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By P. F. Berry

X-ray fluorescence analytical techniques are fairly well established in the mining and metallurgical industries. In recent years, instruments utilizing radioactive isotopes have been developed which, owing to their more compact size, greater reliability and independence of substantial power supplies, are often preferred to X-ray tube installations. Analyses can now readily be carried out in the field, on the factory floor and in otherwise difficult locations. This paper describes many examples of radioisotope X-ray fluorescence for the analysis of metallic minerals, finished metals and alloys and also for the continuous measurement of metallic coatings, such as tin and zinc, on steel. Radiation scatter techniques are also described for certain analyses and for thickness and density measurements.

Jan 1, 1967

By B. A. Strathdee

An arsenical ore containing both pyrite and arsenopyrite was heated to a temperature at which decomposition and distillation took place. The condensate consisted of metallic arsenic and arsenic disulphide, although the analysis of the ore showed that volatile arsenic and sulphur were present in proportion to produce a condensate of arsenic trisulphide and sulphur. Distillation tests on the mineral arsenopyrite also produced a condensate of metallic arsenic and arsenic disulphide. This arsenic sulphide gave a distinct x-ray diffraction pattern which was not listed in the A.S.T.M. data file. This same sulphide can be produced by heating a mixture of arsenic and sulphur in vacuo. Its chemical analysis corresponds to As2S2. The dissociation pressures of arsenopyrite and the vapour pressures of arsenic disulphide and arsenic metal were measured, using a quartz "spoon" gauge. The dissociation pressures of arsenopyrite were compared with the published data for the dissociation pressures of pyrite to account

Jan 1, 1961

By H. Zhu, Q. Jiang

The leaching kinetics of iron during the atmospheric direct leaching (ADL) of marmatite concentrate was studied under the following conditions: reaction temperature of 343-383 K, slurry pressure of 0.3-0.7 MPa, particle size of (-74 ?m, +63 ?m), (-63 ?m, +44 ?m), (100%-44 ?m). The statistical effects of reaction temperature, total pressure and particle size of concentrate on the extraction and the leaching rate of iron were analyzed. The results show that reaction temperature is a significant factor while slurry pressure and particle size are not statistically meaningful with respect to the extraction or the leaching rate. The extraction of iron fits better to the mixed-controlled shrinking core model and the apparent activation energy was calculated to be 37.66 kJ/mol. The leaching of iron is mixed controlled by the interfacial chemical reaction and diffusion across the product layer.

Jan 1, 2014

By D. B. Stewart

In the past few years, much effort has been spent in elucidating the impact of diesel engines on the mine environment. This paper summarizes diesel fundamentals , exhaust emissions and typical tailpipe concentrations. Mine sampling results and an evaluation of exhaust treatment systems are discussed. A review of changes in pollutant concentrations between the tailpipe and the mine exit is made and suggestions are given to reduce operator exposure to diesel contaminants.

Jan 1, 1978

By R. S. Douglas

Introduction During the past few years, a number of changes in the mine operations at Copper Mountain have taken place. The modernization and mechanization were necessitated and given impetus by wartime and other conditions, which were: (1) The urgent need for copper for wartime purposes. (2) The scarcity of skilled labour for underground work. (3) The increase in labour and supplies cost. (4) The necessity of finding ways and means of increasing the output per man-shift, because of the scarcity of skilled labour and the rising cost of labour. (5) The desire to increase safety measures, reduce the silicosis hazard, and aid mine ventilation. (6) The desire to improve the general working conditions in the mine for all workmen. (7) The desire to reduce the amount of dilution in the ore stream by a more selective yet highly productive method of mining. To this end, mining with diamond drills, and transferring broken ore with slusher hoists, appeared to be the answer to the problem. After considerable discussion and estimation of costs for comparison with those of the operation as carried on at that time, the proposed methods were tried out and, in practice, gave very gratifying results. Reference at this point is made to the paper written by C. H. Brehaut, W. N. Taylor, H. A. Shannon, and R. S. Douglas, which was published in the September, 1945, issue of Mining Technology, by the American Institute of Mining and Metallurgical Engineers, Inc., and subsequently in commercial mining journals. Since that time some improvements have been made in undercutting an orebody - the first through experiment and practice, the second through making use of the earth's barodynamic or gravitational forces. It is the purpose of this paper to describe and discuss these later developments.

