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By K. Adham, C. Lee

The demand for nickel is continuing to exceed inventories, and producers are working vigorously to increase capacity. Many nickel processes utilize the fluidized bed technology for its fast heat and mass transfer, excellent temperature control and low maintenance. The following four nickel applications of the fluidized bed technology have been commercialized: I) Sulfide ore roasting; II) Nickel sulfide (matte) roasting; III) Nickel oxide reduction; IV) Nickel chloride pyrohydrolysis. This paper examines the issues surrounding the application of fluidization technology to the above processes, from the stand point of the engineer modeling the process and designing the key equipment, based on the historical success stories and the fundamental principles of flow sheet synthesis. Using the available data in open literature, typical flow diagrams (with convenient bases of 1 t/h feed or product) are developed to illustrate the relative flow rates and to highlight the key features of each application. In addition, some historical background information is provided for each process with supplemental notes with regards to our company's involvements.

Jan 1, 2005

By J. Hoover

"IntroductionThis chapter will discuss the operational and maintenance aspects of a heavy media cyclone circuits as applied to coal processing and using magnetite as the media. It deals with heavy media bath separators in terms of types of media, equipment, circuits, media recovery, maintenance, and product handling. It will detail heavy media cyclone operation and supplement the previously described topics.The heavy media cyclone was first developed in the Netherlands by the Dutch State Mines in 1945. A cyclone plant was not built in North America until 1961. Traditionally, heavy media cyclones have been used to treat size fractions between 1lz in. (12 .6 mm) and 35 mesh (0.5 mm). High maintenance related to heavy media bath separators has recently prompted some plants to crush all raw coal to minus 2 in. for treatment in heavy media cyclones.The heavy media bath separators utilize only the force of gravity to make the separation between heavy and light particles. This requires lengthy retention time which can lower capacity and also is inefficient for finer particles. A heavy media cyclone utilizes centrifugal forces which are 20 to 200 times greater than the force of gravity. This means the separation between coal and the impurities occurs very quickly, therefore a low retention time is required allowing cyclones to have high tonnage capacities. Also these greater forces allow better separation for the finer particle sizes.Heavy media cyclones are now widely used to produce both metallurgical and thermal coal. Work is in progress to reduce magnetite consumption, extend wear life, increase tonnage capacity, improve separation efficiency and automatically control these cyclone circuits."

Jan 1, 1989

By Helmut Lerchs

An open-pit mining operation can be viewed as a process by which the open surface of a mine is continuously deformed. The planning of a mining program involves the design of the final shape of this open surface. The approach developed in this paper is based on the following assumptions: 1. the type of material its mine value and its extraction cost is given for each point; 2. restrictions on the geometry of the pit are specified (surface boundaries and maximum allowable wall slopes); 3. The objective is to maximize total profit-total mine value of material extracted minus total extraction cost. Two numeric methods are proposed: A simple dynamic programming algorithm for the two-dimensional pit (or a single vertical section of a mine), and. a more elaborate graph algorithm for the general three-dimensional pit. ASURFACE mining program is a complex operation that may extend over many years, and Involve huge capital expenditures and risk. Before undertaking such an operation, it must be known what ore there is to be mined

Jan 1, 1965

By M. Fall

The progressive depletion of ore available at shallow depths in several underground mines around the world means that underground mining operations would increasingly be carried out at greater depths and therefore at higher temperatures. However, our understanding of the effect of hot temperatures on the response (mechanical, economical, environmental) of cemented paste backfill (CPB) is still limited. Hence, an extensive laboratory investigation was conducted to study the performance of young and aged CPB, in response to deep mine temperatures. Several CPB samples with different compositions, cured at different temperatures (20 to 50°C) and different times (7 to 160 days) were tested regarding their mechanical properties, economical performance (binder consumption) and microstructural properties. The results show that hot temperatures significantly affect the performance properties of CPB at young and advanced ages. An increase in the curing temperature leads to a considerable improvement of the rate of gain of CPB strength and also to a significant increase of the strength of CPBs studied. CBP samples cured at hot temperatures show lower binder consumption and finer pore structure. Results of this study could serve as background information for the development of optimal mine backfill design procedures.

