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By B. Stuckert, P. Sheehan, J. Balfour, B. (Manas) Das, D. Fawcett

"With the growth of large scale surface mining operations, waste disposal and stability of waste dumps pose a challenging problem to engineers. Vibrations due to blasting operations proximal to these dumps further complicates dump design. Many dumps which are statically stable may become unstable due to the effects of blasting vibrations.A joint project between CANMET and Smoky River Coal Ltd. has been initiated to study the dynamic stability of waste dumps. The study involves development of an analytical algorithm combined with field monitoring to assess dump performance.Another objective of the study is to provide baseline data for a vibration attentuation relationships for sedimentary rock (coal) environments: most studies to date are for base metal mines. The effect of dump thickness on vibration response is also addressed.The key objective of the study is to present a methodology for assessing the dynamic stability of waste dumps. Implicit in this methodology are a number of assumptions concerning vibration attenuation in sedimentary rock environments, and response of the dump material to induced vibration. Where possible, these assumptions have been compared with monitoring data as a check on their validity."

Jan 1, 1989

By Hooman Askari-Nasab

Open pit mine plans define the complex strategy of displacement of ore and waste over the mine life. The objective of the mine plan is to maximize the future cash flows within the technical and physical constraints. Various mixed integer linear programming (MILP) formulations have been used for production scheduling of open pit mines. In the MILP formulation the slope constraints guarantee that all the overlying blocks are mined prior to mining a given block. Traditionally, the slope constraints have been modeled with cone templates representing the required wall slopes of the open pit mine. The overall pit slopes constructed by these templates are a function of the width and height of the geological block model. Therefore, the overall slopes are fixed in one bearing. This paper presents a general MILP model for open pit mine scheduling with variable slopes constraints. The methodology utilizes a directed graph to capture the precedence of extraction of blocks and pit slopes in different bearings. Depth-first-search algorithm was used to traverse the graph for constructing the slope constraints in the MILP problem. TOMLAB/CPLEX was used as the implementation platform to efficiently integrate the mathematical solver package CPLEX with MATLAB. A case study on intermediate scheduling of an iron ore mine over twelve periods was carried out to validate the models.

Oct 1, 2009

By A. A. Abdul-Latif, A. Sahin

"The phosphate deposit, located in the Abu Tartur plateau between the Kharga and the Dakhla Oases in the southern part of the Western Desert of Egypt, is the largest of its kind in the country. The phosphates are found in two horizons referred to as the Lower and Upper Phosphate Horizons within the Late Campanian Sibaiya Formation which belongs to the Nubia Group.This paper presents the results of a geostatistical study on the main phosphorite bed at the base of the Lower Phosphate Horizon which contains almost all the commercial reserves in the area. After semivariogram modeling for the phosphate thickness and accumulation, ordinary block kriging was employed to estimate the values of these variables in blocks of400 m by 400 m dimensions. The kriging results, which are presented in the form of contour maps, can be of considerable use in both future exploration and exploitation of the deposit. The grade-tonnage relationship based on the grade estimates derived from the corresponding thickness and accumulation estimates indicates the existence of 453.9 x 105 tonnes of phosphate above a cut-off grade of 18% P2O5. The mean grade of this tonnage has been estimated to be 25.77% P205"

Jan 1, 1990

By Robert B. Parsons

"Income tax legislation is not keeping pace with federal and provincial environmental legislation. There is a vast array of new environmental regulations at various stages of implementation across the country. Unfortunately, there are serious concerns about the deductibility of significant payments which mining companies will be required to make under these new rules, and the Department of Finance seems to be reluctant to act on these concerns. IntroductionWhile the federal and provincial governments are racing ahead with obvious fervour to introduce new envirorunental laws, the tax rules relating to envirorunental costs are being allowed to lag far behind. In a nutshell, the tax treatment of envirorunental costs is not keeping pace with the new envirorunental legislation.One of the most serious concerns of the mining industry is the deductibility of mine reclamation or closing costs. The producing provinces are well advanced down the road toward mandating upfront deposits, bonds, or similar financial guarantees to protect the envirorunent from the operation and eventual closure of a mine. These requirements are not small. In some instances, they can amount to tens of millions of dollars. And, if there is no tax deduction for these sums when they are set aside by the mining company, then the costs have to be paid out of the company's after-tax earnings."

