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By R. D. Merer

The production of low- and medium-Btu gas from coal provides a more economic source of energy for most industrial users than pipeline-quality coal gas (SNG), although the latter has received more publicity. The paper reviews existing and advanced methods of coal gasification, with particular emphasis on the production of low- and medium Btu gas for industrial and utility use. Some of the ways in which coal gasification can be integrated into power cycles and industrial plant energy balances are discussed.

Jan 1, 1978

By V. F. Hollister

Four conditions are commonly accepted as being needed for the development of native sulphur deposits in sedimentary rocks : (1) ample sulphate-bearing evaporite, normally anhydritic; (2) proximity to petroleum deposits; (3) a hydrodynamic system of communication between these two; (4) a stratigraphic or structural trap to prevent escape of the sulphur and sulphur -bearing reaction products. When any of these requisites are absent, apparently no significant residual bio-epigenetic sulphur deposit will form. These requirements are, however, satisfied in some areas, which include both the Triassic and Devonian evaporites of northeastern British Columbia.

Jan 1, 1977

By B. R. Hart, S. S. Dimov, J. Fournier

Carbonaceous matter (c-matter) in sulphide ores can adversely affect the process of gold recovery during cyanidation due to its ability to adsorb, or preg-rob, gold from a cyanide leach solution. This paper describes a standardized procedure for characterization of c-matter in an ore sample providing detailed information on its composition, maturity and preg-robbing capacity. The procedure utilizes the following complementary analytical techniques in conjunction with several chemical tests and assays: SEM/EDX Raman spectroscopy and TOF-SIMS. Results of the test can be used as a predictive tool to estimate the impact the c-matter will have on the gold recovery process. A comparison between predicted preg-robbing behaviour and cyanidation test results are presented.

Jan 1, 2011

By R. H. Waddington

Historical The limitations of reverberatory furnace operation have prompted many investigators to consider electric furnaces for melting electrolytically refined cathode copper. In the majority of cases where experimental work was performed, the furnace used was of the granular resistor, induction, or indirect-arc rocking type, and attempts to adapt the three-phase direct-arc furnace to copper melting appear to have been relatively few. In 1935, the International Nickel Company of Canada, Limited, carried to an advanced stage its experimental investigation of continuous melting of copper in the three-phase direct-arc furnace, and demonstrated that this process was technologically and economically practicable. Trial operations were conducted at the Huntington, W.Va. works of the Company, and were followed by the installation at Copper Cliff, Ontario, in 1936, of a full-scale unit for commercial operation. Two years later, a second unit was installed -which raised the electric melting capacity to a point permitting complete replacement of the coal-fired reverberatory furnace operation in the production of refined copper castings.

Jan 1, 1946

By Imane Benhamed, Jaouher Diouani, Laurent Cassayre, Florent Bourgeois, Carine Julcour-Lebigue, Université de Carthage

The attrition-leaching process aims at improving leaching performance when formation of passivation layers at the surface of leached particles is a severe limiting factor, as discussed recently by Julcour and coworkers (Julcour et al., 2015). This paper proposes a geochemistry-based modelling scheme for deriving the window of possible operating conditions for the attrition-leaching process to match the properties of the processed ore. The rationale is that the attrition-leaching process maintains the surface of reacting particles in an unpassivated state by continuous mechanical removal of surface leach layers, so that the process reactions can be modelled from thermodynamic equilibria throughout the duration of the process. The strength of the proposed modelling approach is that it bridges the gap between the properties of the ore and the process operating conditions. The present paper exemplifies the proposed process modelling route for derivation of the attrition-leaching process operating conditions in the context of the leaching of silicate ores, matching model predictions against controlled laboratory experiments. It is shown how thermodynamic modelling, when used in conjunction with a solid knowledge of the phases present in the system, can assist with deciding upon suitable process operating conditions. As an example, this firstprinciple modelling approach predicted that steel grinding medium would be converted into siderite (FeCO3) under a wide range of operating conditions, which led to questioning this initial choice of grinding medium for the attrition-leaching process under mineral carbonation conditions. It is emphasised that the same approach could be applied to ores of greater economic significance.

