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By W. J. Pearson

"""POTASH"" is a term applied to the compounds of the element potassium (K) and when used in agriculture and industry is ex-pressed in terms of potassium oxide (K2O), regardless of the actual com-position of the compound. When a chemical analysis is made of a fertilizer, the amount of K is deter-mined and then calculated to the equivalent amount of K2O. However, the compound K2O does not exist in nature. Most of the world's potash supply is derived from mineral deposits similar to those in Saskatchewan and New Mexico. However, there is some production from concentrated surface brines such as occur in Searles Lake, California; Salduro Marsh, Utah; the Dead Sea; and from well brines in Micl1igan."

Jan 1, 1960

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 J. W. Craig

CHROME ore, which is used in Canada in the production of ferro-alloys, in a variety of refractories, and indirectly in many chemical industries, is both commercially important and scientifically interesting. The sight of chromium metal is familiar to all of us in the home, the office, the automobile. Chromium is synonymous with armaments: it is understood to be one of several essential metals in tanks, which played an important role in the defeat of France in the spring of 1940. Chromium, in other forms, comes into our daily lives by way of paint and leather, of the familiar green ginger-ale and beer bottles, and more indirectly in every pound of steel produced in the .Dominion. Necessary to our civilization in peace and war, the ores of chromium occur in many corners of the earth. This paper attempts to describe the chemical constitution of chrome ores, their world distribution, and the various chrome products and their industrial applications in Canada.

Jan 1, 1940

By N. F. Faria, F. Monteiro, B. O. Taiwo, A. Palangio, D. Fonseca, J. Manuel

This paper explores the interpretation and application of Particle Size Distribution (PSD) curves in optimizing blast design and enhancing downstream operations. The study looks at important factors like D50, D80, fines content, and the uniformity index to show how PSD curves affect the efficiency of different mining processes. The first section of this paper discusses the impact of blast design parameters such as burden, spacing, and explosive energy on the resulting PSD, highlighting their significance for downstream operations like crushing, and material handling. The section concluded that proper alignment of PSD with downstream size classes, like primary crusher inlet sizes, among others, can result in substantial cost reductions and productivity gains. The second part presents a case study from dstgroup aggregate quarry in northern Portugal, utilizing fragmentation analysis to evaluate blast performance and promote continuous improvement. The section specifically examines the effect of stemming material size on blast fragmentation, comparing the impact of using aggregate with a D80 of 12.32 mm versus a D80 of 21.94 mm. The D80 value represents the particle size at which 80% of the stemming material is smaller, making it a critical parameter in evaluating the stemming's effectiveness in confining explosive energy. The drilling and blasting designs were meticulously planned using O-PitDev and O-PitSurface software to ensure accuracy in blast parameters and layout. To assess the fragmentation resulting from these different stemming material sizes, the study utilized WipFrag 4 software. The software allowed for precise measurement of particle size distribution after the blast, as well as a detailed comparison between the two stemming sizes. Results from the analysis indicate that using bigger-sized stemming material led to improved blast confinement, which in turn resulted in better fragmentation compared to the smaller-sized material. The reviewed blast videos demonstrate that the larger aggregate effectively contained the explosive energy within the borehole, thereby reducing premature venting and directing more energy towards breaking the surrounding rock mass. This led to finer fragmentation with D80 = 1240.1 mm, D50 = 685.9, and Dmax = 2580 mm, which is advantageous in downstream operations like crushing and milling. On the other hand, the smaller stemming material (D80 = 21.94 mm) did not confine the explosive energy as efficiently, resulting in coarser fragmentation (D80 = 1327.37 mm, D50 = 750.76, and Dmax = 2370 mm) and reduced overall blast efficiency. These findings highlight the significant influence of stemming material size on blast performance and fragmentation outcomes. 

May 4, 2025

By C. Van Den Heuvel, C. B. Van Buuren

BIOX® has been successfully demonstrated over the past 2 decades for the recovery of gold from refractory sulphide concentrates. To date 12 successful BIOX® plants have been installed in 8 countries spanning 4 continents with the 13th installation currently nearing completion in the Philippines. In 2010 BIOMIN introduced the ASTER™ process for improved water balances in commercial BIOX® applications by supporting tightening environmental legislation on water usage and availability in both arid and tropical regions. Previously, a common challenge for BIOX® plants was the inability to recycle thiocyanate containing water due to the low tolerance of the organisms. ASTER™, a biological thiocyanate and cyanide destruction process, renders a non-toxic solution for re-use in BIOX®. Two commercial ASTER™ plants are in operation with the 3rd ASTER™ plant under construction in the Philippines. A 3rd BIOMIN technology, specifically developed for double refractory ores is available for implementation. The HiTeCC process has shown considerable success on ores where competition from disseminated carbon has rendered ineffective gold recoveries. Through HiTeCC, gold is desorbed from the carbonaceous matter by manipulating the ionic strength and temperature of conventionally treated CIL product. One Australian commercial plant utilises HiTeCC while a 2nd installation is set for commissioning 4th Quarter 2014. BIOMIN’s premier solutions for refractory gold processing are described herein.