Jan 1, 1947

By Ray Mason

Marathon PGM Corporation?s PGM-Cu Project in Northwestern Ontario (Figure 1.0) serves as a case study to describe the process involved in advancing a deposit from grass roots exploration to the completion of several feasibility studies and the parallel commencement of environmental permitting. Through the following examination of historical exploration activities, it is clear that these activities are directly related to economic stimulus, mostly measured by downturns in the mineral industry. Other factors that influence the success of exploration advancing to feasibility and new mine development includes the ownership of the mineral claims, which also changes under these economic influences and the crucial role of interactions between the Company, the Crown and First Nations. The Marathon PGM-Cu deposit is hosted within the Eastern Gabbro Series of the Proterozoic Coldwell Complex, which intrudes and bisects the much older Archean Schreiber-Hemlo Greenstone Belt. The sub-circular complex has a diameter of 25 km and a surface area of 580 km2 and is the largest alkaline intrusive complex in North America (Walker et al., 1993). Mineralization at the Marathon PGM-Cu deposit is part of a very large magmatic system that consists of at least three cross-cutting intrusive olivine gabbro units that comprise the Eastern Gabbro Series of the Coldwell Complex (Figure 3.2.4-3). In order of intrusion, the three gabbroic units consist of (1) Layered Gabbro Series, (2) Layered Magnetite Olivine Cumulate (LMOC) and (3) Two Duck Lake (TDL) Gabbro. The relative size and abundance of the gabbroic units decrease in the order Layered Gabbro Series>TDL Gabbro>>LMOC. Late quartz syenite and augite syenite dikes cut all of the gabbros but form a minor component of the intrusive assemblage.

May 1, 2010

By J. Visman

The water cyclone washer has a number of advantages that makes it a desirable machine for the cleaning of fine-grained and friable materials such as 1,4 x 0" slack coals. In this paper results are presented of tests carried out on a shaly coal containing a high percentage of inter-grown materials from the Minto area, New Brunswick. The tests were con-ducted in the pilot plant of the Western Regional Laboratory in Edmonton. The test results show that the cleaning characteristics of this coal can be improved by lightly grinding the recirculating middlings fraction, which constitutes approximately 30 per cent (1.45-2.00 fraction) of the raw feed. • The cleaning of 1;4 x 0" fines by water cyclones compares favourably with other coal cleaning machines and has an added advantage of being extremely simple to operate, low in capital and operating cost, and high in capacity. The application of water cy-clones dates back approximately ten years, following its development at the Dutch State Mines. ( 3) A number of papers published d

Jan 1, 1961

By K. L. Ford, D. R. Lentz, J. H. Rickard, R. P. Taylor

Abstract - Coupled gamma-ray spectrometric and lithogeochemical studies throughout the Heath Steele Mines area, Bathurst Camp, New Brunswick, indicate that primary and secondary geochemical differences exist between the stratigraphic footwall and hangingwall crystal tuff units which host the massive sulfide deposits. Of particular interest is Th, and to a lesser extent, Zr and Y, which are more concentrated in the hangingwall than the footwall crystal tuffs, whereas the opposite is true for TiO2. This expands on earlier lithogeochemical-chemostratigraphic results concentrated in the eastern part of the Heath Steele belt that led to revision of the local stratigraphy, and necessitated a structural re-interpretation of the area with implications for exploration. Although K depletion (decreased K and K/Th) is typical of chloritized footwall zones of chloritization, these features were not fully apparent here due to the recessive nature of these altered zones. In situ radiometric analysis using a portable gamma-ray spectrometer is a rapid, inexpensive analytical technique for chemostratigraphic characterization of rock units within volcanogenic massive sulfide deposit settings, provided there is a contrast in the distribution of natural radioelements, particularly Th and K.

Jan 1, 1998

By George Delorme

"AbstractThe basic intention of this paper is to present, from a practical viewpoint, a thorough outline of all the sound and accepted principles connected with attaining satisfactory rope performance from multi-rope friction winders.In order to emphasize the importance of some aspects of rope maintenance, a limited amount of hoist rope theory has been included, a s it is felt that without this, some of the more critical, but nevertheless practical, aspects would perhaps pass without full appreciation of their individual merit.It is very much appreciated that many of the maintenance topics and practices discussed herein are already being observed with a high degree of skill among those already involved in modern friction winding. The hope is expressed, however, that the paper will be of additional assistance, and of particular help in introducing sound maintenance principles to those who are moving into this field of operation for the first time.Hoist RopesWITH a multi-rope friction winder system, structural upset within the hoist rope's cross section can occur if the ropes slip in the drum treads. This upset will usually appear at either end of the rope at the tangent point of the drum or deflection sheave with the respective conveyance in the normal uppermost position. This slipping action on the drum causes the outer cover of a Full Locked Coil or the strands of a stranded rope to shift, leading to structural upset. The result very often means that the ropes have to be withdrawn from service before completing their maximum service potential.The cause of any rope slipping in its tread can be associated with a discrepancy in tension of that rope between one side of the drum and the other."

