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By K. Dinh

The Ground Penetrating Radar (GPR) has been studied for a long time as a non-destructive evaluation (NDE) technology for inspection of concrete structures. Currently, the most widely used technique for interpreting GPR data of concrete bridge decks is the one that based on the amplitudes measured at various interfaces such as asphalt-concrete, top rebar, or slab bottom. The assumption behind this technique is that a sound concrete deck should have the same reflection amplitude at these interfaces while any low number would indicate some sign of deterioration. Unfortunately, this assumption is not completely valid in most cases. As a consequence, the reported test results usually do not reflect real condition of concrete bridge decks in question. The main goal of this paper is therefore twofold: (1) to discuss the limitations of the amplitude analysis method, and (2) to propose a new model that interprets GPR data of concrete bridge decks. The model methodology is based on the comparison of GPR A-scans between two inspections, using the so-called correlation analysis. The results, indicated by the correlation coefficients, are then employed to develop a contour map that estimates different levels of deterioration. The model is then implemented to a case study in order to illustrate its methodology.

Aug 1, 2013

By Clemens Kuhnert

"Nickelhütte Aue GmbH is specialized in the recycling of waste materials containing non-ferrous metals. We treat nickel, copper, cobalt, vanadium, molybdenum and precious metal containing materials like spent catalysts, ashes, dusts, grindings, liquids, slurries and sludge's as long as they contain one or a combination of the above mentioned metals. In our pyrometallurgical works we produce non-ferrous metal concentrates suitable for further treatment in our hydrometallurgical plant where we refine Ni-, Cu-, Co- and V-chemicals. Our production is based on synergy effects due to the combination of pyro- and hydro-metallurgy. As an example we can mention our heat recovery system and internal recycling of by-products. Furthermore, the use of alternative fuels instead of fossil fuels contributes to the economic and environ-mentally friendly treatment system.INTRODUCTION Nickelhütte Aue GmbH (NHA) can look back on nearly 400 years of tradition as a pyrometallurgical works and recycling company. The existence since its foundation in 1635 as a blue dye works shows responsible and successful action in the past. Therefore, we see highest customer service, minimization of interferences with nature by closing material cycles and maximized health and occupational safety protection by avoiding injuries and diseases, still as our future duties. These duties are evaluated and monitored by an integrated management system that meets the standards of DIN EN ISO 9001, 14001, 50001 and BS OHSAS 18001. We commit ourselves to the observance of all juridical and customized demands. The management and the department managers perceive their model function. We require responsible action from all employees. To protect the continuity of our enterprise, we will also perform in future continuous improvement of products and their quality, as well as steady progress in the areas of environment protection, health protection and industrial safety. Equally the effectiveness and propriety of the management system is checked and developed regularly. In order to obtain the objectives resulting from this policy, our company determines activities and measures by involving all employees."

Jan 1, 2017

By Rodgers Peale

The Waite mine, as it is locally termed, is situated in the Rouyn district, in the townships of Duprat and Dufresnoy, Quebec, and lies about 340 miles north of Toronto. Due to the impetus given prospecting in the Rouyn district by the discovery, some years ago, of copper-gold ore on the Horne claims, many exploration parties were put into the field. Early in 1925, J. H. C. Waite, C. H. Ackerman, and T. Montgomery staked the claims which now comprise the mine beating their names. Trenching and diamond drilling soon disclosed an ore-body of commercial size and grade, and by the end of 1928 a shaft had been sunk 300 feet and the mine was producing 150 tons of direct-smelting copper ore a day. In the summer of 1925, Dr. H. C. Cooke, of the Geological Survey, made a reconnaissance survey of the property (1), and since that time work of the same nature has been done by several others. MacGregor has published some interesting data on the Amulet mine (2). Using as a background a summer's work on the Horne claims at Noranda, the writer spent the summer of 1929 at the Waite.

