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By R. H. McMillan

A classification of important uranium deposits which utilizes both genetic and descriptive criteria is presented. The dual aspect is useful because, while the non-genetic nomenclature for the different deposit types is amenable to various interpretations, the critical characteristics of each deposit type can be analyzed to clarify various genetic points. Although the classification is intended primarily for Canadian uranium deposits, most of the important deposit types known elsewhere can be accommodated.

Jan 1, 1978

By Richard A. Heckman

Destructive Thermal Technology (DTT) is used in the management of various waste streams. DTT includes Destructive Distillation, Pyrolysis and Classical Incineration. Recent work has more clearly defined the differences in these technologies based upon a more rigorous thermochemical approach. The U.S. Environmental Protection Agency (EPA) has chosen Classical Incineration as the Best Developed Available Technology (BDAT) for the management of hazardous organic wastes. Municipal Solid Wastes (MSW) and Sewage Sludges (SS) are also managed using Classical Incineration. Three environmental problems plague the use of Classical Incineration. Destructive Distillation, on the other hand, avoids these problems. It is an environmentally benign DTT for managing a wide variety of organic waste streams, including hazardous wastes. Thermochemical analysis of the available data on the performance of three types of DTT will be discussed.

Jan 1, 1994

By A. S. Choudhary

India is endowed with a reasonably large reserve of chrome ore, amounting to about 100 million tons in different grades and is one of the leading producers of ore/concentrate along with South Africa, Kazakhstan and others. Chromite production in India has registered a 10 times increase during the last 30 years. Till late 1940s, the practice was to mine the high-grade ore for making ferrochrome and charge chrome and export the same leaving the low and medium grade ores stacked around the mine as waste material. This practice was continued for quite some time till the increase in world wide de-mand of chromite initiated an increase in production of chromite ore in India and the aspects of ?economy of operation? and ?conservation of mineral? dawned on the producers and associated authorities. Recovery of chrome values from low and medium grade ore was initiated to produce high-grade saleable concentrate. Suitable legislation was made by Government of India to induce and provide incentives to the operators to do so. First large scale chromite beneficiation plant in India was commissioned about three decades back at Byrapore in the Southern state of Karnataka. The ore, rather simple in nature and relatively free from clay, was obtained from underground. The processing consequently was simple washing and wet tabling. Further more, some test work, on the samples from eastern coast particularly from Orissa, was carried out at an internationally reputed laboratory by a large private operator and the plant was set up. This consisted of a combination of crushing-grinding-de-sliming-classification followed by concentration in multi stage spiral concentrators and shaking table. The plant was commissioned and operated successfully. Soon a state owned company followed suit on the basis of test work carried out in a well equipped Indian laboratory. The plant worked satisfactorily after some initial teething trouble and the company plans to double the existing plant capacity by installing balancing facilities. This development prompted a number of operators, including industry leaders to join the fray and the chrome ore processing industry flourished in India. More and more operators are now in the process of adding capacities to their existing plants. This paper attempts to chart the evolution of chrome ore beneficiation industry in India through a case study with reference to an existing plant. The process technology adopted and modified to suit the altered requirements as well as the future trends are outlined.

Jan 1, 2014

"The outlook for Eastern Canada is decreased coal production and for Western Canada increased production. The market for Western coal is expected to reach 40 million tons per year in metallurgical and thermal-power markets.Technical developments in Eastern Canada include successful methane drainage experiments, modifications to the shearer-loader to improve cutting rates, mechanized mining of a tail-gate stable and mechanical stowage of level brushing. In Western Canada, the most modern equipment is used in mining, beneficiating and shipping coal. Underground hydraulic experiments were started in 1969. The importance of reclamation was recognized and plans have been made to re-vegetate disturbed areas and mine dumps.The Mining Research Centre closed the field office in Nova Scotia and is preparing to open a new field office in Calgary, Alberta."

