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By Barbara A. Filas

The IFC goal is to promote private sector investment in developing countries which will reduce poverty and improve people?s lives. The developing country goal is to promote health, education and employment opportunities that improve their economies and their standard of living. The mining company goal is to Promote successful ?triple bottom line? mining projects that will grow shareholder equity

May 1, 2002

By V. Prostakova, M. Shevchenko

The copper smelting gas / slag / matte / metal / solids system with the Cu-Fe-Ca-Si-O-S major elements has been a long-term focus of the present overall research program using integrated experimental and modelling approach for the phase equilibria characterisation and development of a thermodynamic database. A systematic investigation of phase equilibria of slag systems in equilibrium with Cu metal is providing information for systems where copper coexists in slag with lead, zinc, and aluminium oxides as major components. Experimental studies involve high-temperature equilibration of synthetic samples; rapid quenching; and measurement of the compositions of equilibrium phases using electron probe X-ray microanalysis (EPMA). Particularly important feature of the present study a wide range of temperatures (660-1670°C) being characterised that reveals major inconsistencies in the existing thermodynamic description of the multicomponent system, and allows to establish the thermodynamic properties from phase equilibria in a reliable way. FactSage-based thermodynamic modelling is integrated with experimental research. Initial thermodynamic assessments are used to identify priorities for experiments, planned to provide specific data for thermodynamic optimisation. Significant improvement in the accuracy of the phase equilibria description is achieved, in particular in the PbO-Cu2O-SiO2, ZnO-Cu2O-SiO2, and Cu2O-CaO- Al2O3 systems in equilibrium with metallic Cu. INTRODUCTION Slags high in lead and copper are generated in primary metal production in the smelting of lead sulfide concentrates and in pyrometallurgical metal recycling systems. The compositions of these slags are varied due to increased fraction of recycled materials in the feed as well as introduction of previously unused chemical elements to modern technology. Therefore, their processing becomes chemically more complex; in that way they contain a large number of different metals. These slags form complex non-ideal solutions (with possible formation of several immiscible slags) that can coexist with stoichiometric solids, solid solutions, mattes and molten metal depending on the bulk composition and process conditions. Predicting the outcomes of smelting and refining processes is becoming increasingly difficult. To assist in the optimisation of these metallurgical processing operations, a comprehensive research program is underway to develop accurate thermodynamic databases for these non-ferrous process systems.

Jan 1, 2019

By Troy Boisjoli, Sean Hillacre, Matt Batty

Discovered in 2014, the Arrow Uranium Deposit has undergone rapid development through successive drilling programs informed by geostatistical drill hole spacing studies. An independent third-party geostatistical drill hole spacing study was completed by Clayton V. Deutsch Consultants Inc. in 2017, evaluating the uncertainty of thickness, grade, density, and areal limit of the Arrow Deposit to determine a drill hole spacing suitable for Indicated Mineral Resources. Indicated spacing was defined to be 24 to 32 metres (“m”) to be within 15% of predicted for a nominal quarterly production volume with a probabilistic tolerance between 75 and 90%. The study not only defined the Indicated Mineral Resource resultant from the 2016 drill program, but also provided drill hole targeting criteria for subsequent drill programs aiming to convert Inferred to Indicated Mineral Resources. A subsequent geostatistical drill hole spacing study on the Arrow Deposit was completed by Clayton V. Deutsch with Resource Modeling Solutions in December 2018 to define Measured Mineral Resource spacing in support of the 2019 drill campaign. The study resulted in a drill hole spacing of 9 to 17 m to be within 15% of predicted for monthly and quarterly production volumes using an accepted industry probabilistic tolerance of 90%.

