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By Thomas C. Poulter

Abstract The Poulter seismic method of geophysical exploration is an attempt to obtain an increased efficiency in the conversion of the energy of an m~pl06ion into useful energy which has directive properties and which contains a minimum of random frequency and random phase relations. Very little effort has been made in the past to simplify OT even control the uniformity of the seismic energy being introduced into the ground. The Poulter seismic method is also an attempt to improve the signal-to-noise ratio not merely by trying to complete the impartial filtering done by the earth on ,the continuous spectrum of primarily high-frequency energy radiated from a shot point but by applying a frequency control at the point of origin of the seismic wave. The energy from a shot-hole charge is peaked in a frequency which is much higher than will be transmitted through the ground, and its absorption introduces background interference. Only 10 to 20 per cent of the seismic energy of a shot-hole charge .is directed downward in a 90-degree vertical cone, whereas, from a pattern of charges detonated above the surface of the ground, 85 per cent of the seismic energy is included in a 90-degree cone and in some cases it is even confined to as small as a 30-degree cone. This greatly reduces the horizontally distributed energy, thereby producing a marked improvement in the signal-to-noise ratio. The frequency of the signal energy may be peaked in a rather narrow range by the proper application of two or more impulses upon the surface of the ground controlled as to direction, magnitude, and timing. These impulses may be controlled by the reflection shock wave technique, the pressure pulse technique, and the sequence firing technique, using the primary controls as outlined. The information obtained from the study of directivity of seismic energy in a high velocity, uniform material such as the ice on Taku glacier, in the Juneau ice field in Alaska, has been of great assistance in the application of the method to oilfield and mining problems.

Jan 1, 1950

By L. P. Connolly, M. J. Fraser

"Hydraulic transport of solids has long been an important technique in mining and beneficiation. More recently, slurry pipelines have proved to be economic for longdistance overland transport of many commoditieis, including iron ore concentrates and coal. Now, the Marconaflo system brings the many advantages of hydraulic transport to bulk storage, loading, transportation and unloading of ships and other carrying equipment, thus providing important new means for delivering mineral commodities to market. In this paper, the authors describe the Marconaflo system and the potential economies which can be realized when applying it for loading, transporting, storing, reclaiming and blending a variety of mineral commodities, using several commercial installations as examples."

Jan 1, 1972

By Robert Maquil, Gilles Didier, Walter Steiner

"The 1580 m long dual-tube motorway tunnel Markusberg near Schengen, Luxembourg experiences strong swelling phenomena in each tube related to a 35 m wide diagonally crossing rock layer, some150 to 200m from the east portals. Overburden over the roadway is 26 to 30 meters. Tunnel construction started in 1998 and the tunnel was opened in 2003. The tunnel was driven downgrade from the West, the heave phenomenon started to occur as the tunnel approached completion. No indications of the presence of anhydrite and dissolved sulphates were known prior to tunnelling. Water samples had been taken from the beginning of construction and the concentration of anions and cat ions determined. Sulfate content was substantial, in one well it reached 22 mg/l, this high concentration requires the presence of other ions, in particular sodium and chlorine. Based on the knowledge at the time of construction heaving ground was removed from the tunnel invert and a free space was left below the roadway that is covered by a transversely spanned slab. In addition a series of posttensioned tiebacks were installed below the sidewalls. The void left in 2003 was 1.7m high and closed to less than 0.5 meters in 2007 then it became necessary to widen the free space. A central trench was dug with a height of about 2.5 meters and the benches were lowered.Level surveying had been carried out since 2002. In 2006 two extensometers were installed, one in the zone of strongest heave, the second at the edge of the swelling zone. The extensometer in the center of the swelling zone indicated heave with an essential constant rate with seasonal variations, the heave is concentrated in layer from 2 to 5 meters that heaved by nearly 300 millimeters within 5 years or 60 mm/year, which equals to approx. 1% extension per year. At the abutments heave rates of 20 mm/year where the support resistance is higher were observed. With data from other case histories a relation of heave rate with support resistance was established. Based on the numerous field observations hypotheses for the complex in-situ swelling processes, involving rock mechanics, mineralogical, soil mechanics and hydrogeological aspects were developed"

Jan 1, 2015

By Barry D. Simmons

Abstract -A well-defined approach is essential to ensure the long-term success of a regional exploration program. Teck's approach in eastern Canada is designed to fulfill corporate objectives while recognizing certain unique parameters for exploration in the area. The elements of this approach include clearly defined objectives, technical considerations and personnel policies, all of which are equally important. The goal is a significant discovery before the mid-1990s and the company is confident that this target will be achieved.

