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By K. W. Fritzsche

The prosperity of any nation depends, to a large extent, on its natural resources such as oil, coal, 'metal, timber, waterpower, and fertile soil. Each one of these resources forms the basis of a huge industry. The mining and smelting industry ranks among the first since it paves the way for a number of other industries. The mines and smelters provide a market for electric power, coal, timber, and agricultural products: other industries in turn provide a market for metals and non-metals. The real pioneering, however, is done by the prospector who goes into the wilderness to search for the ores from which the metals are to be extracted for the use of men. Prospecting is an interesting and fascinating occupation. There are many difficulties and hardships in the way but the lure of gold and the vision of finding an outcrop that may develop into a large bank account, within a reasonably short time, will urge the prospector forward. Thus, on the outskirts of this northern hemisphere hundreds of prospectors are searching and toiling and of whom nothing is known or heard until they reach civilization and announce a new discovery. Then a mad rush takes place and everybody who can afford to go will take a gamblers chance and plant stakes in the neighbourhood of the new discovery, or wherever an outcrop of mineralized rock can be found, with the hope of winning a fortune.

Jan 1, 1925

By Gavin Ritson, Chris Ward

"The oil sands industry is still fairly young with the first viable oil sand operation having been started in Alberta in 1960. Since then numerous modifications and improvements have been tried and implemented. The current process makes use of high velocity pumping of oil sands slurry with hot water (hydrotransport) to achieve separation of bitumen from the sand.A number of the oil sands processes have been adapted from unit operations that are used in mineral processing, such as crushing, screening, flotation, cycloning and thickening. This paper outlines a typical oil sands process flowsheet and investigates the differences and similarities in technologies and costs to other mineral processing industries. It also considers the very large throughputs required, and presents some of the difficulties and challenges currently faced by the industry as a result of high demand for oil and environmental pressures.INTRODUCTIONOil sands (also known as tar sands) deposits are found throughout the world. The Athabasca Oil Sands deposit in Aberta is the largest of these. Oil sands consist of a mixture of crude bitumen (a semi-solid form of crude oil), silica sand, clay minerals, and water. The Athabasca, Peace River and Cold Lake deposits cover 141,000 square kilometers and contain about 1.7 trillion barrels (270×109 m3) of bitumen in-place, comparable in magnitude to the world's total proven reserves of conventional oil"

Jan 1, 2009

By T. Richard Davies

This paper primarily deals with the application of wearfacing materials and their role within a well-established preventive maintenance welding program. Some examples are shown, as well as a synopsis of possible benefits and a compendium of methods and materials.

Jan 1, 1979

By Morris J. Viljoen, Young. David R.

"Abstract -The zone of economic interest at H.J . Joel Gold Mine is the VS5/Beatrix Composite Reef, a quartz-pebble conglomerate of Archean age. The reef occurs at the base of the Eldorado Formation, Central Rand Group, of the Witwatersrand Supergroup. At !east three stratigraphically distinct conglomerates form this economic zone. In order of deposition these are the Footwall, Beatrix, and the VS5/Beatrix reefs. The Footwall and Beatrix reefs are equated with the Aandenk Formation with transport directions toward the northwest, whereas the VS5/Beatrix Reef is of Eldorado age, with transport directions toward the south. The change in the drainage direction was caused by a major basin-wide tectonic event that occurred prior to the deposition of the Eldorado Formation. The Beatrix Reef was formed in a proximal, braided, fluvial environment by a process of aggrading gravel bars between channelways. The VS5/Beatrix Reef was formed by the desegregation of pre-existing Beatrix Reef with the introduction of new material containing much shale detritus and is seen to have been deposited in a more ·distal, braided, fluvial environment, similar to the Beatrix Reef.The average gold concentrations are different for each conglomerate; the Beatrix at 32.1 ppm Au, the Footwall at 24.4 ppm Au, and the VS5/Beatrix at only 12.4 ppm Au. A sedimentary gold concentrating process related to higher energy braid channels was primarily responsible for these high gold grades. Not only the basal unconformity surface, but also, internal degredation surfaces, were prime sites for concentration. An understanding of the spatial distribution of these differing conglomerates and their braid channels forming the economic reef zone is necessary in predicting ore grades for future mining."

Jan 1, 1994

By P. E. Davidson

The management of solid waste is known to be a large and increasing problem in high-population areas throughout the world. It is not necessary here to add further definition to the nature and magnitude of the problem. Instead, it is the purpose of this paper to describe a new process, called the Andco-Torrax System, which will be of use in converting municipal solid waste into useful energy forms and a granulated slag by-product. The paper includes a description of the first commercial plant for the process.

