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By R. J. Hundermark, K. van der Merwe, L. R. Nelson

Taphole integrity is critical to all furnaces, but it is especially important in high intensity electric furnaces processing matte and metal of high superheat. Key furnace dimensions are the electrode proximity to the taphole, hearth sump below the taphole and the shape and location of the taphole in the furnace wall (e.g., circular versus rectangular furnace). In addition, electric furnace power density needs to be matched appropriately to any configuration to achieve operational reliability and furnace integrity. The role of furnace dimensioning is generically reviewed across many pyrometallurgical processes to explore potential impact on furnace taphole performance. Some empirical furnace dimensions and power density ratios of industrial furnaces are then compared to explore to what extent they may indeed influence taphole integrity.

Jan 1, 2015

By D. G. Klaren, E. F. de Boer

Self-cleaning fluidized bed heat exchangers have demonstrated unparalleled performance internationally for the implementation of indirect heat transfer in severely fouling fluid environments. The ingenious configuration of recirculated cleaning particles through the tubes of vertical shell and tube heat exchangers provides the ability to solve any problems that arise as a consequence of tube-side fouling during indirect heat transfer to process fluids or slurries. In most cases, the cleaning particles consist of chopped metal wire, however other process-specific materials have been used. In addition to the mitigation of fouling effects, a number of other significant benefits for slurry heating are afforded by the mode of operation of the self-cleaning fluidized bed heat exchangers. Increased turbulence at the slurry/tube interface is imparted by the action of the fluidised particles, resulting in very high heat transfers at relatively low liquid velocities. Furthermore, given the thixotropic nature of most process slurries, the action of the fluidised particles imparts additional shear to the process slurry, resulting in shear thinning effects with a consequent reduction in pressure drop and enhancement of heat transfer across the heat exchanger. The benefits provided by the self-cleaning fluidized bed heat exchanger make it the ideal option for the indirect heating of laterite nickel slurry for High-Pressure-Acid-Leach (HPAL) plants. This article explains the principle and application of the self-cleaning fluidized bed heat exchanger technology for the processing of laterite nickel and cobalt slurries in HPAL plants. It also presents an elegant method to revamp existing direct heated laterite nickel and cobalt processing plants into an indirect heated configuration employing self-cleaning fluidized bed heat exchangers.

Jan 1, 2004

By D. A. Cormode

"INTRODUCTIONPine Point Mines, operated by Cominco Ltd., is located approximately 55 miles east of Hay River, N.W.T. by the southern shore of Great Slave Lake.The milling operation commenced in the fall of 1965 at a design capacity of 5,000 tpd. An addition which came on stream late in 1968 raised the nominal capacity to 8,000 tpd. Currently the milling rate is 11,000 tpd.The lead and zinc sulphides occur in dolomite host rock. Typical feed grades at present are 2% lead, 5.5% zinc and 5 % iron. When dolomite is present even in relatively minor amounts in the zinc concentrate, it presents serious treatment problems and causes inefficient operation of electrolytic zinc refineries.By 1972, it had become apparent that magnesium rejection in the form of dolomite was deteriorating because of increased plant throughput of less amenable ore. This paper will briefly outline the Pine Point zinc flotation circuit and will discuss the two phase program for reducing the magnesium level in the zinc concentrate. The program included changes and alterations to the flotation circuit and the construction of an acid leaching plant."

Jan 1, 1977

By Pierre Rocque

The Red Lake Mine is located approximately 600 km northwest of Thunder Bay. This 545 tpd (600 tons/day) underground narrow vein gold operation is set to produce in excess of 14.8 tonnes (475,000 ounces) in 2001 at a cash operating cost below 75 U$/oz. The high-grade nature of this deposit (>55 g/t or >1.6 opt) coupled with its complex geological environment and relatively deep location dictated the choice of a very selective primary mining method, Mechanized Overhand Cut and Fill. In addition to geological challenges, mine design issues such as material handling, ground stability and requirements for yieldable ground support are also discussed in this paper.