Jan 1, 2014

By K. Baris

Methane (CH4) present in coal seams, generally known as Coalbed Methane (CBM), Coal Mine Methane (CMM) or Coal Seam Gas (CSG), is a major energy source, as it is the primary constituent of natural gas. At the same time, released methane is a potent greenhouse gas (GHG) and a major safety hazard in underground mining operations. Therefore, a considerable effort has been undertaken to develop coal bed methane extraction and utilization technologies that can achieve both environmental and safety benefits. Countries with significant coal reserves and gassy seams, i.e., USA, Australia, Canada, China, India, Poland and Germany have developed mature methodologies and practices to extract, before and during mining, and utilize significant amounts of methane from coal seams. Nevertheless, on a global scale, methane recovery remains untested and many technical and economic challenges require urgent attention. The research presented in this paper, sponsored by the United States Environmental Protection Agency (EPA), is focused on the Zonguldak Basin, the only hard coal region in Turkey. The basin is known to contain very gassy coal seams and consists of three major regions: Armutcuk, Zonguldak and Amasra. Among the three, the Amasra coalfield is considered as the most favorable for CBM recovery, as it comprises of deeper coal seams and where a private company, Hema Enerji A.S. (Hema) is already developing coalbed methane production facilities. This study aims at developing a reservoir model to predict the potential CBM recovery from the CBM-2 well, the only producing CBM well drilled by HEMA Enerji A.S in the Amasra coalfield. History matching was utilized to model the 15-day production data and uncertainty analysis was performed to estimate the optimum values for the reservoir parameters. The produced model yielded an average production rate of 143 m3/day for 10 years. The total amount of CH4 to be produced during this period was 0.53 million m3. Furthermore, the total amount of GHG to be avoided was estimated at 6585 tCO2e.

Aug 1, 2013

"THE CONCEPT of energy as a commodity, while not entirely new, is not as widespread as the importance of the idea to this modern world would lead one to expect. The growth in the supply and use of energy over the past years has been tremendous, but our very closeness and familiarity have somewhat distorted the viewpoint, particularly of the younger generation. To many of us who remember the wonderful satisfaction of our first responsibility for directing two horsepower hitched to a farm cart or hay wagon, there still arises a feeling of some awe at the casual flick of the switch with which our sons and daughters summon to their convenience the service of some one hundred or more horsepower.Energy is the vital component of our existence and, no matter what contempt our day-to-day familiarity may •breed, it is wise to .pause from time to time and consider our national energy standing. Have we still capital in the bank? Are our expenditures wisely •conceived and well directed? Is provision being made for the years •ahead for the needs of our children and our children's children?"

Jan 1, 1953

By Y. Huang

Corrosion of GaAs in aqueous electrolytes is a major limitation in implementing GaAs-based photoelectrochemical solar energy conversion systems, In this work, the corrosion behavior was investigated by electrochemical methods and surface analysis approaches, in both H2SO4 and NH3?H2O solutions, Open-circuit measurements showed that the cleaned GaAs surface was very sensitive to water/air, Impedance measurements for n-GaAs showed that an inductive loop only appeared at a high corrosion rate because a reaction intermediate is the oxidant for a further decomposition step in combination with chemical reaction with water, The results suggest that the same corrosion/decomposition mechanism occurred on n-GaAs in the two solutions, When the surface-hole concentration was low, the hole injection or generation process was the rate-determining step, At large reverse bias on n-GaAs, with high-hole concentration, the corrosion rate was limited by a Faradaic adsorption process, involving an adsorbed intermediate, The different surface compositions after corrosion in the two solutions can be explained by the dissolution of As(0), Further oxidation of As(0) to As(III) in NH3?H2O solution is still slow, as suggested from X-ray photoelectron spectroscopy (XPS) analysis,