Jan 1, 1970

By J. W. Craig

CHROME ore, which is used in Canada in the production of ferro-alloys, in a variety of refractories, and indirectly in many chemical industries, is both commercially important and scientifically interesting. The sight of chromium metal is familiar to all of us in the home, the office, the automobile. Chromium is synonymous with armaments: it is understood to be one of several essential metals in tanks, which played an important role in the defeat of France in the spring of 1940. Chromium, in other forms, comes into our daily lives by way of paint and leather, of the familiar green ginger-ale and beer bottles, and more indirectly in every pound of steel produced in the .Dominion. Necessary to our civilization in peace and war, the ores of chromium occur in many corners of the earth. This paper attempts to describe the chemical constitution of chrome ores, their world distribution, and the various chrome products and their industrial applications in Canada.

Jan 1, 1940

The SART (sulfidisation, acidification, recycle, and thickening) process is an effective way to separate copper and cyanide from each other in the waste stream of gold processing plants using cyanidation. Factorial experimentation has been conducted to create models of copper recovery, cyanide recovery, acid addition, and oxidation I reduction potential during SART. Economic analysis of the resultant models showed that SART is best operated with a sulfide to copper molar ratio of around 0.56, a pH of 4, and a minimised cyanide to copper molar ratio. The experiments also showed that thickening time may have drastic impacts on SART performance.

Jan 1, 2011

By Bertrand Robinson

Great advances have been made in rubber-lined pumps for the pumping of mill pulps. The Canadian Allis Chalmers alone report ov.er 300 such pumps put into service during the past four years. Pumps in which both the casing and the impeller are rubber covered have proved most economical in handling the usual run of mill pulps, effecting large savings in power, maintenance, and shutdown costs. For the handling of pulps containing comparatively large, sharper edged /articles, rubber-lined casings with hard iron impellers have been developed by the pumping departments of Hollinger and Noranda. These rubber-iron combination pumps show an appreciable reduction in overall pumping costs as compared with the all-rubber and the all-iron pumps. The power efficiency is lower in rubber-iron than in all-rubber pumps but higher than in the all-iron pumps, with lower replacement costs due to the cheap iron impellers used. Where continuous operation is essential, however, and duplication of units to take care of shutdown time for replacement of parts is not within the expenditure budget of the company, all-rubber pumps are being used t0 a greater extent. As in all items pertaining to milling operations, the economics of the situation must be studied as closely as the technical details, to arrive at the most advisable practice.

Jan 1, 1939

By Kris Inwood

"In 1879, when the Dominion government initiated its controversial program of industrial promotion, iron smelting in Canada was limited to one company producing coke iron on the mainland of Nova Scotia and three small charcoal blast furnaces in Quebec. There was no steel production. By the eve of the First World War, iron and steel were being produced in very large quantities, the companies active in 1879 had disappeared and new centres of integrated iron and rolled steel production at Hamilton, Sydney and Sault Ste. Marie had come to resemble the industry as we know it today. The most dramatic change was that at Sydney, Nova Scotia, where in the early 1900s, two steelmaking companies established works. The Sydney developments have been explained as the result of resource discovery and technical change. W.J. Donald, in his authoritative account of the Canadian iron and steel industry, observes:(1) ""The most rapid growth of the Canadian iron and steel industry has occurred since 1897 ... The remarkable growth has been caused largely by the new conditions of the industry. The discovery and use of Newfoundland ores, together with the availability of Cape Breton coal, has made the Nova Scotia industry not only possible but profitable .... It is a safe conclusion that the Canadian industry would not have been an important one, had it not been for the discovery of the Michipicoten and especially the Wabana (Newfoundland) ores:' Donald also argues that metallurgical progress had been necessary to render the ores valuable. ""Newfoundland ores ... contain a considerable amount of phosphorus, and were made available for steel-making by recent inventions:' The purpose of this paper is to re-examine Donald's story. It will be argued that the origin of steel-making at Sydney is somewhat more complicated than Donald has indicated. The difficulty with Newfoundland ore extended beyond its phosphorus content and a resolution required more than the basic open hearth furnace identified by Donald. Moreover metallurgical change was only one of several developments necessary to induce industrial investment at Sydney. Surprisingly, however, the discovery of iron ore in the late nineteenth century does not appear to be part of the explanation."

