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By Jodi Wilding, Barry Lurnsden

The implementation of new technology to mineral separation operations requires rigorous testing to confirm the technology&apos;s technical and economic benefit. The Jaguar Mine owned by Jabiru Metals is located in Western Australia and sequentially separates a copper concentrate and then a zinc concentrate. Fine grinding (80% of zinc in tail is <25µm) is required to achieve efficient mineral separation. All mineral losses are therefore fine mineral losses, and so improvements in metal recovery must focus on this fine mineral. Magnetic aggregation technology has been shown to increase the recovery of fine paramagnetic minerals so it was an appropriate technology to evaluate at Jaguar. Testwork commenced in the copper circuit and it was found that there was a substantial reduction in copper in copper tail and an increase in zinc recovery to the zinc concentrate. The increase in zinc recovery in the latter zinc circuit was an interesting result and initiated the second stage of testwork that was to install and test a second magnetic conditioning unit in the zinc círcuit. This showed a further increase in zinc recovery. Magnetic conditioning technology has now been fully evaluated in the plant and is now part of the Jaguar flowsheet.

Jan 1, 2011

Microseismic (MS) methods offer one of the few ways to monitor a 3D volume of rock and essentially see into the rockmass and the regions of real time rock fracture. This is a critical component when considering workplace safety as well as the economic viability of a mining operation. New Gold Inc. New Afton Mine, an intermediate copper-gold mining company located 350km northeast of Vancouver in the south-central interior of British Columbia, Canada, has recently installed a MS system to help understand the block caving process in space and time. For a block cave mining operation is it important to utilize the MS events to map out the seismogenic zone related to the regions of stress concentration and fracturing mechanisms which lead to caving. The geological setting within the local array is complex, consisting of several distinct lithologies with unique material properties that each affect the microseismic signal differently. The block cave consists of a muck filled void, also affecting the seismic waveform path. This paper compares the use of a single velocity model to a variable velocity model which accounts for the differing lithologies and cave. The variable velocity method determined 3D raypaths for all source to receiver possibilities through five irregular shaped geological domains and the estimated cave. For calibration blast data, the variable velocity model is found to successfully decrease the error for event location from an average of 38m to 20m (47% improvement), and its importance to location accuracy is expected to increase as the cave develops in size.

Aug 1, 2013

By B. Yamamoto, D. Post, J. De Leon, A. Meike

"This paper describes the theory, design, building, and testing of the passive magnetic bearing stabilizing system which is the core of the passive magnetic bearing system. The stabilizing system is made up of two large magnetic disks opposing themselves with a stabilizing disk in the center which allows the system to self-locate in a null position without the need for external power sources or sensors. When outside forces act upon the stabilizer, the magnetic fields interact with the stabilizing plate to return the system to its null position. Collaboration between two industry leaders has allowed an actual prototype to be built and tested providing real data to prove out the theory.INTRODUCTIONMagnetic bearing/stabilizer systems have many advantages over conventional mechanical bearing systems. These include near-zero drag losses and no need for lubrication since the rotating elements make no mechanical contact with the stationary elements of the bearing system. However all magnetic bearing systems must contend with a constraint known as Earnshaw’s Theorem in the early 1800’s, this theorem asserts the impossibility of constructing a stable, non-contacting, electrostatic or magnetostatic levitation system using only fixed charges or fixed magnetic poles, such as those produced by permanent magnets. Because of the constraint imposed by Earnshaw’s Theorem virtually all present-day commercial magnetic bearing systems are of the “active” type. That is, they employ electromagnets that are powered by amplifiers the inputs to which come from sensors embedded in the bearing system. These sensors are a part of a feedback loop that operates to keep the levitated rotating parts of the bearing stable and centered. The resulting complexity means that active magnetic bearings are expensive, require periodic maintenance, and continuously consume electrical power to energize their amplifiers and their electromagnets.Passive magnetic bearings are, of course, also subject to the constraints imposed by Earnshaw’s Theorem but they solve this problem in a straightforward and simple way, with only “passive” elements that take advantage of a loophole implicit in the derivation of Earnshaw’s Theorem. This loophole is that Earnshaw’s Theorem as derived applies only to static systems, i.e. an assembly of stationary permanent magnets arranged so as to levitate an object containing other permanent magnets. The theorem can be overcome if dynamic effects are taken into account. In active magnetic bearings the “dynamic effects” involve the afore-mentioned sensors, amplifiers, and electromagnets."