Oct 1, 2001

By J. M. Hemstock, H. L. Ames

THESE forums have been held annually since they were introduced by Mr. L. E. Djingheuzian in 1957. The response of millmen to questionnaires such as the one this year is ample evidence of the interest these create. This year's topic is unlike those of past years since it is an attempt to understand a new concept of grinding rather than to improve the old. Before, we were thinking in terms of 2-5 cents improvement in grinding costs, now we will be discussing savings of 15-2 5 cents. As a background for this forum we will begin by summarizing the major controversial issues relating to grinding with steel, many of which will undoubtedly apply to pebble milling. Our •task to-day is to learn what has already been done in pebble milling and obtain a fair overall view of this method of grinding.

Jan 1, 1961

By Barara Rose

Presentation Outline ?Introduction of BMS ?Resource Integration Process ?Methodologies ?Tools ?Case Studies ?Zone 01 : 725 SOZ ?Zone 16/17 : 1000 NRP ?Conclusions

Oct 1, 2010

By P. -M. Tardif, S. Outalha, R. Le

"This paper proposes a new direction to implement an underground mine communication system. It presents actual underground communication systems and discusses their technological limits. A new system based on a wireless local area network (WLAN), together with its main systems characteristics, is then proposed. This paper also presents an experimental protocol for radio frequency propagation measurements. Finally, the paper describes the projected implementation of a WLAN in an experimental mine. IntroductionDuring the last decade, a number of Canadian mining companies have invested in modern communications systems in order to automate processes and reduce operational costs. Safety of miners is also a concern, regulated by health and safety regimes.Underground communication systems rely mainly on analog technology (especially the leaky feeder). Digital upgrades have been made to modernize this technology using a coaxial or fibre optic cable to transmit voice, documents, commands, controls, and video. Therefore, all wired equipment can benefit from an increase in efficiency from the digital technology.However, when it comes to mobile equipment, the only medium was, and is, still radio waves. With the advent of the wireless local area network (WLAN) standard, one can use a technology similar to that of the cellular phone to connect transparently different equipment. WLAN enables the transmission at rates higher than 2 M bits of voice, documents, commands, controls, identification, and of course, digital video. This technology was developed with inbuilding use in mind. Now, one can try to adapt it to underground mines."

Jan 1, 2000

By M. Rantapaa

Measurable improvements in throughput have been documented at Barrick Goldstrike due to increased ore fragmentation through efficient drilling and blasting techniques. A decrease in throughput at the autoclave, due to increasingly hard ore, was identified in early 2002. A team of individuals from the open pit and process areas worked closely on the Drill-to-Mill (D2M) Continuous Improvement initiative to ensure that it would address the needs of both groups, with the target of actually improving throughput in future years, despite the projected harder ores. A series of tests were conducted to determine if adjustments to drilling and blasting could positively influence throughput. Better fragmentation and a subsequent increase in mill throughput were achieved through the use of electronic caps for more precision and flexibility, as well as for allowing extremely fast shots; explosives with a higher velocity of detonation (VOD) to provide for improved shock energy; and improved distribution of the explosives by decreasing pattern spacing. Early tests indicated a significant increase in throughput when processing identified harder ore. It is anticipated that the total process throughput (hard and soft ore) will increase by 6 tph in 2003 due to the improved fragmentation of the hard ore. Barrick Goldstrike?s D2M initiative includes roaster hard ore (BWI>17), as well as autoclave hard ore (BWI>15). Approximately 6 million tons of D2M material were shot in 2003, a relatively small amount compared to the 150 million tons to be mined. The benefit of additional ounces produced should far outweigh the additional drilling and blasting costs.