Jan 1, 1992

By R. Argane

In this work we assessed the geochemical behavior of concentrator tailings deposited at the abandoned mines of Zeida and Mibladen (Upper Moulouya, Morocco), using physico-chemical analyses, mineralogical characterization, acid base accounting and weathering cell tests. The aim of the study was to evaluate mine drainage quality and to assess metal mobility from these concentrator tailings. Chemical analyses show that the Upper-Moulouya abandoned tailings contain relatively high quantities of lead (0.261 to 0.594 % wt). Mineralogical analyses reveal the abundance of neutralizing minerals (calcite, dolomite, ankerite, and aluminosilicates) which influence mine drainage and metal mobility in mine tailings. Leachate analyses from weathering cell tests show alkaline conditions, small conductivity values, and low solubility of Pb-mineral phases. According to these results, abandoned mine tailings in the Upper-Moulouya district have very low potential for generation of contaminated mine drainage and for leaching of heavy metals. However, the inhalation of tailings exposed to winds generate dust problem facing the local population and may cause health consequences.

Aug 1, 2013

By C. Klinkenberg, G. Zhu, K. Hulka, S. V. Subramanian

A quantitative model based on strain accumulation in multi-pass rolling is developed to overcome a large critical strain for dynamic recrystallisation in a Nb microalloyed steel with high Mn content (HTP steel). The larger the critical strain for dynamic recrystallisation, the finer is the dynamically recrystallised grain size. The initial mill trial showed that it is feasible to achieve ultra-fine grain size by dynamic recrystallisation but the prevention of static recrystallisation in between passes is identified as an essential condition to suppress mixed grain size. The data-base on static softening kinetics at short interpass time was experimentally determined on WUMSI and incorporated in the model. The model is used to optimise the strip rolling schedule to prevent static recrystallisation in the interpass time. The rolling simulation of strip rolling schedule has validated the model prediction that it is possible to obtain a uniform ultra-fine ferrite grain size of about 1-2 micrometer diameter in final ferrite microstructure for industrial rolling parameters. A user friendly software package has been developed to apply the model for off-line control of mill processing parameters, i.e., time-temperature-deformation schedule of finish rolling in order to accumulate large strain to overcome a large critical strain for dynamic recrystallisation. The model is a powerful predictive tool for grain size control in multi-pass rolling.

Jan 1, 2004

By Sanjiv Dhanjal

"Often mineralogy dictates the physical properties of a material rather than chemistry. This in turn affects how that material behaves in a process plant, and whether optimum conditions for refining one mineral are different to those for refining another. For example how does refining copper from chalcopyrite differ to refining copper from bornite?Minerals are naturally occurring inorganic solids that have a definite chemical composition and an ordered atomic (crystalline) structure. X-ray diffraction is a common and highly developed method to identify and quantify minerals. X-rays are fired onto a material and the mineral is identified by the angles where the diffracted X-rays are in phase.Most X-ray analyzers are laboratory based. A sample is prepared and analyzed by a detector that travels in an arc to collect the diffraction pattern. COSMA has a curved detector which picks up the complete x-ray pattern instantaneously. Therefore, material is collected and transported through the machine where is it is analyzed continuously.COSMA measures about 0.5 tons of material per day, while laboratory analyzers measure a few grams at a time. Real time data trends are produced allowing for improved process evaluation and automatic control. The COSMA on-line system has taken X-ray diffraction out of the laboratory into the field.There are a number of systems in operation in cement production. It is recognized that on-line mineral analysis has a role in many other processes. This paper presents the technology and invites further discussion should the technology be beneficial to members of the audience.INTRODUCTIONThis article describes COSMA, a system that provides direct and continuous on-line mineral analysis using X-ray diffraction in the field. While X-ray diffraction is a common technique used in mineral analysis, the time from sampling to analysis can be hours and plant operators typically do not get the data in time to control a process or respond to an upset. COSMA provides rapid measurement, analysis and feedback of data, in real time. This provides powerful information that can be used to optimize operation, thereby reducing costs and increasing quality."