Jan 1, 2012

The steam-filtration process for dewatering solids involves the application of slightly superheated steam to a filter cake during filtration. The mechanism by which the technique promotes water removal has been deduced from bench-scale experiments on coal and on granular iron ore concentrates. The mechanism, along with some of the applications and limitations of the process, is presented. Introduction I N the steam-filtration process, slightly super-heated steam is applied to the filter cake during filtration to remove more water than can be extracted by conventional filtration. Although this process was developed by Burton for coal filtration (1), it should have far wider applicability; certainly, it could be used to treat any mineral product, because only low-temperature steam is needed and most conventional filtration equipment can be easily adapted to it. As few restrictions apply to this process, however, it is important that its more obvious advantages and disadvantages be appreciated and, especially, that the criteria on which economic evaluations can be based are understood.

Jan 1, 1965

"Increasing demand for timely and accurate information about flotation plant performance requires metal accountants to increase the scope and reporting frequency of plant production. This trend has brought in-process inventory estimation at the forefront of metal accounting issues. Such significant in-process inventories can be locked in diverse process equipment (bins, holding tanks, flotation cells, thickeners, pipeline, etc.) or in stockpiles (ore, concentrates, tailings, etc.). Practice has shown that boldly ignoring these in-process inventories or the errors associated with their estimation lead to unreliable metal balances thereby creating confusion in plant production planning and operational performance assessment. To this extent, the characteristics (physical bounds, spatial heterogeneity and residence time) as well as the available measurements (volume, density, humidity, mass, composition, etc.) of each unit/section found in a generic flotation plant are jointly reviewed with respect to the particular metal accounting issues they present. The daily and monthly metal accounting tasks are then reviewed together with possible methods for obtaining reliable inventory estimates including different procedures for end-of month reconciliation.INTRODUCTION Most of the cost reduction initiatives of the mining industry aim at improving capital efficiency and asset utilization. Among the possible paths through which these goals can be achieved are mine-to-metal optimization, real-time plantwide process control (Hodouin, 2011) and knowledge sharing databases (Bascur & Linares, 2006). However, the successful implementation and subsequent monitoring will ineluctably results in an increased demand for timely and accurate information. This more than often requires metal accountants to increase the scope and reporting frequency of plant metal production. A striking example of such scope expansion is the Minas-Rio iron ore project in Brazil (Anglo American, 2013) having a pipeline route of 525 km between the concentrator and the concentrate shipping area. Several other mining companies have also set an increased frequency for their key performance indicators thereby shrinking the metal accounting period from monthly to weekly and daily. Those concurrent trends have brought in-process inventory estimation at the forefront of metal accounting issues. Indeed, as illustrated in Figure 1, improving trading reactivity requires improvements in production planning which strongly impacts the requirements for reliable metallurgical accounting. Furthermore, practice has shown that boldly ignoring significant in-process inventories or the errors associated with their estimation can lead to unreliable metal balances. In other words, since metal balances are the cornerstones of metal accounting, some of the risks associated with important business decisions are linked to errors associated with in-process inventory measurements."

Jan 1, 2014

By W. E. Kuhn

Introduction The work, of which some of the results are described in this paper, was started with the object of investigating the properties of certain binary alloys of titanium made from powders. Our main interest was in the possible use of such alloys in gas turbines. We were attracted to titanium, as have been others, by its high melting point (I,724° ± 11°C.), its low density (4.54), and the likelihood that, if a relatively wide use could be found for the metal, it might become available in commercial quantities at a fairly reasonable price. The readiness with which the metal reacts with hydrogen, oxygen, and nitrogen was recognized from the very beginning. At the same time there seemed a good chance that alloys could be produced which, because of the formation of protective films, would resist the attack of these and other corrosive agents. No specifications were drafted to cover the &apos;quality&apos; of the titanium hydride powder which was used in our work and which was, to judge by the results of a few preliminary experiments, the most useful source of titanium then (1944) available in sufficient amount for our purpose. During the course of our work, the need for such specifications became very clear (see Sections 9 to 12 of this pa per). Even today, lack of knowledge regarding the effects on titanium of impurities, some of which may later be looked upon as essential elements in commercial alloys of titanium, and difficulties in manufacture, make the preparation of specifications for commercial titanium and titanium compounds a doubtful procedure. The papers presented at the 1948 Symposium on Titanium, sponsored by the U.S. Office of Naval Research lend colour to this view. At the time our work was commenced, one had to depend upon the manufacturer to supply what he considered to be his &apos;best&apos; material. It may be some time before we can ask for more than this, the question as to what is his &apos;best&apos; being left to the manufacturer to decide. However, in this connection the results of our study may be of some value and on that account we are constrained to publish them.