Jan 1, 1977

By M. M. C Jiménez, J. A. S Ténorio

For the recovery of valuable materials and for the protection of environment, recycling process of printed circuit board is an important subject of study. Moreover, the popularization of the computers and its technological evolution has generated a large number of waste electrical and electronic equipment. This paper presents a study of synergistic solvent extraction of copper, nickel and zinc from a sulfuric leaching liquor of printed circuit boards (PCB’s). The percent extraction of copper, nickel and zinc from dilute aqueous sulfate media besides synergistic effect of mixture of the .extractants Cyanex 272 and D2EHPA have been studied. Furthermore, different conditions such as temperature, pH of the feed solution have been examined. The results suggest that the synergistic effect of the .extractants mixture enhance the extraction efficiency of nickel.

Jan 1, 2014

By L. M. Pidgeon

"Part I. - PrinciplesIntroductionIf the oxides of the metals are listed in decreasing order of the magnitude of their heats of formation, the list appearing in Table 1 will be formed. It will be apparent at once that this is essentially the well-known electrochemical series (Table li). The metals at the bottom of the list exhibit great stability and are attacked only by the most violent of chemical reagents. Higher on the list, the metals become more reactive until, at the head of the list, the metals lithium and calcium are unstable in moist air.The reactive metals to be considered lie above manganese. In this group will be found familiar and abundant metals such as aluminium and magnesium, the unfamiliar yet abundant metal titanium, the rare and mysterious metal beryllium, and others of greater or less interest.While these metals exhibit properties as unlike as those of uranium and magnesium, they have in common a specialized and difficult extractive metallurgy. They form compounds of great stability, and their reduction is to varying degrees difficult. The position of a metal in Table 1 (and more particu1arly its position in the free energy column) gives a numerical value to this property.Oxides with low free energies of formation may be reduced with great ease; thus silver and mercury may be produced from their oxides by simple heating in air.Lead, iron, and zinc may be separated from their oxides by heating with carbon to moderate temperatures. Magnesium oxide, on the other hand, .requires a high temperature and very special conditions before it will yield magnesium metal."

Jan 1, 1950

"Batch flotation testwork demonstrated that a low-grade chromite ore from Bird River, Manitoba, was best floated at pH 2 using Armac C (coco amine acetate) collector and sulphuric acid as pH modifier. A grind of 100% minus 150 um was necessary for liberation, and flotation selectivity was greatly enhanced by prior desliming. A concentrate analyzing 24.2% Cr203 with a recovery of 90.2% was obtained, after three cleaning stages, from ore grading 6.05% Cr203. Total rougher collector concentration was 500 g/t and cleaner collector concentration 380 g/t. Similar grade and recovery were obtained during the pitot-plant evalualion, when a concentrate analy zing 22.3% Cr203 with a recovery of 93% (based on deslimed feed) was obtained for a total collector addition of 630 g/t.Selective flotation in a region of positive surf ace charge implies anionic activation, and a possible flotation mechanism is suggested.IntroductionIn an earlier study(1) of the beneficiation of chromite ore from Bird River, Manitoba, several methods of beneficiation were explored. These included ore sorting, heavy-media separation, and gravity concentration with flotation using Armac C (coco amine acetate) collector at pH 2, and sulphuric acid as pH modifier. Because flotation was not fully evaluated, a laboratory study was undertaken to determine the optimum parameters of chromite flotation. Optimization of parameters was established first on a laboratory scale followed by confirmation a t the pilot -plant level. Flotation of chromite using Armac C and sulphuric acid as a pH modifier has been reported as being selective for low-grade chromite ores(2)."

