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By Waldemar W. Koczkodaj, William O. MacKasey

A consistency-driven pairwise comparisons method for mineral potential assessment is presented, using a simpli?ed case of volcanic-associated massive sul?de type deposits as an example. Geological, geochemical, and geophysical criteria are considered on two levels: local and regional. The local geological criteria are subdivided into stratigraphy, lithology, alteration and/or mineralization, and structure. The concept of geomerit index and a procedure for computing this index are introduced. The method of consistency-driven pairwise comparisons can be combined with other quantitative and qualitative assessment methods, enhancing them by incorporation of non-measurable geological criteria (e.g., stratigraphy or lithology) and by computation of weights. The consistency-driven approach allows experts to re?ne at-times subjective judgments concerning exploration and land-use planning, and contributes to the improvement of mineral-potential assessments.

Jan 1, 1997

By John D. Godfrey

A brief account of economic developments in and around northeastern Alberta is presented and mention is made of mining and industrial developments currently of interest in the area. Planned and projected operations are briefly discussed for this region. The history of geological surveys and mining activities in the Shield area of Alberta and the adjoining parts of Northwest Territories and Saskatchewan is traced. Reassessment of the presently-known economic picture of northwestern Canada in conjunction with some recent information on Precambrian structures of northeastern Alberta points to some interesting mining possibilities, particularly in and around that province.

Jan 1, 1960

By L. Gutierrez, M. Pawlik

The rheology artificial mixtures of bitumen with fine quartz of varying bitumen content, as well as actual oil sand ores, was investigated under different physicochemical conditions (pH, temperature). All rheological measurements were conducted using a Haake Rotovisco VT550 rotational viscometer, connected to a fixture specifically designed to measure properties of settling suspensions. It was found that at low bitumen contents (1 %, wt.) the pH of the slurries was the most important parameter that controlled the rheology of quartz-bitumen slurries. At higher bitumen contents (10%, wt.), it was a combination of high temperature and high pH that gave the lowest apparent viscosities and yield stresses of the model mixtures. These model observations correlated well with the rheology data obtained for slurries of actual oil sand ores. The overall results were discussed in terms of aggregation-dispersion phenomena between bitumen and mineral particles.

Jan 1, 2009

By J. S. Stachulak

"The main ventilation design features adopted at Inco to safeguard personnel against the effects of fires are described in this paper. Measures taken to prevent and detect fires due to spontaneous combustion, and fires involving conveyor belts, are described in detail.IntroductionConsidering the over-all picture of present-day mining operations, the expenditure required to provide a proper system of mine ventilation and fife control should be regarded as a sound investment that will pay back in increased mining efficiency, improved safety, health, and morale of the miners.Mine ventilation control and mine fife detection and fighting are inseparable, because a ventilation system can spread deadly products of combustion just as efficiently as it does life-sustaining oxygen. Therefore, the possibility of a mine fife occurring is of particular concern.The first objective is to prevent a fife.The second objective is to design the ventilation system so that a positive fresh air supply can be ensured on each main level regardless of the location of the fife.The third objective is to be able to detect the fife at an early stage and to extinguish it before it can develop into a major fife. Accordingly, at Inco, very extensive measures are taken to prevent fires and to locate, isolate and extinguish them rapidly. To obtain an early warning, it is not sufficient to know that a fife has started, but it is also necessary to know where the fife is burning."

Jan 1, 1994

By J. S. Stacbulak

"The main ventilation design features adopted at Inco to safeguard personnel against the effects of fires are described in this paper. Measures taken to prevent and detect fires due to spontaneous combustion, and fires involving conveyor belts, are described in detail.IntroductionConsidering the over-all picture of present-day mining operations, the expenditure required to provide a proper system of mine ventilation and fife control should be regarded as a sound investment that will pay back in increased mining efficiency, improved safety, health, and morale of the miners.Mine ventilation control and mine fife detection and fighting are inseparable, because a ventilation system can spread deadly products of combustion just as efficiently as it does life-sustaining oxygen. Therefore, the possibility of a mine fife occurring is of particular concern.The flirt objective is to prevent a fife. The second objective is to design the ventilation system so that a positive fresh air supply can be ensured on each main level regardless of the location of the fife. The third objective is to be able to detect the fife at an early stage and to extinguish it before it can develop into a major fife.Accordingly, at Inco, very extensive measures are taken to prevent fires and to locate, isolate and extinguish them rapidly. To obtain an early warning, it is not sufficient to know that a fife has started, but it is also necessary to know where the fife is burning."