Jan 1, 1950

By Frédéric Flament, Luc Lachance

"The important task of metallurgical accounting that used to be done manually is being more and more automated. Currently available solutions can generate accounting reports without human intervention or almost. However, the practical conditions for fully delivering the promised benefits of those solutions are sometimes overlooked either by end-users or by integrators. The mere fact of filling reports with values satisfying several constraints such as mass conservation constraints does not, by itself, ensure a high quality metallurgical balance. Since managers make decisions based on these reports, it is logical that the metallurgical balance performance be monitored and retrofits be made if necessary. Such retrofits may involve modifications to the measurement strategy or the reduction of the spatial resolution of the material balance model. This requires an estimability and redundancy analysis (ERA) tool to assess the feasibility of the modified model. Since determining by hand the estimability and redundancy of a set of non measured and measured variables is not trivial, even for a medium-sized mineral processing plant, a dedicated ERA tool brings valuable assistance to the metallurgist in charge. The present paper aims first at explaining how a state of the art metallurgical balance is a key enabler for the adoption of a smart process plants paradigm (SPPP) in mineral processing. Then, the fundamentals behind the building of an ERA algorithm are introduced and illustrated by two examples. Finally, the role of an ERA tool in achieving state of the art metallurgical accounting and how it contributes to delivering additional value are discussed.INTRODUCTIONThe Smart Process Plants Paradigm (SPPP)Mineral processors have seen an increase lately in external pressures toward operating performance improvements. Indeed, the globalization of the mining business is a key driver to becoming more productive, more responsive to market changes, to improving corporate governance and reporting standards. Furthermore, mineral processors are also expected by their neighbouring communities to continuously improve their sustainability score. These current pressures differ somewhat from the past ones in leading to a larger than ever number of conflicting constraints that plant managers must concurrently satisfy while maximizing plant profitability. It is in turn not surprising that this context requires actions involving more real-time collaborative actions between more people in more places than ever before."

Jan 1, 2011

In-Country Business Development Agenda ?Siting/Permitting/Operational Planning ?Securing, maintaining, enhancing social license to operate ?Biodiversity conservation and ecosystem services ?IFC Performance Standards ?Environmental, Social, Risk Governance (ESG) ?Climate change plan

Aug 1, 2013

By Antonius Prayoga

PT Smelting adopted the Mitsubishi Continuous Technology for its copper smelter plant which has been operating since 1998. Through a series of expansion projects, the plant annual production capacity increased gradually from 200,000 to 300,000 tons of copper. There were no significant modifications for the smelter to reach the 50% additional capacity. It was mostly achieved by intensifying the operation of the furnaces by increasing the oxygen content in the furnaces blowing air. Intensive smelting furnace operation caused shorter campaign life of some furnace refractory, especially the melt zone wall on furnace outlet. During each furnace relining, which is done once every two years, severe wall erosion was found. The worst condition occurred in 2007 when the smelting furnace experienced a melt leak through the eroded wall beneath the bath-line coolers. During the 2008 furnace relining, a modification was performed by installing vertical coolers behind the melt zone wall. Additional vertical coolers were installed during the 2012 furnace relining to extend the coverage area. The modification improved melt zone wall integrity significantly by keeping them safely within the two year campaign life. Recently a modeling study was done to estimate the influences of molten waves on furnace wall erosion. The aim of the study was to predict the impact of blowing parameters, such as blowing air velocity, on the melt wave character and wall erosion.