Jan 1, 2005

By R. Mckinstry, M. Rantapaa, T. Bolles

"Measurable improvements in throughput have been documented at Barrick Goldstrike due to increased ore fragmentation through efficient drilling and blasting techniques. A decrease in throughput at the autoclave, due to increasingly hard ore, was identified in early 2002. A team of individuals from the open pit and process areas worked closely on the Drill-to-Mill (D2M) Continuous Improvement initiative to ensure that it would address the needs of both groups, with the target of actually improving throughput in future years, despite the projected harder ores. A series of tests were conducted to determine if adjustments to drilling and blasting could positively influence throughput.Better fragmentation and a subsequent increase in mill throughput were achieved through the use of electronic caps for more precision and flexibility, as well as for allowing extremely fast shots; explosives with a higher velocity of detonation (VOD) to provide for improved shock energy; and improved distribution of the explosives by decreasing pattern spacing. Early tests indicated a significant increase in throughput when processing identified harder ore. It is anticipated that the total process throughput (hard and soft ore) will increase by 6 tph in 2003 due to the improved fragmentation of the hard ore.Barrick Goldstrike’s D2M initiative includes roaster hard ore (BWI>17), as well as autoclave hard ore (BWI>15). Approximately 6 million tons of D2M material were shot in 2003, a relatively small amount compared to the 150 million tons to be mined. The benefit of additional ounces produced should far outweigh the additional drilling and blasting costs."

Jan 1, 2005

By S. Kelebek, C. Gibson, M. Aghamirian

"Global niobium production is currently dominated by three operating mines, Araxá and Catalão in Brazil, and Niobec in Canada. Although over 90% of the world’s niobium is mined and processed in Brazil, a number of high grade niobium deposits exist worldwide. The advancement of these deposits depends largely on the development of operable beneficiation flowsheets. Pyrochlore, the primary niobium bearing mineral, is typically upgraded by flotation with amine collectors at acidic pH, and often includes a reverse gangue flotation stage prior to pyrochlore flotation. Challenges related to the flotation of niobium ores include complicated flowsheets which require pulp pH adjustment from alkaline to highly acidic conditions, difficulty recovering fine grained pyrochlore, producing concentrates that meet specifications, and minimizing the losses to reverse pre-flotation gangue concentrates, slimes, and tailings. The specific flotation challenges associated with different niobium ores are discussed. In some cases, the use of alternate flotation reagents and flowsheets are required to achieve reasonable gangue rejection and maximize recovery, particularly of very fine pyrochlore grains.INTRODUCTIONNiobium is a transition metal primarily found in the oxide minerals pyrochlore (Ca,Na)2Nb2O6(OH,F) and columbite (Fe,Mn)Nb2O6. After physical upgrading, pyrochlore is converted into a ferroniobium product which is largely used in the production of high strength low-alloy steel. Today’s niobium market is dominated by the Companhia Brasileira de Metalurgia e Mineração, whose Araxá operation produces over 80% of the world’s niobium. There are two smaller operations, Niobec in Canada, and Catalão in Brazil, which account for the remaining production (U.S. Geological Survey, 2013).A number of niobium deposits exist globally, their advancement dependent on the development of operable beneficiation flowsheets. Pyrochlore, the predominant niobium bearing mineral, is commonly upgraded by flotation with cationic amine collectors in acidic pulp conditions. However, many niobium ores do not respond to this typical flowsheet because they are either highly refractory or niobium deports to other minerals such as columbite, ilmenite and rutile, which are not as responsive to this reagent scheme (Bulatovic, 2010). Other reagents, such as alkyl hydroxamic acid, have been studied extensively and while promising, are not without their own inherent issues including lack of selectivity over iron oxide minerals, and high addition rates (Ni & Liu, 2012; Gorlovskii, Eropkiny, Koval, Strelstin, Khobotova, & Shtchukina, 1968; Gorlovskii, Khobatova, & Shtchukina, 1966).It is the aim of this report to highlight the challenges associated with the physical upgrading of niobium minerals through examination of the flotation behavior of two different ore systems. In order to overcome these challenges it is important to thoroughly understand the limitations of typical flowsheets/reagent schemes currently employed in operation."

