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By Jarrett. K. M.

Nobody has, as yet, made a perfect machine. Therefore, when a machine is operating and functioning as it is designed to do, there is always some vibration present. This is easily and simply measurable with present-day equipment and any increase in the amount of vibration will indicate a potential failure. When an increase is noted, vibration analysis can pinpoint the cause of the potential failure and remedial action can be taken before an unscheduled shutdown is necessary or a breakdown occurs.

Jan 1, 1972

By Barton G. Stone

The mining and exploration industries have been using Geostatistics (Matheron, 1963) for the past forty years. It has been extensively incorporated into three dimensional block modeling software whose usage has reflected the growth in the use of personal computers since 1980. Because of the utility of geostatistical models in mining and production planning, much of the modern reserve and resource modeling is done by mining engineers, geostatisticians and geological engineers. Explorationists are initially less concerned with three dimensional models until such time as a deposit has been roughly delineated. However, the concept of regionalized variables in ore deposits deals with the effect of spatial correlations between data points in a three dimensional sample space and should be useful for optimizing the spacing of drill holes to allow maximum bang-for-the-buck in drilling programs. This paper examines three common deposit types (porphyry copper, VMS and intrusive gold) to examine whether geostatistical methods have been used to minimize drilling costs because of better understanding of spatial correlations. The three model types were chosen from publicly available corporate websites of Canadian based Junior Mining Companies. They include the Wolverine polymetallic zinc deposit of Yukon Zinc in Yukon, Canada; the El Morro Deposit in Chile (30 percent ownership by New Gold Mining Company, and the Fort Knox Gold deposit in Alaska and 50 percent ownership by Nova Gold Resources). Typically, individual mining corporations post their technical reports as CNI 43-101 reports on their corporate website as indications of the favorability or progress on their more exciting properties. Data considered for this paper was not collected or generated by the author, but the information was extracted from these publicly available sites and had a variety of authorship.

Oct 1, 2009

By W. D. Robson

THE prevention of silicosis by metallic aluminium has been reported by Denny, Robson, and Irwin in two papers. The first (1) was published in 1937; the second (2), in 1939. The results definitely established that silicosis was prevented in animals by the inhalation of small quantities of aluminium. The present communication records subsequent progress in this field of research. HARMLESSNESS OF ALUMINIUM Animal experiments having served their purpose, it became necessary to consider means to test the discovery on humans. A question for immediate consideration was: Is aluminium harmful to man when inhaled as a fine powder? While the animal experiments were reassuring, since they conclusively showed the powder to be innocuous when breathed by animals, it was, nevertheless, desirable to have additional reassurance with regard to its effect upon human beings. Through the courtesy of the Aluminum Company of America and especially the valued interest in this problem displayed by that Company's Director of Research, Dr. Francis C. Frary, a study was made of the records pertaining to the health of a group of 125 employees who had for many years been engaged in the manufacture of finely powdered, metallic aluminium for the paint and ink industries. The conditions were such that these employees had inhaled varying and oft-times very dense concentrations of this powder daily over periods ranging from 6 to 23 years, the average for the group being 12 years. X-ray pictures of their chests showed no abnormalities attributable to aluminium. Their general health seemed better than that of the 3,000 workers in other sections of the plant. In fact, the early films of three employees in this group of 125 showed shadows suggestive of minimal tuberculosis, which shadows were not discernible in films taken after considerable periods of exposure to aluminium powder. The harmlessness of aluminium was, by this study, reasonably well established at the outset, a finding subsequently verified by Ontario research on humans.

Jan 1, 1944

By A. E. Cameron

The curve of coal production in Nova Scotia over the past forty years shows a definite maximum reached in 1913. Continued production to this maximum will require a greater tonnage per man-day, and this means there cannot be any increase in total man power used in the operations. There are still large reserves of coal but much of it will require washing or beneficiating to make a usable product. By-product recovery based on the present product ion is relatively satisfactory. Further development of secondary industries requires adequate markets for the bulk materials produced by the processing. It also requires access to other raw materials as well as markets for the principal product of the operations. Scientific investigation and research are needed to prove the quantity and value of lower grade or poorer quality coals, and methods for their recovery and utilization. Economics of further processing of present and future production must be investigated beforehand, if a successful development is to be assured. Such development cannot be expected largely to replace present markets. Production of coal for genera l use must continue to form the major function of the coal industry of the Province. Costs per ton must decrease, or subsidies or other assistance must increase, if the industry is to survive. Costs of investigation and research and costs of capital outlay for further development muse be met.