Jan 1, 1990

By Matthew D. Meyer

SMART, an association of surface mining companies formed in 1995 to develop a coordinated approach to technology development for the mining industry, has recognized the need for the establishment of a worldwide database that continuously collects mining equipment data and provides metrics related to productivity and cost. Under the auspices of SMART, Syncrude Canada, Suncor Energy and Albian Sands Energy (three oil sands mining operations located in northern Alberta) have established a pilot project for mine benchmarking. This presentation will include a review of the pilot progress including: ???Data gathering techniques: means of collection and storage, proposed practice for data control and normalization, access to data/reports and format for data. ???Reports/analyses for individuals, across groups, within the total industry pool and publicly. ???Security and confidentiality of information belonging to identified parties. ???Sharing of best practices among members. SMART has identified two key deliverables to ensure success of the project. First, data supplied from surface mines must be validated and normalized to common definitions and then analyzed to provide participating companies with regular reports that allow them to understand their position and resultant opportunities to achieve world-class performance. This model maintains granularity of the data for each operation that can then be recombined into standard comparisons or specific indices as required. The general categories of: operating delays, maintenance downtime, standby, and scheduled downtime, have been used to frame comparisons. Second, participating companies are looking to go behind the indices to identify and share best practices that distinguish particular operations. The spirit of cooperation between the companies involved in the pilot project is meant to be a model for future expansion of the benchmarking project.

Apr 1, 2005

By Bill Dupley

We believe that the inability of employees to effectively manage information has reached an epidemic problem throughout the corporate world. ? All the available knowledge in the world is accelerating at a phenomenal rate. ? The whole world's codified knowledge base (all historical information in library books and electronic files) doubled every 30 years in the early 20th century. ? By the 1970s, the world's knowledge base doubled every seven years. ? Information researchers predict that by the year 2010, all the world's codified knowledge will double every 11 hours.

May 1, 2003

By A. R. Khodabandeh, T. Nematkhah

Correct selection of forging parameters is very important to produce sound superalloy parts. In this investigation nickel-iron base superalloy IN901 successfully forged and seal spacer, which is a part of airplane with about 11 kg weight has been produced. Forging has been performed on the basis of hot compression results, which show deformation above 1100°C associated with dynamic recrystallization (DRX) which can increase the workability of material. On the other hand annealing at 1100°C decreases the flow stress during hot compression, and then increases the material formability. Then billets annealed at 1100°C in electrical furnace for 24 hours and reheated again to 1100°C before forging. Initial square cross section billet with 128mm side and 202mm length forged immediately after reheating by 80MN mechanical press. Specimens forged in five steps: upsetting, three steps molding and finishing. Preformed and molded specimens reheated in electrical furnace before later step of forming. Finally specimens trimmed by 1 OMn mechanical press and hot set by hydraulic press and then cooled in air to room temperature. Results show that reheating temperatures has been selected correctly because there isn't any surface crack and die cavities filled completely by forging material. Material flow has been carried out properly and there isn't any defect in critical points especially in extradoses and intradoses. Microstructural examinations show that grain boundaries contain Ti-rich globular particles that formed during cooling.

Jan 1, 2006

By Terry Bachynski

_ Regulatory Process _ Approval Timelines _ Trends _ Stakeholder Consultation Expectation _ Challenges _ Initiatives for Regulatory Process Reform _ A Better Way? Alberta Regulatory Process _ Regulatory Approval of a major capital development requires multiple approvals from several regulatory authorities: ? EUB ? Decision Report approves development scheme and recommends conditions for other regulatory agencies ? AEnv ? approvals to construct, operate and reclaim required prior to any in field construction activity ? Federal - approvals for federally regulated activities ? Municipal ? Development Permit

May 1, 2004

By J. H. Rickard, D. H. Watkinson

"Abstract - Detailed petrographic and quantitative (electron microprobe, SEM-EDS) mineralchemical analyses of sulfide ore from the 100 orebody at the Copper Cliff North mine, Copper Cliff, Ontario, reveal numerous stages of ore development. Sharp contacts between weakly mineralized quartz diorite and blebby to massive sulfides indicate multiple intrusive events within the Copper Cliff offset dike. A spatial association of sulfides and hydrous minerals, such as amphibole, biotite, chlorite and epidote, suggests that most primary ore has been affected by later hydrothermal fluids. Sulfides are often enclosed or bordered by these secondary silicate phases. The ore consists primarily of pyrrhotite, pentlandite, chalcopyrite, with trace michenerite, cobaltite/gersdorffite, irarsite, hessite, tsumoite, and bismuth tellurides.Geological and petrological comparison of the 100 orebody and the adjacent 900 and 890 orebodies has revealed distinct similarities in ore distribution. Data show that the 100 orebody is depleted in platinum-group elements (PGE) relative to the 900 orebody. Platinum-group elements from the 100 orebody may have been hydrothermally remobilized and partly emplaced in the 900 orebody, in adjacent veins, or in magmatic breccia. Analysis of Cu, Ni, and PGE assay data of ore samples has characterized their distribution among the eight different ore textures in the orebody. There is a strong association between Pt and interstitial sulfide, and to a lesser extent massive sulfide, but little correlation between chalcopyrite-rich ore and PGE in the 100 orebody, unlike many other deposits in the Sudbury region."

