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By H. E. T. Haultain

I HAVE considerable hesitation in preparing and presenting this paper. These machines have been such an intimate part of my own experiences and predilections for such a long time that J would find it difficult to tell the story in an impersonal way. They have had several attractions for me. They were needed for the study of the fundamental features of modern milling, size analysis and accurate batch concentration of the very fine particles. I had been a millman once, a real operating millman, and, when I became academic". I always had the craving to link the academic laboratory with the field, as Rittinger and Richards had done. My first milling experience was with a small concentrator at a tin mine in Bohemia, forty-seven years ago. There was no assay office and the testing of our tailings was by means of a "Vanning Shovel", introduced from Cornwall by Captain Josiah Thomas, the great Josiah of Dolcoath, some fifteen years previously. This was a most effective instrument and it has always been a puzzle to me that it has not been more universally used by millmen. Later, at Freiberg, on the other side of the Erz Gebirge from the tin mine, I was introduced to the "Sichertrog", made out of wood shaped something like a very shallow boat or an elongated saucer, a most effective piece of apparatus when. the difficult technique of handling it was once achieved. Later, in the Slocan in British Columbia, my partner, the late Maurice Bucke, used a short length of flat trough or launder suspended by four wires, with which he got very satisfactory results as a small batch concentrator. In the University laboratory we had frequent need for something of this kind, and many efforts were made to solve the problem. With W. E. Johnston, we were working on the problem of gold-bearing telluride ores, which called insistently for a separation of the very fine telluride particles which existed only in minute quantities in the Kirkland Lake ores. Under this spur there finally developed the Superpanner, which is a mechanized combination of the Vanning Shovel, the Sichertrog, and the Maurice Bucke suspended launder.

Jan 1, 1937

By M. Härting, D. T. Britton, M. Nzikou Mamboukou

"Copper containing different types of nanocomposites have been characterized for nanolabelling and ID. Three types of the rare earth nanoparticles were used for this study, the oxide and the sulphur compound of the Eu and Tb. Characterization techniques uses SEM, and Raman for morphology, chemical composition, and optical characterization respectively. It has been shown that it is possible to include the rare earth particle in a copper matrix without damaging its physical properties. INTRODUCTIONThe development of new materials, often involves the addition of new properties without changing the beneficial properties of the original material (Chen et al., 2009; Khana et al., 2007; Patil et al., 2008). Nanocomposites are nanostructured materials, whose structural elements including clusters, crystallites or molecules, of dimensions ranging between 1 to 100 nm (Moriarty, 2001), or a composite material where one of the phases is a one, two or three dimensionally nanostructured material (Nanotechnology, 2006; Wang, 2001). Nanocomposite materials research is a fast growing area due to the high demand for materials for specialized applications (Edelstein & Cammarata, 1998), such as biolabelling, magnetic storage media, solar energy transformation (Jisen et al., 2004), and resistance welding applications (Bessergenev et al., 1997; Kwon et al.,2006).The properties of the nanocomposite materials depend not only on the properties of their individual parent materials, but also on their morphology and the interfacial characteristics. Thus, significant efforts have been focused on the control of the nanoscale structures via innovative synthesis approaches. Therefore, novel materials of unique properties may be obtained by combining properties from the parent constituents into a single material (Balan, 2006; Garcia et al., 2009). Possible effects of nanocomposites in the original material may include changes in the mechanical properties such as hardness , wear resistance (Rafaja et al., 1987), and electrical properties (Britton et al., 2003). The inclusion process may therefore be used to tailor materials to have particular mechanical, electrical and optical properties (Das et al., 2009). However, to fully understand the nanocomposite, it is necessary to study the fundamental properties of both the host matrix and the inclusions (Li, 2008)."

Jan 1, 2012

By E. Latorre, T. S. Golosinski

ABSTRACT; his paper proposes new methodology to define the pit limits that yield the maximum net present value (NPV) for a deposit, under a given economic scenario and for a given discount rate. The method uses an algorithm that combines dynamic programming and heuristics. It was tested for evaluating deposits with different sizes and various grade distributions. For the discount rate of zero, the results confirm that the economic pit limits are the same as that defined using Lerchs Grossman method. However, when discount rates higher than zero are used, the pit limits differ, yielding a higher NPV.