Jan 1, 1944

By P. T. Craddock, H. V. Paliwal, L. K. Gurjar

The Indian cultural heritage of mining, smelting and the use of minerals and metals dates back to ancient times. Although the exact date of the commencement of such activities in India is not certain, Indians are known to have been familiar with gold, silver, copper, tin and lead and to a lesser extent with iron at least since the Vedic period (Table 1).

Jan 1, 1999

By A. S. Bayne

THIS paper will present a review of the mining operations of one of Canada's most lately established gold mining districts (1). The history of the Little Long Lac and Sturgeon River areas is interesting in view of the fact that, although they have long been the scene of a certain amount of mining activity, they remained little more than an uninhabited wilderness until 1933, since which time ten producing gold mines and mills have been established in permanent operation, eight of these having entered production since the beginning of 1937. As complete a background as possible will be given concerning the major influences having a bearing upon living and economic conditions in the mining communities. The object, here, is to show the diversity of problems which demand the attention of the operator starting up and operating a new mine in present times, and to indicate the ways in which these problems are successfully met in this district. A description of the power facilities and plant equipment will be followed by a summary of the problems encountered and methods applied in exploration and development. This is to aid in forming a background showing the circumstances which influence the mining methods and costs of the various operations. The paper will conclude with a description of the mining methods used and the costs of the operations, including summarized analyses of the stoping methods and mining conditions. The various phases of operation will be dealt with separately, in so far as this is possible, in order to present clearly the salient features. It is necessary, however, that the reader bear completely and constantly in mind the fact that in actual operations these phases arc, to a large extent, intimately related and greatly affect each other, as well as being, in turn, affected by other circumstances beyond the control of the operator. A few of these circumstances are: capital available during the development period and early stages of productive operation; strength of rock comprising the ore and its boundary walls; grade, size, shape, and location of ore-bodies; and many other natural items which must be carefully weighed in relation to the details of operation.

Jan 1, 1940

By J. D. Bateman

DURING the summer of 1942 several chromite deposits were discovered in the Lac du Bonnet district about eighty miles northeast of Winnipeg. The deposits are confined to the Bird River complex, a folded composite sill of basic and ultrabasic igneous rocks of early Precambrian age that lies to the north of Bird river (1). The outcrop of the sill represents the trace of an easterly plunging anticline, the south limb extending from the northeast bay of Lac du Bonnet eastward to Bird lake, and the other limb, 6 to 12 miles north, lying between Maskwa river and Euclid lake. The south limb of the sill is 20 miles long, and the northern counterpart 15 miles; but its continuity is interrupted by faulting and by the intrusion of younger granite, so that the total length of outcrop of both limbs does not likely exceed 25 miles. The sill is intrusive into early Precambrian greenstones and associated sedimentary rocks. The chromite discoveries have been made at several localities on both limbs of the sill, and in each case at the same geological horizon. The sill comprises an upper layer of hornblende gabbro and a lower layer of serpentinized peridotite, and altogether is from 500 to 3,500 feet thick. The chromite zone is within and near the top of the peridotite layer, and thus about midway of the sill, both of the limbs of which stand nearly vertical. This geological relationship was established early in the exploration of the initial discoveries and served as the basis for successful predictions of later discoveries. The chromite zone probably persists throughout the length of the sill, but its width and chromite content are not everywhere the same. The initial exploration along both limbs of the sill has shown a combined total length of about 12,000 feet of chromite ore varying in width from 6 to 12 feet. In many places the overburden is thick and obscures the continuity of the chromite zone; but as investigation proceeds the known deposits will be extended and new ones will be found. Thus, although a total length of 12,000 feet of ore has been investigated up to the present time, there is an indicated length of approximately 31,000 feet along which the ore is more than 4 to 5 feet wide. This estimate is based on geological considerations and represents a total tonnage in the order of 15,000 tons per vertical foot of depth.