Jan 1, 2016

By Yoshimasa Funakawa, Kazuhiro Seto, Akio Kobayashi

A new hot rolled high strength steel consisting of ferrite matrix and nanometer¬sized precipitates was developed. The ultra fine precipitates were identified as TiMoC2, and the strengthening by the precipitates was evaluated more than 300MPa in case of TS/800MPa grade steel. Due to the strengthening effect of the ultra fine precipitates, alloy elements for solid solution hardening can be reduced. It is notable that the steel shows very high yield strength (730MPa in case of TS/800MPa) and very high local elongation leading to excellent stretch flange formability at the same time. The mechanical properties of the steel are attractive for chassis parts and structural parts of auto body. The steel has been produced commercially, and applied to the parts successfully.

Jan 1, 2004

By Lucien Piché

"IN any opportunity such as I am now given, I suppose that one should not fail to say that what the world has to offer to this year's graduates in science and in engineering is the greatest promise ever held out. High-ranking new scientists and engineers -particularly those with the Ph.D. degree -find themselves in an apparently delightful situation; the glow of attention that surrounds them and the dazzling starting salaries that are offered to them may indeed be turning their heads a bit and the attitudes of some of them are sometimes expressed with a smugness that can find its equivalent only in freshmen. On the average, however, the new graduates are, without any doubt, the best trained ever, or at least they have been the most expensive to train in the universities.There appear to be exciting opportunities for competent, well-trained and educated scientists and engineers far beyond the numbers that can be annually produced, and the demands for excellence in depth as well as in breadth of training probably will continue to increase for many years to come. The problem is visible all around us in Canada that there is much more money to buy brains than there are brains to be bought."

Jan 1, 1966

By Ben C. McLellan, Philip J. Bangerter, Andrew Murphy, Glen D. Corder, Damien Giurco

Sustainability now forms a critical part of metallurgical plant design. In addition to compliance with requirements and corporate principles, design engineers must also consider how community and societal responses to the metallurgical industry affect the way they design and build plants. Three broad areas to consider are: the design engineer’s contribution to sustainability through the design process and the relationship to the social license to operate (SLO)—the unwritten license communities give companies to safely and responsibly operate the plant and equitably share benefits; the realization of sustainability goals through methodologies emerging in the design activities; and the integration of design frameworks into a contemporary project design context and its investment objectives. This chapter explores sustainability in metallurgical plant design in the context of SLO, design tools and frameworks, and community and societal influences.

Jan 1, 2015

By Thomas Kilpatrick

The liability created by building this railway is the great financial problem before the people of British Columbia at the present time. In dealing with the subject, I propose to divide it into three periods: The Past - The Present - and The Future. The Past The primary objects in building the railway were to provide an independent and direct route for the Grand Trunk Pacific railway into the city of Vancouver, and to open the central and north-eastern portion of the province.. This vast territory, almost one-half the entire area of British Columbia, has great wealth in fruit, agricultural, and grazing lands; timber, coal, water-power and minerals of all kinds, including some of the richest placer deposits in the world. Rivers and lakes teem with fish. Big game, including moose, elk, caribou, deer, grizzly and black bear, mountain goat and sheep, is plentiful and there is an abundance of small game and fur-bearing animals. In addition, its scenic attractions are unsurpassed in Canada. To develop these resources it was considered necessary to build a railway from south to north as a main artery of transportation and, if necessary, branch lines to carry heavy .shipments of coal or other commodities. Lighter freight may be handled by motor trucks from distant points to the railway.

Jan 1, 1925

By R. ZapataN.