Jan 1, 1994

By Jean Scott, G. A. Collins, G. W. Hodgson

WHILE it is well known that trace metals in crude •oils and distillates have been a matter of deep concern to refining engineers because of the damage done .by the metals to cracking catalysts and refractories (8, 5), the trace metals in crude oils may be of great benefit in correlation studies and in origin studies. During the geological processes in which the oil is formed from •animal and vegetable life, the hydrocarbons are subjected to a host of inter-related reactions, both physical and chemical. It has been well demonstrated that the lighter materials, certainly the short-chain paraffin hydrocarbons, are degradation products of the heavier molecules, and it might be concluded that for correlation studies it would be advisable to direct attention as much as possible not to the degradation products of the large molecules but to the large molecules themselves. Be this as it may, the methods at •hand to conduct the study are not particularly precise and, in the past, attention has centred on the simpler small molecules, as evidenced by the great mass of work involving distillation and chromatography with painstaking separation of the simpler 'front-end' hydrocarbons.

Jan 1, 1954

By William M. Luff

This paper outlines the regional geology and history of the area, and summarizes the stratigraphy, structure and geology of the Brunswick No. 12 mine area. The Brunswick No. 12 deposit is a stratiform massive sulphide body. It occurs in rocks of the Tetagouche Group, which is believed to range in age from Lower to Middle Ordovician. The stratigraphic sequence, including the stratiform orebody, in ascending order consists of older metasedimentary rocks, augen schist, metasediments, augen. schist, footwall metasediments, the -massive sulphide body, iron formation, hanging-wall metasediments, siliceous tuff, basic volcanic rocks , basic iron formation and a porphyry dyke. This sequence is similar to that at some other deposits in the area. Four phases of structural deformation are known to be present in the Brunswick No. 12 mine area. The first deformation folds (F1 ) and associated faulting are the most important factors in determining the distribution of the massive sulphides. This deformation has resulted in the massive sulphides being separated into four zones: the Main Zone, the West Zone, the East Zone and the V-2 Zone. Brunswick Mining and Smelting Corporation Limited is actively mining, developing and exploring the deposit.

Jan 1, 1977

By X. Gu

Mining operations, especially surface coal mines, have great impacts on the local ecosystem and the environment. However, it has been a common practice in mine design that the economic evaluation considers only the operating and capital costs, while the costs incurred due to ecological damage are left out. Such practice underestimates the total cost of mining and ignores the difference in ecological impacts between different mine design alternatives. With growing interest in sustainable development, the mining industry is under increasing pressure to operate not only based on economic and engineering principles but also on principles of sustainability. Therefore, estimating ecological costs of mining and considering such costs in the mine design process is an important step towards reducing ecological impacts at the design stage. The objective of this paper is to quantify the ecological costs of open pit coal mining and to demonstrate the influence of such costs on the ultimate pit design. The ecological costs of mining are estimated based on the areas and types of land damaged by mining activities and the carbon emission from energy consumption. Four major components of ecological cost are identified, namely, lost value of direct eco-services, lost value of indirect eco-services, prevention and restoration costs, and the cost of carbon emission from energy consumption. Necessary equations are given for estimating these costs. An algorithm is described for ultimate pit optimization in coal deposits with near-horizontal coal seams. A case study is presented in which the ultimate pits with and without ecological costs are optimized and compared to show the influence of ecological costs on the pit design outcome.

Aug 1, 2013

By Claudio Acuña, Sergio Romo, Gerardo Fuentes

The leaching kinetics of a zinc concentrate in autoclave reactors were studied. A sample of concentrate from Bolivia, with typical mineralogical characteristics of the Andes region, was used. A concentrate containing 49% zinc and 145 ppm of silver from Minera Viacha was characterized chemically and mineralogically (atomic absorption, X-ray diffraction, and SEM microscopy) and tested in bench scale reactors. Two types of autoclave batch reactors were used at 40 bars of oxygen pressure and three levels of temperature (150°C, 200°C and 250°C). The solid to solution leaching ratio was 1:10 (10% sulphuric acid concentration). The effect of the particle size of the concentrate on the leaching kinetics was studied (P80: 145 and 45 µm). Iron from the leaching solution was removed by precipitation by increasing the pH in order to generate a clean solution for zinc electrowinning. The zinc solution was used to evaluate the feasibility of cathode production at the laboratory scale. Zinc extractions with higher liberation (P80 = 45 µm) reached up to 98%. Ground concentrate with finer sizes resulted in agglomeration and the use of dispersing agents did not improve slurry mixing. The leaching solution contained 55 g/L zinc and 7 g/L iron; it was purified by precipitating iron. The precipitation was evaluated using sodium hydroxide and ammonium hydroxide. In the first case, a colloidal suspension of ferric salts was formed while in the second case, different iron compounds were precipitated. The precipitate obtained with ammonium hydroxide had better filtering properties. Electrowinning was carried out using two types of cathodes (stainless steel and aluminium) and solutions purified with ammonium hydroxide. Zinc cathodes formed on stainless steel presented a better physical quality than those formed on aluminium.

