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By E. J. Schwarz, A. A. Winir

"Absolute magnetite contents were determined for asbestos specimens in various stages of milling by using a Faraday-type thermomagnetic balance. Comparison of these results with magnetic ratings (MR) supplied by the mining companies cooperating in this study reveals strong scatter. The main cause of this scatter is thought to be that the MR values were obtained in magnetic fields well below the saturating field of magnetite (5,000 oe). However, only the saturation moment is an intrinsic property and consequently must be used for the purpose of obtaining reliable estimates of the magnetite content. Curie points indicate that virtually pure magnetite and possibly Ni3Fe is present in all samples, and another phase, probably (Cr, Al) magnetite, is present in a few samples. The susceptibility in fields stronger than 5,000 oe is positive and falls in the normal paramagnetic range, whereas sy nthetic chrysotile exhibits weak diamagnetism. This suggests that, as a general rule, the least adulterated natural chrysotile concurs with the samples showing the smallest positive susceptibility above 5,000 oe. The magnetite appears to increase in quantity with a decrease in fibre length and to be somewhat more uniform in distribution for samples showing substantial fiberization (opening of the fibres)."

Jan 1, 1971

By Andrew Bamber

A fast and objective spreadsheet-based model for the financial evaluation of innovative mining and processing strategies such as pre-concentration vs. a conventional base case is presented. The size and grade of the deposit must be chosen, from which a mining rate is selected. Expected operational data for the deposit as well as any mill testwork and results from the pre-concentration testwork are entered as input variables on the sheet, and cost and revenue impacts are calculated in the ?Output? sheet. A capital sum and operating costs for the initial mine and mill development as well as the pre-concentration facility are calculated. The net changes in capital and operating costs are calculated, and impacts on revenue through changes in metal recovery are also calculated. These outputs are used to calculate the overall impact on the cutoff grade and thus the size of the mineral reserve using a generic grade-tonnage model. The NPV and NPV profile of the two scenarios is calculated, with variations in basic parameters such as operating cost, capital requirements, metal price or grade as well as discount rate. Cost and revenue impacts are evaluated and compared to the baseline to establish a positive or negative impact overall. Different scenarios of grade, tonnage, mining rate, process performance, capital and operating cost structure can be explored using the model. Outcomes projected by the model for case studies conducted thus far have been calibrated against internal estimates by the sponsoring organizations and found to be accurate to within 30%, confirming the utility of the model in practice.

Oct 1, 2009

By P. C. M. Knops, K. Rijnsburger, R. M. Santos

To overcome the challenges of mineral CO2 sequestration, this work utilizes a unique proprietary Gravity Pressure Vessel (GPV) reactor technology, and focuses on reaction products of high economic value. The GPV provides intense process conditions through hydrostatic pressurization and heat exchange integration that harvests exothermic reaction energy. Here, laboratory-scale tests of the envisioned process was performed in tubular and continuously stirred tank reactor (CSTR) autoclave reactors. The mineral used was Olivine (~Mg1.6Fe2+0.4(SiO4) + ppm Ni/Cr), although asbestos, steel slags and oil shale residues are also under investigation. The effect of several process parameters on reaction extent and product properties was tested: CO2 pressure, temperature, residence time, additives (buffers, lixiviants, chelators, oxidizers), solids loading, and mixing rate. The products (carbonates, amorphous silica and Chromite) were physically separated (based on size, density and magnetic properties), characterized (for chemistry, mineralogy and morphology) and tested in intended applications (e.g. as pozzolanic carbon-negative building material). Economically, it is found that product value is the main driver for mineral carbonation, rather than, or in addition to, the sequestered CO2. The approach of using a GPV and focusing on valuable reaction products could thus make CO2 mineralization a feasible and sustainable hydrometallurgical process.

