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By I. I. Inculet, M. A. Bergougnou, J. D. Brown, R. M. Quigley, D. K. Faurschou

"Coal from Hat Creek, B. C., has been successfully beneficiated to remove ash while retaining calorific value by a dry electrostatic separation process using a fluidized bed for triboelectrification. Two samples of Hat Creek coal used in the beneficiation experiments have been characterized particularly with respect to their mineral and clay content. The calorific value recovery exceeds the simple dry coal recovery because of the heat lost in altering the clay minerals of the ash fraction during burning. Recoveries and ash contents of the beneficiated coal are comparable to recoveries by water washing, but the dry process avoids the potential water pollution problems.IntroductionProposals have been made which suggest an interim Canadian coal production target for the end of the century which will require a four- to fivefold increase over the 1977 production. This implies a nominal annual growth rate of about 6070 to achieve a production rate of 115 to 140 million tonnes/year. Whether or not this target is realistic, it is becoming increasingly evident that coal must be utilized more fully on a world-wide basis. The crisis in Iran has provided the latest stimulus to renewed interest in Canadian coals for domestic use and export.The emerging new era of coal utilization for fuel and chemical feedstock will not, however, generally tolerate the level of coal technology which prevailed prior to the availability of abundant cheap oil and natural gas. Economic, environmental and resource management considerations will necessitate, for example, the use of improved methods of beneficiating coal. Continued development and application of conventional processes, principally aqueous, involving heavy media and cyclones will solve many of the problems. However, less conventional processes may be preferable or necessary in certain applications."

Jan 1, 1980

By Ginger Gibson

As an occupational culture, mining comes with its own set of rules, agendas and values. Yet mines often also operate in the traditional territories of indigenous communities, with whom specific agreements are negotiated that commit to respect culture, economy and environment. Mines in these locations employ extremely diverse workforces whose value systems often come into conflict in on-the-job relationships. Adaptation of individual worker attitudes and industrial operating culture thus both need to occur if there is to be the negotiation of a workable relationship. This paper will discuss ways that NWT diamond mines have adapted to their workforce, to ensure that rights and cultures of their diverse workforce can be respected. Historically, the concept of culture has been dealt with solely through the forum of ?cross-cultural? workshops. Gibson presents a model of a new type of ?cultural-engagement? workshop based on the top ten cross-cultural conflicts that actually arise at a remote mine-site. This model helps managers, team leaders, and workers to tackle in-mine conflicts that arise based on differing value systems of aboriginal and non-aboriginal workers and management. In addition, Gibson suggests that the concept of culture must be more rigorously applied throughout the mine structure and not discussed only in the forum of the cross-cultural workshop.

May 1, 2007

By John Campbell, William Trahant

"Total Quality Management (TQM) is becoming a reality in the mining industry. Widely adopted in the manufacturing and services industries, TQM has become the operating style of choice in numerous mining companies across the Americas and Australia. Iron Ore Company of Canada, Inco, MSA, Graniterock, Magma Copper, and CRA's Hamersly Iron - all are pioneers of TQM. These companies and others are confronting the challenges of implementing TQM and are managing the changes required of their people and cultures. What these companies are doing, why they are doing it, and how they are successfully managing the changes are the subjects of this paper.Driving the need for change in these organizations are a host of issues, some of which all mining companies are facing. Requirements from customers for ISO 9000 certification is becoming one of the initial motivators for Total Quality Management. These standards, commonly used in manufacturing throughout the European Community (EC), emphasize quality in the processes that create outputs, instead of just the outputs themselves. Iron Ore Company of Canada, for instance, responding to the requirement of one of its customers, British Steel, has become one of the first mining companies to meet the quality standard. Suppliers who meet the standards are highly desirable to customers who are themselves operating under the ISO or their national quality guidelines."

Jan 1, 1995

By N. R. Thote, J. L. Porathur, C. P. Verma

Highwall mining is a highly mechanized coal mining method associated with several advantages, such as a very high production rate (approximately 3,000 t/d) and low production costs. There is no requirement for underground support, ventilation, or blasting. Production leads to added recovery, which is otherwise lost in the ultimate pit. The use of highwall mining can bridge the gap that exists between supply and demand in the energy sector. This paper presents a brief review of highwall mining technology, including current status, analysis tools, and design techniques. In addition, it identifies important parameters from the analysis of failure case studies.