Jan 1, 2011

By J. Lui

Inco Copper Cliff Smelter commissioned two new Inco flash furnaces in 1991/1993 as part of its S02 abatement program. Each flash furnace is equipped with a fluid bed dryer. The ~ 12 wt% water content in the concentrate filter cake, flux, reverts and sludge is removed in the fluid bed dryer. The dry solids are discharged from the dryer together with exhaust gases into the baghouses where they are separated. The dry solids are transferred to four storage bins. In September 2003, for the first time since startup in 1991/1993, a large amount of elemental sulfur accumulation was discovered on the walls, roofs and floors of the outlet side of the baghouse chambers. Several baghouse fires were experienced during cleaning and conducting maintenance work in the elemental sulfur contaminated baghouses. Laboratory scale test work at the Inco research lab was conducted to understand the mechanism. A plant solution to minimize elemental sulfur formation was implemented with success. This paper summarizes the efforts to understand and minimize elemental sulfur formation in the baghouse chambers.

Jan 1, 2007

By M. Tadayonsaidi

The effect of alloying elements on the mechanical properties and thermal expansion of 336 casting alloy usually used as piston alloy which has low thermal expansion and very good high-temperature mechanical properties and good wear resistance was investigated. The mechanical properties and thermal expansion characteristic of samples with different combination of alloying elements, which enhance to reduce the cost of products, have been studies, The results show remarkable increase in the mechanical properties with increasing the amount of Cu and Mg, while are reduced with increasing amount of Ni, On the other hand, the use of eutectic aluminum alloy as 336 alloy with higher percent of Cu and Mg and lower percent of Ni are recommended for industry, due to economical viewpoint and satisfactory properties.

Jan 1, 2005

By P. J. Routledge

THE purpose of this paper is to discuss the practical aspects of locating gravel deposits and of establishing efficient, portable concrete aggregate beneficiation plants for use on construction projects where limited amounts of high-quality gravel and sand are required. Certain projects are listed, in order to demonstrate the wide variety of problems encountered. Routledge Gravel Contractors Limited, North Vancouver, have supplied concrete aggregate for construction projects in British Colum-bia since 1957. In tl1at year, in sup-plying aggregate for a small project at a site on the northern coast of British Columbia, our quote was as follows: Concrete aggregate to specifications, f.o.b. scow, North Vancouver$ 1.75 per cu. yd. Scowing charges to site. $16.00 per cu. yd. At that time, our company realized that more attractive quotations could be submitted if local gravel was utilized where available. Port-able equipment was then acquired and a simple screening plant (Figures 1 and 1a) was at first used. This was later replaced by heavier, more versatile equipment. The use of suitable equipment, the keeping of cartage to a mini-

Jan 1, 1962

By Luke Evans

What are Best Practices? What are Bad Practices? Who Uses Best Practices? Why Bother? Acceptability Guidelines Published Best Practices Published Bad Practices Additional Best Practices Some Best Practices for Low Grade Deposits Interpretation Guidelines Big Bear Gold Deposit Example Conclusions Questions

May 1, 2013

By H. Golzarpoor

Life Cycle Analysis (LCA) is a methodology for evaluating the environmental impacts associated with a product during its life cycle. LCA is identified as the most reliable method for verifying environmental impacts; however, current LCA-based approaches have certain limitations for environmental analysis of construction products. Integration of the LCA methodology with Discrete Event Simulation (DES) provides a sound framework for modeling and analysing the environmental impacts of construction products. LCA and DES is one possible combination for analysing the cause and effect of various scenarios where time, resources, and randomness of input variables affect the outcome and, therefore, has the potential to address the shortcomings of LCA in construction. Recent studies in disciplines other than construction such as manufacturing systems have revealed positive effects on evaluation of environmental metrics while integrating LCA with DES; however, this integration has not yet been applied for environmental analysis of construction products. By implementing LCA data in a DES model, this research proposes an environmental model of earthmoving operations in a case study. Environmental variables are simultaneously assessed with production variables in the same simulation model and the integration of DES and LCA is discussed.

Aug 1, 2013

By J. A. Finch

The metallurgical performance of a flotation cell is strongly influenced by the features of the bubble population, characterized by the gas dispersion properties, a collective term including bubble size, superficial gas velocity and gas holdup. It is required that gas be well distributed throughout the cell. Gas distribution is estimated here by simultaneous measurement of gas velocity (Jg) at different distances from the center (radial Jg mapping). This communication describes a technique to perform radial Jg mapping together with fundamentals for the interpretation of the data.