Jan 1, 2015

By M. Bélanger, H. -L. Jacob

"The province of Quebec has a strong tradition in industrial minerals. Ten commodities are produced and the annual total shipments have exceeded $600 million in recent years. Quebec is a world renowned producer of chrysotile, titanium slag, graphite, and ilmenite. Quebec is an important North American producer of mica, talc, and peat moss. This paper reviews the main minerals and commodities that have been the object of exploration or development in recent years, namely graphite, wollastonite, dolomite, and silica. Some of the leading projects concerning magnesium minerals and apatite-ilmenite are described. IntroductionQuebec has a strong tradition in industrial minerals. It goes back to the second half of the 19th century when the first graphite and apatite mines in the Gatineau area and asbestos mines in the Eastern Townships were opened. Since then, more than 25 commodities have been produced in Quebec, making industrial minerals an integral part of the Quebec mineral industry. Today, industrial minerals and building materials count for one third of the total mineral production in Quebec.Present industrial mineral production includes 10 commodities (Table 1). In the last five years, the value of industrial mineral shipments has varied between 500 and 700 millions dollars annually, which represents 20% to 25% of Quebec’s total mineral production. For many years, Quebec has been a major producer of chrysotile and titanium slag, the only producer in eastern North America of mica, graphite and ilmenite, and a leading Canadian producer of talc and peat moss. Quebec also produces, mainly for domestic markets, dolomite, limestone, salt and silica.Quebec’s industrial mineral sector has been quite active in the recent years. Exploration by government geologists and companies has led to the outlining of new deposits, some of which are now in production; others are currently being evaluated. Technical and economic studies are also underway to determine the feasibility of various development projects."

Jan 1, 1999

By Y. X. Li, L. R. Xiao, S. Gong, S. S. He

Porous copper and porous copper based alloys with controllable pore structure have been manufactured successfully by sintering evaporation process. This process consisted of mixing copper or copper based alloys with NaCl powders, hot pressing and final high-temperature sintering to evaporate the filler material of NaCl powders. NaCl was eliminated completely during vacuum sintering, and strong metallurgical bonding in the walls was achieved. The pores’ structural parameter (pore size, shape, and direction) and porosity can be controlled effectively. These porous copper and porous copper based alloys with controllable pore structure have great potential in many fields. Including heat dissipating materials, heat absorbing materials, chemical catalyst carriers, electromagnetic shielding materials, filtering materials, damping materials, silencing materials, battery electrode materials. INTRODUCTION The development of porous materials began in the 1960s. The research of activated carbon with high specific surface area made porous materials enter the stage of material research (Belyakov et al., 2008; Ferey et al., 2008). With the rapid development of science and technology, porous materials play an important role in material research, and gradually become an indispensable part of the material research field (Wu et al., 2012). The research of porous materials has gradually extended to metal, ceramics, plastics and glass and other fields. It has been successfully applied in many fields, such as functional materials, industrial production, aviation, medical materials, biochemistry and electronics, which fully shows that porous materials have considerable development prospects. Porous silicon, plastic porous materials and glass porous materials are the most widely used in the field of non-metallic porous materials (Capelle et al., 2012). Compared with non-metallic porous materials, metal porous materials have developed rapidly in the late 1980s and become new materials with good mechanical properties and excellent physical properties. Porous metal materials have many advantages, such as large specific surface, small specific gravity, good silencing effect, high stiffness, high electromagnetic shielding performance, good shock absorption performance, etc (Li et al., 1999; Ferey et al., 2008). Among its many applications, metal porous materials can be used as both functional materials and structural materials. In some cases, metal porous materials have dual functions and structures. It is a multi-purpose engineering material with excellent performance. At present, porous copper, porous aluminium and porous nickel are the most concerned materials (Chen et al., 2002; Yang et al., 2017; Liu et al., 2018). The preparation methods of porous copper and copper-based alloys mainly include self-propagating high temperature synthesis (SHS), capsule-free hot isostatic pressing (CF-HIP), spark plasma sintering (SPS) (Kvanin et al., 2008; Takahashi et al., 2008; Zhang et al., 2014). However, these methods can not accurately control pore structure parameters (including pore size, shape, orientation, distribution, etc.). In porous materials, pore structure plays an important role in the overall performance of materials. In order to control pore structure parameters accurately and optimize material performance, it is necessary to explore and develop new preparation technology. In this paper, the sintering evaporation process (SEP) was introduced for the preparation of porous copper and copper-based alloys. The core process of the preparation method is hot pressing and evaporative desalination. Hot pressing can make the pore orientation consistent. Evaporative desalination can ensure the complete removal of NaCl in the form of vapor in a short time, thus eliminating the corrosion of residual NaCl on the matrix metal (Gong et al., 2011).