May 1, 2007

By Brian Putland

Single stage semi-autogenous / autogenous (S/AG) milling has become a common design for a variety of ore types with the advantages of being comparatively low capital cost and flexible for future expansion. The single stage SAG/AG milling option is ideal for starter projects with significant exploration and expansion potential. Currently a number of the largest SAG mills designed are installed in single stage configuration. This paper discusses the challenges associated with the process design of single stage SAG/AG milling circuits, the design flexibility required to ensure a robust circuit and the operating techniques adopted at successful installations.

Jan 1, 2012

By A. Saigal

The effect of temperature on the cutting forces during machining of alumina reinforced aluminum composites was investigated, Aluminum 6061, 10% Al2O3 reinforced composite and 20% Al2O3 reinforced composite were tested, A 5/8-inch diameter high-speed steel end mill, a Micro 100 TiN coated single edge endmill cutter and a two-fluted solid carbide insert cutter were used for tooling, The results, in general, showed an increase in the cutting forces as the temperature of the material increased, From the raw data, there are temperatures ranges in which the force data did decrease but they were insignificant with regards to predicting a downward trend. A regression analysis was used to understand which variables had the greatest affect on the forces being generated, The correlation and regression analysis showed that at 600 rpm (velocity: HSS- 98,2 sfpm, Micro 100 cutter - 78,5 sfpm, solid carbide cutter - 192,4 sfpm) the tooling, the workpiece material, built up edge, and temperature were statistically significant factors in the test, Tooling was a significant variable in all testing, The smallest forces recorded during machining were generated with the solid carbide two-fluted endmill cutter, Visually, the solid carbide tooling produced a better surface finish during the testing which made it the tool of choice, In addition, the force data proved that as the cutting speeds were increased, the cutting forces decreased.

Jan 1, 2005

By J. H. Ambrose

Introduction The copper smelter of the Hudson Bay Mining and Smelting Company, Limited was constructed to handle the concentrates produced by the concentrator, the residues from the zinc plant, concentrates from Sherritt-Gordon Mines, Limited, and other custom material that might be available. Construction work was started in 1929 and the first concentrates were smelted in November, 1930. From that time until June, 1931, the operations were more or less of an experimental or tuning-up nature. In designing the smelter, it was believed the following tonnages would be available for smelting per day: Copper Tons Content H. B. M. & S. Co. concentrates 331 14.0 per cent H. B. M. & S. Co. zinc plant residues 77 2.5 per cent Sherritt-Gordon concentrates 200 20.0+ per cent Consideration was given to wet-smelting the charge, but, in order to give greater flexibility to the operation, it was finally decided to roast the concentrates before smelting. Briefly, the smelter equipment consists of three Nichols-Herreshoff roasters, one reverberatory furnace, two Peirce-Smith converters, a Walker casting wheel, and a four-unit Cottrell plant, two units' for the roaster gases and two for the converter gases. A general plan of the smelter is shown in Figure 1. Prior to the commencement of smelter operations, a stockpile of about 9,000 tons of concentrates had been built up by the concentrator and the old pilot-mill. The zinc plant was in operation, but the equipment for drying the residues at the smelter had not been completed. Sherritt-Gordon did not commence their shipments of concentrates until April, 1931. The only flux available was barren sand from a pit ten miles south of Flin Flon, adjacent to the railway. Several small deposits of metal-bearing siliceous ore had been discovered in the district, but none of these were sufficiently large to be considered as a source of smelter flux. At the beginning of March, 1931, the entire stockpile of concentrates had been consumed, and available tonnage for smelting was limited to the daily production of the concentrator.

Jan 1, 1935

By E. G. Gaylord

THE material improvements which have been made in the practice of exploiting oil and gas reservoirs in the United States during recent years may be attributed largely to: (1) The necessity for drilling deeper wells at costs not much greater than was formerly expended on shallower wells. (2) The necessity for producing oil at a lower cost per barrel. (3) A growing recognition of the importance of the nature of production practice upon ultimate yield of oil and gas. The first two of these factors result, to a large extent, from the fact that a greater proportion of new development has been deeper development, and these wells have been drilled in the face of progressively lower per well allowables. In California, for instance, maximum allowables have declined from 400 barrels per day in March, 1938, to 156 barrels per day in September, 1940, and during this same period some 125 wells were drilled to the deeper 10,000-foot producing horizons discovered during this time. The third item listed above results from our increasing knowledge of the basic factors which influence the amount of recovery we may expect from reservoirs. In addition to the longer-range planning now being undertaken by the more prudent operators, State proration and conservation laws have focused attention upon the importance of methods conducive to obtaining progressively greater quantities of the hydrocarbons in place. In a paper of this length it will be possible to discuss only a few of the recent advances. An effort has been made to select the more important of these and to indicate, where possible, the factors which have made these advances possible.

