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By P. D. P. Hamilton

IT is perhaps obvious to most individuals who are interested in the mining industry that a producing mine has been subjected to several phases of engineering attention. In this paper it is the author's hope that a thoughtful survey of these various engineering phases will emphasize certain points of value and interest which may sometimes be overlooked. The points which we will bring out are being made in an analytical sense and are not in any way a reflection on any individuals or organizations which might see in these illustrations a similarity co chair particular conditions. In other words, we are drawing on our general experience to illustrate the points which we chink are worthy of mention, and which we believe are of a type sufficiently frequent co be emphasized. It is well co point out chat, in this paper, we are not concerned with the relative importance of such theoretical questions as to whether or not a geologisc is more important than a prospector, or the office manager than the surface foreman. We are, however, interested in analyzing the various types of engineering experience required in the bringing of a mining enter-prise from the early prospect stage in co-production, and their importance to the project as a whole. In order to simplify our analysis of the subject, it has seemed best to outline a simple mining organization. In using the terms 'industry' and 'business', we feel chat frequently those engaged in mining do not always appreciate that mining is actually an endeavour, or a business, which has the same economic fundamentals as any other business. In the mining industry, the field and producing engineering are counter-parts of the research and production phases of any other type of business. Once this is realized, it is fairly obvious that mining, like any other industry, is a matter of economically acquiring raw materials, processing them, and finally marketing the resultant commodities as favourably as possible. The points may be discussed in a little more detail as follows.

Jan 1, 1938

By V. “Ram” Ramachandran

"In view of the increasing number of environmental regulations that have been promulgated all over the world in the last thirty years, non-ferrous smelters and refineries have had to learn and adapt to treating process bleed waste streams containing heavy metals. The result of such treatment invariably yields a gypsum-saturated solution containing salts such as alkali metal sulfates, chlorides and fluorides. Presence of anions such as sulfates, chlorides and fluorides in the discharge streams – presently not a major problem- are coming under increasing scrutiny and will have to be addressed in the near future. It is envisaged that discharge limits for sulfate ions will be in place in the near future. Treatment of brackish water to produce drinking water also results in brine streams containing alkali salts that have to be addressed for proper disposal. This paper reviews treatment options for such streams containing high levels of total dissolved solids with emphasis on sulfate removal. Areas covered would be: a) chemical treatment for removal of various constituents that make up the total dissolved solids b) processes for sulfate removal processes –thermal and non-thermal-to recover and reuse of treated water and c) brine use and treatment options.INTRODUCTIONThe rising cost of water and meeting the ever-changing stringent environmental discharge regulations make water recycling and reuse essential. The metallurgical industry has used water as a medium for dissolving and/or rejecting metals and chemicals in addition to removing thermal energy. Any excess process effluent is collected and sent to end-of-pipeline treatment and ultimately discharged to surface water for disposal under a permit. The conventional- and probably the cheapest way -of treating metal-bearing process effluent streams is lime neutralization followed by sulfide polishing for elimination of heavy metals to produce a stream that meets NPDES discharge limits. This results in a stream containing dissolved solids.These dissolved solids normally comprises of inorganic salts. The possible constituents are cations calcium, magnesium, sodium and potassium. The anions are sulfate, chloride, fluoride, nitrate, carbonate and bicarbonate. In addition to these constituents, the treated effluent streams contain very small amounts of heavy metals, oxyanions such as arsenites, arsenates, selenites and selenates. Process streams from gold operations contain residual cyanide. Small amounts of ammonium ions are also present in these streams based on the pH of the solution."

Jan 1, 2012

By Kevin C. Milne

"The solution of problems associated with development of a sour gas reserve will be of increasing importance in tl1e next few years if gas export is approved •by the National Energy Board. The purpose of this paper is to review briefly the history of the Carstairs gas field, and tCI describe in a general manner the reservoir, and the producing and processing facilities.HISTORYThe Carstairs gas field was discovered in April 1958 when the discovery well, Home Carstairs 10-17, was successfully completed as a gas well in the Elkton member of the Turner Valley formation. Geo-graphic location of the field is shown in Figure No. 1. Note that the field is about five miles west of the town of Carstairs, Alberta, which in turn is about 40 miles north of Calgary. Drilling subsequent to the discovery well resulted in three addition-al producing wells and one dry hole during I.958; two producing wells during 1959; and one producing well and one dry hole during 1960. Thus, seven producing wells and two dry holes have been drilled in the Carstairs field to date.In November 1959 a 12-section block in the Carstairs field was unitized on a surface acre basis. Mean-while, in June 1959, operators in the field executed an ""Interim Plant Agreement"" that provided the money needed to start construction of a joint venture processing plant and gathering system. Construction of the plant and gathering system was completed in February 1960."

