but they did not include a clear breakdown pressure and are indicative of the reopening of either natural or drilling induced fractures in the wellbore wall. The preliminary analysis of the results are in generally good agreement with the stress directions indicated by the core fracture logging and the stress regime suggested by the character of the drilling induced core fractures.

Jun 1, 2012

By T. K. Akopyan, E. A. Naumova, V. V. Doroshenko, N. A. Belov

"A qualitative and quantitative analysis of the new Al-Ca-Mn-Fe phase diagram in the region of the aluminium corner is carried out using both thermodynamic calculations and experimental methods. Using the obtained data, the principal possibility of creating both cast and wrought sparingly alloyed aluminium alloys with calcium, manganese, scandium and zirconium at allowable iron contents of up to 0.4% that do not require solution treatment and quenching is justified. At the selected concentrations, the entire amount of manganese (1%) is practically included in the aluminium matrix, while calcium (~2%) and iron are in the multiphase eutectic, which has a fine structure. The joint introduction of 0.25% Zr and 0.1% Sc into the alloy leads to precipitation hardening due to the formation of the L12-Al3(Zr,Sc) phase during annealing. Based on the experimental data for the model multicomponent Al2CaMnFeZrSc alloy, it is shown that such alloys can combine high mechanical properties and good manufacturability during both casting and metal forming. This is due to the combination of a narrow temperature range of solidification with a fine eutectic structure.INTRODUCTION Hardening in branded aluminium alloys (both cast and wrought) is generally achieved by heat treatment of the T6 type, including quenching and artificial aging (Zolotorevskiy, 2007; Kaufman, 2004; Mondolfo, 1976). Heat treatment significantly increases the cost of the final products. Therefore, industrial companies are interested in developing alloys that can be hardened to the desired level without quenching. To solve this problem, alloys with scandium are the most suitable (Toropova, 1998; RØyset, 2005). This element (usually in an amount of ~0.3%) is one of the most effective hardeners in aluminium alloys, due to the formation of Al3Sc (L12) phase secondary precipitates, the size of which is less than 10 nm (Knipling, 2010; Fuller, 2005). These nanoparticles are formed during the annealing via decomposition of the supersaturated aluminium solid solution (hereinafter referred to as (Al)). This feature allows us to significantly increase the strength of aluminium alloys by simple annealing (at ~300°C), i.e., without heat treatment, including quenching. However, scandium is a very expensive metal, so its use as an additive is severely limited. The most effective method is the introduction of scandium together with zirconium (Lefebvre, 2009; Booth-Morrison, 2012). The optimal combination is the introduction of ~0.1% Sc together with 0.20–0.25% Zr, which, according to (Belov, 2006), gives approximately the same strengthening effect as the introduction of 0.3% Sc."

Jan 1, 2018

By J. B. Evans

"NORMALLY the duties of the exploration engineer and geologist cover the initial, and possibly, the most important phase of mining property evaluation; that phase being the presentation of an opinion of the property's ore reserve potential in terms of tonnage and grade. The prime objective of this pa-per is to outline one method of bridging the wide gap that lies between a know ledge of a property' s tonnage and grade potential and an appreciation of the value of that property in dollars and cents.THE PRESENTATION OF PROPERTY EVALUATIONThe engineer engaged on a mining property evaluation, regardless of whether he be an independent consultant, or a company employee, has as his goal, the presentation of his appreciation of the property's potential value or worth within terms of reference acceptable to his principal.To furnish a complete evaluation report, the evaluator must firstly study all aspects pertaining to the particular property under consideration, then present his appreciation of the property's worth in some tangible form. The ultimate presentation is one giving a Present Value of the pro pert y in terms of monetary exchange. Such an idealistic presentation is not always possible; typical preventives being -insufficient reliable information, limited time, Jack of ability and absence of definite direction."

Jan 1, 1960

By C. Carrasco

Caletones Smelter, Division El Teniente of Codelco Chile, has used Teniente Converter (TC) as the only smelting unit since November 2000. The modernization project considered the shutdown of the last reverberatory furnace, the installation of the fourth Teniente Slag Cleaning Furnace, the installation of a new fluidized bed dryer and the modification of the concentrate injection system into TC. The modernization project and related investments allowed for the increase of the smelting capacity up to 1.25 million t of concentrate annually.Next stage of the smelter expansion in the year 2004 considered the increase of the smelting capacity up to 1.44 million t/year. The expansion required technology modernization and the installation of the new equipment, such as concentrate injection system, oxygen plant, fluidized bed dryer and storage bin. Currently the annual smelting capacity is about 1.35 million t of copper concentrate, being limited by sulphuric acid plant treatment capacity. This paper presents the technology and production evolution in the Caletones Smelter in the years 2000 - 2006, demonstrating the potential of development and competitiveness of Teniente Converter as world-wide recognized smelting/converting reactor.