Jan 1, 1991

By A. I. A. Salama, M. W. Mikhail, R. J. Mikula

"The Coal Research Laboratory (CRL) of CANMET along with other research organizations in coal-producing countries envisage major benefits from computer applications in coal preparation, Some of these benefits are greater system flexibility, improved coal preparation plant performance efficiency and efficient utilization of manpower, all of which result in economic benefits. Computers can be applied for both on-line and off-line purposes; this paper focuses on the on-line applications from the process control point of view.A critical discussion of the different analog and digital process control systems is presented. Recent developments in Great Britain, West Germany, Poland and Australia on automation and instrumentation using on-line measurements of coal ash and moisture contents are identified.The CRL research and development strategy aimed at achieving on-line computer control of an automated coal preparation plant is presented.IntroductionIn the past twenty years an enormous progress in the area of computer technology has been noticed. Computer applications in industrial processes offer greater system flexibility, improved plant performance efficiency and efficient utilization of manpower. Significant computer control development in mineral processing has already been achieved. Although progress has been made in the area of computer applications in coal preparation, more effort is needed to utilize the full potential.The computer applications in coal preparation can be viewed as off-line and on-line. Considerable progress has been reported in the area of off-line computer applications, especially in the areas of modelling, performance evaluation/prediction and statistical analysis. However, only modest progress in on-line applications has been reported(1-7). This paper will focus on: online instrumentation and process control applications, different analog and/or digital control systems, on-line automation and instrumentation in other countries and CRL strategy toward pilot plant automation."

Jan 1, 1985

By Göckmann. Klau

"IntroductionCopper has been recycled ever since its discovery. Even in Graeco-Roman times recycling of this resistant, and thus valuable material was carried out as a matter of course. Just take, as an early example, the Colossus of Rhodes: after the figure collapsed during an earthquake, the bronze parts were melted down into ingots and sold.Copper is a material which can be recycled again and again because copper produced from recycling is not different from copper originating from primary materials. This is mainly due to electrolytical copper refining whereby not only the base metals but also the precious metals can be removed. In contrast, with aluminum and iron only the more electropositive elements can be removed by refining, and the resultant scrap must, therefore, be sorted mechanically into various alloys for subsequent smelting.The recycling rate for different base metals is given in Table 1. Despite this ideal prerequisite, the generally quoted recycling rate of copper of about 40070 appears rather low. However, it must not be forgotten that the recycling rate is defined as the ratio of the annually utilized quantities of copper scrap and the annual production figures (Table 2). Moreover due to the economic growth over the last 30 years the availability of copper from scrap materials is lower than its consumption because copper is principally employed in very long-life consumer durables and only returns to the recycling circuit after many years. The average time for the copper of some goods to be recycled is detailed in Figure 1."

Jan 1, 1992

By J. P. McGeer

"With the ever-increasing flood of new science and technology has come a new approach to design. The combination of these factors has produced an ever-accelerating pace of materials substitutions.Examples to illustrate the points made above will be given. An overview of the current new materials fields will follow. Finally, the particular nature of the challenge for Canada will be discussed. IntroductionThere are a number of forces currently at work which make it mandatory that the Canadian resource sector re-examine its strategies and policies. The author thinks there need to be very significant changes in the business plans of Canadian mineral processing corporations. Current changes in our environment demand such a reaction.The changes in our environment include more rap id substitution of materials; a significant alteration in design philosophy; the global economy; and market saturation and market diversification in dev eloped countries.This paper will cover the changes and illustrate how they will affect the Canadian resource industry. It will show some of the ways that Canadian corporations are reacting to maintain profitability. Finally, some policy issues will be considered"