Jan 1, 1931

By Alan Bateman

Introduction A few years ago the name Katanga recalled, to those interested in copper, a far-off country in central Africa where deposits of huge size were beginning to pour a stream of copper into the world's markets. But no one heard of the adjacent part of northern Rhodesia as a potential copper region. It was then a bush-covered wilderness, with a few lonely, widely-spaced villages, and here and there a copper prospect that created but little outside attention. There was also one struggling mine whose development created pessimism. The low-grade carbonate outcrops of Rhodesia did not compare favourably with the rich carbonate ores of Katanga. And, since Katanga was mining only oxidized ores, it was then thought that this adjacent region likewise would contain only oxidized ores. The one mine that had been started, Bwana M'Kubwa, was working on low-grade carbonate ore at a loss. The outlook was not promising. But, a little over three years ago, the aspect changed. The vision of one far-sighted engineer embraced the possibility that here copper sulphides might underlie those low-grade carbonate croppings. His courageous associates furnished the capital; drilling commenced, and the great Roan Antelope mine rapidly emerged. In quick succession, the N'Kana, Mufulira, N'Changa, N'Changa Extension, and Chambishi mines were heard from. Prospecting and development are now proceeding apace, towns are being hewn out of the virgin bush, plants are being reared, and ramifying branch railways are being pushed out from the single line of steel that now connects Rhodesia with the coasts to the south. A great new copper-mining centre is in the making, about which the world will hear much in the future. As with most new mining camps, rumors abound regarding its ore possibilities; some are correct, some are erroneous, and reliable information unfortunately is all too scanty.

Jan 1, 1930

By J. D. R. Neilsen

The objective of the research conducted and presented herein was to determine the effect of pre-established free gas saturation on the sweep efficiency of an isolated inverted five-spot well pattern. The investigation concluded that the ultimate recovery of an isolated inverted five-spot may be slightly increased by establishing a free gas saturation prior to water flooding; however, of more significance is the extreme deviation of the pattern's performance after water break-through from that commonly obtained from developed well patterns. The rapid "water-out" characteristic common to both linear floods and floods conducted in developed well patterns was not evidenced in the isolated inverted five-spot. Instead, the wells continued to produce oil long after breakthrough until ultimate areal sweep efficiencies of four, five, and six hundred percent were obtained prior to the water-oil ratio becoming excessive.

Jan 1, 1962

By Henry C. Knight

A number of improvements in the techniques of budgetary control have been developed in the 1970's. The most significant of these is zero-base budgeting. This procedure is a marked improvement, because it overcomes some of the key weaknesses inherent in most traditional approaches to budgeting. It incorporates techniques and disciplines which improve the quality of both the budgeting effort itself and the documents that most senior managers will need to evaluate. The end result is a budget that establishes and improves cost effectiveness. This budget is based on resource allocations using cost-benefit criteria and on a system of prioritization for making funding choices. Zero-base budgeting is applied only to costs and expenses that are not conducive to control using industrial engineered standards. Therefore, the benefits attributed to zero-base budgeting will only hold true for administrative, selling, exploration, safety, fire protection and overhead, and other indirect types of costs and expenses. It is in this context that the question of its attractiveness for the mining industry is dealt with.

Jan 1, 1978

By J. E. Dutrizac, J. M. Zinck

Ferrihydrite is often the initial precipitate resulting from the rapid neutralization of Fe(III) sulphate solutions, and it seems to be a major constituent of zinc plant neutral leach residues. The most important parameters affecting ferrihydrite precipitaton are temperature, solution pH and the neutralization rate. Low temperatures and rapid neutralization rates yield poorly filterable ferrihydrite, whereas higher temperatures and slower neutralization rates produce readily filterable precipitates; in all instances, however, the precipitates are two-line ferrihydrite. Significant amounts of Zn are incorporated in the ferrihydrite precipitates, and the Zn contents increase with increasing Zn concentration, pH or temperature. Generally, the sulphate contents of the precipitates decrease as the Zn contents increase, and this may indicate that the Zn is adsorbed on the ferrihydrite. Discrete Zn phases were not detected. Neither Cd nor Tl is precipitated with ferrihydrite, although thallium jarosite co-precipitates with ferrihydrite at high Tl concentrations and elevated temperatures. Virtually all of the Sn added to the solution precipitates with the ferrihydrite, but the tin is believed to be present as intimately admixed amorphous SnO2.nH2O. Although selenite extensively precipitates with the ferrihydrite, selenate remains mostly in solution, likely because of the close similarity of the SeO4 2- ion to the SO4 2- ion which is present in high concentrations and saturates the available sites for anion adsorption.

Jan 1, 1998

By F. P. Hassani, A. Hara, M. Momayez

To be competitive on the international market, the Canadian mining industry must reduce its costs, increase its productivity and maintain a high standard of safety. There is a great need today for improved methods that would allow the detection of geological structures in advance of mining to reduce dilution and the monitoring of underground structures to increase safety. This will facilitate planning for optimum exploitation of the mine and to increase production at lower costs. This paper discusses two examples of more efficient mine planning using new technologies such as Ground Probing Radar (GPR). In Kidd Creek mine, GPR technology was used at the 2500and 2600 levels to (1) monitor the stability of the sill pillar; (2) locate the presence of disseminated sulphide pockets in the sill pillar for extracting the mineral content; (3) monitor the stope backs and wall structures to evaluate the effect of on-time filling sequences; and (4)assess rockfill quality in terms of the presence of voids and fractures within the rockfilled areas. In the New Brunswick coal mine in Minto, GPR was used along with core log data to map and construct a 3D block of a section of the bench showing the relative position of different layers overlying the coal seam.