Jan 1, 1960

By W. Griffith

"While oxalic acid precipitation practices are commonly applied on purified rare earth elements (REEs) pregnant leaching solutions (PLS), few efforts have been reported using oxalic acid (OXA) to recover REEs directly from untreated PLS. High oxalic acid demand is the most significant issue in all these direct oxalic precipitation (DOP) practices. Preliminary research on DOP of REE from a dilute PLS originating from an acid bake followed by water leaching was conducted. At 75°C, the oxalic acid demand was between 12 and 18 times the stoichiometric requirement for complete REE precipitation. Conducting DOP at 25°C had superior REE recovery but the product purity and filterability declined. Between 75°C and 100°C, REE recovery increased with increasing temperature. When sodium hydroxide was used to adjust the pH during DOP, in the range of 0.5 to 1.5, higher pH benefited REE recovery. Using ammonium hydroxide in place of sodium hydroxide, the REE recovery was reduced by close to 5%. Sodium chloride addition to the PLS was also investigated and the results showed that at both 75°C and 25°C, the REE recovery was enhanced substantially. At 25°C, when the oxalic acid addition was controlled at 4.7 times the stoichiometric requirement, the overall REE recovery reached 95% with the addition of 240 g/L NaCl. Other reagents such as KCl, NH4Cl also showed significant enhanced REE recovery at the same oxalic acid addition. The addition of sodium sulphate appeared to largely enhance the precipitation of LREE but inhibited the formation of HREE oxalate. All results indicate the formation of rare earth double salts may play an important role in REE DOP sulphate media.INTRODUCTIONThe conventional routes for recovering rare earth elements (REEs) from a sulphuric acid pregnant leaching solution (PLS) involves an initial purification step for removal of iron, aluminium for example by precipitation through neutralization, followed by precipitation of REEs as hydroxide, oxalate or carbonate salts, or by bulk solvent extraction for REE recovery (Xia, 2013). Another route was used by Bayan Obo in their historical flowsheet, where the PLS was first subjected to double sulphate precipitation, then the remaining REEs, mostly heavy rare earth elements (HREE), were recovered by oxalate precipitation (Li, 2011)."

Jan 1, 2016

Of the many organic impurities present in Bayer liquor, sodium oxalate is known to have one of the most detrimental effects on the Bayer process. Because of its limited solubility, it will co-precipitate with gibbsite during the precipitation stage which results in many operational challenges for the refinery. Despite the importance of this phenomenon, the interaction mechanism between gibbsite and sodium oxalate is not well understood. In this study, the growth of sodium oxalate on three main morphologies (random agglomerates, prims and hexagons) of water-washed and caustic-washed gibbsite was observed under synthetic Bayer conditions using in situ optical microscopy. After a short induction period, oxalate started to nucleate on gibbsite crystals, and grew with a needle-shaped morphology which eventually developed into oxalate bundles. In addition, the results indicated that caustic washing was able to partly decompose gibbsite crystals and thus make the gibbsite surface rougher, which provides more potential sites for oxalate nucleation and growth. The growth rate of oxalate crystals on the basal (001) face of water-washed gibbsite was 1.33 µm/min determined by the time-lapse imaging of in situ optical microscope.

Jan 1, 2014

By Patrick Laflamme, Jean-François Boulanger

Les minerais de cuivre sulfurés, qui représentent 80% de la production mondiale de cuivre, imposent une étape de concentration des minéraux, premièrement pour atteindre une teneur en cuivre minimale qui permette le traitement pyrométallurgique, mais aussi pour limiter la présence d’élément pénalisants (délétères). Cette introduction offre un survol des principes, limites et pistes d’améliorations touchant la concentration des minéraux de cuivre.

May 2, 2024

By J. Fujioka, Y. F. Gu, C. Cui, D. Ping, A. Sato, H. Harada

"A new kind of cast & wrought (C&W) Ni-Co base superalloys named as ""TMW alloys"" are developed recently for compressor or turbine disks of gas turbine engines in High Temperature Materials 21 Project at National Institute for Materials Science (NIMS) in Japan. These Ni-Co base superalloys combine the characters of two kinds of y- y' two-phase alloys (Ni-base and Co-18at%Ti alloys) and have higher tensile strength and creep resistance than C&W UNDIMET 720Li superalloy."