Jan 1, 1988

By Dallas W. Davis

"Since May 1980, New Brunswick has called separate tenders for the right to explore and develop several potash prospects, as well as areas underlain by Alberta oil shale. These tender calls had in common the provision for a basic ad-valorem royalty, combined with sharing of cash flow after exceeding a 15-20% discontinued cash flow rate-of-return threshold. In the case of potash, the bidding variable was a share of cash flow, but for oil shale it was exploration expenditures committed, with the cash flow sharing to be negotiated at the time of application for a production lease. The Millstream potash occurrence, previously discovered by government drilling, received five bids (21.1% highest), the Dorchester ""grassroots area"" with four surmised drill targets apparently received no bids, and in the case of oil shale there were only two bids on the one block previously subjected to the most exploration.It is concluded that New Brunswick will not be successful in awarding the potash or oil shale rights in return for a comparable level of basic royalty and cash flow share as in the case of Millstream, unless it spends money in discovering prospects or sharing the exploration risk with companies. The approach is likely to work for oil shales only if current exploration proves the existence of much high-quality material or a definite trend of real increases in the price of oil is again established. Undoubtedly, it continues to be desirable to assure an on-going stable investment climate through award of potash and oil shale rights under terms which provide for a return that the public and future governments will consider fair. This could mean that some form or risk sharing with companies would be advisable."

Jan 1, 1983

By J. E. Dutrizac

A pyritic Zn-Pb-Cu ore waspercolation leached with acidified ferric sulphate solutions; zinc and copper were leached, lead was oxidized, but not dissolved, and pyrtte was essentially unattacked. High zinc extractions were achieved after a few months leaching, and substantial zinc solution concentrations could be produced by recycle of the oxidized solution. The leaching rate was generally controlled by the transport of the ferric sulphate oxidant. Zinc extractions increased with increasingferric ion concentration or flow rate, but were essentially independent of the concentrations of sulphuric acid, ferrous sulphate, cupric sulphate or chloride ion. The leaching rates were insensitive to the height of the ore column once a minimum height had been exceeded (0.8-1.0 m). Elemental sulphur was the principal sulphidic reaction product, but variations in the ratio of sulphur to sulphate produced anomalous temperature effects.

Jan 1, 1979

By T. Yalcin

"This paper describes the development of a process flowsheet designed to provide high dewatering rates and to bring about savings in tailing disposal costs. The flowsheet comprises a hydrocyclone, a settling cone and a thickener arranged in closed circuit. The mill tailing, after pulp density adjustment, is fed to the hydrocyclone which yields two products. The underflow product is sent to the settling cone for further dewatering. The overflow product, together with the settling cone overflow, goes to the thickener which, with the aid of flocculants, gives a clear effluent and a relatively dilute underflow. The latter combines with the original mill tailing to form the hydrocyclone feed. Solids finally leave the system in the settling cone underflow which can reach pulp densities of up to 78%, making it suitable for direct disposal or for use as mine backfill.Some discussion is included for the selection and sizing of equipment required for this process. INTRODUCTIONDewatering is an essential process for the disposal of mill tailings which forms an added burden in milling practice, often with little or no return. It is, therefore, desirable to conduct this process as economically as possible. One way of reducing costs would be to increase the rate of dewatering so that savings can be made in the size of dewatering unit s which would lead to lower capital and operating expenditures.A common method of dewatering mill tailings is gravity sedimentation which is frequently carried out with the aid of flocculation. In most cases, flocculation greatly enhances the sedimentation process, but only until a pulp density of 50% to 55% is reached in the settled material.Centrifugal sedimentation in hydrocyclones can provide high pulp densities rapidly, but does not result in a clear effluent.This paper outlines a suitable combination of gravity and centrifugal sedimentations that results in an over-all high rate of dewatering. The system developed produces a material of high pulp density while at the same time giving clear effluent."