Jan 1, 2009

By J. D. Robertson

An in situ water sampling device has been developed to measure biologically-available or “labile” metals in natural waters and effluents. The active mechanism involves the use of a polyacrylamide gel layer to quantitatively control metal transfer to a trace-metal-adsorbing, gel-imbedded resin. Because the resin only adsorbs free metal ions (the gel sampler methodology is a kinetic speciation technique), and because metal bioavailability is related to the free-ion activity, the device provides a direct measure of the biological-availability of metals in the environment sampled. The prototype consists of a layer of ion-permeable polyacrylamide gel which separates the solution to be sampled from an ion exchange resin. Because approximately 90% of the polyacrylamide gel is water, mass transport through the gel is diffusion-controlled, and is therefore well defined. Metal ions are rapidly bound by the resin, creating a steep concentration gradient in the gel. The amount of labile trace metal that accumulates on the resin can be related directly to the concentration of the metal in solution, the exposure time and the molecular diffusion coefficient of the labile species. In addition, the passive nature of this device affords it the potential to address many of the limitations presented by conventional sampling methods, such as sample contamination introduced during collection or filtration and changes in trace metal speciation prior to analysis. Laboratory studies and limited field trials indicate that the sampler behaves as anticipated and illustrate that biologically- available metal concentrations in many environments are a small fraction of the total concentrations and often significantly less than the dissolved concentration. The implications of this on regulatory criteria are discussed. Additional field trials and correlation with bioassays are currently underway.

Jan 1, 2000

By Jim Wickens, Vince Lofftus, Mark Kravetz

"This paper discusses how Bald Mountain Gold Mine (Ely, NV) dramatically reduced mercury production by treating process solutions with a liquid reagent based on organic sulfide chemistry. Cherokee Chemical Co. Inc. (Vernon, CA) markets this reagent as UNR 81 1A.A summary of the bench tests comparing various reagents is given. The ensuing plant trial is discussed and successful mercury removal results are presented. Data is presented to show that early removal of mercury in the process reduces the amount of mercury collected at retort. Data is also presented to show that use of this reagent does not reduce gold recovery. Plant trial treatment costs are discussed. Finally, the potential of this technology to substantially reduce closure costs as compared to traditional mercury removal options is discussed.INTRODUCTIONBald Mountain Mine produces gold. Mercury is a costly by-product of gold production because no revenue is generated from mercury. Traditionally, mercury leaches out with gold and follows the gold throughout the processing circuit until it is eventually condensed and collected at Retort. Minimizing or eliminating mercury production minimizes worker health and safety risks, minimizes environmental liability, and reduces costs. In the long term, minimizing mercury production will make mine closure easier and less costly.Bald Mountain Mine dramatically reduced mercury production by treating process solutions with liquid reagents called UNR 811 and UNR 811A. Several reagents were bench tested before proceeding with a plant trial. The reagent complexes the mercury to form an insoluble organic sulfide precipitate. In independent tests, the precipitate passed acid mobilization tests and is considered stable."