Jan 1, 2007

By J. A. Hudson

"The paper begins with a brief summary of Professor Müller’s formation of the ISRM and the contents of the previous six Müller lectures with their emphases on rock fractures. The geological origin of fractures is described via a deformational spectrum diagram and a matrix characterising the consequences of a sequence of superimposed deformational events. The different fracture frequencies encountered along lines in all directions through a fractured rock mass are explained. The value of computer modelling and simulation is demonstrated through an example of the effects of fracture zones on the distribution of the in situ stress field. The need to establish the validity of computer programs, i.e., that the modelling/simulation, does actually represent the rock reality, is discussed with reference to the work of the DECOVALEX project. Finally, examples are given of the effects of rock fractures on engineering design and construction, from pre-split blasting to caverns.INTRODUCTIONIt is a great honour to have been chosen as the recipient of the ISRM 7th Müller Award and I am grateful to the representatives of the International Society for Rock Mechanics (ISRM) National Groups who voted for me. In addition, I am especially pleased because my working life in rock mechanics and rock engineering has been devoted to understanding the geometry and mechanical properties of rock fractures and rock masses—which were the key subjects that Professor Müller promoted. In the ISRM 50th Anniversary Commemorative Book, Hudson and Lamas (2012), Professor Charles Fairhurst notes that on 24 May 1962, i.e., the day before the constitutional meeting of the ISRM took place in Salzburg, a reporter asked Professor Müller, “Do we know the strength of rock?”, to which Professor Müller replied, “For rock tested in the laboratory, yes. For a rock mass, no. This is what we need to determine. This is why we need an International Society for Rock Mechanics”. Also, in his Opening Address at the 1st ISRM Congress in Lisbon, Professor Müller, as the then ISRM President stated,“Many experts agree with me that discontinuity and anisotropy are the most characteristic properties of the material rock and that the properties of jointed media depend much more upon the fabrics bond of the unit rock block system than upon the rock material. Therefore any theoretical investigation of that material has to go its own ways, in the same way as the construction material of soils years ago suggested to soil mechanics its own methods, which differ greatly from the way of thinking of technical mechanics”."

Jan 1, 2015

By A. Hekmat-Ardakan

Conventional hypereutectic Al-Si alloys such as A390 are used principally for the casting of components used in wear applications requiring abrasive resistance such as in engine or compressor blocks. A comprehensive study was undertaken to investigate the potential of improving the mechanical properties of these alloys by the addition of magnesium. A thorough thermodynamic study of the effect of the addition of Mg to the conventional A390 alloy showed that Mg2Si starts to form as a primary phase at 4.2% Mg as well as in the products of the binary and ternary eutectic reactions forming the matrix. Experiments were carried out in producing castings with different cooling and solidification rates of alloys with up to 10% Mg. Mg additions were found to increase the hardness over the as cast alloy due to solid solution strengthening. Also, T6 heat treatment greatly improved the tensile properties of these alloy compositions due to the strengthening effect of the theta-Al2Cu phase. The elongation of these alloys generally decreases marginally with Mg content. The most significant property improvement of the alloys with higher Mg content is the substantial increase in wear resistance. This is attributed to the dispersion of smaller particles of Mg2Si and their coherence with the matrix as compared to the large Si particles in the conventional alloy. A new rheoforming process for A390 is presented that improves the processing of the semi-solid slurry. Structure modification elements were also added to refine the primary and eutectic silicon greatly improving the processing of the semi-solid slurry.