Jan 1, 2014

By Y. Yhang, D. C. Sego

ABSTRACT This paper evaluates the potential of freeze-thaw dewatering using Albian mature fine tailings (MFT). Freezing tests were first performed to study the effect of freezing rate on dewatering efficiency. Lower freezing rate resulted in higher thawed solids content and shear strength. Subsequently, large strain consolidation tests were conducted to investigate consolidation behaviour and how it is affected by freeze-thaw. The consolidation behaviour was presented in terms of effective stress versus void ratio and permeability versus void ratio. The results can be used to predict the field behaviour of Albian MFT and optimize the application of freeze-thaw for MFT dewatering.

Jan 1, 2014

By H D. Smith

T HE production of coal in Canada was slightly higher in 1964 than in the immediate past, and the major users continue to be the electric utility and metallurgical industries. There are continuing trends toward the increased use of cokes and chars in various metallurgical applications. Geological Research During 1964, the coal drilling program of the Research Council of Alberta (RCA) was concentrated in the extreme south of the Province (notably in the Milk River area and the region immediately to the northeast of this area). Field work commenced on June 1 and was completed at the end of September, by which time a total of 376 holes, aggregating some 48,500 ft., were drilled in 132 townships. Although no new major coal occurrences were intersected, the pro-gram yielded useful data for defining the extent of the known coal deposits in the area. Detailed results will be analyzed during the winter and reported in due course. Meanwhile, a full report on the

Jan 1, 1965

By B. K. Mishra, Subrat Kumar Padhy, B. C. Tripathy, I. N. Bhattacharya

Manganese is a difficult metal to electrodeposit due to its high electronegativity and continues to possess unique process challenges. Manganese deposits of high quality are electrodeposited on 316 grade stainless steel from sulphate solutions in the presence of organic additives such as tetra ethyl ammonium bromide (TEABr), tetra propyl ammonium bromide (TPABr), and tetra butyl ammonium bromide (TBABr). The concentrations of these additives were examined over a relatively broad range to evaluate their effect on current efficiency, specific energy consumption and deposit morphology of the electrodeposited manganese metal. A maximum current efficiency of 68% was achieved in the presence of TEABr in the bath. X- ray diffraction studies revealed that (330) (411) planes were the most preferred planes of crystal growth during manganese electrowinning at a current density of 500 A/m2 resembling alpha-manganese irrespective of the nature of additive. Scanning electron micrographs showed smooth and uniform deposit morphologies when manganese was electrodeposited in the presence of TEABr.

Jan 1, 2014

By F. R. Archibald

MR. A. F. B. Norwood: Having been associated in the past few years with nine different plants roasting aurif erous concentrates in Australia, two of which were new installations for which design and construction were undertaken by the writer, I read Mr. Archibald's paper with very great interest, and I deem it a great privilege, as a member of a sister Institution, to be invited to contribute to the discussion on the paper. I wish to congratulate the author on a very informative and interesting paper, and, although situated many thousands of miles away, I feel I have gathered from it a very close idea of the operating conditions and of the work that has been carried on at the Beattie gold mine. Working along somewhat different lines, it is interesting to note that the conclusions drawn by the author run closely parallel to those accepted in Western Australia, viz., that the object of roasting is to obtain a porous calcine, and that this can best be achieved by roasting first at a temperature below 900 deg. F. to 1,000 deg. F., and then raising the temperature at the finish of the roast. Turning first to the laboratory work, the materials I have studied in Western Australia cover a range from those with little or no arsenic to concentrates carrying as high ?as 20 per cent, i.e., even higher than in the analysis quoted for the eoncentrates from Nepheline Products, Limited. In the ease of arsenic-free pyrite concentrates, the roast is ideally carried out at a temperature ranging from 900 deg. F. to 1,000 ferric oxide is one cause of the refractory gold remaining In deg. F. No improvement in extraction is obtained when the calcines are cyanided by raising the final temperature above this point; nevertheless, in technical practice it is desirable to finish the roast at 1,200 deg. F. in order to decompose basic ferric sulphate and thereby reduce the consumption of chemicals in the subsequent cyanidation step. However, if at any stage of the roast the temperature is raised above 1,200 deg. F., the extraction by cyanidation falls, and continues to do so the higher the maximum temperature that is reached. Line A in the accompanying graph typifies this effect.