Jan 1, 2015

By W. W. Rudolph, L. N. Trevani, P. R. Tremaine

UV-visible spectroscopy, Raman spectroscopy, and vibrating tube densimetry have been used in our laboratory to determine equilibrium constants of aqueous species at temperatures as high as 325 °C. The UV-visible and Raman spectra of solutions containing metal complexes and ionized acids or bases can be used to yield formation constants by applying curve fitting methods to resolve the contribution of each species. Colorimetric pH indicators identified by Johnston and coworkers at the University of Texas (Austin) provide an alternative means of determining ionization constants and the pH of complex mixtures. High precision density measurements over the same range yield standard partial molar volumes, which are key parameters for "equations of state" for aqueous species. Examples are given for the copper-ammonia system, simple carboxylic acids, and the iron-sulphate system.

Jan 1, 2004

By R. E. Legg

This paper gives a brief outline of the mining and milling methods which will be used on the Stirling zinc-lead-copper ores by Stirling Mines, Limited, who have for the past two years been developing the Stirling mine in Richmond county, Nova Scotia, and who will bring the mine into production in November, 1929. No attempt has been made to give the paper a detailed technical character, for the main reason chat, since base-metal mining is something new in Nova Scotia, it is felt that a general description would be preferable before this Society, whose membership is mainly made up of chose engaged in the coal mining and associated industries. Furthermore, as both mining and milling operations will be governed to a certain degree by the experience gained after production commences, there are many points which cannot be definitely stated now. GEOLOGY Before discussing the mining methods, it is desirable to present a general picture of the geology and occurrence of the ore-bodies. The surface rocks in the vicinity of the mine consist of rhyolites of .pre-Cambrian age. These volcanic flows outcrop in very few places, usually along' the beds of creeks or on the shores of the numerous small lakes. Consequently, a detailed geological map is not available. The exploration work carried out to date has revealed a sheared zone extending through the volcanic flows for a distance of over 1,000 feet. Along this zone, there has been a replacement of the rhyolites by a carbonate rock for widths varying from 50 to 230 feet, and it is in this carbonate formation chat the mineralization at a later date took place.

Jan 1, 1929

By M. Tiedtke, T. Crary, P. MacPhail, M. Ounpuu

"The SGS carbon-in-pulp (CIP) / carbon-in-leach (CIL) model was used to evaluate and optimize the carbon circuit at Alamos Gold’s Young-Davidson Mine. Plants samples (pulp and carbon) were tested in a series of small scale batch experiments to determine rates of gold leaching and adsorption on carbon from a combined flotation concentrate/tailing product. The testwork data, along with existing plant data were then used to model the performance of the existing CIL plant and optimize the circuit to improve performance and overall recovery. The primary purpose of the modelling exercise was to determine the most cost effective way to lower solution losses at the plant. The modelling was also used to learn how the various parameters in the CIL circuit affect solution losses and the gold inventory tied up on the carbon. This resulted in recommendations for minor changes in the CIL flowsheet, which were successfully implemented in the plant. The approach, results and plant changes are presented.INTRODUCTION This paper presents the details from testwork conducted on samples from Alamos Gold’s Young- Davidson gold mine which is located near the town of Matachewan, approximately 60 km west of Kirkland Lake in Northern Ontario, within the southwestern part of the Abitibi Greenstone Belt. The objective of the test program (completed by SGS Canada in 2013) was to investigate and model the combined flotation concentrate / tailing carbon-in-leach (CIL) circuit and suggest ways to improve gold recovery. The metallurgical test program included mineralogy, rheology, and carbon modelling testwork. Plant information was provided during the test program and used in the optimization process. Upon completion of the testwork, plant changes were recommended and implemented at site (October 2014). Plant results from 2014 to 2017 confirmed the modelling results."