Jan 1, 2015

By V. Bondarenko

The importance and necessity of gas hydrates deposits development followed by natural gas extraction is considered in the present paper. Analysis is given to world sources focused on methane hydrates formation conditions. Information covering the most perspective gas hydrate deposit of the Black Sea is presented in the article. Two most common methods of gas hydrates development ? thermo stimulation and inhibitor injection are analyzed presenting their comparative characteristics. Basic scientific trends and developments of underground mining department in the field of gas methane extraction from gas hydrates are scrutinized. Schemes and methods of natural gas hydrates development are shown together with formulas, parameters and factors influencing the extraction process. Also the analysis is given to the possibility of gas hydrates formation from methane-air mixtures of degassing wells from coal mines of Ukraine. Improved experimental unit for gas hydrates formation under laboratorial conditions is presented with its basic characteristics. General conclusions and basic tasks requiring further research are given in the end.

Aug 1, 2013

By John (Jack) D. Young, Frank M. Wheeler

Metallurgical plants are typically large, complex facilities. Their design is a multidisciplinary activity with a wide range of inputs, based on: the business case; metallurgical and process requirements; and the main processing equipment selection. Many constraints limit what can be achieved. Appropriate phasing of the design and development, and clear go/no-go decision criteria, are critical to successful implementation of a plant design project. Risk management concepts are used as a framework for successful project development, working from the business case, through project development, to implementation and startup, paying constant attention to technology, safe design, and sustainability. 1.1 INTRODUCTION The subject of “Metallurgical Plant Design” is the design of metallurgical plant facilities in the broadest sense. Plant design represents the culmination of many multidisciplinary activities: knowledge of process metallurgy is applied to design facilities to manufacture useful, economical, metal-based products. In the field of metallurgy, plant design is often overlooked, and its unique requirements are commonly not well understood, let alone appreciated. This book is a contribution to remedying this situation. The focus is the specifics of the metals industries, because an extensive literature already exists on the general topic of plant design.

Jan 1, 2015

By F. Bourgeois, J. -S. Kroll-Rabotin

ABSTRACT: Falcon concentrators are enhanced gravity separators designed for concentrating fine particles. The Falcon UF model is unique in that it is dedicated to beneficiation of ultrafines, one key feature being that it does not make use of any fluidization water. We investigated the physics of particle transport inside Falcon concentrators, and concluded that separation efficiency is governed by differential settling velocity. We derived and published a predictive model of the partition function under dilute conditions. We intend to extend the initial model to concentrated ultrafine suspensions for application to industrial scenarios by adding hindered settling to account for solid concentration effects.

Jan 1, 2011

By O. Babak, J. G. Manchuk

ABSTRACT A significant factor in evaluating bitumen recovery from an oil sands mine is the particle size distribution (PSD). Increased understanding of mined ore quality and improvement in predictions of recovery can be achieved through PSD modeling. This paper addresses PSD modeling using geostatistics. PSDs may be described using many discrete particle sizes, making this a challenge. The approach parameterizes PSDs with a few statistics. A lookup table is used to reconstruct the PSDs based on models of the statistics. The workflow is applied to Total E&P Canada’s Joslyn Lease and yields good results that reproduce input statistics without introducing artifacts.

Jan 1, 2013

By A. S. H. Kabir, I-H. Jung, J. Su, Yue. S., M. Sanjari

One of the major problems associated with conventional wrought magnesium alloys is the unwanted basal texture that forms during plastic deformation which generally does not change markedly after post-deformation annealing. Formation of precipitates on the recrystallized grain boundaries during annealing may affect the usual rotation of grains towards preferred basal direction resulting in texture weakening. In this study, Mg-Al-Sn alloy was hot compressed at 250°C and annealed at 350°C for various times. The initial as-deformed microstructure was partially dynamic recrystallized with dynamic precipitates on the grain boundaries. After annealing at 350°C, static recrystallization of the bimodal microstructure took place where at this temperature no static precipitates formed. The goal of this work was to study the effect of dynamic precipitation on the texture evolution during the annealing process. Texture evolution was studied during annealing by electron backscattered diffraction (EBSD) technique through a microstructure tracking process. It was found that precipitates on the recrystallized grain boundaries have significant effect on the usual rotation of the grains towards the basal direction, meaning significant texture weakening, which is beneficial for final mechanical properties.