"In the following report, Altonorte Smelter owned by Xstrata will explain its experience with its denominated furnace called ""Continuous Altonorte Reactor"" since started up in March 2002. The Reactor is the main and only smelting furnace since the operation of Reverb Furnace was stopped (15 days after the start up of the Reactor) and it can be operate with dry concentrate for injection by tuyere and wet concentrated via Garr Gun when the injection system fails. From the started up of the Reactor, three operational campaigns have been carried out where in each one they have been increased their smelting throughput and availability. The flexibility reached by the technology bath smelting has allowed a high level of smelting of concentrate and revert materials. The high availability of the Reactor and overcoming problems that were considered of high complexity like the extraction of white metal and slag, refractory campaign, etc. has allowed the Altonorte smelter to project to smelting 1,200,000 tonnes per year with its only Reactor in next year."

Jan 1, 2007

By D. Marcotte

The Rock Quality Designation (RQD) is a standard scalar measure of rock quality used in common rock mass classification systems (e.g. RMR, Q system). RQD is measured along diamond drill holes. RQD interpolation between holes is nontrivial. Despite the inherent limitations of drill hole data and the local complexities of structural geology, it is often the only information available for mining and major civil engineering projects. Therefore, maximizing the usefulness of this data is warranted. We derive a correction for directional effects that help reduce the bias and improve the accuracy of the estimations. The correction is derived with the aid of numerous simulations. It relies on simple information, the angle between the joint normals and the borehole axis (JO). A reference direction is identified as the borehole direction with smallest JO. A multiple linear regression model based on JO statistics in the various boreholes defines the correction model. The corrected RQD values are then interpolated. It is shown the method enables reducing the bias on RQD estimation by 50% and improves the accuracy of the estimates by 30%. The corrected RQD values show stronger spatial continuity than the raw values. The benefits of estimating the RQD indirectly by using joint frequency measures are also assessed.

May 1, 2003

By Staff

The Tetreault mine, operated by the British Metal Corporation (Canada), Limited, holds a unique position in Canadian mining, being the only steady producer of zinc in Canada east of the Rocky mountains. Its importance in Canadian zinc production may be gauged with some accuracy, since, in 1927, it was responsible for over 13 per cent of the zinc output of the Dominion. In addition, it also made valuable contributions to the production of lead, silver, and gold. Location: Situated in the foothills of the Laurentian mountains, 600 feet above sea level, 20 miles from the St. Lawrence river, and 52 miles due west from the city of Quebec, the property is in the township of Montauban, county Portneuf, Province of Quebec, as shown in Figure I. The municipality of Montauban, immediately adjoining the mine, has a permanent population of 700 people and is six miles by road from Notre Dame station on the main line of the C.N. Rys. between Montreal and Chicoutimi-Notre Dame being n6 miles by rail from Montreal. Connection by 19 miles of dirt-and-gravel road with the Provincial highways' system of Quebec Province, the city of Quebec, which is distant 78 miles, can be reached by automobile in less than three hours, while the distance to Montreal by road is 16o miles .