Jan 1, 2015

By A. K. Croteau

"At Craigmont Mines Limited, Merritt, B.C., the mining practice of trackless sub-level caving was started in the latter part of 1966. This type of mining was new to the mine personnel and the mining industry of Canada as a whole. Sub-level caving has presented many old and a number of new problems in maintaining the equipment used in this method. This paper will deal with some of these problems as they affect this particular mining operation. It will be impossible to review all phases of the equipment, but an attempt will be made to cover the most pertinent aspects in maintaining the drilling, mucking and hauling, and auxiliary equipment."

Jan 1, 1970

By David Evans, David Barnes, Robert Raponi

"The Williams Mine processes, on average, 6,450 t/d of gold bearing ore using two parallel grinding circuits, leaching and C.1.P., carbon stripping, electrowinning and refining. At present, each grinding circuit consists of a SAG mill in closed circuit with a spiral classifier and a ball mill in closed circuit with two stages of cyclones.Since grinding has always constituted the largest portion of milling costs, the Williams Mine has been proactive in trying to reduce such costs through innovative changes. One project under consideration is the replacement of one spiral classifier by a vibrating screen.This paper discusses the testwork performed to evaluate the replacement of one spiral classifier by a vibrating screen, and the preliminary engineering performed to date.IntroductionThe Williams Mine, located in northwestern Ontario, approximately 40 kilometres east of Marathon, is part of the Hernia gold camp. The mine is operated by the Williams Operating Corporation and is owned by the Teck Corporation and Homestake Canada Incorporated. Operation of the mine started in October 1985 at a rate of 3,000 t/d. After a mill expansion in August 1988, throughput increased to 6,000 t/d. Production has increased steadily since the mill expansion and in 1995, an average of 6,450 t/d of ore was processed at a recovery of 95.1 %."

Jan 1, 1997

By C K. Bell, L. S. Collett

An AFMAG survey was flown in 1968 over the Upper Nelson River area, Manitoba. The flight direction was northwest-southeast and flight spacing was 2 miles. In the Cross Lake Subprovince, AFMAG showed that an isolated peridotite outcrop was part of a dike that extended over 80 miles. Diabase dikes are not always marked by an anomaly, but isolated cross-overs, when used in conjunction with geological and magnetic data, permit their extrapolation. Anomalies coincide with areas of sulphide mineralization. In the Flin Fion Subprovince, known and unknown northeast-trending faults are detected. The Berry Creek fault was extended south through Tramping lake, then under the Paleozoic cover. Conductors were detected at, or near, the axes of major synclines within Amisk and Snow Group sediments. Granitic terranes have low conductivity and, because they are characterized by smooth AFMAG profiles, they can be delimited. AF.MAG is being recognized as a geophysical method that can aid geological mapping and interpretation. Its most important contribution to the geologist will be in regions where out-crops are sparse.

Jan 1, 1971

By Eric Konigsmann

"The Pogo project is located on the Goodpaster River, 38 miles north of Delta Junction in east central Alaska. Sumitomo Metal Mining and Teck Corporation are planning to develop a 2,500 ton per day underground mine and mill at Pogo. A preliminary resource of 5.5 million ounces of gold has been identified in two flat lying lenses. An underground adit has been developed to facilitate underground drilling of the deposit and to provide samples for bench and pilot scale metallurgical testwork.Flowsheet development included the evaluation of several processing options. The final flowsheet selected includes SAGhall mill grinding, gravity concentration with intensive cyanidation and direct electrowinning, sulfide flotation with ultrafine regrinding, and cyanide leaching and CIP gold recovery from the flotation concentrates. Flotation tailings will be filtered for placement in a dry stack storage facility or disposed of as paste backfill underground. All of the CIP tailings will be disposed of underground as paste backfill. A pilot plant was carried out to evaluate the proposed flowsheet described above and to confirm the gravity recovery predictions.Great care was taken in the development of the flowsheet and site layout concepts to mitigate the environmental impact of the proposed operation. An overview of the site water management concepts is presented and the impact of water issues on the process flowsheet is discussed."

