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By Robert B. Parsons

"Canada doesn't really have a tax system for mining - it has eleven separate tax systems! The consequent maze adds some undefinable margin of difficulty to making investment decisions in Canada. But, this 11U1Ze is not likely to be simplified. Solution: learn it and sell it! Intricate Network of Winding PathwaysWebster's New World Dictionary defines the word ""maze"" as follows: ""a confusing, intricate network of winding pathways; labyrinth ... a state of confusion or bewilderment"". Webster's does not go on to give an example of a maze, but the dictionary could easily have referred to the taxation of a Canadian mining operation. The uninitiated would almost certainly look upon such taxation as a maze of the most perplexing sort.Twenty years ago, Canada's tax system was really quite simple. It is true that Canadian mining profits were subject to three levels of taxation (federal income tax, provincial income tax, and provincial mining tax), but this didn't pose a problem. Prior to 1974, at least the provincial income tax systems were somewhat the same in terms of rules .and rates, and even the provincial mining tax systems resembled one another. Mining profits were subject to pretty much the same rules, no matter what province or territory hosted the mine. Those were the “good old days” one could even dare to generalize about tax rates without fear of being labelled an imbecile!"

Jan 1, 1994

By Juliana Parreira

The past decade shows record increases in global demand for minerals and metals with an accompanying significant decline in skilled personnel. Mining companies today are examining new technologies to maximize production, reduce costs, and create safer work conditions to deal with this shortfall. Automation of an open-pit mine haulage system is receiving attention as a beneficial option since it provides more consistent and efficient operation of mining equipment, it removes workers from potential danger, it reduces fuel consumption significantly reducing greenhouse gas (GHG) emissions, and it can help optimize vehicle repairs and equipment replacement because of more-predictable and better-controlled maintenance. This paper describes a simulation model under development using the EXTENDSIM software package to examine scale-up issues and constraints of autonomous vehicles in comparison to a manual system. The software can predict and manage Key Performance Indicators (KPIs), such as productivity, safety, cost, equipment failures, fuel consumption, and tire wear under different road and load conditions. By breaking-down the various systems of an autonomous haulage truck and simulating the overall haulage system using a Monte Carlo approach, the model becomes a flexible and powerful tool to use within a mining organization. Direct comparison to a manuallyrun system can be done to show the cost and operational benefits of automation. Project managers can use this tool to guide decision-making about possible application of autonomous haulage trucks at a specific mine site.

May 1, 2010

By Brien A. Perry, Art Wiebert

"Many organizations which have implemented Total Quality Management (TQM) are finding that the process has either stalled or is not working so well as originally envisioned. This can be particularly evident in an engineering environment where the uniqueness of engineers and their particular culture has not been adequately considered. Winning the commitment of a highly educated group ojprojemnnJJ1s to the TQM concepts, which are often initially 5W2 as too simplistic poses special challenges.Successful TQM implementations are found among technical groups where employees have significant input into creating the new work culture, feel empowered to make changes and are well trained in teamwork. A coach who is knowledgeable in implementation problems can, when working closely with the technical teams, help them circumvent obstacles and guide them successfully through the difficult early phases. The remaining key ingredient for success is supportive management which leads the change and is both informed and appreciative of the accomplishment being made.This Paper is based on first-hand experience with common problems and results encountered in implementing TQM in an engineering environment. Described in the paper are ways of avoiding these problems through awareness of the unique nature of engineering groups, implementation planning, just-in-time training and coaching people in the TQM process. The paper concludes with a focus on the opportunities and results from a successful implementation. These opportunities and results include the benefits each engineer can realize through process thinking, empowerment and teamwork."