Jan 1, 2015

By John Ratti

Building on Canadian Capabilities for Space Resource Missions: Space resource science and technology mission building blocks Canadian historical perspective Status and future pursuits It takes Canadian Teamwork to succeed in space exploration! Space resource science and technology building blocks: Orbiting / Delivery Elements Spacecraft Sensors Landed elements Roving / Mobility, Autonomy Sample acquisition and handling Sensors, GN&C Science Operations Partnerships: Government ? Industry Between Industry With Academia and Scientists

May 1, 2013

By H. Nouranian, M. Askari

GOLGOHAR Mining & Industrial Co., with annual production of 16 million tons, is one of the largest pelletizing and iron ore supplier in Iran that recently this year, because of using mineral processing techniques and extraction of ore body positioning between the metamorphic rocks, about 150 million tons of dry tailings has been created as a result of concentrate production. On the other hand, many environmental issues such as groundwater pollution have been developed by sulfide and silicate gangue minerals, which containing heavy metals such as mercury and arsenic. In this study, a new product with high added value has been introduced for the company by identification and extraction of industrial minerals in dry tailings. Also, by removing large masses of dry tailings, environmental pollution sources were gradually eliminated. This method can be used as a modern waste management approach in the world.

Jan 1, 2017

By V. L. Eardley-Wilmot

Diatomite as prepared for the market is a fluffy, white powder, remarkably light in weight-it weighs only 10 to 15 pounds per cubic foot, or one-tenth as much as sand. Being extremely porous and inert, it is in large and increasing demand for insulation and filtration purposes, as general filler, and for many other uses. Structure Structurally, diatomite is quite different from any other known commercial material. It is composed of myriads of microscopically small, siliceous shells of diatoms which belong to a group of flowerless aquatic plants called algae. When these plants die, the siliceous remains sink to the bottom of the water and form beds of diatomite. Over 8,000 species of diatoms are known, named, and tabulated. The intricate scroll-work and patterns on many of these are one of the marvels of nature, and yet so small are they that from 40 to 70 million separate diatoms may be contained in one cubic inch of material. However, the size and shape of these diatoms, which vary greatly (compare Figures 5 and 6), have an important bearing on the commercial use of the diatomite. The diatoms in the majority of the known deposits are so typical of that deposit that, after a micro-examination, an expert can usually tell not only from what part of the world, but also from what particular deposit, the sample has come.

Jan 1, 1931

By A. Jafarnia

Aluminum alloys are frequently grain refined during solidification in order to promote the formation of an equiaxed grain structure in the casting. The application of Ti-based grain refiners and/or Ti containing master alloys for improving mechanical properties may result in formation of Al-Ti based intermetallics. Although the grain refinement produces many desirable qualities in aluminum castings such as improved castability and mechanical properties, the addition of Ti to Al-Si foundry alloys may lead to the formation of some undesirable intermetallic particles such as AlTiSi and cause a number of operational problems such as nozzle blockage due to segregation and agglomeration of aluminide particles within the nozzle. There are several questions to be clarified when minor amount of Ti is added to Al-Si alloys. They include nucleation and growth of AlTiSi particles, their morphologies and orientation relationships with aluminum matrix and the dissolution of these intermetallics during the course of solidification and/or post solidification treatments. The current study was initiated to study the process and possible mechanism of aluminide dissolution and the related phenomena such as segregation and agglomeration. It reports the results found during reheating of laboratory prepared Ti-added A356 alloy at three temperature ranges of below solidus, mushy zone and above liquidus.