Jan 1, 1999

By J. Kretschmann

"By the end of the 1950s, the German hard coal mining industry produced 150 million tons of hard coal per year in 170 collieries with 600,000 employees. At that time, 70% of the primary energy demand of the Federal Republic of Germany was covered by domestic coal. However, due to coal mining becoming an increasingly globalized business and the oil and gas industry producing with lower costs, the German domestic hard coal industry stood constantly under restructur-ing pressure. The industry declined until the end of its life cycle. In 2007, a political understanding was arranged to phase out German hard coal mining in a socially acceptable manner by the end of 2018. This decision required a new strategy for the coal mining industry. Being strictly finalized, the German hard coal mining industry has to be prepared for the post-mining era. To create a sustainable development strategy, the long-term impacts of coal mining activities in Germany concerning the environmental, economic and social dimensions will be analyzed systematically and forward-looking. The regional and social responsibility during the closing process and for the post-mining era will be emphasized. High technical standards in environmental protec-tion and post-mining technologies, as well as long term experiences in the development of former mine sites to create new jobs are significant from an international point of view. The traditionally constructive social partnership between employers, union, and employees has enabled long-term stable adaption processes and avoided social friction. The sustainability strategy of the German hard coal mining industry can be regarded as a role model for other mining countries and regions facing similar transition challenges. INTRODUCTION Principally, mining is a finite business that reaches its end if the deposits are depleted or the raw materials can no longer be mined in an economically profitable way. However, the impact of mining is po-tentially an infinite one – at least if you measure it at a human time scale. Mining always means interfering with geological and ecological structures that cannot be reversed to their original condition. In general, the mining cycle (Figure 1) can be divided into three phases: 1. The exploration phase, in which the deposit is investigated to determine its technical and economic profitability. The period of these undertakings is relatively short and can lead to the launch of mining operations. 2. What follows is the actual mining phase which usually lasts for a long time and ends latest when all deposits are fully depleted. This lifespan may be shortened if the economic conditions (production cost or market price) deteriorate. Nevertheless, mining may be resumed if those conditions become favorable once more (examples are silver mining in Germany or rare earths mining in the USA). 3. The longest phase, however, is the post-mining phase as the human interference into geology and nature is usually inten-sive and irreversible. Mining can lead to consequences which have a permanently adverse impact on people and the environment; therefore, they have to be managed as best we can (1)."

Jan 1, 2017

By Ali S. Fayad

"In June 2014, Orange County Flood Control District (OCFCD) completed construction improvements of the East Garden Grove-Wintersburg Channel for a price of $42 million. Instead of the pre-existing traditional trapezoidal levee, the channel was improved with a vertical compact levee. Dubbed Soil-Mix-Sandwich (SMS), this geo-structural and environmental solution for coastal channel improvements, underlain by liquefiable soil strata, was both a design and construction innovation. It employed Deep Soil Cement Mixing (DSCM) within the confines of a hydraulically-pressed (Giken Method) sheet pile duo. SMS was unique because it incorporated both subterranean and supra-dredge-line soil mixing within a very narrow workspace. Its DSCM pattern aimed at optimum densification of the workspace and was confirmed during the construction process. It availed the DSCM sub-contractor (Hayward Baker Inc.) the opportunity to demonstrate the fitness of their huge wet-mixing machinery within a very confined access-area and introduced approximately 70,000 cubic yards of DSCM within a limited 15 foot workspace width that stretched for a mile. The sheet pile duo created a construction-enclosure that became a stay-in-place load resisting system. PROJECT CHRONOLOGY AND LOCATIONAn Orange County Flood Control District (OCFCD) project-report was commissioned to study the East Garden Grove Wintersburg channel (OCFCD facility # C05). The report examined the hydraulic conveyance of the C05 channel and was concluded in 1994 by Williamson & Schmidt. The project-report did not encompass extensive geologic studies; but it provided several alternatives for channel improvement. It recommended a single row of sheet piles as the preferred alternative for the downstream reach.The most downstream reach of the C05 channel is located in an environmentally sensitive area, in City of Huntington Beach, California, USA. Its site includes seismic chasms that surface within the C05-footprint (the Newport- Inglewood tectonic fault). Extensive deposits of liquefiable soil exist beneath the channel. Furthermore, tidal-influence prevails against the channel levee. Implementation of a successful design for channel improvement emerged after several traditional concepts were deemed unacceptable by geotechnical consultants. OC Public Works (on behalf of OCFCD) was in need of a design and construction technique that mitigated many associated risks. From these circumstances, Soil-Mix-Sandwich was born and was referred to in the rest of this discussion as SMS. OC Public Works required the SMS design concept to undergo verification by independent geotechnical consultants. SMS chronology from conception to construction can be summarized as follows:"