Jan 1, 1949

By Marvin J. Udy

THE preparation of this paper is in response to many requests for in-formation on the mining and smelting developments which have been carried on for the past three years or more by the Chromium Mining and Smelting Corporation of Canada. By way of introduction, the following paragraphs, relating to the early history and present status of the chrome-mining industry in the United States, are of interest. They are quoted from Bulletin No. 76 of the California State Mining Bureau, published in August, 1918: 'Chromium was discovered about 1797 by a French chemist, Louis Nicolaus Vauquelin, in ore from Siberia. From that time until 1827, the Urals, in the region of Ekaterinburg, supplied the chromium used in . Europe. In the summer of 1827, as the historian advises us, Isaac Tyson, Jr., saw in a Baltimore market-place a cart containing a cider barrel, which was held from rolling about by some heavy black stones. He had made a study of such stones at the first-known American locality, the Bare hills near his father's home, six miles from Baltimore, and he recognized the black stones as chromite. On inquiry, he found the chromite came from the Reed farm in Harford county, 27 miles northeast of Baltimore. At this time, Tyson was one of the very few men in the country who knew the value of chromite, and in the next few years he took full advantage of this knowledge. He immediately bought the Reed farm. He found about 30 tons of float-ore on the surface, but there was no outcrop of ore in place. Never-theless, he sank a shaft, and at a depth of eight feet struck an ore-pocket which proved to be 80 ft. long, 25 ft. wide, and 8 ft. in maximum thickness. His next discovery was of placer chromite in the sands in the beds of brooks on an estate called Soldiers' Delight, 16 miles northwest of Baltimore. Thus far, Tyson's observations had shown him that chromite occurred apparently only in serpentine areas. His explorations were now leading him farther afield. In 1828, he found on the Wood Farm, in Lancaster county, Pennsylvania, a deposit of float chromite which led him to lease the ore-right of the farm, which he finally purChased in 1832. Here he developed the famous Wood mine, the largest single producer of chromite in the world.

Jan 1, 1938

By Jean-Louis Robert

Field work inaugurated in 1962 in the townships of Lemieux and Lesseps, in the Gaspe Peninsula of Quebec, has permitted the author to delineate the lithologic units of the area, to elucidate a few stratigraphic problems and to outline several zones of alteration. Certain features of these zones and the numerous mineralized showings in the area merit the attention of prospectors and exploration companies.

Jan 1, 1966

By H. A. Halupka, I. A. Mozer

"At its plant in San Juan, Peru, Marcona Mining Company operates two grate pelletizing furnaces for the agglomeration of 3.5 million long tons of magnetic concentrates annually. Line One, installed in 1963, was built by Lurgi as a downdraft process furnace utilizing a furnace fan for the recuperation of hot gases from the cooling zone. This line was modified in 1966 to include both updraft drying and downdraft drying, and the original roof burners were converted to side-wall burners. Line Two, a Dravo-Lurgi furnace with an annual capacity of 2.4 million long tons, was built in 1966. This line, in contrast to the modified Lurgi furnace, employs direct recuperation of hot gases from the cooling zone and utilization of process gases from the firing zone for updraft drying.At its plant in San Juan, Peru, Marcona Mining Compa-ny operates two grate pelletizing furnaces for the agglo-meration of 3.5 million long tons of magnetic concentrates annually. Line One, installed in 1963, was built by Lurgi as a downdraft process furnace utilizing a furnace fan for the recuperation of hot gases from the cooling zone. This line was modified in 1966 to include both updraft drying and downdraft drying, and the original roof burners were converted to side-wall burners. Line Two, a Dravo-Lurgi furnace with an annual capacity of 2.4 million long tons, was built in 1966. This line, in contrast to the modified Lurgi furnace, employs direct recuperation of hot gases from the cooling zone and utilization of process gases from the firing zone for updraft drying. 5 per cent increased capacity, 30 per cent lower fuel oil consumption, and approximately 400 per cent reduction in grate bar and pallet corrosion. Firing of the pellet bed was improved by conversion from roof to side-wall burners. This modification also permitted utilization of monolithic refractory in place of pre-fired shapes, thereby improving over-all furnace availability and reducing refractory stock requirements from 154 different shapes to 18.Data are presented to compare operating performance of the Dravo-Lurgi furnace and the modified Lurgi furnace. These data show 30 per cent lower fuel oil consumption and 10 per cent higher capacity per unit grate area for the Dravo-Lurgi furnace, which also averages higher availability due to greater operating flexibility."