Jan 1, 2006

By Jean Robitaille

La découverte du gisement du puits Penna a nécessité une révision complète de tous les circuits du concentrateur Laronde pour permettre, premièrement, l?adaptation du procédé à la nouvelle minéralogie et deuxièmement, l'accroissement du tonnage de 1800* à 4500 t/j. Aux circuits existants de broyage, de flottation du cuivre, de cyanuration et du charbon en pulpe, les circuits suivants furent greffés : broyage semi-autogène, flottation du zinc, manutention des concentrés (épaississage, filtration, entreposage et chargement automatisé), décantation à contrecourant et précipitation au zinc, destruction des cyanures et remblai en pâte. Cet article se veut une revue des différentes étapes du projet d'agrandissement du concentrateur qui se sont effectuées par phases progressives de 1997 à 2000. De plus, une description des nouvelles technologies sélectionnées et implantées est présentée.

May 1, 2001

By Ron H. Derammelaere

Coal Slurry Test Pipeline and First Recorded Commercial Pipeline Wallace Andrews founder of New York Steam Company awarded patent for ?Method of Transportation? that involved pumping finely divided coal in slurry form built test facility at Madison Avenue and East 58th Street in New York City died in 1899 in a fire and coal pipeline work was not continued First recorded commercial coal slurry pipeline designed by Gilbert Bell in 1914 to move coal from barges on the Thames River in London to a powerhouse in 8? tubes (660 yards long)

May 1, 2013

By D. Beneteau, L. Feldman, D. Milne, A. Hyett, G. Snell

"Behaviour of rebar bolts subjected to combined shear and bending in underground potash mining applications is not well understood. An experimental investigation compared load applied to resin-grouted No. 25 metric rebar to theoretical load, calculated using elastic bending theory. Distributed optical sensing (fibre optic) technology allowed axial strain measurements at 1.25 mm increments along the length of rebar. Experimental procedure, data processing methods, and equipment improvements are needed for field applications of optical sensing technology. Goals were to adopt procedures for instrumenting rebar bolts, conduct tests, and develop data interpretation methods to measure field deformations and loads. ¦ KEYWORDS Fibre optic, Potash mine, Rebar bolts, Transverse load testing RÉSUMÉ On appréhende encore mal le comportement des boulons d’ancrage pour barres d’armature soumis au cisaillement et au cintrage pour un usage dans des mines de potasse souterraines. Une étude expérimentale compare la charge appliquée aux barres d’armature de diamètre n° 25 (25 mm en mesure métrique) enduites de résine époxy à la charge théorique, calculée à l’aide de la théorie de la flexion élastique. La technologie de détection optique distribuée (fibre optique) a permis d’effectuer des mesures de la contrainte axiale à des différentielles de 1,25 mm sur toute la longueur de la barre d’armature. Pour des applications sur le terrain de la technologie de détection optique, il faut envisager une procédure expérimentale, des méthodes de traitement de données et une amélioration de l’équipement. Les objectifs établis consistent à adopter des procédures d’instrumentation des boulons d’ancrage pour barres d’armature, à effectuer des essais et à mettre au point des méthodes d’interprétation des données pour mesurer les déformations et les charges sur le site. ¦ MOTS CLÉS boulons d’ancrage pour barres d’armature, essai par charge transversale, fibre optique, mine de potasseINTRODUCTION Resin grouted rebar bolts are commonly used in potash mines in the province of Saskatchewan, Canada, in areas where shear deformation is observed in the rock, or where potentially unstable ground is present, including locations such as clay seams. Opportunities to observe deformations of rebar, as shown in Figure 1, are rare because it is unusual in underground potash mining to excavate supported ground. In this situation, a block of potash containing a rebar bolt had failed."

Jan 1, 2019

By P. Burke, V. Vuaroqueaux, A. Doyle, C. Petit, Kipouros. G. J.