Jan 1, 2019

By Dennis E. Bell

"This paper describes exploration and development to 1982 in the southern half of the northeastern British Columbia (Peace River or Northeast Block) inner foothills metallurgical coal belt. Gates Formation, Fort St. John Group, is the primary target; Gething Formation, Bullhead Group, is secondary. This part of the belt remains wilderness when compared to its other parts. Practical formational and structural mapping is described. A local problem known as the Secus Mountain or Mount Belcourt conglomerates is discussed. The three major explorers have been Denison Mines, PetroCanada, and Crows Nest Resources, all with partners. Initial mine construction and rail spur construction are continuing. The new town of Tumbler Ridge is being built. Introduction This paper describes exploration and development to 1982 in the southern half of the northeast British Columbia metallurgical coal belt. The area (Fig. 1) trends 120 km northwest from the Alberta border to the Wolverine River and Bullmoose Creek. The belt averages 15 km in width, and is 20 km at its widest. Physiographically, the area is dominated by rugged inner foothills, with relief to 1,500 m. The trend of the structures is transected by a dozen rivers flowing southwest to northeast away from the Continental Divide. The Rockies, lying immediately to the west, control the climate. One fact continues to colour all coal work in the area. When compared to the other parts of the western Canadian foothills and Rockies coking belt, it remains the least accessible and least mapped portion. Lack of access also makes all work expensive. Current activity centres about two mines in construction at the northwestern end of the area. Denison Mines and partners are developing their Quintette project, and Teck Corporation and partners are developing their Bullmoose project. PetroCanada and partners have intensively explored their Monkman-Duke Mounta,in project, but mine construction awaits better economic times. The rest of the area remains lightly explored, with the exception of some intensive work on particular structures by Denison and Petro-Canada. The focus of coal work has been metallurgical bituminous coal seams contained primarily in the Gates Formation (Fig. 2) and secondarily in the Gething Formation. These formations are found in generally en-echelon structures ranging to several kilometres in width."

Jan 1, 1985

By L. Kilburn

A survey of 281 mineral exploration agreements examines the ratios among three ways that may be used to purchase an interest in a mineral property, viz: pay cash, pay shams and make future expenditures on the property. The dollar value of the future expenditures exceeds that of cash or shams by about nine times in most of the 110 agreements that contain cash-expenditure or share-expenditure components. Results suggest that cash and shams are treated about the same in terms of value. Buyers and sellers haw opposing priorities for the way that they prefer to purchase a mineral property. These opposing priorities should give rise to a perceived 50:50 balance between cash/share payment and future expenditures to satisfy the idealized situation described by most definitions of fair market value (FMV). This balance between cash/share payments and future expenditures appears to be rationalized in negotiations to a FMV when expenditures are nine times greater than cash and/or payments. On this basis, it is proposed that the FMV of a property may be determined by aggregating the dollar amount of the cash/share payments plus one-ninth the dollar value of future expenditures, as set forth in the respective purchase agreement, and proportionately applying such aggregate to full property value.

Nov 1, 2005

By L. Kilburn

"A survey of 281 mineral exploration agreements examines the ratios among three ways that may be used to purchase an interest in a mineral property, viz: pay cash, pay shares and make future expenditures on the property.The dollar value of the future expenditures exceeds that of cash or shares by about nine times in most of the 110 agreements that contain cash-expenditure or share-expenditure components. Results suggest that cash and shares are treated about the same in terms of value.Buyers and sellers have opposing priorities for the way that they prefer to purchase a mineral property. These opposing priorities should give rise to a perceived 50:50 balance between cash/share payment and future expenditures to satisfy the idealized situation described by most definitions of fair market value (FMV). This balance between cash/share payments and future expenditures appears to be rationalized in negotiations to a FMV when expenditures are nine times greater than cash and/or payments.On this basis, it is proposed that the FMV of a property may be determined by aggregating the dollar amount of the cash/share payments plus one-ninth the dollar value of future expenditures, as set forth in the respective purchase agreement, and proportionately applying such aggregate to full property value."