Jan 1, 1943

By D. C. Crothers

"What is new in air compressors? A good deal - the designers have been keeping pace with technical developments in related fields and also contributing new techniques of their own. Plant reliability no longer requires bulky slow-speed machines. Even the reciprocating machines, which still provide the most efficient method of compressing air, have been greatly reduced in size and installation cost for a given capacity rating. New materials and fabrication techniques are being used, by most manufacturers, to produce less costly plants in total. Many packaged plants are available, which generally means a more complete assembly for shipment. This type of construction offers savings in handling and erection costs at the site. A warning is in order, however - the extent of packaging in any given plant should be investigated carefully to determine what is included and just what field costs can be realized. A suggested specification has been offered for consideration when studying comparative costs. Rotating machines intrigue many because of their potential as regard fewer wearing parts, higher speeds and hence smaller units, utilizing less expensive drivers, and lack of contamination of the compressed air by lubricants. The inherent shortcomings of these machines - lower •efficiency and capacity control - have been much improved lately, and this type of plant is now becoming quite popular. Noise control, of much concern to everyone, is another development that has received considerable attention.Systems for efficient capacity control and continuous monitoring of compressor operation offer additional reliability and low-cost operation of the modern compressed air plant. Accessory equipment and its effect on over-all plant operation is also considered."

Jan 1, 1972

By Paul W. Billwiller

Introduction In 1937, the Britannia Mining and Smelting Company, Limited, was carrying on an extensive exploratory diamond-drilling programme. Most of this drilling was done on the 4100 level, the lowest working level in the mine. One of the exploratory diamond-drill holes, at approximately 12,500 feet from the portal of the tunnel, encountered heavily mineralized stringers of chalcopyrite and sphalerite in silicified grey schist. The mineralization was encountered just to the hanging-wall of the green mottled schist at a point 350 feet south of the 4100 tunnel. To delimit this new orebody, drifts and cross-cuts were driven on 3500, 3800, and 4100 levels to the hanging-wall in the area of the projected mineralization. On the 3500 level, the top of the mineralized zone was encountered. The zone was thoroughly explored by drifting and diamond drilling. The mineralization, however, was not sufficiently concentrated to be of commercial grade. On the 3800 level, the zone was found to consist of disconnected stringers of chalcopyrite and pyrite. Drifting was continued to the west and a long lens-shaped area of grey schist containing fairly heavy stringers of chalcopyrite was delimited. This lens later proved to be very close to the top of the commercial mineralization of the No. 8 orebody. On the 4100 level, a diagonal cross-cut was driven to the footwall of the downward projection of the mineralized zone. Diamond-drill holes from this cross-cut indicated a zone of heavy mineralization. A drift was driven off the cross-cut parallel to the zone and some distance to the footwall of it. Further diamond drilling disclosed a mineralized zone approximately 300 feet long and 35 feet wide containing sphalerite, chalcopyrite, and pyrite. The foregoing development work indicated a fairly large lens of mineralization of sufficient concentration to be classed as ore between the 4100 and 3800 levels. To explore this mineralization at depth, long diamond drill holes, dipping at minus 57° and minus 80°, were planned from some point to the hanging-wall of the orebody. The 4100 level was not suitable for small development headings, due to wider gauge track and larger cars than on the levels above. Therefore, a raise was driven from the diagonal cross-cut on the 4100 level to a point some 70 feet above and just inside the footwall of the orebody. From the top of the raise, drifts were expanded east and west to delimit the ore zone. In addition, a long cross-cut was driven 350 feet to the hanging-wall, and drifts were opened east and west from the end of the cross-cut to provide diamond-drill stations for the exploration of the orebody at depth.