Magnesium and its alloys are attractive for use in automotive and aerospace applications because of their low density and good mechanical properties. However, difficulty in forming magnesium and the limited number of available commercial alloys limit their use. The present work reviews the efforts to improve the attractiveness of magnesium through non-traditional processing, and presents results of current work on producing magnesium alloys via powder metallurgy (P/M). P/M can be used to alleviate the formability problem through near-net-shape processing, and also allows unique chemical compositions that can lead to new alloys with novel properties. The surface layer formed on the Mg powders during processing acts as a barrier to diffusion and sintering is problematic. The layer contains oxides, hydroxides and carbonates of magnesium, formed by reactions with the atmosphere. There are several means to possibly overcome this barrier. Alloying additions have been identified that may promote surface layer disruption during sintering. Processing variables such as sintering atmosphere may reduce the layer or allow the formation of less detrimental compounds. Post-sintering processes such as hot working may disrupt the layer and improve density. The experimental effect of all these processing parameters is presented in this paper.

Jan 1, 2010

By T. M. Korzekwa, R. L. Cavanagh

Following considerable experience with the beneficiation of Wabana iron ore by standard methods, a study was made of the benefits to be obtained by semi-reduction. The basis of the laboratory program was an extensive mineralogical and liberation investigation which guided subsequent work. Partial reduction and beneficiation on a laboratory scale was carried out on lump ore and fines. The reduced ore was magnetically concentrated and the concentrated fines were briquetted. Data are presented on reducibility, sizing vs reduction rate, magnetic cobbing and separation, and the elimination of phosphorus. Past work is reviewed briefly and comments are made on the relation of laboratory to pilot-scale tests.

Jan 1, 1967

By T. Hofbauer, M. J. Dry, G. B. Harris, C. W. White

"Urban Mining is a term that is increasingly being used, and represents an appreciable source of secondary materials for the metals extraction industry, a source that does not incur mining costs, but does, at present, incur considerable disposal costs. Electric Arc Furnace Dust (EAFD) is probably the most common of these materials, with an estimated global production of 8 million tonnes annually, of which 1 million tonnes is generated in North America. The contained annual metal value in EAFD at current prices is of the order of $6 billion, yet, apart from the zinc, virtually none of this is recovered.Despite many attempts over the years, with pyrometallurgical, hydrometallurgical or hybrid processes, currently the only commercially viable method of treating these materials is smelting in a Waelz Kiln (or a Rotary Hearth Furnace), which essentially recovers only the zinc, in an impure oxide form, and generates a secondary slag waste, which is still toxic and requires disposal. This paper describes the development of a chloride-based treatment process to recover all components of the EAFD in a marketable form, which centres around the novel hydrochloric acid recovery and recycle operation. Laboratory, miniplant and pilot plant data are presented, leading to the definition of a viable process flowsheet enabling the recovery of pure iron and zinc products (the principal components of EAFD), together with secondary products such as copper, silver, lead, cadmium, magnesium and manganese. A rigorous mass-energy balance is used to examine the preliminary economics involved."

Jan 1, 2014

By A. R. Sorta, D. C. Sego

ABSTRACT Temperature, solute, texture, and thixotropic effects on time domain reflectometry (TDR) measurements of water content in oil sands tailings are investigated. Results indicate that TDR water content measurements are influenced by temperature, residual bitumen, and percent clay in the tailings. A correction of 0.03–0.10/ °C must be applied to the apparent dielectric constant (Ka) to account for the effect of temperature. The Ka-volumetric water content relationships of slurries differ significantly from the commonly used Topp calibration equation. The age of the tailings and the addition of phosphogypsum did not influence TDR water content measurements.

Jan 1, 2013

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 F. Parada, R. Parra

"The neutralization process of SO2 from coal burning plants is a well-defined technology using limestone to form CaSO4 according to the following reaction: CaCO3 + SO2(g) + 1/2O2(g) = CaSO4 This paper presents the results of a study carried out to validate the option of capturing SO2 using gases from a non-ferrous smelter; SO2 content was up to 12% using a three-stage fluidized bed reactor. The difference in SO2 content affects equilibrium conditions and kinetics, rendering a direct extrapolation of the high efficiency achieved for low SO2 content impossible. The R&D program consisted of a laboratory study using a semi-pilot operation of a one-stage fluidized bed reactor and the construction and operation of a three-step reactor prototype. Results show that the reaction proceeds according to the unreacted core model that imposes a compromise between CaCO3 conversion and SO2 capture. For high SO2 capture, the calcine from the reactor contained CaSO4 and CaO. A complete capture of SO2 from gases with 8 vol.% can be achieved with a mean reaction time of two hours at 800°C."