Jan 1, 1989

By Leslie McHattie, Sadek E. EI-Alfy

"The Maintenance Engineering Department at Carol Mining and Concentrating is currently in the process of introducing reliability concepts such as failure analysis, rework elimination, predictive maintenance, computerized maintenance history analysis, etc. to improve the over-all maintenance function in the mine and concentratormaintenance areas. Some current initiatives include:• Implementation ofan infrared thermographic scanning program.• Ultrasonic inspection of shafts for all critical equipment in the mine and concentrator areas.• Non-destructive testing of all major welds done by maintenance personnel.• Development of an effective vibration monitoring and analysis program for the production equipment in the mine (shovels, drills, haulage trucks, locomotives).• Failure analysis performed by maintenance engineers to identify the root cause of component failures on critical production equipment.• Computerized breakdown analysis to identify the recurring component failures which contribute significantly to high maintenance costs and production loss.• Implementation of a computerized maintenance management information system.This paper will outline the planned implementation ofthese initiatives, and others, and will also cover the status and results obtained to date."

Jan 1, 1992

By D. A. Stokes

"In October of 1980, Fording's 15 000-ton capacity clean coal silo was put into operation. The silo was unique in that it was designed to allow the mass flow of material, coupled with a sophisticated computer-controlled dynamic loadout/weighing system.On May 1, 1982, an explosion, attributed to a methane buildup, devastated the top of the silo. .As a contingent plan to minimize the effect of the production loss the conveyance to the silo top was reconstructed and the silo' was back in operation by mid-June 1982, although the silo top was left open to prevent further methane buildup. As dust emissions occurred during loading ofthe silo, an extensive study was undertaken to establish dust control for the silo, while at the same time providing methane detection and control.The study, conducted for Fording by the Cambrian Engineering Group of Calgary, involved an extensive search and investigation of existing coal silos. The study concluded that there IS no universally accepted method of controlling methane emissions in coal silos.The study also produced a unique conceptual design for handling methane, while at the same time, protecting the environment . Fording's Clean Coal SiloThe silo, located at Fording Coal's Fording River metallurgical coal operation, is utilized for the storage and load out of cleaned thermally-dried metallurgical coal.The silo was constructed in 1979 and 1980 to reduce unit train loadout times and to facilitate the handling of “special shipments"" of coal. The silo went into operation in October 1980, under manual control and utilized computerized, automated loading by February 198I.The silo is 21 m in diameter and 76 m high, with a nominal capacity of IS 000 live tonnes. The coal storage portion of the silo is 21 m in diameter and 48 m high, utilizing 2 steep-angled hopper outlets allowing mass flow of the stored coal during train loading. Each hopper has a control gate and a discharge chute, one chute for bulk loading, the other for trim loading of coal into the rail cars."

Jan 1, 1986

By Jacques H. Nantel, James F. Archibald

"Frozen tailings material may be required, in the future, to perform the support functions of underground backfill in mines located in zones of permafrost, notably in the high Arctic. To date, no knowledge of physical support parameters of such materials has been obtained in Canada due to the limited mining activity in permafrost regions. It is therefore judged essential that the important physical and mechanical properties relating to frozen tailings material be assessed.Innovative mining methods will be required to cope with the harsh environmental conditions that exist at mining sites in the Canadian Arctic. A preliminary laboratory study, in the absence of field trials at limited Arctic mining sites, has been completed in which the physical and mechanical properties of several types of representative mill tailings mixtures have been investigated. A variety of tests, to determine frozen slurry and pelletized tailings strength properties, moduli of compression, optimum water contents, deformation characteristics and the like, have been conducted.The results of this study will be used to establish guidelines for the suitability of tailings use in such northern mining environments. IntroductionFrozen tailings material has never been used to backfill underground openings in Canadian mines. At present only one Canadian mine, the Polaris Mine situated on Little Cornwallis Island, is investigating the use of frozen backfill. However, the Canadian North covers a large territory and potentially contains a large number of mineral deposits. The understanding of concepts related to mining activities in sub-zero frozen ground is therefore important.The implications of using frozen tailings as underground backfill material are far reaching both from the point of view of mine stability and disposal of tailings in the arctic regions.The strength of frozen materials (soil, backfill, etc.) may take on different meaning depending on the engineering situation. Both the concepts of rupture and excessive deformation need to be considered.The functions usually required to be performed by the backfill material in underground mines may be summarized asfollows:a) working floors; such as in cut-and-fill stopesb) stope wall support; for cut-and-fill and delayed fill stope~c) self-support when backfill is exposed on one face; during pillar recovery phases.For fill functions such as working floors, the short-term response of the frozen fill is the dominant concern. For the other fill functions, the long-term deformation response of the frozen fill, or creep, is of interest."