Jan 1, 1996

By J. H. Parliament

"The 15,000-tpd Similkameen open-pit copper mine, 10 miles south of Princeton, B.C., started production during 1972. The two main ore zones are separated by the deep canyon of the Similkameen River, with the Ingerbelle or western deposit being mined first. The location, design and construction of the plant were complicated by the steep terrain and the situation of the orebodies. Mining, utilizing 10-cu.yd electric shovels and 100-ton electric-wheel trucks, is conventional. Closely integrated with the preproduction mining was the construction of a 4-mile section of main highway to bypass the Ingerbelle pit. This entailed a very large fill, placed with mine equipment. Ore is crushed to minus 9 inches, stockpiled and reclaimed for direct delivery to three 32-ft-diameter by 14• ft single-stage autogenous grinding mills, each driven by two 4000-hp motors. Because of the friable ore in the upper part of the mine, 4-inch balls are added, with higher than design throughput attained. Classification is by 91>-inch spiral classifiers and cyclones. The flotation section comprises three parallel lines of ten 400-cu.ft rougher- scavenger cells and a single line of 100-cu.ft cleaner and recleaner cells. Concentrate is transported in end dump, closed trucks to Vancouver for dockside storage prior to shipment to the smelter. Tailings are piped across the canyon on a suspension bridge and through a tunnel to an empoundment area. Water is reclaimed and returned to the concentrator, forming a closed system. Dams are raised with cycloned ands, with the downstream section compacted."

Jan 1, 1973

By S. A. Briggs

Bioremediation has been accepted as a treatment technique for groundwater contamination in subsurface soils and shows promise for contaminated fractured rock environments. Biological growth in fractured rock is expected to occur predominantly as biofilms attach to the fracture surfaces. Biofilms in rock fractures are subject to a complex system of forces and other phenomenon due to the dynamics of the bulk fluid in which they grow. In this paper, through the applications of computational fluid dynamics (CFD) to rock fractures, where the boundaries are rough and the flow is complex, a precise analysis was conducted of the interaction of a fluid flow and the rock fracture. Specifically, hydraulic parameters and velocity profiles of an actual rock fracture were calculated and compared to a fracture of equivalent aperture. From the analysis it is clear that it is important to use more complex models such as the Lattice Boltzmann Method used is this paper to describe fracture flow.

May 1, 2009

By D. Bernard

Over the last decades, the wrought aluminum casting industry has made significant progress with regards to process consistency by the introduction of new technologies in the field of liquid metal processing and casting. These technologies, combined with the application of best practices, have led to increases in productivity as well as better process performances and product quality. The competition in the addedvalue aluminum products (by opposition to P1020 production) is, however, very strong and involves players that did not hold a major role five years ago but who are now exerting a strong competitive pressure on our industry even sometimes from far abroad. There are still technical and technological challenges remaining in the different areas of aluminum casting production, amongst which metal pre-treatment, furnace operations, in-line treatment and casting hold a predominant influence. The comprehension of the contribution of each individual process step to the entire process chain is a key element and must be considered in future process optimisations. This paper presents the technological position of the casting industry and tries to highlight areas where further progress can be made.

Jan 1, 2006

By D. Sagara, V. G. Makhado

"A model based control strategy was implemented at Loulo Gold Mine in Mali, to stabilise the thickener underflow stream density. This stream acts as the feed to the leaching circuit. pH control of the leaching circuit was integrated with the model-based controller due to slow process dynamics that are not suited to PID control. The controller performance was quantified over a period of 6 months, and was compared to the performance before implementation. The model based controller reduced process variability for both thickener underflow density and pH considerably, and resulted in a reduction in flocculant and lime consumption of 9.32 and 6.55%, respectively. INTRODUCTION Reagent consumption in gold processing plants significantly contributes to the total operational costs. In a typical Carbon-in-pulp (CIP) circuit, the reagent consumption associated with leaching, adsorption, elution and regeneration contribute to approximately 15% of the total operational costs (Stange, 1999). At Loulo Gold Mine, the reagent consumption associated with leaching, adsorption, elution and regeneration contributes to 6% of the total operational costs. As such, a reduction in reagent consumption will present a significant opportunity for savings on operating expenditure. Variability in feed ore characteristics results in continuous changes in steady state operating regions, which presents process control challenges as a result of the long residence times in some of the process units associated with gold processing plants. Overdosing often occurs in the presence of process variability to ensure safe operation and to maintain recovery targets. As a means of reducing reagent consumption and accounting for significant changes in the feed to gold plants, some of the plants have resorted to improving their process control strategies around their circuits. This paper focuses on the implementation of a model predictive based controller at Loulo Gold Mine on their thickener and Carbon-in-leach (CIL) tank to: •,stabilise the thickener underflow density, and •,the CIL tank pH."