Jan 1, 2001

By P. H. Agson Gani, T. Sitorus, N. P. Widodo

"PT ANTAM UBPE Pongkor underground mine use blasting to develop its tunnels which will cause poisonous and dangerous gases trapped inside mine. To analyze this case, a study of mine ventilation, the dispersion of carbon monoxide (CO) gas concentration and diffusion coefficient is commenced. At the end, the re-entry time formula will be determined. Results indicate that this study is site specific and could only be applied in the place this study executed. The aim of this study is to be further developed by applying Principal Component Analysis (PCA) to find a universal re-entry formula. KEYWORDS Mine Ventilation, Re-Entry, Smoke Clearing, Diffusion Coefficient, Carbon Monoxide Gas, Gas Dispersion INTRODUCTION Pongkor underground mine is using cut and fill as its mining method. Thus, its development and production processes require blasting to develop its tunnel. This process caused poisonous and dangerous gases spread and trapped inside the mine, one of them is carbon monoxide (CO) gas. CO is formed in an unbalanced reaction of explosives detonation and could be the cause of headache, blackout and death to people who inhale CO at certain concentration (McPherson, 2011; Hartman, Mutmansky, Ramani, & Wang, 2012). Mine ventilation system is installed in the mine to resolve this problem. Mine ventilation play an important role to disperse CO gas by absorb the poisonous/dangerous gases and deliver clean air into mine. The important parameter is diffusion coefficient, because diffusion is affecting particulates or gasses spreading from its sources throughout the mine. Diffusion coefficient is the total diffusion in axial direction of turbulent flow mainly by convection of bulk motion, advection and eddy diffusion, while the effect of molecular diffusion is appreciably negligible (Widiatmojo et al, 2015). Taylor (1953, 1954) develops a theory about the dispersion by inducing a slow stream of solvent into a capillary tube. Taylor used Reynolds assumption of radial diffusivity to be analogous with the transfer of the matter in turbulent flow as well as the transfer of momentum and heat. Then, Taylor proposed the formula of diffusion coefficient, D (m2/s), against pipe diameter and turbulent shear velocity are as follow:"

Jan 1, 2019

By Barry D. Simmons

"A well-defined approach is essential to ensure the long-term success of a regional exploration program. Teck's approach in eastern Canada is designed to fulfill corporate objectives while recognizing certain unique parameters for exploration in the area. The elements of this approach include clearly defined objectives, technical considerations and personnel policies, all of which are equally important. The goal is a significant discovery before the mid-l990s and the company is confident that this target will be achieved.IntroductionAs one of Canada's oldest continuously operating mining companies, Teck Corporation traces its roots to Kirkland Lake, Ontario, with the development of the Teck-Hughes gold mine in 1913, later supplemented by production from the Lamaque gold mine in Val d'Or, Quebec. Control of the company was acquired by Temagami Mining Company, part of the Keevil Mining Group, in 1959. Credited as one of the first discoveries made using airborne geophysics, the Keevil Group had recently found the small but very high-grade copper deposits at Temagami, Ontario. These developments in eastern Canada formed a foundation for remarkable growth and Teck's present status as one of Canada's most successful and respected mining companies.Teck currently operates successful mining ventures across Canada and has international exposure through its association with Cominco Ltd., M.I.M. Holdings Limited and Metallgesellschaft AG. Operations in eastern Canada, however, remain an important component of Teck's ongoing success. The David Bell and Williams mines at Hernlo, Ontario, are Canada's lowest cost and largest gold operations, respectively. The Niobec Mine at Chicoutimi, Quebec, is North America's only significant producer of niobium. Teck maintains a 45070 interest in Golden Knight Resources Inc., part owner of the successful gold mining operation in the Casa Berardi area of northwestern Quebec. As a significant shareholder in Aur Resources Inc. and as a part owner, Teck is participating in the development of the Louvicourt deposit, a major base metal discovery at Val d'Or, Quebec."

Jan 1, 1992

By S. Haggarty

"Wholly owned by Corona Corporation, the Nickel Plate Mine is an open pit, gold mining operation located near Hedley, 50 km west of Penticton, in Southern British Columbia.Milling capacity is 3,400 SDT /Day with an average feed grade of 0.080 Oz Au/Ton. Gold processing involves three stage grinding including tertiary pebble milling, two stage cyanide leaching and filtering and Merrill-Crowe zinc precipitation.A summary of process improvements required to increase milling capacity above the initial design tonnage of 2, 700 SDT /Day are described -Installation of a 42"" x 65"" Allis Chalmers Gyratory crusher replacing a 42"" x 48"" Traylor jaw crusher.Installation of polyurethane screen panels replacing woven wire cloths on an 8' x 20 ft triple deck screen.Installation of a hopper clarifier to reduce filtrate turbidity.Automated control of solution balancing and effluent treatment circuits.INTRODUCTIONThis paper describes mining and milling practices at the Nickel Plate Mine and details post start-up process modifications which were required to attain design tonnage.Wholly owned by Corona Corporation, the Nickel Plate Mine is an open pit, gold mining operation located near Hedley, 50 km west of Penticton, in Southern British Columbia.Mining capacity from the open pit is approximately 32,000 TPD with an average waste/ore ratio of 8.4:1.Milling capacity is 3,400 SOT/Day, above initial design tonnage of 2,700 SOT/Day. Feed grade averages 0.08 Oz Au per ton yielding 85,000 troy ounces of gold per year."