Jan 1, 2001

By Gerald R. Larocque, Donald F. Grenville

"IN APRIL, 1965, the employee relations department (then called the personnel department) was established as a separate function within the company. Its aims and objectives were to hire an effective work force to operate the open-pit mine and the mill, which were at that time under development and construction. It was also directed to develop a sound policy for employee relations to assist the company in maintaining a stable and properly motivated work force, which included the establishment of satisfactory wage rates and fringe benefits, safety, fire protection and security. During the 8 years that the department has been in existence the scope of the company's operations has expanded to include a zinc plant and an underground mine. The work force has enlarged accordingly and now totals 1,680 employees working at the two sites, separated by 34 road miles. To cover the employee relations functions the department has a total of 29 members at the two sites. The department is organized under a superintendent, who has an employee relations supervisor, a safety director and a fire chief reporting directly to him. The employee relations supervisor, with 2 employment officers and 2 clerks, handles hiring, first-stage employee grievanoos, terminations, employee records, and the organization of company-sponsored functions and meetings. Safety, training and security are the responsibility of the safety director, who has 3 safety supervisors, 16 security men, 1 first-aid attendant and one hearing conservation technician to service the two sites. The fire chief operates as a one-man section responsible for plant-wide fire inspections and fireoriented training. Although"

Jan 1, 1974

By J. W. Coetzee, H. E. Deist

Carbon-in-pulp (CIP) and Carbon-in-leach (CIL) processes are used extensively in the gold mining sector to recover aurocyanide from solution. This paper discusses the modelling of these operations, using various simplifying assumptions, in order to simulate the effect of changing operating conditions on the dynamics of the system. It is assumed that the adsorption and leaching rates are a function of concentration difference between the source phase and recipient phase. The simulation was set up using Matlab's Simulink interface. Plant variables are solved using a medium scale Newtonian search algorithm in Matlab, where the differences between the actual and predicted plant outputs are minimized on a continuous time-line.

Jan 1, 2005

By T. Belem

The main objective of this study is to better understand the effect of underground CPB placement conditions on its microstructural, hydro-mechanical and geochemical properties. To reach this objective, three PVC columns, each 3 m high, were built, and were filled with CPB material. The columns allow simulating undrained (UD), half-drained (HD) and fully-drained (FD) conditions along with the measurement of resulting self-weight consolidation settlement of the CPB. Bleed and drainage waters were also collected from each column for geochemical analyses (pH, Eh, EC, SO42- content). After 90-days of curing time, a total of sixty CPB samples were cored from the backfill columns and subjected to uniaxial compression tests followed by physical characterization (Gs, void ratio, water content, degree of saturation, specific surface area). The results showed that the total drainage water and the maximum observed settlement occur mainly within the first 72 hours after the columns are filled. The corresponding volumetric strains suggest that in situ backfilled stopes simulated behave in a similar way to the fully-drained (FD) or the half-drained (HD) conditions. The MIP test results show that the pore structure varies between the top and the bottom of each column.

May 1, 2007

By J. Esson, R. A. D. Pattrick, M. K. Nimfopoulos, D. A. Polya, K. M. Michailidis