Jan 1, 2017

By Martin Irving

Adding Value to Canadian Diamonds - A Changing Diamond Industry - Diamond Mining - Diamond Manufacturing - Diamond Jewellery Markets - NWT Diamonds Changing Diamond Industry - De Beers ? privatization - Oppenheimers (45%), Anglo-American (45%), Botswana (10%) ? going retail - LVMH joint venture - New Players ? jurisdictions - Canada ? companies - BHP-Billiton - Aber Diamonds

May 1, 2002

By Redhead Robert J.

"In 1991, the Canadian Council of Ministers for the Environment (CCME) charged its Waste Management Task Group with developing a nationally coordinated strategy to measure, monitor, and achieve the objective of decreasing the generation of waste (solid and hazardous) by50% from 1988 levels by the year 2000.With the encouragement of the CCME, which viewed hazardous waste as largely an industry problem, a committee, the “Industry Action Group”, representing eleven industry trade associations with a strong interest and involvement in hazardous waste was recruited.The Municipality of Markham, Ontario was also recruited (Appendix 1)."

Jan 1, 1996

By D. W. R. Haysom

"I AM CONSCIOUS of the honour you pay me by having invited me to address you on the subject of the Rehabilitation of the Sydney Steel Corporation. The true architect of the revival and rehabilitation is Robert Burns Cameron. Because of the numerous myths which have grown up around what seems to be the miracle of the revival of the Sydney Steelworks, I propose to go back to the time when they came under the full control of the Province, on the 1st of January, 1968. Late in 1967, the decision was taken by Premier G. I. Smith to keep the Steel Plant running for at least another year, in an endeavour to see whether the enormous losses being sustained by Dosco could be reduced to a level which would permit their continuing operation. When that decision was taken, Dosco was to continue management until the 30th of April, 1968, and in the intervening period, the Provincial Government would seek management of the right calibre to ensure that an objective view of the Steelworks operations could be secured. By a combination of circumstances which can only be described as most felicitous, the man selected for the task was R. B. Cameron. He very quickly determined that to permit Dosco to continue management of the Steelworks until April 30 could only result in heavy losses to the Province and a consequent deterioration in the already critical financial position and a declining morale of the worke"

Jan 1, 1972

By Allan A. Este, Bruce Arthur

"Rio Algom's Stanleigh Mine and Mill Operation Was' officially started up in August 1983. In September 1982, Rio Algom contracted Estonix International Inc. from Lively, Ontario, to develop and implement two innovative programs: (1) Work Renovation Planning, and (2) Systems Performance Training. This paper deals with the development and implementation of these two concepts relative to the plants technology from start-up to present and the exceptional results achieved. This paper discusses how a small but motivated workforce resulted in the smooth transition from startup to full production. It also deals with how these concepts were applied elsewhere in the organization which permitted a successful transition and downsizing of the over-all operation.IntroductionRio Algom Limited produces uranium in Elliot Lake, Ontario. In the late 1970s Rio Algom entered a contract with Ontario Hydro to supply uranium from its Stanleigh property, which had been idle since 1960. The mine was subsequently upgraded, and a new modem mill was designed and built, commencing operation in 1983.From then until September 1990,Rio Algom had three producing mines and mills in the Elliot Lake area. Quirke mill, with a capacity of 6350 tonnes per day, operated continuously from 1968. The Panel mill with a 3000 tonnes per day capacity, operated since 1979. Stanleigh mill continues to operate under long-term contracts, although at a production rate about 25070 lower than its rated capacity of 5000 tonnes per day.Both the Quirke and Panel mills, although not entirely similar, were conventional uranium mills utilizing crushing, grinding, leaching and ion exchange. As such, and in keeping with the traditional management style, there was a rather large mill operating workforce, which utilized a line-of-progression job classification system."