Jan 1, 2007

By Mike Fontaine

The success of a project is defined by meeting the financial performance objectives of the business case within a stipulated timeframe. Early in design, little information is normally available; the uncertainty introduces risk to the project outcome. Using a range of risk management tools and techniques, a project can be developed from front end loading phases 1 through 3 (FEL1–FEL3), and project implementation (FEL4) and then into operations with an optimized probability of success. For every project element, the risk management framework embodies: establishing a context; assessing risk (identify, analyze, and evaluate); and treating risk. Embedded within design activities, this process mitigates or eliminates risks. Monitoring and control, as well as extensive communication and consultation with stakeholders, is integral to the risk management process.

Jan 1, 2015

By H. J. H. Pieterse

Agitation requirements in oxidation autoclaves can vary widely depending on the mineralogy of the feed material and the specific process selected. Before selecting an agitation system it is important that the client specify the desired throughput, mineralogy, chemistry, kinetics, compartments, overall retention time, and the desired oxygen utilization. In selecting the agitation system, the factors mentioned above as well as oxygen solubility, oxygen mass transfer coefficients, and specific power are evaluated. Much research effort has been directed toward open tank systems for fermentation and oxidation processes. However, for high pressure autoclave oxidation processes little information is available. In this review the author's experience in the autoclave industry and some of the available literature are utilized to compare the installed power per unit volume with some of the methods proposed for open tank oxidation. Equations that appear to give results close to that experienced in the industry have been identified. Further work is required in this area to develop a higher degree of confidence in the ability to predict the power required for any given case.

Jan 1, 2004

By L. C. Graton

Introduction The Porcupine district of northern Ontario has yielded over $300,000,000 in gold during its twenty-three years of mining operations. It thus ranks among the foremost gold producing areas of the world. Of this $300,000,000 already produced from the District, the Hollinger mine has furnished over 60 per cent and stands as one of the greatest gold mines of all time. In 1929, the Hollinger Directors decided to supplement the current geological and development work by an intensive investigation of the geology of the mine. This special study, begun in June of that year, was completed in October, 1932. An account of the geology of the mine in a degree of detail commensurate with the intensity of the study is in course of preparation. But the widespread interest manifested at the present day in gold occurrence generally, in Canadian gold deposits, and in the specific results of the investigation at Hollinger, appears to justify the immediate presentation of a highly abridged summary of our principal findings, insofar as they relate to the more general and scientific phases of the geological situation. Those conclusions having direct bearing on operating and exploratory policy are not dealt with here. The present preliminary paper, therefore, records chiefly the conclusions reached, with little incorporation of supporting argument or evidence. While intended to give a reasonably balanced perspective of Hollinger geology, the condensed presentation naturally emphasizes those views which are not in complete accord with accounts hitherto published regarding this district.

Jan 1, 1933

By R. Bruce Graham

"For the purpose of this paper, the Chibougamau area is taken as lying between lats. 49°20’ and 50°10’ N;-longs. 73°45’ and 75°30’ W. It comprises an area of some 4,000 square miles and is centred 300 miles north of Montreal.The first recorded report of metal deposits in Chibougamau was that of James Richardson in 1870-71 (I). In 1903 discoveries of asbestos, copper, iron, and gold made by Peter McKenzie stimulated considerable activity in the district. By 1909 interest had become so marked that considerable pressure was brought to bear on the Quebec Government to build a rail-way into the region. It was finally decided to have an authoritative opinion on its economic possibilities, and the Chibougamau Commission was appointed for this purpose (2). They examined the district in 1910 and concluded that at that time a railway was not warranted. Nevertheless, the district continued to be prospected and from time to· time gold and copper discoveries were made. Thus the Merrill Island deposit was discovered in 1920, the Campbell Chibougamau Cedar Bay deposit in 1922, Obalski in 1928, Opemiska Copper in 1929, and Norbeau in 1930.Difficulty of transportation was a severe detriment to the development of the region. Consequently the Quebec Department of Mines completed a road into Chibougamau in 1949. Further activity was encouraged. The Chibougamau Explorers, Quebec Chibougamau Goldfields, and Kayrand deposits were found in 1950. ** The copper-siderite zones on Copper Cliff ground were found in 1952 and 1953. Opemiska Copper, Campbell Chibougamau Mines, and Chibougamau Explorers were encouraged to prepare for production following favourable exploration results."

Jan 1, 1949