Jan 1, 2005

By H. Nejati

Experimentally, the Semi-Circular Bending Moment (SCB) fracture toughness test results of Basalt Specimens Under Illumination (BSUI) have shown reduction in fracture toughness and failure force as a result of micro-cracking. The fractographic investigation of BSUI confirms initiation and extension of micro-cracks. Determination of a relation between strength reduction (herein fracture toughness reduction) and density, location and orientation of thermo-mechanical induced cracks due to microwave radiation is critically important. Numerical modeling can bridge strength reduction and the density of thermal microcracks generated due to microwave radiation. Discrete Element Modeling (DEM) is a power tool for simulation of micro-crack initiation, coalescence into macroscopic fractures and failure mechanisms in brittle rock specimens under different stress regimes (herein combination of pure tensile stress due to SCB testing, and thermal stress due to microwave radiation). For this purpose, a DEM modeling of SCB testing of basalt using EDEM (i.e., a DEM based software). DEM models are calibrated according to results of experimental SCB testing as reported in previous papers. This paper first reviews some background data on SCB fracture toughness, and experimental results of fracture toughness of microwave treated SCBs. Then it proposes a new methodology for simulation and validation of rock samples exposed to microwave illumination with regard to experimental results, and discusses the correlation between fracture toughness of BSUIs and density of micro-cracks, which is attributed to applied microwave power and duration of illumination.

Aug 1, 2013

By H. Hamza

Efficient and effective management of extraction process tailings is an essential ingredient for the continued success and development of Alberta&apos;s vast oil sands resources. Open-pit oil sands operations north of Fort McMurray recover bitumen from flotation circuits. Process tailings are managed in carefully engineered and monitored external tailings management facilities and in below-grade mine pits. In order to support reduction of production costs and improve upon established tailings management practices, CANMET has been working with the oil sands industry in a collaborative framework to assess the potential to integrate thickened tailings into oil sands extraction process flowsheets. Albian Sands has commercialized the process while others, including Syncrude Canada Ltd., continue to evaluate the suitability of the process for their operations. This paper provides an update on R&D work undertaken in recent years to assess and develop the potential of thickened tailings technology for the open-pit oil sands operators of northern Alberta. The aim of this work was to explore opportunities to optimize process efficiency and environmental sustainability by improving water and energy conservation and develop more alternatives for tailings management and reclamation.

Jan 1, 2004

By A. Trusiak

"Increasing energy costs in mineral processing is making it necessary for tighter controls over various parts of the concentrating process. Continuous monitoring and control of critical process streams can be easily performed by today's many computer systems. Indeed, the list of successful applications of computers to grinding and flotation control continues to grow. The day is rapidly approaching when the use of computers within concentrators for either process control or simply metallurgical accounting will no longer be a luxury, but a necessity. The benefits from such applications far out weight the initial investment.This paper describes the current application of a process control system at Brunswick Mining in north-eastern New Brunswick. Emphasis is placed on the control of a CuPb flotation circuit, and the benefits derived-from this control.No. 12 Cu-Pb Flotation: The complex nature of the Brunswick flotation process has been described else-where. 1,2,3 Four final concentrates are eventually produced, these being a Zn concentrate assaying 53% Zn, a 30% Pb concentrate, a 20% Cu concentrate, and a bulk Pb Zn concentrate assaying 35% Zn and 17% Pb. The Cu concentate, Pb concentrate, and bulk Pb Zn concentrate are all derived from a primary CuPb concentrate assaying 26% Pb, 11% Zn and 1.8% Cu.The No. 12 CuPb circuit produces approximately two thirds of the total primary CuPb concentrate. No. 12 ore, assaying 3.5% Pb, 9% Zn, 0.25% Cu and 100 g/tne silver, is ground in two parallel grinding circuits. Each line uses a 3.2 x 4.2 meter rod mill in closed circuit with two parallel 3.2 x 3.9 meter ball mills. Ball mill and rod mill discharges are classified in two stages of cycloning. The secondary cyclone overflow, or flotation feed, is controlled at 65% passing 37 microns."