Jan 1, 1993

By M. Gagné, F. E. Goodwin

The mining industry represents a significant investment in infrastructure of which steel plays a key role. Many structures in a mine are made of steel including shaft structures (buntons, station steelwork and headgear); stope structures (roof supports, pipe hangers); haulageway structures (ore transfer stations, electrical stubbies); and surface structures (plant buildings, tank supports, pipe gantries, conveyor belts, stacks, stockpile structures, stairways and railings). Maintenance of structural components can often be difficult because of the environment, including those where corrosive fumes persist, or limited access, such as in shafts where access is limited, or to short maintenance shifts or where limited working space is available. Thus a cost-efficient, long-lasting and maintenance-free protection system for steel should be specified. Galvanizing provides the required high-quality, long-term corrosion protection to steel. Galvanizing provides protection in two ways, first as a physical barrier to corrosion and secondly by means of cathodic or sacrificial protection that is unique to zinc. The dual nature of corrosion protection provided by galvanizing significantly extends the service life of steel even in the most challenging environments. The unique corrosion protection properties provided by galvanized steel will be highlighted with global mining application case studies.

Jan 1, 2015

By G. D. Bysouth, G. Y. Wong

"The Endako molybdenum deposit is located 160 km west of Prince George, British Columbia. It occurs within the main body of the Francois Lake Intrusions, a composite batholith consisting of early, middle and late intrusive phases. The ore deposit is confined to Endako Quartz Monzonite, a middle phase intrusion, which is bound on the north by Carey Alaskite and on the south by Francois Granite, both late stage intrusions. In the mine aretz, the Endako Quartz Monzonite has been intruded by pre-ore dikes of quartzfeldspar porphyry and porphyritic granite, and by post-ore dikesof basalt.The Endako deposit forms a west-northwest trending body that has a strike length of 3360 m and an apparent width of 370 m. It consists of four structurally distinct zones: Endako East, Endako West, Denak East and Denak West. Principal sulphide minerals of the deposit are pyrite and molybdenite, accompanied by magnetite and minor chalcopyrite. Galena, associated with wulfenite and bismuthinite, occurs in some ores of Endako West and Denak as minute inclusions in molybdenite. The sulphides and associated minerals are hosted by quartz veins which occur principally in vein systems. Hydrothermal alteration accompanying ore mineralization has pervasively kaolinized the quartz monzonite host rock, and has locally produced K-feldspar and quartz-sericite-pyrite envelopes on quartz veins.Primary structural controls of the deposit are southwesterly dipping vein systems which strike 110° in the Endako zones, 110° to 130° in Denak East and 170° in Denak West. Secondary structural controls are northeasterly striking vein systems that dip northwesterly in Endako East and southeasterly in Denak. Domal uplift accompanying the rise of latest stage magma is considered to have caused intense dilatant deformation along older west-northwest trending shear zones, producing an elongated structural host for ore deposition."

Jan 1, 1995

By G. H. Montgomery

THE PROPERTY of Aunor Gold Mines, Limited, consists of eleven claims, located in Deloro township, approximately three miles southeast of the town of Timmins. Production began in 1940 and currently the mine is operating at a rate of 485 tons per day. GEOLOGY AND MINE DEVELOPMENT The ore zone at Aunor occurs in altered lavas bounded on either side by soft talc-chlorite schist, locally known as 'soapstone'. The zone has a strike of N.80°E, dips 60° North, and varies in width from 0 to 250 feet. Within this zone the main orebody has a westerly plunge, away from the No. 1 shaft area (Figure 1). The mine is developed by a vertical three-compartment shaft from surface to the 3,082-foot horizon. Working levels are spaced at 125- foot intervals from the 625-foot to the 1,625-foot horizon, from which to tl1e 2,125-foot level the interval is 250 feet.

Jan 1, 1957

By T. E. Warren, K. W. Bowles

"IntroductionTHE PROBLEM of producing synthetic liquid fuels from coal and other raw materials is of increasing importance in Canada as well as in the United States. This is due, to a large extent, to the continually increasing demand for gasoline and other liquid products which are now obtained solely from petroleum. The United States has reached a position where domestic supplies of crude petroleum must be augmented by imports and Canada is still a long way from self-sufficiency. In the event of war, there might well be an immediate need to find supplementary sources of liquid fuels. It is, therefore, expedient to consider alternative sources of production now -well in advance of the time when supplies of petroleum may prove inadequate to meet requirements.The purpose of the present paper is to give a short review of the history of liquid fuel production from coal, to describe briefly the research sponsored by the Federal Government on the coal hydrogenation process, and finally to evaluate the present status and future trend of the synthetic fuel industry, with special reference to necessary research work.History of the Oil-From-Coal IndustryThe history -of coal liquefaction began in 1913, in Germany, with the work of Frederick Bergius. His first approach to the subject was not deliberately planned."

Jan 1, 1952