Jan 1, 1986

By M. K. Abel

"The Strathcona Mine is located in Levack Township on the North Range ofthe Sudbury Basin. The main orebody consists of pyrrhotite-pentlandite-chalcopyrite mineralization associated with an embayment of the footwall of the Sudbury Irruptive. A zone of massive chalcopyrite-cubanite-pentlandite mineralization occurs in a complex vein system in a series of mixed gneisses and breccias in the footwall. Vein widths vary from a few millimetres to 6 metres. In December 1979, this zone was estimated to contain 976,000 metric tonnes, with a grade of 9.31% Cu and 0.46% Ni. The vein system has a general strike of N 68°W at an angle of 60 degrees to the average strike of the footwall contact of the Irruptive. The dip of the vein system is 45 degrees sw. The strike and dip of individual veins in the system coincide with the directions that would result if a compressive stress had acted in a direction normal to the footwall of the Sudbury Irruptive, producing a conjugate set of fractures. The strike of the Irruptive at the Strathcona Mine is parallel to the long axis of the basin.IntroductionThe Strathcona Mine, owned and operated by Falconbridge Nickel Mines Limited, is located in Levack Township on the northwest rim of the Sudbury basin (Fig. I) . It is one of a group of nickel-copper sulphide ore deposits present along an 8.2-km section of the North Range of the Sudbury Irruptive. In the mines of the North Range, subunits of the Irruptive, going from hanging wall to footwall , include felsic norite, dark norite and dark norite breccia. The footwall complex at Strathcona includes the late granite breccia, which hosts a large proportion of the nickel-copper ores, and a compositionally variable group of brecciated and migmatized rocks, herein referred to as the feldspathic gneiss complex. It is within this latter group of rocks that the vein system of the Copper Zone occurs."

Jan 1, 1981

By A. L. Mular

"IntroductionSince the mid -1960s, automatic control of grinding circuits has become the rule, to avoid losses attributable to frequent circuit upsets associated with uncontrolled disturbances such as ore hardness variations. Higher capital costs of grinding equipment and corresponding operating costs-especially with respect to energy consumption-are major factors that continue to stimulate interest in grinding control.Grinding circuit control strategies depend upon the control objectives defined by the processing plant and are subject to constraints such as: maintain final per cent solids within some range, do not transport steel ball s out of the discharge trunnion, or do not overflow or empty the pump box and so on. Constraints depend on the nature of equipment employed within the grinding circuit and may actually determine the characteristics of the control scheme. Typical control objectives are:1. Maintain final particle size at set point by ,a. manipulation of fresh feed rate with circulating load maintained by manipulation of pump box water addition rate, orb. manipulation of pump box water addition rate with circulating load maintained by manipulation of fresh feed rate, where the methodology utilized to accomplish either (a) or (b) is dependent upon equipment/circuit constraints such as the availability of a variable speed pump.2. Maintain circuit throughput at a maximum by,a. manipulation of fresh feed rate subject to constraints on final particle size and variables such as power draw, circulating load and mill overload.3. Maintain mill load at set point by a. manipulation of fresh feed rate subject to constraints such as on power draw.4. Maintain mill power draw at set point bya . manipulation of fresh feed rate subject to mill load constraints. Often, a grinding control objective is dictated by the recovery vs fineness-of-grind characteristic that exists for downstream separation circuits. When recovery is relatively insensitive to size, maximum throughput in the grinding circuit is advantageous.The purpose of this paper is to review control strategies for primary ball mill grinding circuits, rod mill/ball mill grinding circuits and semi-autogenous grinding mill circuits. Primary sensors employed are highlighted and modern trends are documented briefly."