Jan 1, 1970

When underground extractions occur beneath or in close proximity to valleys and other forms of irregular surface topographic features, the observed vertical subsidence at the base of the valley is less than that would be expected in flat terrain, while the valley sides are observed to move inwards towards the centre of the valley. The reduction in subsidence at the bottom of the valley is referred to as upsidence and the convergence of two sides of the valley is termed valley closure. Research coupled with mining experience over the past few decades in Australia has identified valley closure subsidence as being very real and quite significant part of non-conventional subsidence effects, which always have adverse effects on natural features, with risks to water flow and aquatic ecosystems. In this paper, we describe a threedimensional numerical modelling approach to investigate the geomechanical mechanisms which cause the valley closure subsidence behaviour, using distinct element computer package 3DEC. The calibrated models can accurately predict subsidence and horizontal displacements, and they are subsequently extended to specifically study the effect of a series of mining geological and topographical factors on valley closure subsidence phenomenon, by developing a range of hypothetical scenarios. Previous analyses carried out using a two-dimensional numerical modelling technique have identified the potential parameters that affect the valley closure subsidence, which mainly include longwall position, horizontal stresses, valley sloping angle, and valley shape. Further three-dimensional analyses regarding the relationships between the major factors and valley closure subsidence are discussed in this paper. The results have significant implications with regard to both the underlying mechanisms that lead to this nonconventional subsidence behaviour, and how these should be incorporated in future valley closure subsidence prediction and mitigation of its impacts on natural features.

Jan 1, 2015

By F. K. McKean

THE task of establishing a new corrosion testing laboratory is more difficult than it need be because there is very little information on the subject available in the literature. Many articles describing tests and results may be found, but a wide search will unearth only passing remarks on the different types of equipment that may be selected for accelerated corrosion tests. An article describing some of the apparatus needed in a corrosion laboratory should be of help to those interested in building a new unit or in making additions to an old one. In May of this year, the writer was given the assignment of equipping a laboratory for general corrosion testing, to form a part of the new Physical Metallurgy Research Laboratories of the Department of Mines and Resource~ at Ottawa. With the help of senior members of the staff, along with what could be gathered from other sources, a list of necessary equipment was compiled and a plan for arranging it in the rooms was decided upon. Where possible, the apparatus was constructed in the excellent machine shops at the disposal of this Department, while the rest was placed on order with the manufacturers.

Jan 1, 1945

By L. R. Plitt

A series of experiments were carried out in an effort to develop a universally applicable mathematical model of the hydrocyclone classifier. The design and operating variables studied were: cyclone diameter and height, the inlet, vortex finder and apex diameters, the feed pressure and the solids content of the feed slurry. The model consists of four basic equations which express the cut size ( dso), volumetric split between overflow and underflow, volumetric throughput, and sharpness of separation in terms of the operating and design variables. Although empirical, the model is nevertheless in general agreement with fundamentally derived models. The model clearly 1•eveals the effect of the major variables on the operation of a hydrocyclone. Because of its broad data base and the inclusion of all the major variables, the model may be used without experimental data to predict the operation of cyclones over a wide range of different operating conditions. With operating data, the equations may be modified to serve as an operational model.

Jan 1, 1976

By R. E. Eyre, L. P. Landucci

C URRENT practice in the zinc concentrate roasting plant of The Consolidated Mining arid Smelting Company of Canada Limited, at Trail, B.C., involves passing the furnace effluent gases through an electrostatic precipitator for the recovery of dust. After removal of the dust the gas is treated for recovery of sulphur dioxide by conversion into sulphuric acid ( 1). However. as roasting techniques improved, and furnace productivity in-creased, the rated capacity of the precipitator was exceeded and it was necessary to consider various means of improving the dust recovery. A study of methods indicated that a baghouse using silicone-treated glass fabric, might be suitable for this particular application. Glass fabric was chosen because the temperature of the roaster effluent gases would range from 450°F to 500°F and tempering air was undesirable to avoid dilution of the sulphur dioxide gas.