Jan 1, 1946

By Deborah McCombe

"By now, most geologists and engineers in the Canadian mining industry are familiar with National Instrument 43101 Standards of Disclosure for Mineral Projects (NI 43-101) and the Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Definition Standards for Mineral Resources and Mineral Reserves, which are incorporated by reference in NI 43-101. In recent years, significant progress has also been made in establishing standard reporting practices internationally that recognize the globalization of the industry and enable investors to compare projects anywhere in the world and make informed investment decisions. This article is part of a series that will summarize the background and development of international resource and reserve reporting standards by the Committee for Mineral Reserves International Reporting Standards (CRIRSCO), highlight its current activities and provide insight into international mineral reserve and resource reporting issues. CRIRSCO was formerly the Mineral Definitions Working Group of the Council of Mining and Metallurgical Institutions (CMMI), an organization representing professional bodies in all of the major mining and mining investment countries. In 2002, CMMI disbanded and CRIRSCO continued as a volunteer committee with limited funding from those professional bodies and increasingly from other sources, such as mining companies and regulatory bodies. CRIRSCO was adopted as a Task Force of the International Council of Mining and Metals (ICMM) in 2007. The ICMM is an influential industry body representing all of the major mining companies and many junior companies through its associated members, such as the Minerals Council of Australia, the Chamber of Mines of South Africa and the Prospectors and Developers Association of Canada. CRIRSCO now has funding to pursue its objectives."

Jan 1, 2003

By Pierre Pelletier, Christian Pichetie, Dany Pelletier

"IntroductionDuring 1994, Barrick Gold Corporation, or American Barrick at that period, acquired Lac Minerals Ltd. properties. One of them was the Bousquet Complex. The Bousquet Complex is divided into three distinct sites: one mine (Bousquet 2), one mill (Est-Malartic Division) and one analytical chemistry laboratory (Les Terrains auriferes).The Bousquet 2 orebody was discovered in 1986. An extensive drilling program was initiated during 1987. Its purpose was to define the orebody extent. At the end of 1997, gold production from Bousquet 2 mine reached 1 290 000 oz of gold from a cumulative tonnage processed of 4 175 000 M t.From 1980 to 1990, the Est-Malartic mill was used for the treatment of ore from the following mines: Bousquet 1, Doyon, Francoeur (Richmont mines), Buckshot and 1-20 stope. At present, the mill receives ore from the Bousquet 2 mine.HistoryThe Est-Malartic mill is located close to the town of Malartic in northwestern Quebec. The mill has been in production since the mid-1930s processing mainly clean, free mill gold ore. Active mining from the Est-Malartic mine ceased in 1979 and the mill was switched to custom processing of ore from La Mine Doyon located some 45 km to the west. This custom processing arrangement continued until 1987 when the expanded mill at Doyon became available to process all of the Doyon production. In 1987, Lac Minerals commenced development of a second mine at the Bousquet site located 40 km west of Malartic. This mine, Bousquet 2, is the down dip extension of the La Ronde mine developed by Agnico Eagle. During pre-feasibility evaluations, it was determined that it would be economically more attractive to modify the existing Est-Malartic mill than building a new facility on site. The Est-Malartic mill modifications for processing the high-copper/gold ore from the Bousquet 2 mine began in late 1989 and new circuits were commissioned in mid-1990. Modifications included the addition of both gravity and flotation concentration circuits to recover coarse, free gold and the copper. The existing leaching circuit continued to operate on the copper flotation tailings with some minor modifications to the solution handling systems. A S02/Air cyanide destruction circuit was also added at that time."

Jan 1, 2000

By O. Matwijenko

"The Kidd Creek concentrator is located twenty-six kilometres east of Timmins, Ontario, within a metallurgical complex including a 109,000 MTPY zinc plant and a new 59,000 MTPY copper smelter and refinery. A complement of 159 persons is employed in the operation of the concentrator.Ore from the Kidd Creek Mine is crushed underground to minus 15. 0 cm, then transported twenty-seven kilometres by rail 1:0 the concentrator. After being crushed to minus 1. 6 cm, the ore is further processed by grinding and flotation.The concentrator commenced operations in November of 1966 at a designed capacity of 8,200 MTPD. Two parallel flotation and grinding circuits treated copper-zinc ore (2.28% Cu, 5.63% Zn) and a third treated silver-copper-lead-zinc ore (230 g/MT Ag; 0.57% Cu, 0.88% Pb, 7.89% Zn).By 1975, the concentrator was treating 9,100 MTPD of ore. Seven concentrates were being produced, namely, high silve1: copper, low silver copper, lead, low silver zinc, high silver zinc, pyrite and tin.Planned minesite expansion to a second underground mine required increased concentrator throughput. Expansion of the concentrator enabling a thirty-three percent increase in copper-zinc ore throughput occurred during the period 1975 through 1978. This expansion included increased load-in capacity, major redesign in the crusher house, the addition of a fourth grinding and flotation circuit, the building of a fourth dryer, and numerous expansions of services."