Jan 1, 2009

By Donald J. MacNeil

THE opinion, based upon geological knowledge, that certain areas within the Province of Nova Scotia might yield commercial quantities of petroleum, is not new. It dates back to at least 1864, when the Pioneer Oil and Salt Company drilled some shallow holes in search of oil near lake Ainslie, Cape Breton. As a matter of fact, several companies were engaged in oil exploratory work near lake Ainslie at about that time; included among them were the Inverness Oil and Mining Company, the Victoria Oil Company, the American Oil Company, and the Cape Breton Oil and Mining Company. Oil exploration by these and other companies was conducted sporadically on Cape Breton island until 1914. In several instances, the depth of the test holes exceeded 1,000 feet; the deepest was carried to 3,260 feet. The Lake Ainslie area was selected because oil seepages were present along certain sections of the lake shore, but the tests that were drilled to tap the oil-bearing zone failed to yield anything of commercial value. Currently, there are three areas in Nova Scotia wherein active exploratory work is being conducted, namely, at Pugsley Siding close to Amherst; at Kennetcook, Hants county; and near Mabou, Inverness county. The Pugsley Siding test is being drilled by the Sun Oil Company, of Philadelphia; the work at Kennetcook is under the direction of the Nova Scotia Oil and Gas Company; two relatively deep holes were drilled by the Lion Oil Refining Company in 1944 near Mabou, and, as a result of the additional geological information derived therefrom, another test probably will be drilled by this Company in the same area. Aside from these activities in the search for petroleum, the oil possibilities of several other sections of the Province are being studied by means of surface geological mapping.

Jan 1, 1945

By Peter Hayes, Evgueni Jak, Taufiq Hidayat, David Grimsey, Denis Shishin

"An integrated nickel flash smelter is operated with Peirce-Smith converters at the Kalgoorlie Nickel Smelter. To improve the partitioning of arsenic between slag waste and matte product, an option to modify the slag–matte chemistry by addition of CaO was analysed. A combination of plant sample analysis, high-temperature laboratory experiments and thermodynamic modeling was carried out to evaluate the process options. The high-temperature experiments involved the re-equilibration of industrial matte-slag samples at 1225 °C and P(SO2) = 0.12 atm, rapid quenching in water, and direct measurement of phase compositions using electron probe X-ray microanalysis (EPMA) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LAICPMS). A private thermodynamic database for nickel sulfide smelting and converting was used together with the FactSage thermochemical software package to assist in the analysis of the distribution of elements between slag and matte as a function of CaO addition. The thermodynamic predictions combined with experimental data obtained in this study can be used to characterise the effect of CaO fluxing on the slag–matte thermochemistry during the nickel sulfide converting.INTRODUCTION At the Kalgoorlie Nickel Smelter (KNS), nickel sulfide concentrate is processed in an Outotec-type flash furnace to produce nickel matte containing +47 wt% Ni. Separation of nickel matte and waste slag from the flash smelting is enhanced through settling in the electric arc -heated zone attached to the flash furnace. The flash furnace matte is further processed in a Peirce-Smith converter to produce Ni-rich matte containing +66 wt% Ni (Crundwell, Moats, Ramachandran, Robinson, & Davenport, 2011). Iron silicate-based slag is used in the converting process at KNS. Most of the arsenic is contained in the final matte and very little of the arsenic partitions into the slag. Previous work by Font et al (Font, Hino, & Itagaki, 2003) shows that the distribution ratio of arsenic between calcium ferrite slag and nickel-matte (LAsslag/matte) is significantly higher than that between iron silicate slag and nickel-matte, where LAsslag/matte = (wt pct As in slag)/{wt pct As in matte} (1)"