Jan 1, 2018

By J. E. Quinn, S. Wolstencrof, K. H. Soldenhoff

Ion Exchange (IX) using Strong Base Anion Exchange (SBA) resins is conventionally used to purify uranium from sulfuric acid pregnant leach solutions (PLS), particularly when uranium grades are relatively low. However, the presence of chloride in the PLS interferes negatively with conventional SBA based IX processes, by reducing the uranium loading on the resin. Chloride can be present in the PLS due to the use of saline bore or seawater in leaching, or chloride containing leach/IX reagents. ANSTO has been examining strategies to combat this problem for several years. ANSTO previously reported that a recently developed high-capacity SBA resin was capable of extracting uranium efficiently from saline leach liquors produced at Boss Resources’ Honeymoon in-situ recovery mine in South Australia. The resin was tested successfully in a 2017 Field Leach Trial carried out onsite in the existing wellfield area. While the piloting was extremely promising, the elution was more challenging, with eluate tenors limited to 2 g/L U3O8 using NaCl. This is due to the resin’s strong affinity for the uranium complex, which makes it difficult to elute efficiently by standard methods. In this paper, we describe a novel elution process developed for strong base resins that significantly improves upon conventional methods. The process, developed by ANSTO, is based upon conversion of the extracted uranyl sulfate species to uranyl carbonate, followed by elution with sodium chloride. The loading and elution process was demonstrated in continuous locked-cycle piloting conducted at ANSTO in 2019. The results were excellent, with eluate tenors of 8–9 g/L U3O8 achieved from Honeymoon PLS containing 50 mg/L U3O8, with very little transfer of impurities. In subsequent test work, the eluate was shown to be amenable to uranium peroxide precipitation. The results represent a huge step forward for the purification of uranium from saline leach liquors.

Jan 1, 2020

By H. Oterdoom, S. Pilger, T. P. Bui, J. Rotarius

"Most FeNi furnaces used to rely on post-combustion and off-gas cooling inside the furnace to eliminate the produced CO gas, and control the off gas temperature. As furnace load, capacity, and thus gas volumes increased over the years, this led to increased instabilities that can cause problems in controlling the operation. Some of the large capacity furnaces nowadays work with partial or full combustion outside the furnace, more similar to the steel industry. Forced combustion with or without enriched air and other additions can support in controlling post-combustion, stabilizing and even reducing off gas amounts, and affecting composition. This paper presents some of the possibilities and advantages of having a specially designed post-combustion system for the FeNi laterite industry, but that could also be applied to other processes as well.Large Scale Furnaces In the FeNi industry, the Rotary Kiln Electric Furnace (RKEF) process is still going strong in spite of continuous hope that hydrometallurgical processes will one day make the RKEF plant obsolete. Within the pyrometallurgical plants there is a continuous trend for larger scale furnaces. The development for a number of furnaces that were started before 1985 and increased capacity by “natural growth” is given in Figure 1. Natural growth refers to the development of the plants that after having mastered a certain level of operation, were ready for a higher load that could be installed either with a new furnace on the same site, or during a revamp. The advantages of natural growth are numerous, for example: •,Deep knowledge of the ore and its’ behavior, no need for testing, and little risk of surprises. •,Mining, laboratory, equipment, etc. is all proven technology for the conditions on site. •,Starting a furnace with increased capacity is a re-start, not a green-field commissioning. •,Typically, when increasing the production capacity of an existing plant, not the entire plant is commissioned for the first time, but only a part. In the FeNi laterite industry for example, the kilns may already have had the capacity to provide enough material."

Jan 1, 2017

By B. R. Boardman

Project Environmental Approval is a multi-faceted issue. From a mining perspective, it is a costly item because of avoidable time delay. The government perspective is that the approvals are a necessary part of meeting departmental requirements to ensure that the wellbeing of other uses of the environment is maintained. This paper outlines some of the problems inherent in the environmental approvals process and makes recommendations to both the proponent and government about improving the efficiency of the process.

Jan 1, 1978

By Graham Walker

A new Code of Practice for the brake performance of off -highway vehicles was established in Alberta in 1976. Vehicles loaded to gross vehicle weight must be capable of stopping with mechanical brakes five times in quick succession on a grade of 10 per cent from a speed of 28 miles per hour. Comparative trials of various brake systems have been carried out and some combinations capable of meeting the Code are identified. Some problem areas in truck braking are reviewed and potential developments indicated.