Jan 1, 2020

By R. B. Stein

"Countercurrent decantation circuits(CCD) are often employed in hydrometallurgy to effect solids-liquid separation in combination with a barren solution wash to reduce losses of valuable solution component(s) from the tails. Bechtel Corporation uses its BEMSIM flowsheet-modelling PC computer program to simulate a CCD circuit where the ""dirty"" wash solution contains significant amounts of soluble components. An algorithm successfully models this condition and is simplified to a single expression when the wash solution is a ""clean"" solution containing no solubles. The CCD calculation module is compared to operating data from uranium and nickel-cobalt CCD circuits.IntroductionHydrometallurgical process schemes have often relied on countercurrent washing methods to reduce soluble losses of valuable product in the tails. Commonly used equipment to effect this operation is a CCD circuit of N thickeners in series, where a slurry is fed to thickener I and a wash solution to thickener N; clear pregnant solution overflows thickener I and washed tails exit as underflow from thickener N. CCD circuits of this type are typically employed when the solids tend to slime heavily and where a filter is not economic.A typical CCD circuit usually employs from two to five thickeners and can employ either a ""clean"" washing solution of, say, pure water or else the hydrometallurgical circuit may generate a ""dirty"" barren solution containing an appreciable amount of soluble component which may be advantageously returned to the process as CCD wash solution. Various authors have treated the case for clean washing solutions (Svarkovsky 1977, Merritt 1970). For the case of dirty wash solutions, an algorithm has been developed to enable efficient modelling by the BEMSIM computer program, because the need for an accurate method to calculate soluble losses is required when performing an economic trade-off analysis of the value of product lost in the tails as a function of the number of thickeners."

Jan 1, 1990

By Alex Matheson, Nick W. D. Massey, Peter T. Bobrowsky

Crowing pressures on aggregate resources include diminishing reserves, high transportation costs, sterilization and land use conflicts. In the absence of detailed resource knowledge for a particular region, aggregate resource potential maps provide the best "first approximation" regarding the surficial distribution of sand and gravel. The 1:50 000 scale Level Ill aggregate potential map integrates several important factors which influence the management of sand and gravel. Data used to generate this type of thematic map is readily available in most areas, fieldwork required is minimal, there is a logical quantitative evaluation of the data layers and integration is easily accomplished on a desktop PC-based platform. Also the aggregate potential map, with its focus on identifying areas of potential future aggregate exploitation as well as present inventory, provides a useful tool for the aggregate explorationist.

Jan 1, 2001

By Mario Gerards, Axel Wellendorf, Arulnesan Rajesh

"In times of increasing energy cost and global demand for improved machine technology, the optimization of industrial mineral processes in terms of efficiency and production cost is an important factor when choosing industrial equipment suppliers. Of course this applies for screening machines, feeders and distributers as well!Besides of the ability of a screening machine for being adjustable to changing requirements during the production process itself, it becomes more and more important to choose the correct screening machine type, peripheral equipment for arising screening tasks and to optimize the overall design of the screening machine starting at a very early stage.The different types of screening machines bring many advantages and disadvantages with them. The selection of the correct type of screening machine can improve the flow rate, energy, efficiency, yield, quality, output, availability and decrease the maintenance costs and structural steel work.The machine optimization has to be a consecutive process in which at any time results of simulation and “real-life measurement” are compared and the findings are implemented in machine development and design. As an example, it is possible to reduce machine weight and reinforce the steel structure of a screening machine at the same time, which enables the manufacturer to use smaller drives for the screen.This paper will present the methods ANSYS and 3D Solid Works used at RHEWUM GmbH for this way of optimizing machine design and construction and examples for results gained from this continuous improvement process."

Jan 1, 2016

By E. Burdukova

Rheological measurements have found a wide array of applications in mineral processing research. Rheological properties of mineral suspensions are highly dependent on the mineral surface properties as described by DLVO theory, and the relationship between these properties and inter-particle interactions is well established. In this paper, rheological properties of mineral suspensions are used to study the differences in behaviour of isotropic talc and anisotropic zirconia minerals as a function of varying properties of the suspension medium, such as pH and polymer dosage, specifically carboxymethyl cellulose (CMC). It was found that the rheological tests when carried out in parallel with electrophoretic or point of zero charge measurements, clearly reveal differences between behaviour of the suspensions of isotropic and anisotropic minerals. These differences are further accentuated with the addition of carboxymethyl cellulose (CMC).