Jan 1, 1991

By A. Sobering, G. N. Carlson

"This paper describes the conversion of the grinding section of the W a bush Mines pelletizing plant from conventional wet, open-circuit trunnion overflow ball milling, with filtering, and bentonite mixing on a common conveyor belt, to dry, open-circuit, grate discharge grinding, with pug mill mixing of bentonite and water at individual mills.The test work and data on operating economies to justify the cost of conversion are given. It is too early, at the time of writing, to have complete operating confirmation, but data are available. A brief description of the original plant is included."

Jan 1, 1971

By M. J. Collins

The Advocate Mines Limited asbestos property is 6 km north of Baie Ve rte on the northeast coast of Newfoundland. Mining began in the early 1960s and was concluded in 1981. The chrysotile asbestos deposit lies at the north end of the Baie Verte Lineament, the interface between a closing ocean floor and continental margin. Asbestos occurs within ultramafic rocks of abducted ophiolite massifs that were thrust westward against Fleur-de-Lys Supergroup metasediments (continental rise sediments) in the Lower to Middle Ordovician. The asbestos-bearing ultramafics belong to the Central Ultrabasic Sequence of the Advocate Complex. Serpentinized peridotite of this sequence has a 'waste cap' core that grades outward to increasingly sheared rock. Asbestos is found mainly in a northtrending, basin-shaped zone surrounding the core, specifically within fractured serpentinized peridotite that abuts the sheared rock. Asbestos appears as stockworks of chrysotile cross fibre veins and is concentrated between brown, narrow brucitic dunite dykes and sills. Shear contacts commonly surround the ultrabasic body. Cross faults and complex Jointing also exist. The Advocate Mines Limited mill produced 65,000 tonnes of Group IV fibres and 1 l , 000 tonnes of Group VJ fibres annually. The bagged product enjoyed markets worldwide.

Jan 1, 1984

By Joseph N. Bakambu

It is currently recognized by mining society that autonomously guided underground mining vehicles may greatly increase the efficiency of mining production and improve human safety. Recent results in mobile robotics, data fusion and sensor development provide a solid basis for solving the problems related to autonomous underground navigation. Recently developed commercial systems mostly rely on the infrastructure that is expensive and difficult to maintain. Guideless navigation in unstructured and harsh environment of underground mines is still a challenging task. In this paper, we describe an autonomous navigation system for an underground mining vehicle equipped with on-board dead reckoning, inertial and optical sensors. This system does not require any artificial infrastructure and is capable to guide the vehicle along the complex environment of interconnected underground drifts; it also ensures the detection of obstacles on the vehicle path. The user interface for monitoring and control is described and the results of laboratory tests and on-site experiments are presented. Work in progress addresses the system integration for real equipment, and the system upgrade, adding map-building and selflocalization capabilities .

May 1, 2002

By Ho-Sung Yoon, Jyothi Rajesh Kumar, Chul-Joo Kim, Sung-Don Kim

A recovery process for rare earths (REs) such as dysprosium and neodymium from the leach liquor of permanent magnet scrap (PMS) was developed. The two hydrometallurgical routes namely liquid-liquid extraction (solvent extraction) and selective stripping were implemented. The present study deals with the separation and recovery process development by using organo-phosphorous based extractant di-(2-ethylhexyl phosphoric acid (D2EHPA) as reagent for REs processing. Initial studies considered the influence of time on the extraction process, as well as pH and extractant concentration effects. This suggested the aqueous mechanism and separation factors played a role in process during development. McCabe-Thiele diagrams for extraction isotherms were developed. Counter current extraction (CCE) using various phase ratios influenced metals separation. Maximum loading capacity of the D2EHPA was determined. The loaded organic generated by the CCE process was water washed followed by a scrubbing process to remove the other metal ion from targeted metal. Finally, a stripping process was tested using various mineral acids.