Jan 1, 2005

By William G. Pariseau

"This contribution describes linkage of stress concentration at the face of tabular excavations, for example, longwall coal mine panels, at a meter scale to surface subsidence at a kilometer scale. Joints are considered according to orientation and spacing at an intermediate scale. A new dual-node, dual-mesh technique based on first principles uses a multi-scale technique that allows for computing whole mine surface subsidence while also allowing for computational details of stress, strain and displacement about main entries and pillars, panel entries, and bleeder entries. The technique is implemented in a conventional continuous Galerkin finite element program that has been in use for many years.The advantage of the dual-node, dual-mesh technique is the capability to do a whole mine analysis that takes into account interaction between all sections of a mine where stress transfer over long distances is often the rule rather than the exception while at the same time allowing for details of stress concentration at working faces where caving is initiated and subsidence begins. The technique, outlined recently during ARMA 2014 (Pariseau, 2014), is applied to an underground coal mine in central Utah where mines are developed from outcrops in steep canyon walls. Meshes contain over 10 million, three-dimensional nodes; runtimes are typically overnight, as a practical matter. Results compare favorably with mine subsidence measurements made over a period of several years and show the capability of this new technique to provide useful design guidance for tabular deposits such as underground coal mines. The role of variability or uncertainty in strata properties is illustrated in element safety factor distributions about development, bleeder and main entries and pillars. Such details are new in this contribution. Energy tracking for mine-induced seismicity is also new. Results show a high correlation between number of events and failed elements and suggest a simple index to mine induced seismicity."

Jan 1, 2015

By Paul B. Warrington

This paper presents a discussion of the factors affecting copper scrap markets, including such items as price levels, freight. grades of material, sources and packaging. Reference will also be made to the effective life and turn-around of the copper content of some products. Introduction IN TERMS OF SIZE, copper scrap is second only to ferrous scrap in tonnage recycled. However, in total value, it is second to none. For example, world scrap recovery during the preceding 4 years averaged just under 2,300,000 metric tons per annum, and at an average price of 70 ¢ a pound, this works out at a turnover of about $3.5 billion, which indicates that the copper scrap industry, or recycling as it is now becoming known , is a substantial one.

Jan 1, 1977

By Charles Camsell

THE Northwest Territories covers a very large area-more than one-third of all Canada-and its most northern point, Cape Columbia in Ellesmere island, is distant only 500 miles from the Pole. Our first knowledge of the Arctic Archipelago, of which Ellesmere island forms a part, resulted from a gold-mining venture in Queen Elizabeth's reign. The English navigators of that time were eager to find a north-westerly and shorter and Jess hazardous route to the riches of China and Japan than that which Magellan had discovered, but they were unaware that the continent then known to bar a direct route extended in great width far to the north. Frobisher was one of these navigators. He reached in 1576 the bay in Baffin island now named after him, convinced that he had found a passage connecting the Atlantic with Asiatic seas. Forced to re-turn after ordeals in which ice, wind, and Eskimos flayed formidable parts, he brought back, among other novelties, a piece o black stone which had been picked up casually by one of his officers, and gave a little of it to the wife of one of the venturers, or financial backers of the enterprise. To quote now from Hakluyt: ? 'She by chance threw and burned it in the fire so long that , at length being taken forth and quenched in a little vinegar, it glistered with a bright marquesset of gold. Whereupon the matter being called in sorne question, it was brought to certain goldminers in London to make assay thereof, who indeed found it to hold gold and that very richly for the quantity." On the strength of this, the venturers, anticipating much profit, launched a second expedition to secure more of this stone, and 143 persons, including 14 miners and finers, set forth in 1577 and returned the same year, with, however, 200 tons of another mineral. Influenced by glowing accounts of veritable mountains of this mineral and by assays made after "additaments"-that is how "salting" in those days was described-the venturers, including Elizabeth, supplied funds for erecting a smelter and refinery at Dartford and outfitting a stilllarger expedition. And so, in 1578, fifteen ships departed with the Queen's blessing, for the same remote shores. After many mishaps, they returned with over 1,000 tons of the mineral, but when it yielded very little of value at the works in Dartford, the? Company of Venturers was forced into liquidation. Though our first prospector and miner was rather inconsiderate of the investors, he proved the existence of an archipelago, hitherto unknown, and secured much information about the new land and its dwellers.