Jan 1, 1995

By M. Takebayashi, M. Shingu, H. Nagai, T. Nakai, S. Asano

The Toyo Smelter and Refinery, owned by Sumitomo Metal Mining Co., Ltd. (SMM) is located in the coastal zone of Saijo City and Niihama City, Ehime Prefecture, Japan. The refinery has been producing copper, sulfuric acid, and precious metals such as gold, silver, and PGMs. Previously, the process of precious metals recovery was a combination of pyrometallurgy and an electro-refining process with the conventional cupellation for around 400 years. However, this process had some major problems such as non-efficient recovery of valuable metals, high environmental risk by pyrometallurgy, high cost for maintenance of equipment and so on. In order to solve these problems, a thorough hydrometallurgical process for precious metals refining using chlorine leaching technology was originated and developed by Sumitomo and thereafter commercialized in 2004 at Toyo Copper Smelter and Refinery. This new process enabled shorter-term recovery of gold and manpower saving, and occupational safety and working conditions have also been improved. Superiority over the existing hydrometallurgical processes was also confirmed, for example by the achievement of 99.99% pure silver production without an electro-refining process. This paper summarizes the hydrometallurgical technologies for precious metals recovery such as chlorine leaching of copper anode slime for silver recovery, solvent extraction (SX) for gold recovery, and ion exchange (IX) for PGMs recovery. It also presents a unique silver purification process. INTRODUCTION Sumitomo Metal Mining Co., Ltd. (SMM) produces copper, precious metals and rare metals as by-products at the Toyo Copper Smelter and Refinery, and nickel and cobalt at the Niihama Nickel Refinery. Precious metals contained in nickel ore are also separated and refined at the Toyo Refinery after concentration. SMM has been refining precious metals using the pyrometallurgical method. In recent years, we have revamped the separation and refining process of precious metals dramatically by making use of advanced hydrometallurgical and engineering technology developed in the company. In this paper, we introduce the history of development and techniques of this process, and also introduce in detail the technologies of gold refining, PGMs recovery, selenium recovery, and silver refining which have been particularly difficult to achieve.

Jan 1, 2019

By Jaeheon Lee

"Biooxidation of gold ores or concentrates could be a very attractive alternative to pressure oxidation (POX) or roasting to liberate the gold grains from various sulfides. Crushed heap bioleaching was successful in US and many operations using tank bioleaching of gold concentrate are currently running around the world. Many parameters need to be considered during the project of sulfidic refractory gold ore process. Capital and operation costs are among the most important ones. Run-of-mine heap biooxidation could be very inexpensive and the smaller the crush size (particle size), the more expensive the capital and operating costs for biooxidation application are expected. The capital cost of biooxidation could be a fraction of the cost for building POX plant or roaster and the operating cost could be 1/3 of POX or roasting depending on the method utilized. A new biooxidation process, Sand Farming, is introduced as an alternative to POX and tank biooxidation process. A relatively coarser particle size (P80 = 650 µm) of the process benefits the low cost of grinding against the conventional grinding size (P80 = 75 µm) for other options. The cost of Sand Farming is less than 40% of that of pressure oxidation with comparable gold recovery from the downstream process. This paper will review the laboratory scale testwork for various biooxidation process of sulfidic refractory gold ores and concentrates and provide the economic evaluation showing the biooxidation could be the most economic method without much sacrificing the overall gold recovery. INTRODUCTIONThe decreased availability and lower grade of raw materials has motivated industries to consider recovering values utilizing low cost process options. The process may treat high grade concentrates or submill grade ores that cannot be processed economically by conventional milling-flotation or leaching. Sulfidic refractory gold ores/concentrates have been economically processed by roasting, pressure oxidation, and biooxidation in stirred tank reactor. The process selection is based on a series of studies including multi-year long ore characterization and metallurgical investigations."