Jan 1, 2015

By Thomas Clark

This report presents a review of the distribution and exploration potential of platinum-group elements (PGE) in Québec; it is based on published and unpublished analytical data. This qualitative evaluation of the PGE potential, whether in PGE-dominant deposits or in Ni-Cu-dominant deposits with co-product PGE, is based on interelement ratios such as Ni/Pd, Cu/Ir, Cu/Pt, and Cu/Pd. Good PGE targets, i.e., deposits associated with magmas fertile in PGE, are identified. Less favorable PGE targets, i.e., deposits associated with PGE-depleted magmas, are also mentioned. The importance of exploring for deposits similar to those at lac des Îles and East Bull Lake (Ontario) is emphasized.

May 1, 2001

By B. R. MacKay

Introduction Of all Canada's mineral resources, its coal deposits have probably received the most continued attention by the Geological Survey since its inception ninety years ago. A casual review of the many geological maps of coal areas by the Geological Survey will show how geological and topographical detail on the maps has gradually increased to meet the ever urgent demands of the mining industry. In the early stages of exploration, the mapping done, especially in the coalfields of the Rocky mountains, was largely of a reconnaissance nature. On these maps the topographical relief, where shown, is indicated by form lines or by hachures, the boundaries of the coal-bearing formations are only approximately defined, and the geological structure of the coal seams is illustrated by one or more generalized cross-sections. Once mining development on a coal area began, there arose a demand for more detailed maps. To meet this need, topographical and geological maps on a scale of one inch to a mile were made, in which the ?topographical relief is shown by contour lines having generally an interval of 100 or 200feet. On the geological maps, the boundaries of the formations are accurately delineated, and the geological structure of the area is illustrated by one or more structure sections drawn across the area, which show the position and attitude of fault lines, the crests and troughs of folds, and the attitude of the various formations (See maps of Costigan Coal Field, 1905, and Cascade Coal Basin, 1907, by D. B. Dowling).

Jan 1, 1932

By D. Seo, P. Au, X. Husang, D. Nagy

The production of single crystal (SX) turbine blades represents the current stateof- the-art in Ni-based superalloy design. With complex casting processes and alloy composition modifications, SX superalloys exhibit superior high temperature mechanical properties to their polycrystalline counterparts. Stresses and plastic deformation can occur in SX nickel-base superalloy engine components at various stages during their manufacture and use. For examples, stresses are created during initial solidification and also during solid state processing such as shot peening, grit blasting, blending, electrodischarge machining and welding. Stresses may also be created during service due to random events such as foreign object impacts. Subsequent exposure of SX to high temperatures during solution heat treatment and brazing repair can result in recrystallization which has been shown to be detrimental to both creep rupture strength and fatigue performance of the components. It is therefore the objective of this paper to understand the recrystallization behavior of two SX superalloys, PWA 1484 and 1483, subjected to pre-stressing and subsequent heat treatments.

Jan 1, 2006

By L. A. Kaufman

"AbstractThe Bureau of Mines, Ottawa, in conjunction with Eldorado Mining and Refining (1944), Limited, has developed an automatic concentrator for uranium ores.A brief review of radioactivity is given which shows the present limitations for obtaining •good results by electronic concentration. The ores after being mined, or at any other stage of a concentrating process, can be analysed for the uranium dissemination and from these results the possibility of an economical concentration can be estimated.The electronic and mechanical parts of the equipment are described. Difficulties in the operation's, and means by which they have •been and are •being overcome, are discussed. The capacity of the units, the results obtained, the man-power required, and other pertinent data are presented. Simple control analysis on the percent U3O8 has been developed.Research is continuing along lines to develop a more completely automatic unit using a scintillation detector, and applying a few new ideas and some devices that have been developed in colour sorting.IntroductionIt is well known how important the Geiger counter is in the field of exploration for uranium. It was in late 1946 that Dr. C. Lapointe, of the Bureau of Mines, Ottawa, first started work on an automatic picking unit to concentrate uranium ores. He used the principle that if a number of pieces of unknown ore, some of which contained uranium, were individually brought up close to a Geiger-Müller tube, then the pieces containing uranium could •be easily picked out due to their activity. Since then a good deal of work has been done by the Bureau of Mines in conjunction with Eldorado Mining and • Refining (1944), Limited, to develop an electronic concentrator."

Jan 1, 1950