Jan 1, 1989

By F. J. Munn

"Since 1976, Cardinal River Coal s Ltd. has completed mining in eight pits. In each of these pits, at least one wall has failed, none by design, although not totally unexpected, yet there was no loss of production nor risk to personnel or equipment. Cardinal River Coals Ltd. has been successful in implementing a program to cope with failures and now feels justified in adopting more optimistic design parameters.The wall control program at Cardinal River Coals Ltd. is based on the premise that the walls are going to fail, monitoring is to confirm when. The program consists of monitoring slope movements and piezometric levels as well as structural mapping and visual inspections. In case of excessive movement, the frequency and intensity of the monitoring is increased. If a failure is impending, suitable remedial action is undertaken such as cutting down the crest, building up the toe, depressurization of the wall, artificial support, or a combination of the above. If remedial action is not possible, monitoring permits operations to continue up to near the time of failure.At the design stage, the emphasis is on identifying the potential failure mechanisms and the con sequences of failure. Once the potential failure mechanisms are identified, a monitoring system can usually be employed to give sufficient response time, and providing the consequence of failure is not severe and/ or remedial action can be taken to arrest the movements, then it is practical to mine pit slope s which have a higher probability of failure."

Jan 1, 1985

By J. P. Sims

Abstract - Ultramafic to mafic igneous intrusions of the Las Aguilas district form part of a belt of generally mafic plutonic bodies within medium- and high-grade early Paleozoic metamorphic rocks in the southern Sierras Pampeanas region, Province of San Luis. The intrusions host the largest known nickel sulfide resource in Argentina and contain significant Cu, Co and PGE mineralization (2.2 Mt at 0.5% Ni, 0.5% Cu, 0.035% Co). Sulfides at Las Aguilas Este, one of two principal mineralized zones, are hosted by a body comprising subvertically dipping units of predominantly orthopyroxenite and melanorite cumulate, with lesser dunite, harzburgite, norite, leuconorite, and amphibolite. The units are zoned horizontally from ultramafic to mafic compositions, representing primary magmatic zonation away from an original base or side of the intrusion. Intercumulus nettextured and disseminated aggregates of pyrrhotite-chalcopyrite-pentlandite are concentrated in the peridotitic zones and extend into melanorite. Whole rock major and trace element compositions, and olivine chemistry, indicate that the parent magma was gabbroic/basaltic with 100 (Mg/Mg+Fe) near 59, and resembles tholeiitic magmas generated in subduction-related arc, or back-arc settings. Unusually aluminous Cr-bearing spinel is compositionally similar to those in some synorogenic mafic/ultramafic plutons in magmatic arc settings. Relatively Ni-depleted olivines and low Cu/Pd ratios are indicative of magmatic sulfide segregation early in the crystallization of the magma. Early orthopyroxene saturation and virtual lack of clinopyroxene, in conjunction with sulfur isotope values up to +6.6 ‰, spinel compositions, and presence of graphite, phlogopite and magmatic hornblende, all attest to probable crustal contamination of the parent magma. Assimilation of crustal sulfur may have been crucial in the early attainment of sulfide saturation and resultant formation of magmatic Ni-Cu sulfide mineralization. Fabrics, textures and mineralogy of the intrusions and country rocks and U-Pb zircon dating indicate syntectonic-synmetamorphic emplacement at 478±6 Ma during the Famatinian (Ordovician) orogeny. Minor to locally significant recrystallization and deformation of mafic-ultramafic rocks and redistribution of sulfides and PGE occurred during and following the Famatinian orogeny. The Las Aguilas intrusion is one of several tholeiitic mafic-ultramafic intrusive complexes within an Ordovician arc - back-arc system in the Sierras Pampeanas. Aeromagnetic datasets and regional mapping suggest there is further potential for intrusion-hosted Ni-Cu mineralization along this eroded magmatic arc.