Jan 1, 2011

By W. A. Lang

"I.-IntroductionAn attempt bas been made in this paper to provide a basis for appraisal of the future of the coal briquetting industry in Alberta by outlining the processes used for briquetting various ranks of coal, by specifying the requirements of a briquetted fuel, by indicating .the status of the industry in the United States, by giving developments in Western Canada, by assessing costs of processing, and by discussing briquetting researches in progress. Much of .the detail bas been omitted since this might mask, rather than reveal, the more important phases of the problem. Reference will be made when possible to published articles where many of the details can be obtained.It should be stated at the outset that, in the writer’s opinion, there are three possible developments in Alberta as regards briquetting: (a) an expansion of the briquetting of the fines of • non-coking and coking coals of semi-anthracite, and of low and medium volatile bituminous rank; (b) the processing of the fines of high-volatile C bituminous coals; and (c) the upgrading of the lower rank high-moisture sub-bituminous coals. Details of the chemical and physical properties of these coals can be obtained in publications of the Research Council of Alberta (1, 2), and of the Fuel Research Station, Bureau of Mines, Ottawa (3).Semi-anthracite and low and medium volatile bituminons coals occur in the mountain areas of Alberta, where, during the upthrust of the Rocky mountains, the coal beds served as the sliding surface. This resulted in the coals being; crushed and consequently they contain a h1gh percentage of fines. In some cases they are high in mineral matter and require to be cleaned before being processed. However, the cleaning of fine coal is both difficult and costly. Both the amount of fines present in the mine-run coal and the amount of mineral matter associated with the coal have increased through the introduction of mechanized mining and through the recovery of coal by stripping operations."

Jan 1, 1950

By C. G. Bruce

"ON NOVEMBER 15th, 1950, the Department of Mines and Technical Surveys announced the discovery of vermiculite near Perth, Ontario. The announcement followed nearly a month of study to determine so far as possible the potentialities of the deposit and quality of the material from surface indications. The mineral was identified by the writer in the field among samples submitted by Mr. Arthur Powers of Stanleyville or, September 22nd, 1950. Within a week of the announcement, mining rights to properties covering a major portion of the deposit had been acquired by commercial interests.Hitherto, Canada has had to import her entire requirements of vermiculite. Prospects of .a domestic supply gave promise of considerable benefit to many industries, particularly the building industry, and to the consumer public. Should the deposit •prove large enough there was also the possibility of exporting to centres in the United States.Field and laboratory studies were continued at the Mines Branch during the winter of 1950-51 as opportunity occurred. It is the purpose of this paper to describe the results of these •preliminary investigations, to attempt to present the Stanleyville occurrence in its proper perspective with regard to similar occurrences elsewhere, and to review the salient features of the vermiculite industry.Properties and UsesVermiculite is a hydrated magnesium aluminum silicate. In appearance it resembles mica, having the same micaceous cleavage, but it differs from that mineral in being very soft, pliable, and inelastic. Colours range from black through dark olive-green and brown to almost colourless."

Jan 1, 1952

By Arthur Laing

"IT is indeed a pleasure to have the opportunity of addressing this group today. Not only does it give me the opportunity of meeting with representatives of what is considered by many to be the most dynamic segment of industry in Canada today, but it also allows me to talk about a subject of para-mount interest to myself, the development of the North, and to explain, if even only briefly, some of our beliefs and hopes in this regard.It is inconceivable that all lands north of the 60th parallel, representing 35 per cent of Canada's total land area, which we believe contain a great natural resource potential, will remain as an undeveloped portion of Canada. The re-sources are there, although the people and private industry are as yet not there in sufficient numbers.It has been estimated that in the west and north of Canada there are 1.6 million cubic miles of sedimentary rocks. Of this figure, 342,-000 are thought to lie in Alberta, 115,000 in British Columbia and about 1 million cubic miles are thought to lie in Canada's northern regions, the bulk in the Arctic Islands. On the basis of apparent volumes of sedimentary rock, we estimate that as much as 13 billion barrels of petroleum may lie beneath the permafrost of the North-west Territories, another 3 billion barrels in the Yukon Territory and 33 billion barrels in the Arctic Islands. This is, indeed, a rich and elusive prize, and one which must be sought with a view to fulfilling demands on the production of petroleum."

Jan 1, 1966

By Barbara Kirby

Mining Industry Human Resource Council Who we are: National Sector Council for the Minerals and Metals Sector 18-person Board of Directors Over 100 Industry Volunteers PPP - Funded by HRSDC and industry What we do: Identify national HR challenges and opportunities for the Canadian mining industry Create national solutions through collaboration, partnerships and Synergy