Jan 1, 2015

By L. R. Chimimba

"The Trojan nickel deposit occurs within a pile of ultramafic lavas subjected to a lower amphibolite grade of metamorphism. The lavas form part of the Upper Greenstones (Bulawayan Group) of the Mazoe greenstone belt. The nickel mineralization occurs as disseminated, massive and near-massive sulphides. The massive and near-massive ore occurs along the basal contact of the serpentinite units and is overlain by the more abundant disseminated ore, which occurs within the serpentinite. The main sulphide minerals are pyrrhotite. pentlandite and chalcopvrite. Minor amounts of millerite and pvrite are present. The Ni : Cu ratio in all three types of ore averages 15:1.The intercumulus nature of sulphides in the near-massive ore and similar textures occasionally seen in the disseminated ore indicates a magmatic origin of the mineralization. The basal position of the near-massive and massive ore suggests that the sul­ phides settled out under gravity during the emplacement and crystallization of a peridotitic magma. The deposit has been deformed and some of the primary massive ore has been remobilized into veins and breccias. The disseminated mineralization now occurs mainly as blebs of sulphides intergrown with silicate minerals or as stringers of sulphides between foliation planes in the serpentinite."

Jan 1, 1984

By A G. L Pratt, J R. Grant

Mining companies face the ongoing challenge of sustaining and growing production. This paper outlines business investment concepts to grow reliable returns on investment from a portfolio of choices by:improved visualisation, diagnosis and tune up of the investment pipeline (pipeline management); good corporate decision making (governance) to select the right project mix, risks and sequence; and delivery strategies to enhance and reliably execute projects.

Jan 1, 2006

By J. C. Ingram

IT SEEMS particularly appropriate that, in celebrating its Diamond Anniversary, the Canadian Institute of Mining and Metalturgy chose our Province of British Columbia as its locale in this, our own Centennial year. I am sure your organization is justifiably proud of its achievements and growth over the period of its sixty years, and we, for our part, are justifiably proud of our growth over our first one hundred years. With your kind indulgence I pro-pose to talk to you today about our industrial growth, or, to put it an-other way, to highlight, historically, our progress in industrial development over the past one hundred years, and to take the liberty of speculating on what we may reasonably look forward to over the next few years. I am sure, Mr. Chairman, that some may have questioned the appropriateness of a talk on the industrial development of British Columbia to the Canadian Institute of Mining and Metallurgy. However, strangely enough, we in British Columbia owe our origin, constitution-ally and industrially, to the mining industry.