Jan 1, 2017

By Ivan Malinsky, Gérard Castonguay

"On a développé un procédé qui donne une fonte (2,3% C, 0,07% V) du V2O5 (99%) et un rutile synthétique (94% TiO2) à partir d'un minerai, dont les réserves au Québec sont importantes. Le procédé comprend les opérations suivantes: 1) la concentration magnétique du minerai (30% Fe, 9% TiO2 et 0,65% V2O5) pour produire un concentré (65% Fe, 7% TiO2 et 1,6% V2O5); 2) le smeltage du concentré aggloméré dans un four à arc, sans fondant, pour produire une fonte et une scorie (30% FeO, 40% TiO2 et 8,0% V2O5) qui contient plus de 95% du vanadium et du titane présents dans le concentré; 3) le grillage alcalin (37% Na2CO3) de la scorie suivi d'une lixiviation à l'eau et de la précipitation de l'hexavanadate d'ammonium à partir du filtrat; 4) la lixiviation du résidu par l'acide sulfurique pur ou usagé pour produire un rutile synthétique. Un estimé préliminaire de la valeur économique du projet laisse croire à sa rentabilité à la condition que l'investissement pour le smeltage soit inférieur à environ 400$/tonne de fer.IntroductionLes gisements de magnétites titanifères sont nombreux dans le monde. Ils consistent en une magnétite étroitement liée a l'ilménite, La teneur trop élevée en TiO2 empêche l'exploitation de ces gisements pour la production de fer. Cependant, dans certains cas, la magnétite a une teneur intéressante en vanadium qui peut rendre l'exploitation de ces gisements rentable. Aujourd'hui, les magnétites titanifères constituent la plus importante source de production de vanadium. On estime qu'environ 70% du vanadium produit provient de ces sources."

Jan 1, 1983

By J. W. Merkley, K. B. Hustwick

"The authors describe the use of a computer system for the control oj warehouse inventory at Cominco's Canadian operations. The challenge presented by the company's diverse products and various locations necessitated a practical approach to operational and manpower requirements. The utilization of modern forecasting techniques, manual intervention and exception reporting provides system flexibility. The system also provides both operational and management control to set required service goals at the lowest inventory levels for inventory management.IntroductionCominco Ltd. is a Canadian company, with international operations, the principal business of which is zinc, lead and chemical fertilizer s. Its involvement is fully integrated and range s from mineral exploration through mining, smelting, refining and by-product production to international marketing. It also embraces related services, including trade, wharfarge and power. With head office in Vancouver, it is involved, directly or through subsidiary or associated companies, in Canada and in the United States, Greenland, Europe, Australia, India and Japan.Cominco has over 12,000 employees and 26,000 shareholders, with 91% of all shares held in Canada.Cominco's Inventory Control System is one of the most extensively used computer systems employed by the company. Also, inventory control is regarded as one of the most economically successful computer applications to be undertaken by the Data Processing Services (D.P.S) Group that was responsible for the development of the Inventory Control System.The main use of automatic inventory control has been at operating plants in Western Canada and the Northwest Territories, which are separated by large distances. Each location has equipment-intensive mining and processing operations and it is essential to maintain control of parts and supplies inventories. Some of these locations are remote from urban and industrial centres and it is important to avoid the adverse effects of high personnel costs and re-training due to turnover."

Jan 1, 1982

By Muhammad Zaka Emad

Cemented rockfill (CRF) is a mixture of rock aggregate and binder slurry. It is a stiff backfill, it is fast curing, its operation is simple, placement rate is reasonably high and no drainage is required. The main demerit of CRF is failure of exposed faces causing ore dilution, which can be associated with the fill placement method. This paper discusses the effects of two placement methods being practiced by mines and numerical modelling is used as a tool to evaluate stability of the backfill column. In the first method, practiced in longitudinal retreat mining of a narrow vein deposit, the rockfill is hauled and dumped into the stope with a LHD scooptram. Once dumped, cement slurry is sprayed into the stope. In the second method, a raise situated centrally above the mined stope is used to convey already mixed CRF into the stope. Stopes are mined out transversely in primary and secondary blocks in a sublevel stoping system. Problems of poor mixing in combination with both placement methods are discussed. The two backfill placement methods are analyzed for blast induced vibration damage using the dynamic Flac3D modelling technique accounting for rock mass and fill damping characteristics, and a pressure wave is used to simulate the blast vibrations. Fill heterogeneity has also been considered for the two cases and results are compared.