Jan 1, 1941

By James R. Hein

Manganese nodules form at the sediment surface of abyssal plains throughout the global ocean at water depths of about 4000-6500 m. The nodules form a continuum from purely hydrogenetic (all metals from seawater) to purely diagenetic (all metals from sediment pore waters), which will determine which metals of potential economic interest are enriched in the nodules. Another important factor in metal enrichment is whether diagenesis in the bottom sediment is oxic or suboxic. There are several nodule fields in the deep ocean that have received much attention with regards to economic potential, the most important being the Clarion-Clipperton zone (CCZ) in the NE Pacific, where the International Seabed Authority (ISA) has signed 12 contracts for exploration areas, each spanning 75,000 square kilometers. Those nodules are rich in nickel (mean 1.3 wt. %), copper (mean 1.1 %), and manganese (28%), with moderate amounts of cobalt (mean 0.2%), molybdenum (587 g/t), and lithium (129 g/t). A conservative estimate is that there exists 21,100 million dry tonnes of nodules in the CCZ, yielding more manganese, twice the nickel, three times the cobalt, and four times the yttrium than the entire land-based reserve base (economic plus marginally economic plus subeconomic reserves) for each metal. Total rare-earth elements (REEs) as oxides average 0.09% in CCZ nodules, a potential byproduct even at that grade because the heavy REE complement averages 26%, compared to less than 1% for the large land-based carbonatite REE deposits. The price for HREEs is much greater than for the light REEs. For comparison, the REEs in deep-ocean ferromanganese crusts are 3 to 5 times greater than nodules and the HREE complement averages 18%. Of the 12 CCZ contracts, 7 are with States (China, France, Germany, Japan, Korea, Russia, and a group of States (IOM); and 5 are with companies: G-Tec Sea Mineral Resources NV, Nauru Ocean Resources Inc. (NORI); Tonga Offshore Mining Ltd (TOML), UK Seabed Resources Ltd (Lockheed UK), and Marawa Research and Exploration Ltd. Three other nodule fields that have received attention are in the Peru Basin, which has nodules very rich in manganese (34%) and lithium (mean 311 g/t), the Penrhyn Basin (Cook Islands Exclusive Economic Zone), with nodules very rich in cobalt (mean 0.4%); and the Central Indian Ocean Basin (CIOB), where India has an exploration contract with the ISA. CIPB nodules have mean nickel, copper, and manganese contents of 1.1%, 1.0%, and 24% respectively.

May 1, 2013

By Arthur. H. Winckers, Stephan L. Chryssoulis

"The deportment of gold in residue samples of cyanide leach tests of David Bell ore from level 6A block 13 was established using a comprehensive quantitative mineralogical approach. In every test the feed was first pre-aerated for 4 hours, followed by 48h cyanidation. Test no. 2 was done without lead nitrate and yielded a residue assaying 3.03g Au/t. In test nos. 4 and 9 lead nitrate was added before pre-aeration at 0.03kg/t and 0.3kg/t respectively yielding residues of 1.04 and 0.81 g Au/t.The mineralogical approach employed to establish the deportment of gold involved superpanning, to preconcentrate the free gold and assaying of the tailing fraction to determine the gold associated with quartz. It was thus determined that without lead nitrate added 47.2% of the lost gold is in the form of residual free gold particles less than 20 µm in size. It is this form of gold which is under represented in the residues of leach tests with lead nitrate added.Having eliminated coarseness of gold particles as a factor for lower recovery, it was determined that the residual gold particles have extensively contaminated surfaces. Amongst the deleterious surface contaminants identified: S, As, Ag, Sb and Hg, the two most harmful are S and Hg because of their concentration on the surface and rate of accumulation.Mercury and Ag are minor constituents of native gold at David Bell (average composition Au: 78.9 wt%, Hg: 18.5 wt% and Ag: 2.6 wt%) and they become enriched on the surface of residual gold particles because of their slower rate of dissolution in cyanide. The other elements absorb onto the gold particles from solution.The beneficial effect of lead nitrate was documented by comparative surface analysis of gold from residue samples of 48 hour leach testing with and without lead nitrate added and from time dependent (0-2 hour) leach tests in the presence and absence of lead nitrate. Lead nitrate accelerates the dissolution of gold by performing the following functions: (i) catalytic effect on the cyanidation of gold by accepting electrons; (ii) reaction with surface sulphur to form PbS which is then removed by oxidation; (iii) catalytic reaction on amalgam and Ag facilitating the cyanidation of Hg and Ag thus slowing down their build up onto the dissolving gold particles and (iv) the precipitation of sulphide sulphur from solution thus minimizing its build up on the surface of dissolving gold particles which is believed to facilitate the access of cyanide ions."