Jan 1, 2016

By A. Gakwaya, P. Vachon-Joannette, P. Gagnon, J. Lévesque

"Predictive numerical methods are essential tools for reduced development cost and improved high performance designs of modern aircrafts. Their use leads to savings in terms of design cycle time and experimental trials. Composite materials subjected to impact loadings demonstrate various damage modes such as matrix cracking, fiber breakage, delamination and, ultimately, fabric fracture. Composite laminates are extensively used in the aerospace industry, and their damage modeling is complex due to their inhomogeneity and anisotropic behavior. Damage evolution affects both in-service properties and performance of these composites. In this work, the drop-weight impact test has been simulated. Using a material model that accounts for both delamination and intralaminar damage, laminates response is analysed using numerical simulations based on 3-D finite-element models of the commercial code Abaqus/Explicit. Experimental and simulation results are compared, in terms of energy absorption and contact force. The obtained numerical results show good agreement with experimental data.INTRODUCTIONAs primary aircraft structures are increasingly being made from advanced fiber-reinforced polymer matrix composites and are in general exposed to a variety of impact scenarios (bird, hail, debris etc.), an understanding of the impact event and the performance of composite materials during impact is important in the development of new structures. This work is focussed on low velocity impacts that typically occur when foreign objects hit the aircraft during maintenance or other on-the-ground operations. These impacts can cause non visible damage that affect the structural integrity of the composite components. While for metallic structures, damaging impact events typically leave noticeable dents due to plastic deformation, in contrast, for high strength carbon fiber reinforced composites, they can deform elastically to strain levels exceeding 1% and the internal damage can often occur without the formation of a visible dent. The identification and effect of impact damage on the performance of the structure is thus of great concern to the aircraft industry as the durability and damage tolerance of these composite structures are strongly influenced by the size of detectable internal damage."

Jan 1, 2016

By R. T. Erskine

"IntroductionIn this paper it will not be possible to cover all details of the reagent systems at Brunswick Mining and Smelting but it is hoped that a description of the evolution of these systems will be of some benefit. The concentrator of Brunswick Mining and Smelting located near Bathurst, New Brunswick was originally designed as a 3,000 ton per day operation but before construction commenced was uprated, with 4,500 tons per day being treated by the summer of 1964. Development of the open pit at another ore body five miles away was initiated in 1965 and additional concentrator and crusher facilities went into operation in September, 1966. Present total daily throughput is over 8,000 tons per day. The ore at Brunswick is very high grade but mineralization is very fine grained and requires grinds generally over 75% minus 400 mesh for liberation. The amount of surface exposed using grinds of this order understandably requires great quantities of reagents, Reagent mixing systems for the original concentrator allowed only for batch mixing and were very expensive in labour cost especially.During the first three years of operation total number of men employed in reagent handling reached a peak of four men per shift and six men on dayshift unloading cars for a total of 22 men. At present only one man is employed on shift, and four men on dayshift take care of unloading and mixing reagents, a total of 8 men. The man on shift is almost entirely occupied with checking feeder operation, flow rates, and head tank levels. Most commonly used reagents are tabulated in Fig. 1 showing average monthly and daily requirements in the Brunswick operation as well as pounds per ton of mill feed as found in 1969. It is very obvious that with over seventeen tons each of lime and soda ash and six tons of copper sulphate used each day, opening of bags and mixing batches of solution is an inefficient undertaking."

Jan 1, 1970

By Malcolm Scobie

"This paper reviews the evolution of Canadian surface and underground mining automation, principally relating to: advances in communications, initial development of machine teleoperation from line-of-sight remote control, and islands of automation. The eventual role of teleroboties and minewide robotic mining remains to be resolved. The progress and approaches adopted have tended to vary within each sector of the mining industry. Recent information technology advances have made possible the Digital Mine; in which information associated with all mining processes, however dispersed, would be integrated with support systems using new communications technology. The Digital Mine will provide the information infrastructure to serve as the foundation for minewide automation. This paper concludes by reviewing the issues likely to govern implementation success, relating to: mining process design, machine design, machine intelligence, and mine planning and control.IntroductionSignificant advances have recently been made in underground hardrock mine communications and teleoperation. Subsequent R&D efforts are mainly focussing on control systems for various types of machines. In underground potash mining, the realization of automated continuous mining systems appears to be imminent. Recent advances in surface mine dispatching, machine monitoring and global positioning systems (GPS) have tended to reactivate some of the initial R&D enthusiasm developed in the '70s for surface mine automation. Mines at large are approaching a major milestone: the implementation of comprehensive communications infrastructure which proves to be sufficiently reliable and economical to support the automation of routine mine production, either using teleoperated or autonomous machines. This then should motivate a deeper commitment to real time monitoring and management. The communications advances make possible the Digital Mine; in which information associated with all mining processes, however dispersed, would be integrated with support systems using information engineering. The Digital Mine will provide the information infrastructure to serve as the likely foundation for a wide range of automation scenarios. This paper surveys the status and directions of automation development in both surface and underground Canadian mines, pointing to what are seen to represent key technology development issues."