Jan 1, 1958

By R Dimitrakopoulos, K Kawahata, L Montiel

A method that optimises mining complexes that are comprised of multiple processing destinations, open pits and underground operations is presented. Mining, blending, processing and transportation decision variables are simultaneously optimised while accounting for geological uncertainty. The method uses a simulated annealing algorithm at different decision levels to generate a stochastic-based extraction sequence and processing policies. A case study shows its ability to generate a higher net present value while facing a reduced amount of risk when compared to traditional optimisation methods.CITATION:Montiel, L, Dimitrakopoulos, R and Kawahata, K, 2014. Globally optimising open pit and underground mining operations under geological uncertainty, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 201–212 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

"INTRODUCTION In recent years, there has been increasing focus on environmental and social impacts of the extractive industries, climate change and resource scarcity. The concept of the circular economy aims to replaces the “take-make-dispose” economic model with one that eliminates waste of all kinds and is restorative by design. Such closed-loop systems implicitly aim to reduce the quantity of primary extracted materials entering the economy, thereby affecting supply and demand dynamics, hence mining industry economics. For the metals industry, the ability to engage in, or adapt to the circular economy can be heavily affected by industry structure and geographical factors. Eco-efficiency initiatives that reduce waste and environmental impact may help the mining and metals industry align with some of the goals of the circular economy. This paper focuses on base metals, and explores case studies in copper, lead and zinc. It analyzes primary and secondary metal production, and recycling. It examines company structures and how these affect engagement with the circular economy. CIRCULAR ECONOMY PRINCIPLES Ellen MacArthur Foundation (2012) describes the circular economy as “an industrial system that is restorative or regenerative by intention and design”, which “replaces the ‘end-of-life’ concept with restoration”, and “aims for the elimination of waste through the superior design of materials, products, systems, and, within this, business models”. The concept is systems focused. For materials such as metals, a series of loops are considered, including maintenance of devices, reuse, refurbishment and recycling. Potential methodologies to achieve circular economy outcomes include disassembly and reassembly of manufactured goods, leasing rather than buying major appliances, and converting to renewable energy sources. The circular economy is partially aligned with the principles of eco-efficiency, which relate to reducing the environmental impact per unit of a material produced. PRIMARY AND SECONDARY METAL PRODUCTION Base metals (copper, lead, zinc and nickel) are essential ingredients in modern economies and are key commodities produced by the global mining industry. Metal production can be categorized as primary or secondary. Primary metal comes from the processing, smelting and refining of metal content extracted from ores, while secondary production comes from metals recovered from recycled streams (e.g. recycled lead-acid batteries, copper wire scrap, etc.). Metals are stored in natural, anthropogenic in-use and anthropogenic waste stocks. An example of the stocks, flows and processes associated with global copper extraction and use is shown in Figure 1."

Jan 1, 2018

By D. E. Cameron

"INTRODUCTION Grade control requirements for base and precious metal projects are an important input to both conceptual and feasibility mine plans. It’s the author’s experience that grade control input is insufficient at these critical stages. The few exceptions are a stimulus for this paper. A significant portion of CRC’s practice has involved assisting operations to solve grade control issues which were finally recognized as contributing to negative production variances. Even in operations perceived to be successful, deficiencies in grade control are often masked by measures taken by an operation to compensate a deficiency in one area with outperformance in another. The advantages in having a realistic and adequate grade control plan developed at an early project stage by a geologist(s) with considerable operations experience are manifold. It’s important for the geologist to prepare clear inputs into the mine plan backed by detailed supporting information in usable, flexible formats. When the decision is made to advance a project, the exploration team passes its model to a mine planner. The team doesn’t usually provide a detailed grade control plan with the block model, thus the planner tends to treat grade control as an activity to be rolled into a broader operating category. The consequences of highly compartmentalized mine planning can be severe in the long run. Once a plan is tabled, and especially once production begins, it is very difficult to improve grade control outside the fixed parameters of the operation. Major fixes tend to be costly in terms of time and dollars. Implementing needed changes to the grade control practices and culture in an established mine can present almost insurmountable difficulties. Hypothetical examples of grade control planning are presented to illustrate the author’s points. The diagrams are conceptual and schematic; any resemblance to actual deposits is coincidental. BEYOND 50¢/TON In more than a few cases, grade control cost is buried in a subcategory of mining cost with little more consideration than a plugged number. It is possible to do a word search in 43-101 Technical Reports on advanced projects and without finding reference to “ore control” or “grade control”. The idea is to reach the orebody by the shortest and least expensive means, achieving production and investor payback at the earliest possible occasion. This entails a low stripping ratio pit or a decline ramp with sills on ore to prepare the first stopes. The processes to achieve the target production, one of which is grade control, will fit into this framework. After all, there is a block model and the planner can see the grade and tons in each block. The exploration geologist whose responsibility was to bring a large percentage of the deposit into mineral resource owns the model and has released it to planning. Now comes the planning stage. Mine geologists haven’t been hired yet and they will be phased in with production. What could go wrong? Larger companies may have the geologists with operating depth who will be inserted into the mine planning discussions, but it’s not a given. Junior companies must often delegate the conceptual and detailed planning tasks to consultant groups. Is a senior-level grade control review part of the scope of work for the mine planning? If a good grade control plan is in place before the mine geology team is staffed, a key element of success is assured."