Jan 1, 1977

By G. Reuben Yourt

IN 1935, Wright-Hargreaves Mines, Limited, initiated an enlarged programme of ventilation. In the mine, surveys were made from time to time by the geological staff, and improvements in ventilation were effected to accord with progress in mining as greater depth was attained. In the summer of 1938 an engineer was trained in the technique of dust sampling. Instruments and equipment for this purpose, such as konimeter, microscope, furnace, etc., were purchased, and a suitable office, equipped with laboratory facilities, was provided. The full time of the engineer is devoted to ventilation and dust control. On surface, in the mill crushing-plant and in the assay office and sample crushing room, an elaborate arrangement of hoods and exhaust systems has been installed to eliminate the dust. These installations, however, are not described in the present paper, which deals only with an extensive programme of underground ventilation as a method of coping with high dust concentrations, increasing temperatures and high humilities.

Jan 1, 1940

By Jesús L. Valenzuela, José R. Parga, Salvador Aguayo, Héctor Moreno

The Merrill Crowe zinc-precipitation process has been applied worldwide on a large number of operations for the recovery of gold and silver resulting in a higher consumption of zinc dust from cyanide solutions. However, in some of plants this precipitate is of low quality, because lead, cadmium and especially copper are precipitated along with gold and silver. The low quality precipitate also requires more fluxes in smelting and shortens crucible life. In this study, a process is introduced to remove copper, silver, lead and cadmium from barren solutions following the Merrill-Crowe process. Copper and silver are removed by precipitation in a serpentine reactor, using sodium sulfide as the precipitator, and sulfuric acid for pH control. The recovery of lead and cadmium ions with natural hydroxyapatite using cow bone powder (CBP) as a new adsorbent material, is introduced. CBP is capable of removing lead and cadmium ions from aqueous cyanide solutions with 99% efficiency. It has the ability to compete with other existing commercial adsorbents for the removal of lead and cadmium. Results show that pH value has a significant effect on copper cyanide removal efficiency, and it was determined the optimal pH range to be 2 - 3. At this pH value, the copper cyanide removal efficiency achieved was up to 99 %; and for the cyanide associated with copper cyanide complexes, the recovery was 90%. Finally, the precipitate quality was improved 400% .This procedure was successfully run at three mines in México.

Jan 1, 2014

By Robert G. Boutilier

So far, most social performance monitoring systems have not gone beyond listing the impacts on various stakeholders. Executives have had to rely on intuition to devise interventions that would improve the impacts. This paper describes a survey process, known as the Stakeholder 360 (S360), which eliminates much of the guesswork. The paper reviews key studies showing that raising the levels of communication, trust, and common vision among stakeholders leads to the acquisition of the resources needed to improve the socio-economic situation. Therefore, the Stakeholder 360 measures the levels of these three factors in the relationships between a company and its stakeholders, and among the stakeholders themselves. In a validation study at a gold mine in rural Papua New Guinea, the S360 produced a socio-political ?roadmap? that showed management and stakeholders alike which relationships need more communication, trust, or common goals/vision. Management used the findings to create alliances that helped the government move forward on a regulatory regime for the mine closure. The community used the findings to focus its planning for life after the closure. An S360 survey conducted six months later revealed a decline in dependence on the mine and an overall increase in levels of mutual understanding.

May 1, 2002

The major factors limiting the establishing of vegetation on the shale and sandstone wastes at Minto are high exchange acidity and low pH (shale pH 4-5, sandstone pH < 4). In the first revegetation program (1967-74), 3.8 million trees were planted without grading on 4,000 acres (red, jack and scots pine and black locust). White dutch and sweet clover, birds-foot trefoil and red top were established in selected areas, and ponds were stocked with brook trout. In the second phase of reclamation, beginning in 1979, a comprehensive plan will be initiated which will allow for forest production, wildlife development and recreational activities.