Jan 1, 2004

By Lawrence Devon Smith

"This paper examines the impact of the various assumptions that go into an economic evaluation, and shows how these can be combined to show an exciting result that may not really exist. An example of an embellished case (the kind that one frequently sees when projects are being promoted) is developed and the cumulative impact is analysed to show the actual project underneath. The paper also points out some areas to watch for overly optimistic assumptions such as prices, inflation, and debt. The concept of a ""bare bones"" base case is proposed (constant metal prices, constant dollars, no inflation, no debt, no interest, on a project basis, after tax) as a common reference point.As well, the discount rate is examined as a fundamental means of reflecting risk in discounted cash flow evaluations. Current industry practice is discussed, and a methodology for the analysis of risk levels is proposed that assesses the constituent components of the discount rate: real interest, mineral project risks, and country risk.INTRODUCTIONOften, the first time that all of the technical and economic data for a mineral project comes together in one place is when the economic evaluation is developed. This typically happens when work on the project has progressed to a sufficient level of detail that the effort to produce a year-by-year cash flow is justified, usually at the pre-feasibility or feasibility study stage. The data involved will include:• production; tonnes waste and ore mined, ore grade, mining recovery, metallurgical recovery, metal sold• revenue; metal price, smelting & refining charges, marketing costs• operating Costs; mining, milling, administration, fees, royalties• capital Costs; exploration, development, construction, indirect costs (engineering, management), contingencies, start-up, inventories, working capital, replacement and sustaining capital, closure costs• taxes and royalties• exclusions; depreciation (this is not a cash item), sunk costs (only costs going forward)."

Jan 1, 2003

By H. L. Cameron

Introduction Since the beginning of gold mining in Nova Scotia in the year 1860, the biggest problem o the mine operators has been to find and follow the ore zones in the narrow quartz veins. It was early recognized that all veins were not gold bearing and that, in those that were, the commercial ore was confined to limited zones. A large number of geologists and mining engineers have been interested enough to give time and thought to the problem, but, until the last four or five years preceding World War II, they were handicapped by lack of exact data from mining operations. The necessary data could only be obtained by daily checking of underground operations. Such daily checks were instituted at a number of mines during the period 1935-40 and, in every case, were successful in delimiting the ore zone or zones for the particular mine. The present paper deals with the results of this work as applied to practical ore finding. It is an attempt at extrapolation, from observations in the four districts with which the writer is personally familiar, co other districts in which similar conditions or structures are reported.

Jan 1, 1947

By K. Ogawa, T. Yokoyama

Hydraulic fracturing technique, an applied technique to cause tensile fractures to rock by injecting water pressure to a certain closed section of the borehole, is a measurement method of in-situ rock stress. This technique has the highest track record for techniques used in sub 1000 meter. A feature of this technique is comparatively simple and easy for in-situ stress measurement, because the measurement is applicable when a drilled borehole is available. The predominant advantage of this method is that elastic constants such as Young’s modulus and Poisson’s ratio are not required for determining the value and direction of initial stress. The factors to determine the stress state are the water pressures of re-opening and shut-in of fractures around the borehole wall and its directions. With conventional methods, however, the accuracy of the derived stress states from the observation equations was often adversely affected by the lack of consideration of the remaining water pressure in fractures and insufficient stiffness of the pressurization system. We have developed a new hydraulic fracturing system based on a new test method concept overcoming these defects, and applied to a 300 meter deep borehole in granite. The most important improvement of the new system is an employment of a syringe pump which enables an accurate flow control of fluid with less than 1ml/min in the pressure of 30MPa. Therefore the new test system has a quick response for pressurising in the interval zone, and the measured data was confirmed extremely accurate.