"Abstract-Economic Mn-oxide ore deposits of commercial grade occur in the Rhodope massif near Kato Nevrokopi in the Drama region, Northern Greece. The Mn-oxide mineralization has developed by weathering of continental hypogene rhodochrosite-sulphide veins. The vein mineralization is confined by tectonic shear zones between marble and metapelites, extending laterally into the marble as tabular, pod or lenticular oreshoots (up to 50 m ?? 20 m ?? 5-10 m). Supergene oxidation of the hypogene mineralization led to the formation of in-situ residual Mn-oxide ore deposits, and secondary infills of Mn-oxide ore in embryonic and well developed karst cavities.Whole rock geochemical profiles across mineralized zones confirm the role of thrusts and faults as solution passageways and stress the importance of these structures in the development of hydrothermal and supergene mineralization at Kato Nevrokopi. Three zones are recognized in the insitu supergene veins: (A) a stable zone of oxidation, where immobile elements form (or substitute in) stable oxide mineral phases, and mobile elements are leached; (B) a transitional (active) zone in which element behavior is strongly influenced by seasonal fluctuations of the groundwater table and variations in pH-Eh conditions; and (C) a zone of permanent flooding, where variations in pH-Eh conditions are minimal. Zone (B) is considered as the source zone for the karst cavity mineralization. During weathering, meteoric waters, which were CO2-rich (PCO2 ~10-3.8 to 10-1.4) and oxygenated (fO2 ~10-17 for malachite), percolated downward within the veins, causing breakdown and dissolution of sulfides and marble, and oxidation of rhodochrosite to Mn-oxides. Karst cavity formation was favored by the high permeability along thrust zones. Dissolved Mn2+ was transported into karst cavities in reduced meteoric waters at the beginning of weathering (pH~4-5), and as Mn(HCO3)2 in slightly alkaline groundwaters during advanced weathering (pH~6-8). Mn4+-oxide precipitation took place by fO2 increase in ground waters, or pH increase by continuous hydrolysis and carbonate dissolution. In the well developed karst setting, some mobility of elements occurred during and after karst ore formation in the order Na>K>Mg>Sr>Mn>As>Zn>Ba>Al>Fe>Cu>Cd>Pb."

Jan 1, 1997

By J. L. Huisman

Bio(hydro)metallurgy is the latest development in the ongoing search for efficient and economic metal winning processes. In addition to bioleaching, other biotechnology-based applications are becoming more and more accepted. In this paper the THIOMET process for general effluent treatment is described. With this process, it is possible to produce sulfide on-site and on-demand and to use the sulfide to precipitate metals, even selectively when required. The process is ideally suited as a treatment to remove metals after, for example, an acid regeneration process. Another process is proposed that deals with stainless steel pickling bleeds. Such effluents typically contain nitrate, iron, nickel, chromium(VI) and other species. This one process handles these compounds, as well as other metals.

Jan 1, 2006

By M. Doucet

The introduction of high-nickel anodes to CCR in 2006 resulted in an increase of nickel in anodic slimes. Removal of the nickel in these slimes to below 3.0% is necessary in order to prevent slag viscosity problems in the subsequent pyrometallurgical step. A lower specification of 0.5% was chosen in order to minimize Ni losses to the slag and to recover this nickel as NiSO4. A 2-stage autoclave process, which was patented by CCR in 1992, was chosen to treat the high nickel slimes. Laboratory and plant?scale tests were performed in 2004 in order to validate the results of this process with the present slimes. These results along with corrosion tests were used to design two brick-lined autoclaves. These autoclaves were installed in October 2006 and successfully commissioned within 8 weeks. A "Design of Experiment" test program was performed in 2006 on an alternative autoclave process that reversed the cycles in the patented process. The effects of temperature and acid content were modeled using the results. The alternative process will be validated with the new autoclaves.

Jan 1, 2007

By C. Dirscherl, M. Combes

"Declining ore grade, leading to increased material transport and plant throughput requirements, is one of the major challenges in the current mining environment. This is accompanied by rising energy and labor costs, decreasing plant productivity and the requirement for highest plant availability. Siemens’ answer is the latest gearless drive technology for grinding and conveying. Gearless drive solutions are surpassing the mechanical limits of conventional drive systems serving to utilize the principle of economies of scale. By elimination of various components of the drive train the maintenance activities and spare parts inventories are reduced. The advantages are culminating in the incomparable availability of the Siemens’ gearless drive technology of 99.46 to 99.71% - as confirmed by real operational data from the Antapaccay mine in Peru. It was the first plant worldwide to use gearless drives for both applications.INTRODUCTION – THE GEARLESS PRINCIPLE The principle idea behind a gearless drive system is to reduce the number of components and diversity of parts. Especially those components that are at the edge of current manufacturing or power limits are eliminated. The used equipment provides the possibility to scale up and increase the power transmitted to the driven machine. This finally results in a possible increase of throughput respectively transported or processed material. In order to apply this principle of simplification we will take a look at the components of a conventional drive system consisting of: - Driven equipment (mill, conveyor, slurry pump) - Components altering the rated speed (gearboxes, girth gear / pinion) - The electric motor - Starting devices for the motor (VSD, CCV, LRS, clutch), which are necessary because a direct across-the-line start of high power motors with load would result in a significant drop in the line supply voltage - Alternatively a variable speed drive (VSD) or cycloconverter (CCV) to utilize the possibility of speed variation during operation - The electrical supply system (cables, switchgear, transformers, protection equipment)"

Jan 1, 2014