Jan 1, 1977

By A. Christoffersson, T. Nillson-Wullf, H. R. Manouchehri

"Mining industry has been the building blocks for human development through millennia and will continue to play its role in sustainability and meeting society’s needs for raw material. In the way towards sustainability, the next generation of efficient and heavy duty of Sandvik’s crushers, CH860 and CH865, are introduced for efficient crushing. As the secondary, tertiary and/or pebble crusher, these new crushers are designed to over perform in tough mining environment. Featuring higher crushing forces relative to the mantel diameter and 500 kW motor, combined with advanced automation system, i.e., sophisticated HydrosetTM and Automated Setting Regulation (ASRTM), combined with overpressure system with dedicated air supply in dust collar, etc., the new crushers provide higher safety, productivity, and reliability with the same foot-print of conventional cone crushers.Since crushers are more energy efficient than mills it makes sense to effort in fine crushing to save energy and protect environment. That has been the logic behind development and introducing stronger and more efficient crushers by Sandvik. The results on crushing hard iron and gold ores by CH865 have proven its efficiency in fine crushing at a higher productivity, availability and reliability rates through increasing throughput for defined size fraction and extended crushing chamber liner life.Within this paper the performance of the CH865 to deal with two different ores are presented discussed with a glance at how the downstream milling process can be benefited by saving energy and reducing the operation cost. In plant practice, the implementation of the new CH865 provides between 25 and 30% of the crushed ore in the size range of first step milling, i.e., < 2 mm, that offers opportunity for reduction in energy consumption in milling and even changing the process plant configuration by directly forwarded that part to gravity separation. Furthermore, potential of converting the rod mill to ball mill to improve productivity has been considered by plant engineers. Furthermore, some potential applications for such efficient crushers are brought into considerations and discussed. The new developments provide about 30% higher crushing force to efficiently deal with competent ores and pebbles. The CH860 and CH865 crushers are well suited to replace conventional secondary and tertiary crushers respectively; nevertheless, CH865 is virtual option for pebble crushing in SAG and AG milling circuits."

Jan 1, 2016

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 A. Eslami

When producing high grade mattes in smelter plants, copper losses in the slag are inevitable. Hence, the recovery of copper from slag has been the focus of many research projects, copper flotation being a widely used process. In the Khatoonabad converter, 200 t/d of slag are presently produced with a grade of 2.3% Cu. Assuming a 85% recovery by flotation, about 3.9 t/d copper could be produced, which is of prime importance economically. In the present work, a sample of this slag was crushed and ground in the laboratory to liberate the copper-bearing minerals. Following mineralogical studies, optimum laboratory flotation parameters were obtained, resulting in 90.27 % recovery and 9.42% of copper grade for the rougher stage. At pilot scale, a pulp of 28% solids was floated at ph 10.5 using 40 git of Z6, 25 git of R407 and 20 git of MIBC and A65. A recovery of 83.52% was obtained for a concentrate grade of 28.36% Cu. In the rougher cells, the feed consisted of particles 94% finer than 74 microns whereas in the cleaning stage, particles were 95% finer than 44 microns. Based on the obtained results, the Sarcheshmeh Khatoonabad converter slag is presently being fed to the Chargonbad flotation plant, where a concentrate of 32% copper at 86% recovery is being produced.

Jan 1, 2007

By H. Wotruba, L. von Ketelhodt, M. Kowalzcyk, M. Robben

ABSTRACT Decreasing reserves, water shortages, increasing energy costs, and environmental and social constraints are challenges to the gold mining industry that must be met with innovative machines and methods. This paper introduces the principles of sensor-based sorting and installations that demonstrate the technical and financial viability of the method. The scenarios discussed highlight the potential and advantages of this dry processing technology that requires little infrastructure. Case studies are presented for different ore types using optical- and X-ray transmission–based sorting. Current research is discussed in terms of the potential of near-infrared spectroscopy and X-ray fluorescence sorting for gold applications.

Jan 1, 2013

By Chris M. Healey

"Abstract- The Jasper Gold mine in northern Saskatchewan produced a total mill feed of 140 127 tonnes at an average grade of 19.0 g/t Au. Both diamond drilling and chip samples from under­ ground workings returned extremely high values, up to 12 851 g/t (375 oz/I) Au over 0.10 meter from a chip sample. In the presence of such extremely high grades, the accurate estimation of reserves is a major problem.ln the first part of this study, production data from the mine were used to evaluate the results of a variety of reserve estimation techniques in this environment. In two out of three cases studied, indicator kriging with assays cut to 342.9 g/t (10 oz/I) gave extremely good results. In the third case, however , indicator kriging gave unacceptable results. Instead, lognormal kriging of uncut data gave the best results.Secondly, from the same database, a number of drill-hole spacings were simulated, and reserves estimated from the simulations. As may be expected, the results of this analysis show increasingly better results with tighter drill-hole spacing. However, even with a 5 m by 5 m spacing the variation from actual grade was quite large. This is not a systematic under- or over-estimation of grade, rather a random scatter of results .The results of this study show very clearly the problems of deriving good estimates of reserves when extremely high-grade samples are encountered. There is a high degree of randomness to this database, so reserve estimation in this situation will remain a high-risk operation."