Jan 1, 1928

By L. Yuan, J. H. Rowland, R. A. Thomas, D. Bahrami, G. P. Cole

"The past several decades have seen a steady increase in the use of atmospheric monitoring systems (AMS) in underground mines as sensor technology has advanced and costs for this technology have decreased. The AMS is a reliable tool for early mine fire warning by detecting gaseous products of combustion in underground mines. During a mine fire emergency, mine decision makers rely heavily on the prompt and accurate knowledge of the ventilation and fire situation in the mine, such as fire location, fire size, and the spread of smoke to make effective and efficient decisions on firefighting strategies and miner evacuation. Meanwhile, a prediction of the potential for fire development at a later time, such as whether the currently designated mine escapeways will be contaminated by smoke and toxic gases with the progress of the fire, is critical for effective decision-making to save lives that are in danger. The AMS monitoring data, including carbon monoxide (CO) concentration, airflow rate, smoke, etc., can provide information as to whether the smoke has reached the locations where AMS sensors are installed and if a mine-wide smoke spread has occurred. The National Institute for Occupational Safety and Health (NIOSH) has undertaken a task to integrate real-time AMS monitoring data with the mine fire simulation program, MFIRE, to simulate and predict the spread of smoke and toxic gas in a ventilation network based on the real-time AMS data. This paper reports the developed real-time method for characterizing the size and location of an underground mine fire and for predicting the spread of contaminants throughout the mine ventilation network using sensor data from the AMS.INTRODUCTIONNIOSH conducts research to develop workplace solutions to improve detection of and reduce the risk of hazardous conditions in underground mines. The advancement of senor technology and the increasing demand for real-time mine parameters monitoring have led to extended applications of atmospheric monitoring systems (AMS) in underground mines worldwide. In the United States, AMS is primarily used for early mine fire warning by detecting carbon monoxide (CO) in fire hazard areas, such as belt entries. Mine fires can grow rapidly, and time is the critical element. Prompt detection, timely and accurate warnings to those miners potentially affected, and a proficient response by underground miners can have a tremendous impact on the social and economic consequence of a small underground mine fire (Conti et al., 2005). The early detection of a mine fire could gain time for the first responders to put out the fire before it develops into a disaster. An AMS system with CO sensors has especially played an important role in the early detection of mine fires. The continuous monitoring of an underground mine atmosphere with an AMS could generate a large amount of data in a mine fire event. However, the current application of AMS is mainly limited to sending out an alarm when monitored CO concentration exceeds a certain level. An opportunity arises as to whether these data can be further used in fire emergency response. In order to make effective decisions on firefighting strategies, mine workers’ seeking refuges, evacuation and escape, and the timing on when to send rescuers, decision makers need accurate and timely knowledge of the ventilation and fire situation in the mine. Information about the fire intensity, where in the mine the smoke and toxic gases have spread, and whether designated mine escapeways have been compromised by smoke and toxic gases from the fire would greatly increase the effectiveness of these decisions. However, the monitored AMS data only provides atmospheric conditions in the vicinity of sensor locations. What is concluded from the monitored AMS data highly depends on the decision makers’ capability and experience. Predictive insight into fire growth and smoke transport would greatly help decision makers during a fire emergency."

Jan 1, 2019

By Jörgen Appelgren

Atlas Copco, a leading supplier of equipment and services to the mining and construction industries, is consistently pursuing its strategy to offer the most productive and economical solutions by continuously offering new innovative products. These are in most cases developed and tested in close cooperation with demanding end users before being officially launched on the international market. The demands for higher productivity and improved overall economy have resulted in systems for automation of the drilling cycle and also tools for integrating the Drilling equipment to the production control system used by the customer. In terms of improving the blasted material quality, Atlas Copco has placed emphasis on hole straightness and the need for hole logging and positioning. By applying state of the art technology to today?s computerized drilling rigs, major steps in improving overall drilling and blasting performance have been achieved. This paper will give some examples derived from the latest development of solutions for the Rotary drilling product line.

Oct 1, 2009

The Nak?azdli First Nation and the municipality of Fort St. James are located in the Stuart Lake/Nak?al Bun area and are not unfamiliar to mining. These northern British Columbian communities have been associated with the historic Pinchi Lake Mercury mine and today are closely linked with British Columbia?s newest mine, the Mt. Milligan mine. Prior to the construction of Mt. Milligan, community health and social service providers were concerned about potential impacts that would occur from new mineral development activities. This concern has led to a partnership between the above communities and researchers with expertise in the area of mining and health. This paper describes: the current mining and health environment with a focus on British Columbia; mining trends in the Stuart Lake/Nak?al Bun area; the current community-based health research project funded by the Vancouver Foundation and the Canadian Institutes of Health Research, and; a suite of community-based health recommendations to mining companies on key issues to consider when developing projects near municipalities and Aboriginal communities in Canada, based upon one of the newest mines under development in Canada.

Aug 1, 2013

By J. M. Carr

The history, geological setting and local geology of the Magnum vein system, 100 miles west of Fort Nelson in northeastern British Columbia, are described. The system comprises a number of quartz-ankerite veins, mineralized with chalcopyrite and lesser pyrite, occurring in a steep northeastly zone of deformation and subsequent dike intrusion within otherwise little-deformed Precambrian sedimentary rocks. In April of 1970, Churchill Copper Corporation began producing copper concentrates in a 750-tpd mill fed from the Magnum mine.