Oct 1, 2010

By R. Burnette

Gold has been mined from a variety of deposit types that range in age from Archaean to Recent. The large variability in the geological settings of the gold deposits implies transport and concentration of gold by magnetic, hydrothermal and sedimentary processes. The factors that control the concentration of gold at certain sites and the grade estimation thereof remain major topics of debate. Due to the complex nature of the Witwatersrand Basin a mineralogical study, including mineralogical, petrographic and geochemical investigation was launched on TauTona Mine in order to characterize the various reef facies. The aim of the investigation was to determine if a correlation could be found between macroscopic characteristics of the reef, hanging wall and footwall, and the microscopic nature of the ore (especially gold grade). Petrograpgic and mineralogical results indicate that a correlation exist between gold, detrital and hydrothermal sulphides, uraninite, carbon, detrital heavyminerals and phyllosilicates. No correlation exist between gold and Mg, Fe or S. It appears that clast supported reef is of higher wade than matrix supported, but more work is suggested. No correlation exists between reef thickness and grade. The reef samples had the lowest phyllosilicate content compared to the hanging wall and footwall samples with pyrophyllite the most dominant. All of the correlations diagrams showed significant scatter and suggests a multi- factorial mineralization model. Gold distribution is also controlled by sedimentary features and thus it is not possible to select a single model for the formation and distribution of gold. It is evident that both sedimentary and hydrothermal factors influenced the mineralization and gold distribution on TauTona mine. It is thus essential that all related theories be incorporated in the development of a grade prediction model.

Jan 1, 2011

By D. O. DeGagné, J. F. Archibald

Spray-on polymer linings, as partial or full replacement for traditional forms of area rock support, have seen rapid growth in interest within Canada. A wide variety of lining types, ranging from polymer chemical to water-based cementitious materials, have been developed and commercially introduced to the underground mining market. Following approximately one decade of development work, several general conclusions have been reached regarding the performance of this class of area support media, these being that: health and safety assessment of the broad range of materials has shown the majority of them to be acceptable and safe for underground use; significant ground support potential can be offered by them, being equivalent to or better than capabilities offered by traditional support forms such as bolt-and-screen or shotcrete, and; their abilities to be rapidly deployed and provide near instantaneous support restraint offer considerable operational and cost benefits to underground operators. A review of currently available liner materials, their historic development within the Canadian mining industry, and overviews of support, health and safety, operational considerations and cost benefits are provided in this paper.

Jan 1, 2001

By J. Keith Haddock

"The Luscar Mine is a metallurgical coal mine located in the foothills of the Canadian Rockies, 41 km southeast of Hinton, Alberta. The mine is operated by Cardinal River Coals Ltd., a 50/50 joint venture between Luscar Ltd. and Consolidation Coal Company of Canada. The mine produces a high quality medium volatile metallurgical coal which is sold on the export market principally to Japan and South Korea. Operations consist of a surface mine with capacity to produce 3.0 million tonnes per year and an underground mine which is currently mothballed due to market conditions.GeologyBedrock units within the Luscar minesite are of Devonian to Upper Cretaceous age. The commercial coal measures in the area are, however, confined within the Lower Luscar Formation. The Luscar Formation consists of a 460-metre thick sequence of interbedded sandstones, shales and coal seams. The sequence is primarily deltaic in origin, and is bounded to the north and south at the Luscar mine by tectonically induced thrust faulting.The only mineable coal seam at Luscar is referred to locally as the Jewel seam. Average thickness of this coal measure is usually 10.5 m to 14 m, although in some areas folding and faulting has produced ""pods"" of coal from 15 m to over 40 m thick while in others the structural deformation has thinned the coal to 3.0 m to 4.6 m. Waste within the Jewel seam seldom exceeds a metre of shale, carbonaceous shale or infrequent sandstone stringers.Reserves and Coal QualityProven surface mineable reserves, based on pit scheduling through 1996, are 50.8 million raw tonnes. An additional 19.2 million raw tonnes are contained in possible extensions to the present planned operations. These surface mineable reserves are considered to be those reserves within 155 m of the surface. Underground reserves, located within 770 m of the surface show that 25.7 million raw tonnes have been proven to date in additon to 27 .5 million indicated and 260 miIJion inferred.Coal specification at Luscar Mine is as follows:"

Jan 1, 1985

By Tom Demorest

SMART is an association of mining companies that meet regularly to coordinate the technology development needed by the mining industry. Since 1995, the member companies and institutions have directed research and influenced the manufacturers and suppliers to improve surface mining technology and services. SMART actively supports learning seminars, collaborative research projects, and user groups. Members of SMART include some of the major surface mining companies in North America and Australia. These companies have recognized the value that collaboration can bring to the needs of individual organizations as well as the global mining industry.