Jan 1, 1995

By Robert B. Parsons

"While it might seem like heresy to suggest that ""taxation"" can be a source of financing, never the less some generous tax rules can considerably enhance the tax savings pertaining to a particular expenditure or project. A basic tax knowledge, and careful tax planning, can optimize government participation in a project. INTRODUCTIONIn trying to identify sources of financing for a project, ""government"" as a source of funding is normally thought of in terms of government grants, loan guarantees, interest rate buy downs, property tax waivers, hydro subsidies, and so on. Generally, such concessions are somewhat difficult to obtain, especially in the current period of apparent fiscal restraint. One source of government funding which should not be overlooked is the income tax regime, and, at the provincial level, the various provincial mining tax regimes.While the taxpayer would not normally view a tax system as a potential source of government financing, nevertheless various federal and provincial rules applicable to the mining industry can offer attractive tax deductions - and tax savings - with respect to particular expenditures. In fact, it is not unusual for a civil servant to refer to a tax deduction as a tax ""subsidy"". For example, in the right circumstances, the cost of a smelter expansion in New Brunswick would cost the operator only 31 cents on the dollar, with the federal and provincial governments paying for the other 69 cents by foregoing tax revenues (Table I). In a sense, such tax savings could be compared to a government grant equal to 69% of project costs. Of course, not every project expenditure will generate that degree of government funding. The fact of the matter is that the percentages of tax savings attached to different expenditures cover a wide range, depending on a complex mix of factors. The point to understand is that the tax rules can offer some valuable savings, even after tax reform, and that a basic knowledge of the tax rules can yield some fruitful rewards."

Jan 1, 1989

By P. A. Mascaró, N. Chacon, A. A. Cecchi

"This document shows the development of a system called the “On-line charge level determination in SAG mills” (abbreviated as Jc). The Jc variable has certainly been difficult to measure due to the relevant number of factors and variables that affect the grinding phenomena inside semi autogenous (SAG) mills. To assess the feasibility stage of the proposed system, it was necessary to carry out two tests in different sized SAG mills, 38´ × 22´ and 36´ × 15´, respectively. In each test, the system was configured with a battery of sensors of the following types: (1) strain gauge, (2) accelerometer, and (3) gyroscope. The first step involved for charge level determinations was to determine kidney foot and shoulder by means of a study of the energy-impacts on shell structures. The second step consisted of correlating the measured grinding operational variables with the actual charge levels obtained from SAG mill crash stops. This system development is extremely useful and relevant for providing approximations about mass balances inside SAG mills. It will be a suitable tool for explaining “tonnes per hour” variations and determining optimal points under various operating conditions.INTRODUCTIONThere has been a growing necessity for technologies capable of obtaining “on-line data” of the main comminution variables in order to increase throughput. Computer systems have taken an important role in providing important solutions by means of processing on-line device signals (commonly referred to as monitoring). In semi autogenous (SAG) milling, there are many examples of monitoring devices that allow the operational staff to obtain detailed information both mechanically and electronically inside a grinding circuit. In this context, a new technology has been developed to obtain “Jc total charge (%) online” in two different SAG mills called Vibro-Energy® System.As part of the analysis performed by JKsimMet® the Jb/Jc was estimated because it has an important impact on SAG mill throughput. Different scenarios were simulated and contrasted at various theoretical Jb/Jc values in a baseline circuit (Figure 1)."