Jan 1, 1996

By Alan S. Lock

Large scale feasibility studies for the establishment of oil-seed and cellulose producing crops on mine tailings have been successfully conducted over 1 growing season with the purpose of these crops to be used as feedstock to the biofuels industry. An acid sulphide tailings impoundment in Copper Cliff, Ontario and a near neutral pH goldmine tailings impoundment in Timmins, Ontario were both tested by amending half hectare plots to approximately 1 m thick with residual biosolids from the pulp and paper industry and growing canola and corn on these plots. Full scale agricultural equipment was used to cultivate seed and harvest the plots to prove the full scale feasibility of farming on these biosolids. The vegetation development, growth, yield, quality and composition were assessed to identify the best species that would maximize biomass development for feedstock to the biofuels industry and carbon credits for the mining industry. Groundwater, biosolids and tailings chemistries were investigated to identify potential deleterious impacts of degrading organic matter on tailings metal mobility. Preliminary hydrologic investigations using moisture sensor profiles elucidate potential conservation of water in amended plots. Tailings amended with biosolids have the potential to provide the mining industry with carbon credits and supply feedstock to this new industry while reclaiming brownfields to a new level, utilizing industrial and municipal organic waste material.

May 1, 2009

By Rebecca L. Jones

The paper addresses the application of XPAC AutoScheduler at the Fort Hills Energy Oil Sands Project to complete fast turn around ?what if? scenario testing of different mine schedules. Traditional scheduling approaches involve engineers making a ?best guess? at the required mining sequence, loading this sequence into a scheduling package and testing the results to determine if the schedule meets corporate objectives. This process is iterative and can be very time consuming. Autoscheduling techniques, on the other hand, are based on the engineer pre defining the mining rules and constraints of the deposit. The software then automatically selects a sequence of mining which the schedule should try and achieve, based off specified corporate objectives. Under this system the engineer is able to adjust the objectives and rules to evaluate numerous scheduling scenarios quickly and easily. An XPAC AutoScheduler model was built, documented, and implemented by Runge and Petro-Canada Oil Sands Inc. personnel in a month. It is currently being used by Petro-Canada Oil Sands Inc. to run multiple schedule scenarios, most taking less than ten minutes configure and ten minutes to schedule. The results of each schedule are tabulated with supporting graphs on; the bitumen grade profile, strip ratio, ore inventories and mined tonnage. In addition to this, the block model may be animated to show the progression of the resources mining the schedules.

May 1, 2008

By Gil Espejo, Denise Duncan

"In Alberta, several initiatives are under way to form partnerships between educators and industry to work together in preparing a skilled and technically competent workforce for the future. One successful initiative is the Teachers in Business program which provides high school teachers one month paid internships in Alberta businesses. Initiated by the Science Alberta Foundation in 1992, this program has offered participating teachers a variety of work experiences and job shadowing tours in industry.A Growing Need of Education and Industry PartnershipsIn our ever evolving world, industry is in a tight race to keep up to date with new technology and to remain competitive. Industry is relying on the education system to provide them with the core base for their future workforce. To accomplish this, the education system needs the support of industry to develop the right focus to prepare its students for the race. What skills will our future workforce need? How can we best prepare our students for these needs?Teaching the latest in technology, especially at the high school level, is a major challenge. It is difficult for educators to keep abreast of the rapid changes in technology. High school graduates need exposure to the latest advancements. And so do their teachers. Students must be prepared to adapt to the challenges of the future, Le. global competition, rapid technological change and an expanding knowledge base."