Jan 1, 1971

By H. L. Cheng, C. H. B. Leitch, C. T. Hood, A. J. Sinclair

"Epithermal Zn-Pb-Cu-Ag-Au quartz-carbonate-barite veins at the Silver Queen mine near Owen Lake, west-central British Columbia, are hosted by Late Cretaceous Tip Top Hill andesitic volcanic rocks. The veins form a rectilinear northwest-northeast pattern that differs slightly from regional structural trends. The main northwest-trending veins are oriented very close to the trend of regional northwest faults, but the crossing veins tend to be more east-north-easterly (070 degrees)compared to a regional north-easterly trend (040 degrees). The character of the veins suggests they are extensional features formed by dextral slip related to Paleogene oblique subduction, or intrusion of magma at depth, or both.In detailed exploration at the mine, the veins cannot be modelled as simple tabular sheet-like bodies. Instead, they are complex structures that divide and rejoin, forming multiple veins or stringers, or are found in shear zones as replacement features with quartzsericite- clay-carbonate-pyrite alteration haloes of variable width that make definition of vein margins and correlation from hole to hole ambiguous. In addition, individual veins within each of the main structures have en echelon characterboth along strike and down dip.Geological and assay data must be carefully studied to define the margins of these complex veins before any estimation of ore reserves may be made. Where multiple veins occur in a section, ore/gangue mineralogy, assays, character of wallrock alteration, and thickness of vein and mineralized hangingwall, median and footwall zones must be used to evaluate continuity of mineralized structures. Well-defined sections are projected into areas of increasing complexity. Once the vein boundaries are defined, metal concentrations, important metal ratios(Au/Ag, Pb/Zn, Cu/Zn), and true thicknesses of the vein provide the basic data for reliable ore reserve estimation."

Jan 1, 1991

By Brian W. Mackenkzie, Jozef Lajzerowicz

This paper is intended to familiarize planners in the noncommunist world with the district planning approach used in eastern Europe for mining development. It deals generally with the basic nature of the district planning problem, the planning process for mining development and the state organization for the planning of mining districts. A number of applications of district planning techniques to both established and new eastern European mining districts are described.

Jan 1, 1971

By S. S. Yuan, Q. Z. Zhu, J. F. Shao

"This paper aims at enriching a homogenization-based anisotropic damage model for hard rocks under complex loading. A new damage criterion is proposed to capture material strain softening. Within the framework of irreversible thermodynamics, we are particularly concerned with two strongly coupled dissipative mechanisms: frictional sliding and damage by microcracking, which usually take place at cracks within cohesive geomaterials under compression. Focusing on the representative elementary volume containing multiple crack families, the free enthalpy of the matrix-cracks system is obtained. Importantly, a back-stress term is involved in the local stress applied to microcracks. This back stress plays the hardening/softening role in the friction criterion which is formulated at local scale. Strain hardening owns to the accumulation of frictional shearing and dilatancy while strain softening is caused by crack growth. The multiscale damage model is used to simulate laboratory tests on the Westerly granite under true triaxial compressions. INTRODUCTIONWhen subjected to compressive loads, hard rocks present nonlinear mechanical behaviors and induced material anisotropies. In that process, two main dissipative mechanisms have been largely identified: damage by crack growth and frictional sliding along closed crack faces, which are usually strongly coupled to each other on crack scale. Theoretical investigations have shown that the damagefriction coupling analyses allow explaining a large number of experimental phenomena involved in brittle or quasi-brittle materials. Concerning constitutive modeling, the standard Eshelby’s solution-based homogenization procedure for heterogeneous materials was recently applied successfully to describing the mechanical and poromechanical behaviors of cracked frictional solids."

Jan 1, 2015

By Gary M. Poxleitner

Skip/Hoist ?Vertical Advantage of Hoist ?High capital ?High operating cost Trucks Trucks ?Flexibility of ramp ?Low capital ?High operating cost Conveyor Inclined High capital ?Low Cost to run ?Continuous Production ?High Capacity ?Transfer pointsMax Grade: +32%

Feb 1, 2008