Jan 1, 2016

By Dr. Rory Cameron, Dr. Terry Cheng, Dr. Nadia Mykytczuk, Ian Bedard, Kristie Tarr, Ruth Joseph

Pyrrhotite-rich tailings from Sudbury, Ontario mining activities are known to contain significant amounts of EV metals, such as nickel and cobalt.  CanmetMINING has developed a novel bioleaching process for recovering the nickel and cobalt (both critical for vehicle electrification) from tailings that incorporates partial neutralization and iron removal in the bioleaching circuit; bench- and pilot-scale tests have resulted in excellent nickel and cobalt recovery over a range of temperatures.  However, this process generates a new bioleach residue, which is heavier and more voluminous than the original tailings due to pyrrhotite oxidation and jarosite formation during the bioleaching process. This residue can be problematic for long-term disposal. A possible solution being studied for this issue is using mine backfill as a disposal mechanism.  Underground backfilling allows for effective re-purposing of mine waste, however the backfill must also be able to withstand a certain load, since in most cases it is used as an underground construction material, such as in cut-and-fill mining methods.  Therefore, the composition of the mill tailings must be such that when combined with a binding agent and pumped underground, the slurry or paste is then able to withstand a certain load within a certain period of time.  Unfortunately, high-pyrrhotite content tailings, commonly found on mine sites in Ontario and Quebec, are reactive and can easily oxidize and produce acidity and/or metal-laden drainage under some disposal conditions. This means that the pyrrhotite in the tailings can lead to acid mine drainage if stored on surface, however, it can also cause strength degradation if re-purposed in too high a concentration in underground mine backfill.  The research being done at CanmetMINING related to the bioleaching process is aimed not only at recovering nickel and cobalt from mine tailings, it is also being used in an attempt to neutralize the tailings to reduce acid mine drainage and backfill strength degradation. This paper reports on research designed to evaluate different options for transforming the bioleaching process residue into iron oxide phases, for better environmental footprints if stored on surface, as well as increased disposal possible, if re-purposed as underground mine backfill material.  

May 4, 2025

By I. Silin, M. Stapelmann, H. Wotruba, K. M. Hahn, C. Gerold, J. Katzmarzyk

New deposits are often characterized as low-grade and complex ore bodies. To date, processing of fine grained ore deposits implies complex processing routes with high energy consumption. For that reason, the investigation of dry grinding, e.g. with vertical roller mills (VRM), is an approach to save energy reserves. It is already proven that dry grinding can influence subsequent processing steps. In terms of flotation, the surface characteristics of the minerals are crucial for a successful flotation process, e.g. the sufficient adhesion of mineral particles and air bubbles. Wet grinding results in different surface properties of the product entering the conditioning stage than dry grinding, which has direct influences on the subsequent flotation process. To investigate the consequences for flotation, processing of a copper sulfide ore containing chalcopyrite and bornite was investigated, including grinding and rougher flotation. The effects of wet tumbling mill and dry VRM grinding on the degree of liberation of valuable minerals are characterized using mineral liberation analysis by scanning electron microscopy. The obtained flotation results, as well as the recorded flotation parameters such as dissolved oxygen, oxidation reduction potential and conductivity are presented and discussed. INTRODUCTION Copper production is mainly connected to porphyry copper deposits as main source for copper sulfides such as chalcopyrite and bornite. State-of-the-art processing of these deposits is already established worldwide for decades, combining crushing, fine grinding and subsequent flotation with rougher, cleaner and scavenger stages (del Villar, Desbiens, & Maldonado, Bouchard, 2010). While the demand for copper is increasing, copper grades of the deposits are decreasing and the remaining ore bodies have more complex mineralogy and finer particle size distribution. This implies processing routes with high water and – due to the liberation of fine grained valuable minerals – high energy consumption by fine grinding. One of the main energy consumers in processing plants is the grinding section, which accounts for more than 50% of the energy consumption in processing plants and even 4% of the worldwide energy consumption (Jeswiet, & Szekeres, 2016). Therefore, dry fine grinding alternatives are applied to enhance the overall energy consumption of mineral processing plants: high pressure grinding rolls (HPGR) and vertical roller mills (VRM).