Jan 1, 1995

By M. H. Rana

"A survey of our knowledge in the field of rock mechanics is presented from the viewpoint of applications in the mining industry. Aspects of rock mechanics of special interest to the industry are enlarged upon, with emphasis on the avoidance of over-generalization. The relationship between fundamental and practical rock mechanics is discussed, and the need for cooperation between the university and industry to further our knowledge of -useful rock mechanics is emphasized. An attempt has been made to establish the scope of rock mechanics, as applied to problems in the mining industry. This is brought about by projecting rock mechanics as a tool to be intelligently used rather than magic, capable of producing ""miracles."" Continued education is important for individuals engaged in the application 0f rock mechanics in the mining industry. The scope of this education is discussed from a viewpoint of better communication between industry and the education and/or re-search establishments engaged in this work.Finally, the dangers of over-emphasis on rock mechanics are mentioned, but a justification of the in-vestment in rock mechanics programs in mines is also presented."

Jan 1, 1966

By C. O. Staples, J. G. Morrow

The application of cationic flotation to the upgrading of magnetic concentrates was investigated in the laboratory by both batch and continuous test procedures. It was found that the collection of coarse gangue particles with amine, heretofore considered a serious obstacle to this particular application of cationic flotation, is greatly enhanced by a drastic reduction in what might otherwise be considered normal impeller speed. Gangue flotation is in-dependent of variations in the rate of aeration. The collector and Crother additions and the impeller speed which favour the formation of a matte froth yield optimum results.

Jan 1, 1966

In this study, flotation of fine galena, chalcopyrite and pyrite was performed after grinding with different extent of oxidation-reduction condition adjusted by grinding media. Sodium dithionite and iron ions were added in mill to simulate pulp potentials and iron oxidation species produced by grinding media, respectively. The types and quantities of the metal oxidation species on mineral surfaces were determined by EDTA extractions, while the surface electrical properties of minerals and interaction of different types of metal oxidation species were studied by zeta potential measurements. It was found that the nature and concentration of the absorbed metal oxidation species were dependent on oxidation atmosphere controlled by the iron amount of grinding media. These species interacted with each other and had an important role in determining flotation of fine galena and chalcopyrite as well as activation of fine pyrite by lead and copper.

Jan 1, 2006

By J. Malone, D. Loth, J. Palmer

WMC Resources' Kalgoorlie Nickel Smelter was commissioned in 1972 at a design capacity of 30,000 tpa of contained Nickel in matte. A series of upgrades and progressive improvements have resulted in a design capacity increase to 110,000 tpa of contained Nickel in matte. The smelter sources nickel-in-concentrate from three Mine / Concentrators and supplies nickel-in-matte to WMC's Nickel Refinery and export customers. The Flash Furnace was last rebuilt in 1999, and is over halfway through the 10-year campaign target. The many modifications over the previous campaigns, including the Integrated Flash Furnace, are reviewed. Recent operation of the smelter and the development of the process during the current campaign are detailed herein. An overview of key interfaces with the Nickel Business Unit Concentrators and Refinery operations is provided.

Jan 1, 2005

By Christian Brits, Bob Blain, Lloyd Buckingham, Juliu Stieger, Jean-Francoi Dupont

Barrick Gold Corporation (Barrick) has undertaken innovative methods of evaluating and improving the performance of grinding mills in several of its operations around the world. The results have been positive with some of the mines showing more than 20% net energy improvement leading to more than 43,000 tonnes per year reduction in CO2 emissions in four of the operations reviewed.

Jan 1, 2012

Agenda ?The Context ?The Challenge ?The Solution ?Benefits and lessons learnt from pilots ?Next Steps The Context ?Facilitate management decision making process by supporting the development of value/risk based business cases. ?Large scale investments by extractive industries are expected tobring broad-based benefits to local communities (e.g.: health, education, jobs, infrastructure) ?Investors continue to expect the demonstration of social performance?Specific interventions bring direct value to companies (e.g. skills development) ?Social Investments are key to protecting a company?s license to operate ?Quantifying the value of these investments and planning accordingly, however, has long posed a challenge for the extractive industries and community development practitioners

May 1, 2011

By J. Basi, J. A. Finch

ABSTRACT Testing the effects of bubble size (Db) in a Mo cleaning ?otation column at Highland Valley Copper mine indicated that increasing the proportion of small (< 1 mm) bubbles signi?cantly improved column metallurgical response, compared to typical operation. The results were a three- to four-fold Mo recovery increase and a 1 to 2% Mo (absolute) concentrate grade increase. The improvedcolumn operation produced a 4% Mo plant recovery increase. This study also showed that modelling the ?otation rate constant (k) as an inverse square function of Db was more accurate than considering k to be inversely proportional to Db.

Jan 1, 2010