Jan 1, 1981

By G. M. Brownell

Introduction Within the past year a new deposit of gypsum has been opened up and brought into production in the Province of Manitoba. Until 1930, Manitoba&apos;s entire production came from Gypsumville, northwest of Winnipeg, at mile 161 on the Gypsumville branch of the Canadian National railway. However, during 1930 a gypsum bed was opened up at a point one mile south of the village of Amaranth, forty miles north of Portage la Paririe, on the west side of lake Manitoba (See Figure 1). Although no exposure has yet been discovered, the presence of gypsum below the surface in that district has been known for many years as the result of drilling for water. In 1929, J. R. Spear (1), of Winnipeg, interested some local capital in the possibility of .finding commercial deposits of gypsum, and, after some exploration work in the area with a well drill, the Amaranth deposit was located. Sixteen holes were put down at intervals of 400 or 500 feet, all of which encountered what appeared to be a continuous bed of gypsum, about thirty-eight feet thick, at a depth of 92 feet. The extent of the deposit has not yet been determined.

Jan 1, 1931

By Stephen G. Hardcastle

Worldwide, metal mines are going deeper. For example in Canada there are six such mechanized mines planning production at 3000m (10,000?). Working at such depths challenges all aspects of mining including the provision of ventilation to supply an equitable working climate for personnel and machinery. This paper explores the overall challenges of supplying ventilation in Canada?s deepest mines and how the volumes required could be minimized. This is essential because it must be remembered that ventilation and refrigeration are not only costly items to supply, but the magnitude of their cost is also very sensitive to the volume supplied. For ventilation this is obvious because of the cubic relationship between volume and cost. In deep mines, the main function of ventilation is the removal of heat transferred from the strata and generated by the mining machinery, and the air volumes supplied are designed accordingly. The second consideration is the removal of other pollutants that could be harmful to humans such as diesel and explosive fumes. However, the need for ventilation at its present design levels could be reduced. This paper discusses the implications of such technologies as: teleremote mining and alternatives to diesel equipment on the magnitude of the volume supplied; ventilation-on-demand which recognizes ventilation as a costly and limited resource; plus other aspects, such as the benefits of controlled recirculation, local cooling, and heat rejection back to the strata to gain further advantage from new developments. Furthermore, this paper advances the need to be able to design ventilation systems more cost effectively and how such new advances as process simulators can be used in conjunction with ventilation simulators to explore the diverse options that could affect the air volumes required and provide more realistic economic data upon which to base design decisions.

May 1, 2003

By Lewis Finch

Oil and .gas reservoirs exist under pressure within the pore spaces of rock structures or traps. Wells are drilled to produce these reservoirs. Under primary operation, the natural energy of expanding fluids in and adjacent to the reservoir forces or drives oil and gas to the wells. There are three basic sources of energy: dissolved gas, water, and gas cap. Typical recovery by primary methods is only 10 to 25 per cent of the oil in place for the dissolved gas drive but is generally higher for the others. Secondary recovery involves the injection of water or gas to supplement natural energy, thereby increasing recovery over that obtainable by primary operation alone. In many cases ultimate recovery with secondary methods is 1.2 to 2.0 times the expected primary recovery. The type programme adaptable in a field depends on its &apos;primary performance and on certain reservoir characteristics. In the United States, application of secondary recovery methods is becoming increasingly important. About 22 per cent of United States oil production now comes from fields in which injection projects are operating. In 1953, nearly 1.4 million barrels of oil daily came from such fields, more than double the amount in the early 40&apos;s. Ultimate primary recovery from known pools is estimated at roughly 73 billion barrels. Secondary recovery projects already in operation will increase this to almost 80 billion, an increase of almost 10 per cent. Unitized secondary recovery projects have been very successful. From unitized projects alone, industry reserves of oil in the United States have been increased by 3 1/2 billion barrels. In Canada, secondary recovery has not been so wide spread mainly because D-3 reef reservoirs which have held the major reserves are under water drive. However, appreciable amounts of water are being injected in the Redwater D-3, Leduc D-2 and Joarcum Viking reservoirs, and gas in the Golden Spike D-3. In both countries, possible achievements in increased recovery through secondary recovery methods now in use and by new ones which may be developed through research and field trial are a challenge to the scientist and the industry.

Jan 1, 1956