Jan 1, 2019

By Richard W. Herzer

Introduction Thermal methods have been predominant in the metallurgy of the base-metals ever since the foundation of the industry thousands of years ago. Development in hydrometallurgy has been confined largely to the past six or seven decades. It was at first necessarily slow, then for a number of years rapid progress was made. At present, the uncertain state of the metal industry has curtailed research on the subject; however, in the next few years one may assuredly look forward to an ever increasing use of wet processes. Leaching methods have attained the dominant position in the case of certain metals, notably zinc. For others, they have made no headway at all. Copper presents a situation all its own. Due to the varied nature of its ores and to the large number of localities in which it is mined, a great number of processes have been developed, each suitable in its own particular field. In the case of this metal, therefore, it is more difficult to arrive at definite conclusions. It is the purpose of this paper, first, to review the outstanding developments of base-metal hydrometallurgy, and, secondly, to consider possible Canadian applications of some of the processes in use. The discussion will be confined to the three metals, zinc, lead, and copper, with particular reference to the last mentioned. Zinc General Note At present, zinc is produced by two principal processes, the older retort process and the electrolytic process. The latter is a development of the last twenty years and, judging by its present progress, bids fair eventually to supplant older methods in a large proportion of cases. It is certain, at least, that in the erection of a new plant, a hydrometallurgical process would be given the most serious consideration

Jan 1, 1934

By A. Atef

Vulnerability is a measure of the extent to which a community, structure, services or geographic area is likely to be damaged or disrupted by the impact of particular hazard. Current asset management practices focuses on studying factors that affect performance of isolated infrastructure networks and model a set of actions to control the expected performance of these networks. This approach ignores the underlying spatial and functional interdependencies among these infrastructure networks and their vulnerability. The purpose of this paper is to introduce a new method that recognizes the effect of spatial and functional interdependencies on vulnerability rating of water, sewer and road networks. The proposed method consists of: 1) risk assessment model, 2) interdependency assessment model and 3) vulnerability assessment model. The risk model is composed of two modules: 1) water and sewer risk module and 2) road infrastructure module. The water and sewer risk module will cluster these assets into three risk categories based on environmental, social, operational and economical factors. The road infrastructure module will cluster road assets into three risk categories by using rational factorial technique based on road type, serviceability index, traffic load, and freeze and thaw index. The interdependency model will deploy the risk ranking to perform geospatial analysis in ArcGIS which results in determining the interdependent layers of waters, sewers and roads. The vulnerability model will deploy fuzzy neural networks technique to determine the vulnerability rating based on spatial and functional interdependencies. The fuzzy neural networks are utilized to overcome the lack of historical data and incorporate experts? preferences for establishing the knowledge base for vulnerability assessment. The expected contribution of this framework is to aid decision makers in understanding the interdependencies between civil infrastructure assets and to which extent such interdependencies can compromise assets performance.

Aug 1, 2013

By A. Y. Senchenko, S. G. Rybkin, A. V. Aksenov

In gravity processing of gold-containing ore the target produced concentrate which is high gold grade primary concentrate contains a significant amount of cassiterite (SnO2). The plant attempts aiming at concentrate processing using a standard pyrometallurgical technology did not provide any positive results. The present paper is dedicated to development and testing of improved technology for pyrometallurgical processing of rich gold primary concentrate with high cassiterite content. According to material composition study primary concentrates produced at the plant contained 1.5–2.0% Au, 0.1–0.3% Ag, 55–65% SnO2, 20–25% Fe2O3, and 10–15% Fe3O4. The developed technology included alkaline nodulizing of primary concentrate mixed with sodium hydroxide and carbonate at 350–650°? with cake production. In blend nodulizing stannum and iron passed into sodium stannate (Na2SnO3) and sodium ferrate (NaFeO2) respectively. The blend of cake and fluxing agents was smelted at 1,150–1,200°? resulting in dore gold and slag production. Sodium stannate with 360°? melting point is well dissolved in slag system Na2OSiO2- B2O3-CaO. During plant tests 18.5 kg of high gold grade primary concentrate were processed, 1350 g of dore gold and 75 kg of slag were produced. Dore gold contained 16.5% Au, 0.95% Ag, 78.0% Sn, 3.1% Fe. Slag contained 12.4 g/t Au, 6.7 g/t Ag, 9.8% Sn, and 5.6% Fe. Gold recovery to target alloy was equal to 99.58 %, 87.8% of Sn passed into slag. This new technology was accepted for application at the plant.