Jan 1, 1993

By W. A. Lang

"I.-IntroductionAn attempt bas been made in this paper to provide a basis for appraisal of the future of the coal briquetting industry in Alberta by outlining the processes used for briquetting various ranks of coal, by specifying the requirements of a briquetted fuel, by indicating .the status of the industry in the United States, by giving developments in Western Canada, by assessing costs of processing, and by discussing briquetting researches in progress. Much of .the detail bas been omitted since this might mask, rather than reveal, the more important phases of the problem. Reference will be made when possible to published articles where many of the details can be obtained.It should be stated at the outset that, in the writer’s opinion, there are three possible developments in Alberta as regards briquetting: (a) an expansion of the briquetting of the fines of • non-coking and coking coals of semi-anthracite, and of low and medium volatile bituminous rank; (b) the processing of the fines of high-volatile C bituminous coals; and (c) the upgrading of the lower rank high-moisture sub-bituminous coals. Details of the chemical and physical properties of these coals can be obtained in publications of the Research Council of Alberta (1, 2), and of the Fuel Research Station, Bureau of Mines, Ottawa (3).Semi-anthracite and low and medium volatile bituminons coals occur in the mountain areas of Alberta, where, during the upthrust of the Rocky mountains, the coal beds served as the sliding surface. This resulted in the coals being; crushed and consequently they contain a h1gh percentage of fines. In some cases they are high in mineral matter and require to be cleaned before being processed. However, the cleaning of fine coal is both difficult and costly. Both the amount of fines present in the mine-run coal and the amount of mineral matter associated with the coal have increased through the introduction of mechanized mining and through the recovery of coal by stripping operations."

Jan 1, 1950

By C. Bergstrand

"Precipitation of gypsum and the formation of scale may pose a serious challenge in the leaching of several minerals. As an example, precipitated gypsum may form scale in the machines increasing the need for maintenance. Alternatively, it may encapsulate precious elements, i.e. gold and lower the recovery during subsequent leach processes. In this work we explore how different biopolymers modify the rheology of gypsum at three different pH levels at ambient and elevated temperatures. The ability to disperse gypsum vary with temperature, pH and biopolymer. It is also inversely related to the scaling potential. Measurements of the zeta potential as a function of increasing amounts of biopolymer reveals that the magnitude of the zeta potential changes in the presence of biopolymer, and so does the ability to disperse the gypsum suspension. Similar results with hematite will also be discussed. The methodology and results may aid in the selection of additives used in mineral processing applications where scale pose a problem.INTRODUCTION Processing of refractory gold ores normally involve either atmospheric or oxidation under pressure in order to convert sulfides to oxides (Weir, King, & Robinson, 1986; Weir, Robinson, & King, 1986). This conversion facilitates leaching of gold (and silver) in normal CIL processes. During oxidation, sulfides are converted to sulfates. Normally, there is an abundance of calcium ions in the process water, either released from the ore or added as lime to adjust pH for the CIL process. Precipitation of calcium sulfate, or other compounds (calcium carbonate, jarosite, hematite) is a way to remove gangue minerals from the solution entering the CIL circuit (Ji, King, Fleming, & Ferron, 2010). Precipitation may also cause challenges in the process as gold (or other valuable elements) may become encapsulated in gangue. (Beauchamp, Choung, & Xu, 2006). In addition to precipitation, the precipitated gangue minerals may solidify and form scale in the processing equipment. Recently, Lauten and Kluck (2016) found that dispersants used as scale inhibitors to prevent encapsulation of gypsum did not modify the solubility of gypsum. In the utilised model system, similar amounts of gypsum precipitated with and without dispersants. Instead, it was found that the dispersants evaluated as scale inhibitors reduced the yield stress of gypsum suspensions. The reduced yield stress was associated with a reduced tendency for gypsum particles to agglomerate and form scale."

Jan 1, 2017