Jan 1, 1962

By E. Busse

"Heath Steele Mines Ltd. operates a lead-zinc-copper mining and milling complex in New Brunswick.• During the past seven years, as ore reserves increased, the mill capacity was first expanded to 1,600 tpd and then to 3,000 tpd. In the last expansion, instead of building a completely new 3,000-tpd mill, or adding to existing installations, Heath Steele retained service facilities, buildings, ore bins, Jab, etc., and removed and replaced almost all existing process facilities. Requiring a complete mill shutdown, the expansion had to be carried out in minimum time. Also, new equipment had to fit into existing space. Critical path networks of the project were prepared, a tight schedule for construction was mapped out and progress charted daily to detect problems before they could interrupt the schedule. Heath Steele supervised the purchasing, handling and storage of new equipment, maintained liaison with the engineering contractor and became a sub-contractor, using its own staff to install all flotation equipment and process piping. The 1,600-tpd installation was dismantled and a 3,000- tpd unit was successfully put onstream in 5 months - on time and within budget. One benefit stemming from the expansion: production increased 87 per cent while operating and maintenance labour rose only 8 per cent."

Jan 1, 1972

By J. Paraszczak

High productivity of the equipment employed is one of the key factors in reducing production cost in mining. One of the best ways to achieve it is an increase in availability. In order to identify the most adverse factors affecting it, reliability and maintainability analysis ought to be done. If its results are to be conclusive, a sufficient amount of credible and consistent data is indispensable. Following the experience from field studies done in underground mines, this paper discusses the current status of failure and maintenance reporting, as well as problems encountered. It exposes the importance of adequate data collection on failures and downtime as well as it reviews the benefits of analysis based on such material. The question of benchmarking with regards to mining equipment performance is also addressed. The paper concludes with some recommendations on data collection and processing, as well as stresses the need to standardize the most important reliability/ maintenance notions throughout the mining industry and to conceive appropriate performance measures.

Jan 1, 2000

By S. Mohammadnejad, M. Olizadeh, B. Mehrabi

A new method using a combination of comprehensive mineralogical and analytical approach which includes optical and electrical microscopy and several analytical techniques with diagnostic leaching has been used to characterize the associations and distribution of gold in a variety of minerals from the Zarshuran refractory gold ore, NW Iran. Zarshuran ore with an average of 7.9 g/t Au-grade and about 8% arsenic with gold recovery less than 20% in direct cyanidation is considered as high arsenic, high au-grade refractory gold ore. In most of the refractory ores, gold is associated with arsenopyrite and co-para genetic ore minerals, while in Zarshuran ore; gold is associated with orpiment, realgar and arsenian-pyrite. Considering its mineralogy and As content, it can be considered as the most difficult refractory ore for characterization and processing. Results from the mineralogical examination and diagnostic leaches indicate that there is only a small amount of free gold (17-19%) that is present in cyanide-soluble sulfo-arsenides compounds, predominantly orpiment and realgar. Diagnostic leaches also indicate that little gold is occluded within the silicate structure (14%). Overall, the gold is mostly included in sulfides, arsenic sulfides and sulfo-arsenides (50%). The results also have shown how the technique can be used to gain a good initial understanding of potential metallurgical problems for a refractory gold ore.

Jan 1, 2005

By C. Stamberg, W. McGuire, R. C. Carlson, L. W. Vollmer

"The selection of materials and pre-cautionary measures for handling natural gas and condensate containing aqueous hydrogen sulphide are presented. Based on the results of a pilot production test and laboratory studies, together with several years . of operating experience, it was found that the behaviour of materials in sour gas environments can be predicted sufficiently accurately for engineering purposes.The selection of proper materials is essential for preventing sulphide-stress cracking. Where high strength materials are not required, low car-bon steel is used. Components requiring high tensile strength and hardness characteristics should be made from K-monel or properly heat-treated carbon-manganese-molybden-um and AISI 4140 steels. Welded connections are a potential source of sulphide-stress cracking. Consequently high quality welding and strict inspection are suggested as the most economical precautionary measures available.A maintenance program based,. where possible, on visual inspection of equipment and/or test spools located at strategic points should be used to follow weight loss and putting corrosion in sour gas environments. If severe weight loss or pitting corrosion is encountered, inhibitors have been found to be an effective deter-rent."

Jan 1, 1960

By Y. Chengxian

Many factors about the HIC (hydrogen-induced cracking) resistance of pipelines are discussed in this paper. The main factors that influence the ability of HIC are environmental and material factors. The chemical compositions, non-metal inclusions and microstructure are discussed in detail, while a group of tests on HIC resistance are done according to varying C, S, Mn and P contents in pipeline steels, different experiment time and different strength to the coupon. It is concluded that decreasing the amount of C and S can obtain good HIC resistance; the test time has an effect on the different microstructure of X70; microstructure is the most sensitive factor for the initiation processes of HIC.

Jan 1, 2005