Jan 1, 2016

By R. J. Brailey

"A USER'S VIEW OF CONVEYOR WEIGH SCALESThe Sudbury Operations of Falconbridge Nickel Mines Limited includes seven mines, three concentrators and a smelter. The flow of ore, concentrates, fuel and fluxes between and within these plants requires measurement for accounting and control. The design, installation and maintenance .of weighing systems falls within the responsibility of the Instrumentation Department of Falconbridge Nickel Mines thus al lowing a common approach to conveyor weighing problems and the benefit of a common spares supply. This paper gives a brief overview of the recent experience with conveyor scales within the Sudbury Operations and discusses the problem areas.GeneralThe best way to establish the total amount of material going to or from a process is with a bucket and a stop watch. Unfortunately the flowrates involved in mining plants make the buckets very large, but wherever it is feasible static weighing is the preferred method of determining total quantity. This applies particularly to batch systems, where the material can be brought to rest long enough to allow a very accurate weight determination. Any form of weighing in motion is susceptible to variations in the forces of the transporting system. A belt scale is affected by its position on the belt, idler alignment, support stiffness, variations in belt tension, material spills and build-up, and a host of other factors all of which require careful consideration in any installation.As with instrumentation applied to any system the plant should be designed to ensure that the best results can be obtained from the equipment. This means getting the scale supplier together with the conveyor supplier as early as possible in the designing of a new plant. Any corners cut in scale installation will be paid for later in poor results and/or increased maintenance."

Jan 1, 1975

By Georges Houlachi, Akram Alfantazi, Michael Mahon, Maysam Mohammadi

Corrosion resistance of the lead-based anodes directly influences the purity of the final product in the zinc electrowinning process. The anodic MnO2 layer that is electrodeposited on the anodes during this process can protect the anodes against corrosion. Sand-blasted anodes generate a uniform, adherent and shiny MnO2 layer, which gradually blisters and eventually sloughs off after several weeks. In this study, we attempted to develop a new method to stabilize the MnO2 protective layer on the anodes during the electrowinning process by providing suitable nucleation sites for electrodeposition of this layer. MnO2 particles (P80=40µm) were used as seed material for this purpose. Different techniques of galvanostatic and cyclic voltammetry polarizations, scanning electron microscopy (SEM) and atomic absorption spectroscopy (AAS) were employed to investigate the performances of the MnO2-seeded lead anodes. The experimental results showed that growth of the MnO2 layer is influenced by the MnO2 seed particles on the anode surface. The MnO2 layers electrodeposited on the MnO2-seeded lead anodes were uniform and strongly adherent to the substrate. This layer was more stable than those formed on the PbAg anode without MnO2 seeding. This could provide the anode with a higher level of corrosion protection. Moreover, formation of undesirable MnO2 mud in the electrolyte and the rate of manganese consumption were decreased when the MnO2-seeded lead anodes were polarized. These observations could be attributed to the different properties of the electrodeposited MnO2 layer on this anode in comparison with that formed on the PbAg anode.