Jan 1, 1938

By P. L. Li, B. X. Song, C. H. Wang, T. Wang, Z. Hu

"The treatment of an oxidized copper-gold ore by stage cyanide addition was investigated. For cyanidation, free cyanide ion concentration can be an indicator of whether there is copper dissolved in cyanide solution, and maintaining the free cyanide ion concentration lower than 1.0 g/L could be an effective way to prevent copper dissolution and reduce cyanide consumption. For that purpose, stage cyanide addition was introduced to control free cyanide ion concentration within the range from 0.8 to 1.0 g/L. Cyanidation tests results indicate that gold extraction was still acceptable at reduced cyanide consumption with a lower copper extraction. Based on the experimental study, industry application works at Beiya concentrator of Yunnan province, China were successfully conducted. When the raw ore contains 2.95 ppm Au and 0.75% Cu, by stage cyanide addition method, the gold extraction was still 93% at reduced cyanide consumption of 2135 g/t, which was only half of one addition method, and the copper extraction dropped to only 5%, which indicated that dissolution was prevented for almost 75% of the malachites.INTRODUCTIONCyanide with its competency to form a strong complex with gold, is the most preferable lixiviant for gold leaching. However, cyanidation is not inherently a selective process since many other minerals present in the ore are also readily soluble, especially the copper minerals. Muir (2011) reported that every 1% reactive copper present in the ore consumes about 30 kg/t NaCN, which can have detrimental effects on the process efficiency and economics due to high cyanide consumption, reduced gold leach rates and poor gold recovery."

Jan 1, 2016

By K. G. Baxter, D. G. Dixon

The Sepon process plant utilises an autoclave to oxidize a flotation concentrate containing pyrite, residual copper minerals, and sulphur. The concentrate is produced from the residue of a preceding atmospheric copper leaching circuit. The function of the autoclave is to provide iron and acid for that atmospheric copper leaching circuit. The key issues in the operation of the autoclave are to maximise the production of acid and ferric ions and to avoid scaling issues related to sulphur balling in the autoclave. Scale control in the autoclave was examined using various dispersants and residue recycle without success. Operation of the autoclave at high temperature and high acidity addressed the scale issue through rapid oxidation of the sulphur and produced a ferric sulphate precipitate in the residue that could be re-leached to provide ferric iron. This paper presents the development steps followed, through batch and continuous piloting that resulted in an autoclave circuit design that addressed the above process requirements. Following definition of the process design basis, modelling of the autoclave operation was carried out to assist with engineering design. The model included thermodynamics and kinetics of oxidation of pyrite, elemental sulphur and covellite and also considered gas/liquid mixing, oxygen solubility as a function of temperature and solution composition, ferrous to ferric oxidation, gangue reactions with acid and precipitation/re-dissolution of basic ferric sulphate and alunite.

Jan 1, 2004

By G. K. Quainoo

In the automotive industry, the awareness to meet Corporate Average Fuel Efficiency (CAFE) standards has evolved the need to reduce vehicular weight in new automobile designs, with the overall goal of reducing gas emissions into the atmosphere (Kyoto protocol), One efficient method has been to use lighter materials such as aluminum in outer body panels, Heat treatable AA6111 is one of the materials employed due to its unique combination of formability, paint bake strengthening and superior corrosion resistance characteristics, Researchers have applied various thermo-mechanical processes on 6000 series aluminum alloys and have found an improvement in the mechanical properties of these alloys, For a formed and painted automobile panel, the final mechanical properties involve a combination of strength components arising from cold work, strain aging and precipitation minus recovery. In this study, the evolution of microstructure resulting from the interaction of cold work and precipitation in AA6111 has been studied by means of transmission electron microscopy (TEM) after subjecting samples to various heat treatments, tensile testing and differential scanning calorimetry (DSC), This has been done to understand the evolution of microstructure and its influence on the properties of the alloy, The results show a considerable improvement in strength with a corresponding increase in strengthening precipitates with increasing level of cold work in the alloy. DSC results following the application of various levels of cold work also show acceleration in the precipitate phase formation, as precipitates are observed to form at lower temperatures, with increasing level of cold work/

Jan 1, 2005

By Gilles Tremblay

The legacy of orphaned/abandoned mines, with their associated environmental liability, human health concerns and the financial costs of clean up is a serious issue facing Canada. In 1999 and 2000, a number of stakeholders put forth requests to Mines Ministers to establish a joint industry-government working group, assisted by other stakeholders to review the issue of abandoned mines. The Ministers supported this initiative and asked that a multi-stakeholder workshop be organized to identify key issues and priorities. The Workshop on Abandoned Mines, held June 2001 in Winnipeg, developed consensus, guiding principles and recommendations that were presented at the Mines Ministers? Conference, September 2001. Ministers agreed on the importance of a large-scale program for the rehabilitation of orphaned/abandoned mines sites. A multi-stakeholder Orphaned/Abandoned (O/A) Mines Advisory Committee was formed and a plan was developed to study various issues relating to the implementation of remediation programs across Canada. Three task groups were formed to address the following key areas: Information Gathering; Community Involvement; and Barriers to Collaboration. The presentation will include a summary of the results of the three projects and the future work plan for the program.