Jun 1, 2012

By John Kostuik

AT the Sladen-Malartic mine, a number of orebodies have been mined, some by shrinkage and others by open sub-level scopes, from which the ore is handled either through a grizzly system or by mechanical loaders. This paper deals with the comparative costs and relative merits of the two handling arrangements. The facts brought out in this comparison have a bearing on the selection of a proper handling method. The mine is in Fourniere township, northwestern Quebec, about forty miles east of the town of Rouyn. It is served by the Rouyn-Senneterre branch of the Canadian National railways. Two vertical three-compartment shafts give access to the present workings. No. 1 shaft, at which the plant is centralized, is the main hoisting shaft, with five levels to 950 feet. No. 2 shaft, 2,400 feet east of No. 1, is under development, with four levels to 725 feet. At the main shaft, the ore is hand-trammed in 1 1/2 tons cars from the scopes to the stations o:i each level and hoisted in cages to surface at a rope speed of 900 feet per minute. Air-operated tipples are used to dump the ore through grizzlies of 14-inch openings into a surface bin of 150 tons capacity. The ore hoisted at No. 2 shaft is trucked from the headframe bin to the mill. Milling commenced in January, 1938, ar a daily rate of 250 tons. Within two months this rate was increased to the unit's maximum capacity of 325 tons. A second unit to treat a further 325 tons daily was installed in April, 1939. The orebodies mined at No. 1 shaft are parts of a silicified zone at the contact between syenite porphyry and greywacke. The zone is ten co sixty feet wide, strikes easterly, and dips to the south at 55 to 85 degrees. The hanging-wall of the zone is marked, though not precisely, by a strong gouge fault. Locally, the boundary of silicification may be as much as twenty feet either above or below the fault, but for practical mining purposes the fault is the hanging-wall of the ore-zone. The footwall roughly parallels the fault, but as an assay wall it is usually irregular in detail. The ore is dense and hard, a siliceous replacement of both porphyry and greywacke, mineralized with fine disseminated pyrite.

Jan 1, 1941

By J. M. Hollicky

The economical processing of wet and sour natural gas presents a problem due to the seasonal demand for natural gas. The plants must be sized to handle the peak loads but may only operate at half capacity on the average, in which case the sales value of sulphur and hydro-carbon liquid by-products cannot support the operating and capital costs of the plant. This must result in an increased price for the gas. This problem was solved by Pacific Petroleums and Westcoast Transmission in the design of their pipeline and plant facilities now operating in the Peace River area, where there are both wet and dry gas fields. By .building a plant to process sufficient wet gas to pro-vide the base load requirement, and by drawing on the dry gas fields for peak loads, an optimum economic operation was ?possible. The sulphur, L.P.G., and gasoline produced not only are able to support the operating and capital costs of the pro-cessing plant, but were instrumental in the sharp drop in retail prices of these commodities in the area. The sour gas and condensate is gathered from the fields in the area and transmitted in a two-phase gathering system to the gas processing plant at Taylor, B.C. The condenrnte is knocked out in inlet scrubbers. Hydrogen sulphide and carbon dioxide are removed in an amine scrubbing unit. The hydrogen sulphide is stripped from the amine and is sent to the Jefferson Lake Sulphur Company's plant which produces sulphur by the partial oxidation of the hydrogen sulphide. The natural gas, now sweet, is processed in an absorption unit to recover additional liquids, before being de-hydrated to remove water. It is then sent to Westcoast's main c8mpression station. The condensate recovered in the inlet scrubbers and the liquid re-covered in the absorption unit are fractionated to remove fuel gas, used in the plant, and to produce pro-pane, butane, and naphtha. The pro-pane and butane are scrubbed with caustic soda to remove hydrogen sulphide. The naphtha is treated with hydrogen in a unifiner unit to re-move sulphur compounds completely, and is split into a light and heavy naphtha. The heavy naphtha is .catalytically reformed to produce a high-octane blending-component. These fractions are blended with components produced from crude oil at the Dawson Creek refinery to produce a high-quality balanced gasoline with special attention being paid to volatility for ease of starting, warm up, and engine cleanliness, and octane for power and ?performance.

Jan 1, 1958

By Descarreaux. Jean

"The Abitibi volcanic belt was sampled along a cross section extending from Matagami to a point east of Rouyn. A few samples were also collected in Louvicourt township, Quebec. The major elements were determined for 344 samples, and rock names were defined using normative minerals. The analytical data were studied by means of variation diagrams. The Abitibi volcanic belt is characterized by rocks belonging to both the tholeiitic and calc-alkaline magmatic series, but they show some differences as compared to some typical reference series, particularly those from Japan. Basalt is the predominant rock type and accounts for 44 per cent of the sampled outcrops. The volcanic rocks are relatively poor in K2O and TiO2. Regionally, the volcanogenic copper-zinc mineralization is associated with the calc-alkaline volcanic sequences. Locally, within such sequences, some types of abnormal deviations from the averages are recognized only in association with the copper-zinc mineralization. The anomalies are ascribed to hydrothermal alteration consisting of the introduction of MgO and removal of N a20; enrichment in K20 is also observed where zinc mineralization predominates. Examples of such anomalous zones show that, in places, this alteration phenomenon can be quite extensive. Petrochemical characteristics can be used as geochemical ore guides in exploration programs."