Jan 1, 2002

By R. D. Lindsay

Pamour Porcupine Mines, Limited has been actively engaged in the ''Custom Tolling'' of Gold-Bearing materials throughout the past decade. Experience acquired in this area was utilized to design and commission a custom gold milling facility at its operations in Timmins, capable of:(a) Accepting a bulk ore test sample at the rate of 150 t/d for crushing, sampling, and metals analysis;(b) Processing gold-bearing ores at a rated capacity of 150 t/d, to produce a goldbearing sulphide concentrate;(c) Processing free milling gold ores at a rated capacity of 80 t/d for total cyanidation;(d) Cyaniding custom gold flotation concentrates at a rated capacity of 80 t/d; and(e) Processing of complex gold/copper or carbonaceous ores, requiring an impurity flotation concentrate separation stage prior to cyanidation, at a rated capacity of 100 t/d.Items considered in the process design and development included:- various gold ore types available for processing;- flowsheet flexibility required;- sampling strategy as related to head grade determination and metals accounting; and- contract considerations.This paper highlights how these various considerations were used to design Pamour's ''Custom Gold Milling Facility''.

Jan 1, 1987

By S. Nikolic, G. M. Stieper, D. P. Mallah, B. J. Hogg, P. B. Voigt

Copper feed materials processing is becoming more challenging, due to an incremental increase in the mineralogical and compositional complexity of these feeds. These complex and polymetallic feeds are now becoming more common and many sites have been forced to re-evaluate their operating strategies to process these materials at cost competitive rates, whilst meeting ever more stringent environmental regulations. Most operations must first evaluate the merits of pyrometallurgical and hydrometallurgical treatment routes. Although there are multiple copper smelting technologies available, only top-submerged lance (TSL) technology, supplied by Glencore Technology as ISASMELT™, has been applied in the real world to consistently and successfully smelt complex materials in integrated metallurgical facilities such as Glencore’s Kazzinc Ltd. operation in Kazakhstan, Umicore Precious Metals Refining in Belgium and Aurubis AG in Germany. Glencore Technology also offers hydrometallurgical processing, through the Albion Process™ technology, opening up viable flowsheet options previously not possible for these complex feeds. This paper describes a number of real world process flowsheets at global operations and Glencore’s own operations at Mount Isa and Kazzinc Ltd., which process complex feeds. These flowsheets integrate the ISASMELT™, Albion Process™, ISACONVERT™, ISAKIDD™ Tank house, and bottom blown oxygen cupel (BBOC™) technologies to provide an effective process solution for the treatment of complex polymetallic feeds to produce metallic copper and associated by-products. INTRODUCTION Traditional smelters and those built in recent times within the bulk smelting hubs of the world have been designed to treat standard/clean concentrates. In recent years the processing of complex polymetallic sulfide concentrates and the recycling of secondary copper and derivatives of waste electrical and electronic equipment, such as e-scrap, have become a focus for numerous companies (Alvear & Nikolic, 2013). Processing of these complex feeds, characterized by relatively high levels of minor elements (over 5% of elements such as arsenic, antimony, bismuth, lead and zinc) is more challenging. Facilities not designed for these types of materials may require significant modifications or a change in smelting technology to treat them. Often operations find themselves re-evaluating the merits of pyrometallurgical and hydrometallurgical treatment routes for their sites through a number of factors:

Jan 1, 2019

By Robert D. Brown, Robert B. Parsons

"The mining industry may have survived the October 28 federal budget relatively unscathed, but the same certainly cannot be said of the petroleum sector-and many mining men are left wondering if their industry will be the next one to be singled out for special attention, as federal and provincial governments seek additional revenues and pursue nationalistic or provincial policies.Higher taxes, higher prices, a potpourri of ""incentives"", and a -""Canadianization"" policy mark the principal features of the new National Energy Program released by the government along with Finance Minister MacEachen's budget address.This month, Tax Notes examines the federal budget. with appropriate emphasis on the National Energy Program and its possible future implications forthe Canadian resource industries.IntroductionMost of the Canadian mining industry (tar sands miners excepted) heaved a sigh of relief on the evening of October 28, 1980, as Finance Minister MacEachen confounded the prophets in his budget address by not raising personal or corporation taxes and by making only relatively modest changes in the general tax system. Instead, he concentrated on a sweeping new energy policy. Unfortunately for that important sector of Canada's mining industry which is involved in mining the country's vast tar sands reserves, either now or in the future, the National Energy Program that was introduced along with the budget 'has serious implications."

Jan 1, 1981

By I. P. Barbosa, P. S. M. Soares, I. O. C. Masson

"Permanent magnets have been applied extensively to several electronic products such as printers, TV sets, microphones, microcomputers and headphones, presently manufactured in large scale by industrial economies. Sm-Co alloys represent about 20% of the world market for permanent magnets and their industrial processors generate 20-30% of magnetic scraps which can be recycled. This paper discusses a process route to recycle SmCo5 using acid treatment, solvent extraction of Sm and electrowinning of Co. The results confirm the feasibility of the alternative proposed. Basic operational variables are suggested as guidelines to design a plant for recycling magnetic scraps.The use of hydrometallurgical processes to recycle scraps from the industry of permanent magnets has been suggested in some recent papers related to recycling of metallic alloys [ 1 ]. These research efforts might be understood as a worldwide tendency towards the development of self sustainable metallurgical processes which mean the reduction of environmental impacts.CETEM -Center for Mineral Technology leads in Brazil several research programs concerning recycling and treatment of industrial residues. The work on samarium purification and concentration by solvent extraction, producing also a solution of cobalt sulfate as partially reported here is one of these programs. Previous results related to the sulfuric acid digestion of SmCo5 are presented somewhere else [2]"

Jan 1, 1997

By P. G. Killeen

Proper calibration of portable gammaray spectrometers and spectrometric logging equipment is essential if they are to be used for accurate quantitative determinations of radioelement concentrations. In the case of both types of equipment, it is necessary to determine the system calibration constants (stripping factors and sensitivities). In the case of borehole logging equipment, it is further necessary to determine the system response characteristics if the data are to be computer processed to improve the accuracy and resolution of the logs. Facilities are now available near Ottawa for the complete calibration of portable gamma-ray spectrometers and spectrometric logging equipment, in addition to already existing facilities for calibrating airborne gamma-ray spectrometers. Limited additional facilities are also available or planned in several other areas of Canada.

Jan 1, 1978

By L. Kilburn

A survey of 281 mineral exploration agreements examines the ratios among three ways that may be used to purchase an interest in a mineral property, viz: pay cash, pay shams and make future expenditures on the property. The dollar value of the future expenditures exceeds that of cash or shams by about nine times in most of the 110 agreements that contain cash-expenditure or share-expenditure components. Results suggest that cash and shams are treated about the same in terms of value. Buyers and sellers haw opposing priorities for the way that they prefer to purchase a mineral property. These opposing priorities should give rise to a perceived 50:50 balance between cash/share payment and future expenditures to satisfy the idealized situation described by most definitions of fair market value (FMV). This balance between cash/share payments and future expenditures appears to be rationalized in negotiations to a FMV when expenditures are nine times greater than cash and/or payments. On this basis, it is proposed that the FMV of a property may be determined by aggregating the dollar amount of the cash/share payments plus one-ninth the dollar value of future expenditures, as set forth in the respective purchase agreement, and proportionately applying such aggregate to full property value.

Nov 1, 2005