Jan 1, 1999

By Scott K. Palm, Neil D. Pearson, Jr. Read

"Uncertainty is an important feature of many investments, but it is especially important for mineral properties. Mine properties often entail large investments and fixed commitments. Managers in the mining industry often view price uncertainty as undesirable, due to the possibility that the price of the mined commodity will fall to a level that prevents the firm from recovering its investment and fixed costs. This paper identifies pitfalls in conventional valuation methods and outlines a new approach to valuation based on option pricing theory and dynamic programming. In the process, it identifies generic strategies for organizing mine production in ways that allow the owner to benefit from the uncertainty in mineral prices. IntroductionRisk is pervasive in the mining industry. The operation and maintenance of a mine may involve high, and unavoidable, fixed costs. A mine owner can only begin to recover these fixed costs if the price of the mined commodity is greater than the incremental cost of production. But the prices of many minerals are extremely volatile. The price volatility of copper has been significantly higher than the price volatility of a typical stock, for example. A mine owner cannot be sure that the price of the mineral product will remain high long enough for the firm to recover its capital and fixed costs.Mine owners are able to minimize their losses during periods when the output price is below the incremental cost of production by temporarily closing operations. During these periods they incur only fixed costs. While shut-downs help minimize losses, the y do not help the firm recover its initial investment. If output prices remain low long enough, the fixed costs and original investment may never be recovered. High fixed costs, therefore, lead to substantial downside risk."

Jan 1, 1986

By S. Demetrio

China has a traditional segment of Copper Smelters with its own Chinese technology, typically small in size from 20.000 to 50.000 tCu/a, and they are responsible for the processing and production of more than 600,000 tonnes of blister copper per year. For occidental experts, like one of the authors, it is not so easy to believe that they are profitable, because the size and the use of old Blast Furnaces, but they are with simple and effective production lines. The authors are convinced that China has a good alternative to improve theses old copper production lines with small innovative changes in its process arrangement, jumping to higher level technology, more efficient in production, productivity and cost, assuring copper as a raw material for the country and its high speed development. The key to improve that the traditional Chinese Copper Smelter is white metal as an extra raw material as a first step doubling the copper production from raw materials and the complete replacement of concentrates by white metal (WM) in a second step increasing it four times or more as the final goal. It is not so difficult nor expensive to make it happen, but there are a couple of questions for implementing this innovation in the copper smelter industry: 1 - Will the old fashioned mentality be open to this new direction for China being the biggest copper consumer on one side, and the biggest copper Primary Producers on the other hand? and 2 - Will they be open to follow this "win-win" strategic way for both ends of the copper market? We don't know if anybody will take up the challenge to improve it but our responsibility as a consulting expert and a university professor is to put the alternative on table for others to decide whether to implement it.

Jan 1, 2007

By O. E. Humeniuk, A. I. A. Salama, M. W. Mikhail

"The Western Research Centre (WRC) of CANMET operate a unique pilot plant facility where ongoing R&D on coal preparation and mineral processing is conducted. The pilot plant carries out two functions: coal preparation processing using state-of-the art technology and coal-liquid mixture preparation with intensive cleaning circuits that can also be used for mineral processing. In total, the pilot plant includes more than 30 different flowsheet options. The facility is dedicated to small and fine coal, and designed to be flexible and versatile.This paper describes the use of a pilot-scale facility as a research tool for process control development, fine coal beneficiation, development of coal-liquid fuels technologies, development of process models and testing and evaluation of new developments. The pilot plant is used to assist in resource development by evaluating and optimizing flowsheet selection, and producing sufficient samples for utilization tests. The facility is also an important tool for evaluating and testing samples from troublesome circuits of operating plants to find means to optimize and improve recovery, particularly of fines circuits.Detailed examples are given to demonstrate the role of a pilot scale facility in coal preparation R&D, coal industry development and optimization of coal processing operations. These examples include the development of heavy-medium cyclone computer control system, detailed evaluation of beneficiation of a coal deposit with high clay content, development of column flotation, and its role in fine cleaning circuits and treatment of ultra-fines in relation to intensive cleaning, the importance of testing coals in different processes, and cleaning processes influence on coking quality and other utilization applications. The potential of the facility for helping the mineral industry is also described."

Jan 1, 1992