Jan 1, 1980

By Donald Leroux, Colin Hardie

"New or improved mathematical models of mineral processing machines are published almost on a monthly basis. Often, these models can be calibrated from bench-scale test results and programmed using spreadsheet software to simulate different designs and operating conditions in open-circuit configuration. However, since mineral processing plants frequently operate comminution, separation and/or extraction machines in closed-circuit configurations, open-circuit simulations often have limited applicability.The simulation of closed-circuit configurations necessitates the programming of an iterative loop to bring the circuit to equilibrium. This can be done by using spreadsheet software but often requires advanced programming skills. As an alternative, LIMN® software, which simplifies the programming of closed-circuit configurations within spreadsheets can be used. This software was specifically designed to turn a Microsoft EXCEL® spreadsheet into a closed-circuit modeling and simulation platform with minimal programming.During the past few years, the Mineral Processing Group at the Noranda Technology Centre, has used this software for numerous projects which include the simulation of multi-stage cyclone circuits, closed-circuit regrinding and locked-cycle flotation tests. Using these projects as examples, the flexibility and the easy to use nature of the LIMN® software is demonstrated.INTRODUCTIONMineral processing engineers routinely have to make predictions regarding comminution and separation processes. Predicting the appropriate dimensions of equipment and the process response to changes in operating mode are probably the most common situations that they face. In all cases these predictions are expected to be rapid and accurate.Predictions made by engineers are frequently based on mathematical models. Many first principles, empirical, semi-empirical, steady state and dynamic models of mineral processes can be found in the literature. In fact, new or improved mineral processing models are continuously being proposed and in spite of this variety, process engineers often have to either develop their own or tailor existing models to suit their particular needs."

Jan 1, 2003

By Biplop Das, E. Herrera, A. Burrows, P. J. Mackey, G. R. F. Alvear Flores

Since the first commercial plant was built at Mount Isa, another twenty ISASMELT™ furnaces have come into commercial operation, and construction of new plants continues. The primary copper ISASMELT™ top submerged lance (TSL) technology continues to attract interest from potential users who seek to smelt productively. In addition to the known benefits of productivity and flexibility, ISASMELT™ operators have also achieved improvements to energy efficiency when switching from their previous technologies. The recent production statistics for operation at Tuticorin, India show that ISASMELT™ has taken the first steps into territory beyond 400,000 t/y (copper cathode basis) and this will likely be the scale chosen by future new copper smelters operating purely on a toll smelting basis. Highly energy-efficient technologies will be expected at these smelters

Jan 1, 2015

By S. Nafisi

Permanent mould casting may be regarded as a near net shape manufacturing process where simple to very complex shaped engineering components are fabricated with high degree of precision in a metallic mould, In this group, High Pressure Die Casting (HPDC), have attracted more attention because of its production rate, where both liquid and semisolid metals (SSM) can be cast with high degree of precision and versatility. The SEED process, Swirled Enthalpy Equilibration Device, the new process for semi solid metals slurry production route, consists of two steps: The initial step involves extracting specified amount of heat from the molten metal to generate liquid-solid slurry, i.e, mushy structure, followed by drainage of remaining liquid to produce a compact free standing feedstock for rheocasting operation. In this paper, microstructural evolution during the process and some initial casting results of automotive components an also reported.