May 1, 2009

By D. A. Beattie

Three novel dextrin polymers of varying functional group chemistry but similar molecular weight have been used to depress talc in single and mixed mineral studies. The mixed mineral system was a model sulphide ore consisting of talc, pentlandite, and chalcopyrite. Adsorption isotherms for the three polymers on both valuable and gangue mineral phases were determined to give initial clues as to the ability of the polymers to depress talc. Flotation testing revealed a distinct hierarchy of effectiveness of the polymers in the depression of talc in the single mineral system (MP Dextrin > CM Dextrin > Dextrin TYM), reflecting the observed adsorption affinity and adsorbed amount of the polymers on talc. However, a different order of effectiveness was observed for talc depression in the mixed mineral system (CM Dextrin > MP Dextrin > Dextrin TYM). Competition between the valuable and gangue mineral phases for uptake of MP Dextrin is responsible for its observed decrease in efficiency in mixed mineral flotation. All three polymers were found to be reasonably selective in their action, although at high dosages the polymers began to affect the flotation of the valuable minerals.

Jan 1, 2006

By Doris Stüben, Geoffrey P. Glasby, Akira Usui, Jörg-Detlef Eckhardt, Bruce W. Mountain, Zsolt Berner

"Abstract - Twenty-seven marine Mn and Fe deposits chosen for their diverse origins have been analyzed for five platinum-group elements (PGE). The PGE display their highest concentrations in hydrogenous Mn crusts and nodules, lesser concentrations in diagenetic nodules and two to three orders of magnitude lower concentrations in hydrothermal Mn and Fe crusts. This difference of behavior reflects the well-known fractionation of Mn and Fe from the other transition elements, rare earth elements (REE) and PGE in hydrothermal Mn and Fe crusts. Pt, Ru, Rh, and Ir show a close geochemical coherence in these deposits and are differentiated from Pd which shows a negative anomaly with respect to the other PGE in hydrogenous and diagenetic Mn deposits. Pd is less depleted than the other PGE and the Pd anomaly much less pronounced in the hydrothermal Mn and Fe crusts relative to the hydrogenous and diagenetic Mn deposits.Stability field diagrams show no evidence for the oxidation of Pt to the tetravalent state in seawater as suggested by some authors. Rather, Pt appears to be present in seawater as Pt(OH)2 0. Adsorption of Pt(OH)2 0 onto the surface of Mn and Fe oxyhydroxide minerals may explain the enrichment of Pt in marine Mn deposits. However, Pt metal is the thermodynamically stable solid phase of Pt under seawater conditions and reduction of Pt(OH)2 0 to Pt metal, particularly in the vicinity of the oxygen minimum zone, is possible, although the high Ce/La ratios of the Co-rich Mn crusts do not support this hypothesis. Pt, Ru, Rh, and Ir display their maximum concentrations in the Corich Mn crusts. This may reflect, among other things, the low growth rates of these deposits. The stability field diagram of Pd shows that Pd is undersaturated in seawater and occurs in seawater dominantly as PdCl4 2- and anionic mixed-hydroxide-chloride complexes. This would explain the anomalous position of Pd among the PGE with respect to its uptake into marine Mn deposits. A study of inter-element associations indicates that the incorporation of the PGE from meteoritic dust plays only a minor role in the uptake of these elements into marine Mn deposits. The PGE remain the most poorly studied group of elements in marine Mn deposits. The data presented here emphasize the need for the establishment of a more comprehensive database of the PGE in marine Mn deposits in order to understand more fully their uptake into marine Mn deposits and their pathways through the oceans."

Jan 1, 1999

By lchimura. R. .

Japan Oil, Gas and Metals National Corporation (JOGMEC) and Centro de Investigation Minera y Metalurgica (CIMM) commenced a five year project from 2001 to modify the treatment of the furnace dust from Teniente converter containing harmful elements like arsenic and lead. The project was supported by Japanese and Chilean governments, and a demonstration plant was installed and operated at Las Ventanas Smelter and Refinery (Division Ventanas CODELCO). The basic and detailed engineering was made by Mitsui Mining and Smelting Co., Ltd (MMS) based on the joint study among JOGMEC, CIMM and Division Ventanas CODELCO. Arsenic in flue dust is lixiviated by sulfuric acid and fixed as crystalline ferric arsenate, where leachability of arsenic will be lower enough than the regulation, 5mg/I by TCLP (Toxicity Charactaristic Leaching Procedure) of USEPA. On the other hand, the recovered copper from the dust will be fed to the copper production process at Las Ventanas Smelter and Refinery, while zinc will be recovered as the exportable product. As introducing the crystallization and growing stage, the stable crystalline ferric arsenate formation can be achieved under the normal pressure.

Jan 1, 2007