Jan 1, 2015

By W. H. Patterson

The history and experience of early companies in the Islands is illustrated by the typical transactions of Trans-Western from 1959 to date. Trans-Western had entered into farmout agreements with companies strong enough to carry out at least the required minimum exploratory work and then such development as might be warranted. The farmee companies were required to make deposits to guarantee work performance during the first period of validity, i.e. the first 3 years of the 12-year life of the permits, and at the rate of 5 cents per acre. At that time, a good deal of geology was available, as a result of extensive exploration that had been carried on by the Geological Survey of Canada and other geological enterprises, with field parties travelling over and camping on all of those Islands. Trans-Western's farmees then selected, from Trans-Western's priority on 13.5 million acres, what they believed were the lands most prospective of producing large oil and gas discoveries, and, having the right to trim off acreage which they considered less prospective, thereby reducing the acreage of Trans-Western and its farmees to in excess of 5.5 million acres. The farmees then commenced a 3-year program carrying out geological exploration to the required minimum of 5 cents per acre, and with some permanent and many mobile camps.

Jan 1, 1969

By H. Utsunomiya, J. Su, K. S. Tamimi, S. Yue, M. Sanjari, L. Kestens, A. S. Kabir, R. Petrov

The recrystallization and texture evolution of AZ31 sheets obtained through two stages was investigated at different stages of post-rolling annealing. The specimens were rolled at the temperature of 100? and at a fast speed of 1000m/min and low speed of 15m/min with a reduction of 30% in one pass. The results show thatAZ31B sheets rolled at 15 m/min and 100 °C has fractured for reductions of more than 30% per pass. However, by increasing the rolling speed to 1000 m/min the rollability was improved significantly and the material can be rolled to reductions of more than 70% per pass. The high speed and heavily deformed materials are fully recrystallized even at 100 °C.

Jan 1, 2015

By ByongPil Lee, Changkyu Lee, Jin Gyun Park, Hyung Sub Eom, Sung-Koo Jo, Jae-Young Lee, Gilsoo Han

"A new hydrometallurgical process for nickel extraction from a low grade laterite ore such as limonite has been developed by RIST and POSCO. This POSCO Nickel Extraction Process (PosNEP) consists of five main processes: ore reduction using hydrogen as a reductant; acid leaching at atmospheric pressure and temperature; cementation by the use of reduced-ore seed; production of the main product such as ferronickel or a high purity nickel compound; and production of by-products such as cobalt and iron in the forms of cobalt sulfate and iron oxide. In addition, hydrogen produced in acid leaching and hydrochloric acid regenerated in pyrohydrolysis for iron oxide production can be reused in the process, which makes PosNEP more cost-effective. The performance of PosNEP has been proven through pilot tests, showing that this process is economically and technically viable. In this paper, basic concepts and detailed test results of PosNEP are shown.INTRODUCTIONNickel has been extracted from two types of ore, sulfide and oxide ore. Nickel and cobalt usually occur together in the ores. The principal ore mineral of the sulfide is pentlandite, (Ni,Fe)9S8, which is easily beneficiated to produce sulfide concentrates(Moats & Davenport, 2014). These concentrates are usually treated by smelting and converting to make a matte. The produced matte is then purified through either hydrometallurgical or pyrometallurgical processes to produce high-purity nickel. In general, this process for sulfide ore has been known as a more cost-effective process than that for oxide ore.The oxide ore is laterite comprised of two different ore types, saprolite and limonite. The main nickel-bearing mineral of saprolite is nickeliferrous garnierite,(Mg,Ni)6Si4O10(OH)8, and that of limonite is nickeliferrous goethite (Fe,Ni)O·OH ore (Moats & Davenport, 2014). Since the saprolite has high contents of nickel and slag formers (MgO and SiO2) and a low content of iron, it tends to be treated by a pyrometallurgical smelting process such as calcination and electric furnace techniques to produce ferronickel for use in stainless steel. In this process, the cobalt in the ferronickel does not have any economic value."