Jan 1, 1977

By K. Morin, C. -Y. Hon, G. Lachapelle

"Air-sampling results suggest drill operators working inside environmental drilling cabs at an open-pit gold mine in Nunavut, Canada, are at risk of exposure to asbestos and silica (quartz). The authors installed RESPA® CF Vortex HyperFLOW® units, which showed promising results under laboratory conditions. The goal was to evaluate the effectiveness of these units under actual working conditions. Personal and area air sampling was conducted in drilling cabs with and without the unit and a Wilcoxon rank-sum test was performed to compare the results. Particulate concentrations were significantly lower in drill cabs with a unit installed than in those without.RÉSUMÉ Selon les résultats d’une campagne d’échantillonnage de l’air, les foreurs travaillant dans des cabines de forage environnemental dans une mine d’or à ciel ouvert du Nunavut, au Canada, risquent d’être exposés à l’amiante et la silice (sous forme de quartz). Les auteurs ont installé des unités RESPA® CF Vortex HyperFLOW®, lesquelles of frent des résultats prometteurs en laboratoire. L’objectif est d’évaluer l’efficacité de ces unités dans des conditions de travail réelles. Des échantillons de l’air inhalé par le personnel et dans les aires de travail ont été évalués dans des cabines de foreuses équipées ou non de cette unité ; un test de Wilcoxon (également appelé test de la somme des rangs de Wilcoxon) a été mené afin de comparer les résultats. Les concentrations particulaires étaient considérablement plus faibles dans les cabines de foreuses équipées d’une unité que dans celles en étant dépourvues.INTRODUCTIONGenerally, mining operations are associated with a variety of occupational hazards. In an open-pit gold mine in Nunavut, Canada, drill operators are routinely exposed to asbestos (primarily amosite) and silica (quartz)—two naturally occurring substances in the ore that is to be drilled (Table 1). Inhalation is the primary route of exposure for these two hazards, which are associated with respiratory health effects such as asbestosis and silicosis, respectively. In addition, asbestos and silica are classified as human carcinogens by the International Agency for Research in Cancer (2001, 2011). Given the toxicity of these two agents, it is imperative that precautions be taken to minimize the risk of exposure of the mine’s workforce. To address this matter, the mine has an exposure-control plan, which includes the provision of personal protective equipment, personal hygiene facilities, training, and a medical surveillance program. Furthermore, the mine performs occupational exposure assessments or air sampling on a regular basis because the morphology of the ore changes rapidly with respect to asbestos and silica content."

Jan 1, 2017

By C. Mawdsley

The Tata Steel mill at Skinningrove in the North East of England produces top hat sections for mineshaft guides in sizes 102 and 150 mm. The top hat section is the technically preferred shaft guide choice for modern deep mine shafts. This paper explores the relative service performance of top hat and square hollow section guides in service. Comparative corrosion performance is reviewed and the paper describes work commissioned by Tata Steel (as Corus) undertaken by Aker Kvaerner Engineering to evaluate relative winding speeds, relative loads and fatigue life in service. The experience of supply to UK Potash mining is discussed and the future view of high capacity hoisting and larger section size market need and availability is assessed.

Aug 1, 2013

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 Adrian Dance

The Antamina orebody is a geologically complex, polymetallic skarn located in the Peruvian Andes. A range of copper and copper-zinc ores are campaigned separately through the concentrator producing copper and zinc concentrates as well as lead and molybdenum by-products. Ore type classification at Antamina is based on chemical assays; geological or lithological variations are not considered. Consequently, each ore type demonstrates a wide range of concentrator performance. Antamina is currently implementing a system to track ore movements from the shovel face to the concentrator. Relatively sophisticated models of the ROM and coarse ore stockpiles ahead of the mill will be used to account for the variable delay between mining and milling. One of the numerous benefits of ore tracking is the ability to directly associate the measured concentrator performance with a physical location in the orebody. Using existing mine planning software, three-dimensional models can be created of such performance measures as metal recovery, concentrate quality, operating cost and reagent consumption. Such a database of information allows the true value of different ore sources to be determined. The value of an ore source is conventionally measured as metal content (individual or combined ?equivalent?) with a cut-off grade applied to indicate some base level operating cost. However, the true value of an ore source should include dynamic factors like haulage cost, reagent use, smelter penalties and even prevailing metal prices. If an ore source is considered from all perspectives rather than simply its potential to deliver value, the concept of ?ore? becomes more flexible. Any ore source that reveals itself to be unprofitable can be eliminated from the mine plan or possibly blended with others to improve its value. The ability to predict mill performance ? and thereby profitability ? is a powerful tool. In an operation such as Antamina, where managing ore sources, campaigns and the delivery of a variety of concentrates in a narrow timeline to customers is a daily challenge, prediction is the key to success and improved efficiency.

May 1, 2003