Jan 1, 2016

By J. L. Bowlby

OWING to the pressure of routine analyses at the laboratory during the past year, work of an investigational nature on water problems has been greatly curtailed. Favourable reports by the boiler inspectors indicate that the operators are giving satisfactory attention to feed-water treatment at the several . power plants. Some of the operators prefer lime and soda, others the phosphate and soda treatment. Springhill is still on the same commercial treatment as they were using last year, and satisfactory results are being obtained. This individual preference for a particular treatment, although it may be different for feed waters of similar nature, indicates that so long as proper conditions of alkalinity and concentration are maintained within the boiler, it is immaterial what chemicals are used in the treatment. This statement refers, of course, to the low-pressure boilers. In high-pressure boilers, a treatment such as lime and soda cannot be satisfactorily employed, on account of the precipitated calcium carbonate unduly increasing the amount of suspended matter. Only one case of impending trouble was reported during the year. That was at Seaboard, shortly after the new unit was placed in operation. Dissolved oxygen, considerably in excess of the permissible 0.030 cubic centimeters per liter, was detected at various points on the feed line. It was suspected that a de-aerating heater was being operated at too low a temperature, and chemical tests, made before and after the necessary adjustments, proved that this was the source of the trouble. While it has been impossible to give mine waters the attention they require, progress can be reported in the work carried out by the Mechanical Department. Past investigation of the action of mine water on various acid-resisting alloys is now bearing fruit, and it can safely be said that repair work on mine pumps has been reduced by nearly one-half.

Jan 1, 1938

By D. P. Wilkinson

There are significant global environmental and supply issues with existing energy paths today . Global emission and fuel regulations, global fuel and power structure, energy security, and cost are driving new technology and non-conventional approaches . Fuel cells will play a significant role in the strategy to effect positive global change, increase fuel efficiency and decrease dependency on traditional fossil fuels. Fuel cells do not require recharging, just refuelling and a wide range of fuels are possible with hydrogen being the most desirable. Technical progress as well as investments in fuel cells for transportation, stationary, portable, and micro fuel cell applications have been dramatic in recent years. The present view is very optimistic for fuel cell power generation and the status is presently at the field trial level, or early commercialization stage, moving into volume commercialization. A number of demonstration programs are in progress worldwide such as the California Fuel Cell Partnership which involves original equipment manufacturers (OEMs), fuel providers, transit authorities, state and government bodies. Fuel cells and a hydrogen infrastructure are key to a long-term solution to global energy issues. Fuel cells will need to be competitive on an economic basis with the established and highly developed internal combustion engine and other forms of power generation There has been significant technical progress in a number of fuel cell areas including power density, transient / dynamic response, multiple fuels, cost potential, reliability and durability. However, significant technology gaps still remain today. This presentation will focus on the status and progress of the fuel cell today, current fuel cell research and development, the challenges going forward, and the future view of the fuel cell and it's impact on global energy issues.

Jan 1, 2005

By R. A. Rabnett, G. Paget, Patrick Walsh

"Tumbler Ridge, Canada's newest resource community, has been developed differently than have been other resource communities.Since its conceptualization, emphasis has been placed on the establishment of a traditional municipal government at early a stage as possible.Planning f or the community goes back to 1977. By then, extensive study by provincial agencies had shown a new resource town would be required to exploit north east coal. The Ministry of Municipal Affairs, in conjunction with a consultant named R.A. Rabnett began the extensive Tumbler Ridge conceptual plan.The results of the conceptual plan are evident in the organizational and planning goals of Tumbler Ridge. In every aspect from the election of officials to some financial matters, the town functions as a normal municipality. With the resource companies of the North East Coal Development within its municipal boundaries. Tumbler Ridge has been able to debenture its capital projects against its municipal tax base.The town's ability to function as a normal municipality is enhanced by its control over Crown land it has purchased from the province. This gives it further control over the development of the community and helps in establishing agreements with the resource companies and the provincial government to ensure that housing and service needs are met. While resource company representatives sit on certain municipal committees, their roles are advisory in nature.The community continues to move toward full municipal status and will have a fully elected Council by 1986.BackgroundPlanning for the development of northeast British Columbia coal resources began in 1976 under the aegis of the provincial Cabinet Committee on Coal Development. A series of subcommittees were established including a Townsite/Community Development subcommittee. The Ministry of Municipal Affairs chaired this subcommittee and continued as the lead agency for the provincial settlement planning effort over the period 1976 to 1981."

Jan 1, 1983