Jan 1, 1973

By W. J. Dick

THE purpose of this paper is to point out, briefly, the importance of the coal mining industry of Alberta and to stress the economic factors that hinder its development; also to offer suggestions relating to the major problems of the industry. The minor problems will not be dealt with in detail, because, if the major problems are taken care of, it is felt that the industry itself can take care of ,he remainder. COAL MINING NO LESS IMPORTANT THAN GOLO MINING The large increase in metal mining development in all provinces of Canada, excepting Saskatchewan, Alberta, and the Maritimes, has had the effect of focussing public attention on this branch of the industry. The fact, also, that this development came at a time of depression has been of immense benefit to Canada as a whole. On account of the necessity and consequent demand for gold, with its attendant increase in price, through government action, from $20.67 per ounce to $35.00 per ounce, it is safe to say that the public of Canada have become, today, gold mining conscious. While everyone admits the great value. of the gold mrn111g industry, nevertheless, the equal value to Canada of certain other industries must not be lost sight of. The coal mining industry, in particular, is worthy of greater public and government support than has been accorded it in the past. It would seem unnecessary to stress this matter to a meeting of the Canadian Institute of Mining and Metallurgy, but unless certain facts are brought to your attention, there is danger that the coal mining industry will not be developed to the extent its national importance deserves. Too many public men and men in authority are unaware of the value of coal mining.

Jan 1, 1936

By S. Nakamura, M. Takaoka, Y. Mizuno, T. Kusakabe

"Mercury is produced as a byproduct from gold mines and, historically, has been transferred to recyclers and used for various industrial processes and products. However, under the Minamata Convention on Mercury, adopted in 2013,the intentional use of mercury in processes or products will be minimized in the world. Surplus elemental mercury should be treated as a hazardous waste and consequently, should be converted to a more stable chemical form for long-term storage or permanent disposal. A stabilization method has been developed to react mercury and sulfur using a planetary ball mill. The planetary ball mill can produce high-energy conditions and enable samples to react within a short period of time. A series of tests has been conducted to confirm that mercury sulfide can be produced using a bench scale machine with 2400 mL pot. Under a suitable experimental condition with 25 mm ball diameter, 30%of ball filling rate and 1.05 of molar ratio of S/Hg, a powdered mercury sulfide product was successfully obtained in 60 minutes. The leach ability and atmospheric emission from the product was extremely low. This stabilization method would contribute to an environmentally sound mercury management strategy for the gold industry.INTRODUCTIONDue to its unique physical and chemical properties, mercury has numerous applications, including in industry and medicine. However, mercury and its compounds are highly toxic. For example, in Japan, methyl mercury in waste water caused Minamata disease in the 1950s, which affected large numbers of people (Minamata Disease Municipal Museum, 2001). In recent years, environmental pollution caused by emissions and releases of mercury into the atmosphere, waterbody and land by various emission sources such as coal fire plants, artisanal and small-scale gold mining (ASGM), non-ferrous metal industries, waste incinerations etc. has also become a significant problem. To protect human health and the environment from anthropogenic emissions and releases of mercury and its compounds, the Minamata Convention on Mercury was adopted in 2013(UNEP, 2013)Because ground gold ore typically contains mercury at 0 to 100 ppm, mercury is often produced as a byproduct from gold mines (UNEP, 2016). In gold mining operations, mercury can be released from the ore by roasting or by leaching in cyanide solutions and recovery onto activated carbon. According to Yanget al. (2016), 85.1%of mercury in a concentrate was vaporized during a roasting process. Both processes finally discharge elemental mercury as a byproduct. In the USA, more than 100 ton of mercury was discharged from large-scale and industrial gold mining (Miller, 2004)."

Jan 1, 2017

By C. I. Walker

Field tests at a number of large mineral processing operations have been undertaken to better understand the wear life impact of different aspects of pump design, materials of construction and maintenance procedures. Data are presented for wear rates, and typical result variability is explored. To improve the availability of pumping equipment in a milling circuit it is not only important to improve the wear life, but also reduce the variability in the wear life of components so that the incidence of premature failure is lessened. Localised gouging wear due to flow separation and turbulent eddy formation is often the point at which part-holing occurs. A number of improvements to the design of pump impeller and throatbush (suction side liners) to reduce the localised gouging wear are outlined. Also, results are presented on the use of composite materials (mix of metal, rubber and ceramic) for throatbush materials to protect specific areas against wear.

Jan 1, 2012