Jan 1, 2017

By T. Guan, G. Fu, X. Zhou, L. Deng

"Currently, tailings water is required to be recycled in minerals processing plants. When the flotation tailings water of complex copper-sulfur-tungsten polymetallic ore is reused to the flotation of copper-sulfur ore, a portion of tungsten would be lost in copper concentrate or sulfur concentrate due to the addition of the collectors used for oxidized ore which are also effective for the sulfide minerals in the process of tungsten flotation. At the same time, the technical index of copper concentrate and sulfur concentrate would be seriously affected by tailings water. Our experimental researches of many years show that the copper concentrate with a grade of 18.36% Cu at a recovery of 76.67% is obtained for the raw ore containing 0.60% Cu, 18.99% S, 0.16% WO3 in small locked cycle test using recycled water, through simple pretreatment of the tailings water from tungsten flotation and adding special regulator CW and new tungsten collector TM. The result is close to the performance without using tailings water. And, in the continuous pilot experiment which was continuously conducted for 4 days with the same technology, the following results was obtained: the copper concentrate with a grade of 21.74% Cu, the recovery was 71.55%; the sulfur concentrate with a grade of 45.16% S, the recovery was 80.10%; the tungsten concentrate with a grade of 42.63% WO3, the recovery was 54.62% relative to raw ore (the recovery relative to scheelite was 76.47%). The throughput of the continuous pilot experiment is 1.0~1.2 t/d, and the raw ore contains 0.56% Cu, 18.80% S, 0.14% WO3 on average.INTRODUCTIONMining industry is one of the most important developing fields, it supplies raw materials for industrial production as well as discharges much waste water. Tailings water is the main source of beneficiation waste water, it would result in severe environmental pollution if discharged directly. Generally, the tailings water would bring undesirable effect on flotation index after simple pretreatment by lime (Kalin, Fyson, & Wheeler, 2006). On the other hand, the treatment of tailings water through ion-exchange (Cui & Liu, 2015) before recycling is of high cost. Generally, in the flotation of Cu-S-W polymetallic ore, when the tailings water from tungsten flotation is treated simply by lime and recycled to the flotation of sulfide minerals, the flotation index of sulfide minerals decreases, and a portion of oxide mineral would be lost in the sulfide concentrate. As a result, the recycle rate of this kind of tailings water is relatively low, some of the tailings water is discharged after simple treatment and then environmental pollution is caused subsequently. One of the effective ways to improve beneficiation performance and increase the recycle rate of tailings water is to conduct research on developing recycle technology for flotation tailings water of complex copper-sulfur-tungsten polymetallic ore."

Jan 1, 2016

By F. A. McLean

The past decade has witnessed a rapid increase in the number and variety of uses found for internal combustion engines in mining operations. Gasoline engines are now widely used for operating core drills, pumps, compressors, small hoists, switching locomotives, tractors, boats, and other equipment. The heavy-oil engine is employed for operating compressors, generators, shovels, ore-milling machinery, and- in the iron, copper, and coal districts- in connection with that' latest newcomer in modern railroading, the oil-electric locomotive. Each of these applications could well form a subject for a lengthy treatise in itself. This paper, however, will be confined to a discussion of some of the features of internal combustion engines as applied to mine compressing plants and mill drive. Perhaps at no time in the history of mining in Canada has the search for new mines been more vigorously carried on, more old properties rejuvenated, or more remote districts exploited than during the past three years. The mine operator of today has a far wider range of equipment and facilities at his disposal than had the pioneers of Rossland, Cobalt, or Porcupine. Each year now witnesses the hinterland driven farther and farther back as improved forms of transportation, machinery, and methods make possible the exploration of properties once considered too inaccessible to warrant serious attention. Howey, Sherritt-Gordon, Callinan-Flin Flon, Jackson-Manion, Picard Gold Mines, and a number of properties in British Columbia, afford excellent examples of work carried out on an extensive scale miles from a railway, or in comparatively inaccessible mountain regions.

Jan 1, 1928