Jan 1, 2005

By Mory Ghomshei

As fossil fuels become depleted over the next century, it is imperative that Canada and other countries examine ways to transition to other sources of energy, particularly renewable resources. A critical obstacle to developing Canada?s renewable energy resources is the scarcity of infrastructure to wheel the generated electricity to a viable market. For each megawatt of renewable electrical power, a maximum of 1 km of connecting power line is typically feasible. This means that hydropower, geothermal, and wind power projects with capacities up to 100 MW must be located within a maximum of 100 km of a main power line in order to be economically viable. With a total length of about 1200 km, the proposed Northern Gateway oil pipeline project creates an excellent opportunity to become a corridor that can seed renewable energy projects in Northern British Columbia and Alberta. Utility companies must build new infrastructure to provide the electricity for constructing and operating the proposed pipeline. The pipeline and linked power line infrastructure therefore, should be designed and built with consideration to create an energy highway to the significant renewable energy resources, such as hydro, wind, and geothermal, in the vicinity of the proposed pipeline. Some of the important renewable energy resources in northern British Columbia can be developed in connection with the proposed pipeline. It is estimated that close to 2,500 MW of commercially viable wind, geothermal and run-of-river power resources are present in the proximity of the proposed pipeline corridor. While oil flows westward from the Alberta bitumen fields, the generated green power can flow eastward to help the Canadian oil sand industry to offset as much as 10 Megatons of carbon emissions per year. The generated carbon credits are equivalent to 75% of the emissions associated with extraction of the 525,000 barrels per day of oil from oil sands, intended to be carried by the pipeline.

Aug 1, 2013

By Changping Hu, Keqin Tan

In 1937, the Metallurgical Department of the National Resources Committee established a copper refinery plant (predecessor of the Chongqing Smelter) in Changsha, Hunan Province, China. The blister copper produced by a local copper smelter was casted as anode for electrorefining. The plant, with a capacity of one ton of electrolytic copper per day, was designed and tested in 1937. At the trial production stage, a total of 9 tons of cathode copper was produced. The plant was formally put into operation in July 1938. In the same month, more than 20 tons of electrolytic copper with purity over 99.9%Cu was produced. This was the first batch of electrolytic copper produced in China. In 1939, China’s largest non-ferrous metal smelting plant, Fengtian Gold Mine Refining (predecessor of the Shenyang smelter) was completed and put into operation in Shenyang, mainly producing nonferrous metals such as gold and silver, as well as copper and lead. In 1939, the Kunming copper smelter (predecessor of Yunnan Smelter) was completed and put into operation. The plant equipment, imported from the United Kingdom, was designed to produce 1,200 tons of electrolytic copper annually. In 1943, Jiatong smelter (predecessor of the Shanghai Smelter) became the 4th domestic cathode copper producer. Since 1949, China has gradually established a large copper industry. These developments are discussed in this paper. Today, China operates nine out of the twenty largest copper refineries in the world. With a total capacity approaching 9 million tons of copper per year, China has the world’s largest copper refining capacity. INTRODUCTION China is a country with a long history of copper mining. The earliest smelter in China in recent times was the Shanghai Smelter, which was built in 1912. From then until 1949, China successively built Chongqing Smelter, Kunming Smelter and Shenyang Smelter. The world's first copper electrorefinery was the Pembrey refinery built in the UK in 1869 (Lu, 1999). However, it was not until 69 years later that the technology was spread to Changsha, China.