Jan 1, 2018

By Oliver Bowles

The exingencies of a world war have brought home to the American public, especially the people of the. Eastern States, the urgent need for conserving fuel. Transportation problems in the East have created an unprecedented situation wherein fuel-oil supplies are greatly restricted, and the consequent increase in demand for coal further complicates the problem of transporting and storing that commodity. People should awaken to the need for utilizing every possibly means of conserving to fuel, even to the extent of reducing the temperature in their homes.

Jan 1, 1942

Is your company paying taxation on profits which are partly illusory?ò Are unions making wage demands based on erroneous notions of the real level of value added to your companyÆs production?ò Do you receive historic data on profit contributions by different products, or for different market areas, which you feel may be misstated?ò Do you find that cash is not always readily available to pay dividends out of reported earnings because, it is required to finance additional working capital without a real increase in the level of activity?ò Are your planning and budgeting routines hampered by the need to rely on historic financial data which bear little resemblance to what the future may hold for your company?ò Are you able to maintain your business at its optimum operating capability or do you feel each year that it becomes more and more difficult to achieve the same volumes of prdduction at the same level of return on assets employed without having to raise more capital?If your answer to any of these questions is "yes", then it is very likely that Current Cost Accounting (CCA) has something to offer you!characteristics of the mining industry and for single venture mining operations.

Jan 1, 1984

By Leon E. Laforest

An early commitment by Kidd Creek Mines Ltd. (formerly Texasgulf Canada) to follow a stringent environmental control programme from the initial stages of design and development of its metallurgical facilities in Timmins, Ontario, has resulted in the on-going attainment of extremely low levels of industrial waste emissions. This paper outlines the monitoring programme initiated and maintained by the company's environmental control section. Comparative results of environmental sampling for the periods before and after the copper smelter start-up are highlighted.

Jan 1, 1983

By T. A. Rickard

Freeman, the English historian, said that he had learned from Macaulay "never to be afraid of using the same word or name over and over again if by that means anything could be added to clearness or force. Macaulay never goes on, like some writers, talking about `the former' and `the latter', `he', `she', `it', and `they', through !clause after clause, while his reader has to look back to see which of several persons it is that is so darkly referred to". He might have learned also from Macaulay that a preposition makes a' feeble ending for a serious statement. How often do you hear `the former' and `the latter' in conversation? Good conversation is a guide not to be dis¬dained. When you must use `the latter', do not confuse it with `the last'. Cheap labor, cheap fuel, and cheap transport are essential, the latter [last] being particularly important in base-metal mining. The apparatus may be used to determine such gases as hydrogen sulphide, chlorine, oxides of nitrogen and some others, as well as sulphur dioxide. In the case of the latter two, etc. The two last mentioned are "sulphur dioxide" and "some others". He should have stated which two, and he should have avoided that wretched phrase "in the case of ". Pinning may be partly prevented by use of chalk, oil, or turpentine. The latter [last] is best. I "Partly prevented" is a poor phrase. `Prevented! is a word that does not lend itself readily to modification. He means `checked' or `corrected'.

Jan 1, 1931