Nov 1, 2002

By D. -A Tremblay

Dynamic wetting spread factors and interfacial heat transfer coefficients were determined for aluminum droplets solidifying on copper substrates, The spread factors were determined from the droplet geometries while the heat transfer coefficients were obtained by solving inverse heat conduction problems, 1-D and 2-D heat transfer models are presented and the results they provided are compared, For the latter, a sensitivity analysis was also performed to determine the influence of thermophysical properties and boundary conditions. Experiments were alternatively carried out with three different gaseous atmospheres and the dynamic wetting spread factors were correlated to the interfacial heat transfer coefficients.

Jan 1, 2005

By E. M. Timoshenko, A. V. Tarasov

The results of laboratory, bench-scale and semi-commercial investigations of a method for adding surfactant (technical-grade lignosulphonate) to the process of pressure leaching of nickel-containing pyrrhotite concentrates have been discussed. Lt has been demonstrated that feeding of technical-grade lignosulphonate distributed along the length of an autoclave ensures a reduction in its requirement by a factor of 1.5 to 2 as compared with single-point feeding; it also results in a decrease by 5% in the unit requirement of metallized iron-bearing precipitator in the process of non-ferrous metals precipitation and reduces by 0.05 to 0.1% (abs.) the nickel and copper contents in the tailings of the given process. Technical solutions have been proposed for commercial introduction of the process.

Jan 1, 2004

By E. LaRocque

Denison Mines Limited has been processing uranium ore in the Elliot Lake area for the past 20 years. As the original concept of uranium processing has been modified somewhat over this period, the present paper will describe the current recovery practices at the Denison mill from crushing through concentrate drying and packing . Special emphasis will be placed on the leaching, ion exchange and precipitation sections of the process, with consideration being given to the entire circuit. Descriptions will be given of equipment now being used and control strategies will be discussed.

Jan 1, 1979

By A. M. Bell

General Summary THIS paper attempts to describe in a preliminary and general manner the nature of certain copper discoveries now being developed by Gaspe Copper Mines, Limited, in Holland township, in the interior of the Gaspe peninsula. Some copper mineralization appears to have been known here at the time of the earliest French explorations, was rediscovered in 1921, and has been under intermittent development by Noranda Mines since 1938. In the last two years discoveries have enhanced the picture so that the deposit now promises to develop into one of the important Canadian copper producers. As ideas are constantly changing with continuing development, any picture given now is very partial and tentative and must be subject to future revision. The nature of these copper occurrences differs from others known in eastern America. In many respects they have unique features but they are most closely akin to some copper deposits found away from the intrusive rocks in the porphyry copper districts of the western United States. The most important orebodies are replacement deposits in a limestone horizon in which the ore gangue is converted to skarn. These lie at considerable distances from any known intrusive but seem to have been derived from a buried stock of granite that intrudes the sedimentary rocks of Lower Devonian age. This intrusive has produced alteration effects in the overlying rocks that may afford a key to locating other ore areas in the Peninsula.

Jan 1, 1951

By A. J. Naldrett

"Sulphurization of peridotite, that is 'to say reaction between sulphur from an external source and iron and nickel in the silicate minerals of the peridotite or in partially consolidated magma, is believed to be the me-chanism by which the small iron-nickel sulphide deposits associated with the ultrabasic rocks of the Porcupine district have formed.The pyrrhotite-pentlandite ore at the Alexo mine, Dundonald township, is localized by a shear that closely follows the lower contact of a peridotite lens. In the past, to account for this orebody, the magmatic segregation hypothesis has been advanced on the basis of textural evidence and the presence of the sulphides at the base of the lens. The nickel sulphide de-posits of the Porcupine, however, are not characteristically found along the basal contacts of bodies of peridotite. Furthermore, this study has shown that textures formerly thought indicative of magmatic segregation have been formed in certain deposits by the selective replacement of silicates by sulphides.At the Alexo mine, very minor amounts of pentlandite and heazle-woodite (Ni3S2) occur in the peridot-ite hanging wall adjacent to the ore. These sulphides are interpreted as having formed by sulphurization, the sulphur involved coming from the pyrrhotite-pentla.ndite ore emplaced along the shear. This reaction aureole raises the question of the role of sulphurization in the formation of the main mass of the sulphide ore. The very localized equilibrium that has been found to exist between sulphides and silicates in deposits throughout the area, the results of nineteen sulphur isotope determinations, and the abundance of pyrite and pyrrhotite in the volcanic country rocks of the Porcupine indicate that these deposits were formed by sulphurization rather than magmatic segregation."

Jan 1, 1966