Jan 1, 2019

By C. Han, S. J. Zhou, Y. B. Shen, D. Z. Wei, P. Fang

"Collecting property of two hydroxamic acid collectors have different type of nonpolar structure to hemimorphite has been comparatively studied via monomineral flotation test, and the reason causes different collecting performance has been discussed from the view of relationship between molecular structure and collecting property. The flotation tests results show that C5-9 hydroxamic acid has an unbranched linear alkyl nonpolar group shows better collecting property to hemimorphite than cyclohexyl hydroxamic acid which has a naphthenic nonpolar group. FTIR detecting results show that the adsorption type of collector adsorbed on hemimorphite surface is chemical adsorption. Calculation results of polar group’s geometric structure parameters, polar group’s electron density distribution, octanol-water partition coefficient (logP) and molecular frontier orbital energy show that the key factor caused different collecting property of two collectors to hemimorphite is the logP; unbranched linear alkyl nonpolar group is more conducive than naphthenic nonpolar group to make hemimorphite particle more hydrophobic.INTRODUCTIONZinc-bearing mineral recovered from lead-zinc ores is the main source that people can obtain zinc resource from nature. However, natural sulfide ores are currently getting depleted steadily for the primary zinc source. In order to satisfy the future demand of zinc resource, there is an obvious recognition that the recovery of zinc oxidized minerals from the ores is a crucial alternative (Hosseini & Forssberg, 2007; Navidi Kashani & Rashchi, 2008).But the fact that can’t be ignored is the flotation of zinc oxidized minerals is much more difficult than that of zinc sulfide minerals, which is mainly due to the flotation characteristics of these zinc oxidized minerals such as lower selectivity and higher reagent consumption, as well as complex and variety of lead-zinc ores. Presently, there have been many various beneficiation technologies used for recovering zinc oxidized minerals and dealing with ores for recovering metallic zinc such as flotation and hydrometallurgy (Abkhoshk, Jorjani, Al-Harahsheh, Rashchi, & Naazeri, 2014; Önal et al., 2005). But from an overall perspective, flotation is the most common method used for the beneficiation of zinc oxidized minerals, and there have been extensive investigations conducted on the flotation of zinc oxide ores (Ejtemaei, Gharabaghi, & Irannajad, 2014). Until now, the most well-known method used commercially for the flotation of zinc oxidized minerals is sulfidization with sodium sulfide and flotation with a cationic collector of amines containing from 8 to 18 carbon atoms. However, a major problem for this method is the large amount of fines and slime results in the increase of reagent consumption and promotes the phenomenon of slime-coating. For preclude this negative effect, the de-sliming and processing optimization is indispensible (Peres, Borges, & Galery, 1994; Salum, de Araujo, & Peres, 1992)."

Jan 1, 2016

By J. Dong

"Xanthate is a sulfide collector that has been widely used in flotation for almost a century. It is inexpensive, easy to synthesize and apply, and produces good metallurgy in the right applications. However, a major drawback of xanthate is that it decomposes easily and generates CS2 gas in transportation, storage and operation, which can be harmful to human health. Also, excessive xanthate in tailings pond leads to toxicity of the process water and potential damages to aqua-life systems. New regulations in Ontario require that the TWA (time-weighted-average) value of CS2 in the work place is below 1 ppm, which is 1/10 of the previous limit. The stringent regulation may eventually sweep other regions of Canada with the increased awareness of healthy working conditions and environment protection. Therefore, it becomes very important to find xanthate replacements which will be “green”, i.e., environmentally friendly.In this research work, a systematic procedure is used for collector evaluation using the Sudbury nickel sulfide ores from Vale’s Ontario operations, starting with the collector properties (MSDS) evaluation, followed by batch flotation tests, miniplant tests, plant trials and economic evaluation. It is found that the most promising xanthate replacement is dithiocarbamate.INTRODUCTIONSulfide mineral flotation has been practiced since the early 20th century. Its industrial importance is well recognized as mineral concentrates from flotation can be economically smelted and refined to provide primary metals. Collectors play a vital role in froth flotation. There are reagents possessing both a polar group that binds them to the mineral surface and a nonpolar group that is oriented away from the surface to attach air bubbles. The introduction of xanthate as a sulfide collector in 1925 was a remarkable development in froth flotation (Keller, 1925). It is low cost, easy to synthesize, water soluble, simple to control in application. Most importantly, it has strong capability and usually good selectivity for sulfide mineral flotation, which have been keeping its application prominent for almost a century."

Jan 1, 2011

By E. De Souza

Two comprehensive surveys, which focus upon backfill practices and the economics of backfilling in underground mines in Canada, have been conducted. The two surveys were designed to assess operational practices and costs associated with the wide scope of filling operations that must be met by individual mines, ranging from raw material feed to the preparation plant, through underground backfill transportation, to in-stope product placement. This paper presents the current state of backfill usage in Canada, identifies trends in minefill practices and provides mine operators with an updated database of information upon which they might compare their own practices and costs with present trends throughout the industry.

May 1, 2003