Jan 1, 2006

By W G. Forbes

SOME 20 years ago, upon finishing second year at the University of Manitoba, I was faced with the choice of whether I wanted to be a geologist or a chemist. Accordingly, I sought out Professor Brownell, Head of the Department of Geology, to ask him what a geologist did. His reply contained the statement that following graduation one went out into the field in northern Canada for 5 to 15 years to reduce to practice what had been learned at university. To a young man, very socially conscious, even one year, let alone 5 to 10, in a small mining community sounded like being banished to a monastery in the Himalayas and thus I turned to chemistry. Moving to the present, last month I asked a geologist, and then a mining engineer, what does the fresh graduate in their field do these days? The reply was: usually serve an apprenticeship for an indeterminate period either underground or in the field learning the job.

Jan 1, 1965

By F. H. Edmunds

I N presenting this paper, the writer wishes to point out some of the difficulties and problems of geological work in that part of Saskatchewan in which outcrops are few. These problems are well known to all geologists who have made investigations in this region, but may not be so well known to those outside. A table of the strata as known in certain areas of Saskatchewan and the adjacent provinces is given, with a brief discussion of some of the formations and beds about which there is little knowledge due to their being deeply buried and not exposed in the region. Comment with regard to possible oil and gas structures is made and some features of the structures in the Battleford and Simpson districts are described. The writer wishes to make acknowledgment to members of the Geological Survey of Canada to whose work in Saskatchewan and the adjacent provinces reference is made, and to others who have made, or are making, valuable contributions to the stratigraphy of Saskatchewan. Mr. G. C. Webb has kindly furnished information regarding and materials taken from a well bored recently in the Paynton district. Special thanks are due to the Simpson Oil and Gas Company for permission to use much valuable information with regard to their wells and for the generous way in which the officials and staff co-operated with the writer. The opportunities the writer has had to visit many parts of the Province have been in connection with investigations for the Provincial Department of Natural Resources and through facilities provided by the Department of Soils of the University of Saskatchewan. To these Departments the writer accords his thanks. For the purposes of this discussion, Central Saskatchewan may be considered as that portion of the Province extending from Township 16, with Regina, Moose Jaw, and Swift Current situated on or near the southern boundary, to Township 48, with Prince Albert and Lloydminster on the northern boundary. This region includes territory underlain by Cretaceous sediments and excludes the southern portion of the Province, where Tertiary beds underlie the surface and are exposed to an extent sufficient to permit a measure of systematic mapping.

Jan 1, 1937

By M. Sengupta, A. A. de Gast

"With rapid deterioration in the urban environment caused by air pollution, the possibility of chemical reaction between dimension stone and the industrial waste gases present in the ambient atmosphere remains. The chemical reaction can cause expensive damage to building stone; it is essential that a stone evaluation for use in construction should assess the possibility of this type of decay. This paper endeavours to develop testing procedures for evaluating stone decay in polluted environments. Such tests can accompany other standard tests used in dimension- stone evaluation."

Jan 1, 1972

By R. D. Lawrence

"Comparable transaction analysis is the best known of the market approaches to valuation of exploration-stage mineral properties. The analysis of option and farm-in agreements can also provide useful guidance to valuators. While such approaches can be distorted by incomplete analysis, market-based methods are capable of providing consistent, credible results when carried out carefully with due consideration paid to all factors which buyers and sellers consider when dealing in the real market. IntroductionMineral properties without defined resources present one of the most challenging tasks to the mineral valuator. This paper will concentrate on market-based approaches to valuation of such properties. Other authors at MM2000 presented papers on cost and income approaches. Sorentino (2000) also provides a useful overview with some provacative commentary on methods.Market based-approaches are based on the principle of substitution and include such techniques as: comparable transaction analysis (sometimes referred to as sales comparison analysis); farm-in commitment (or option agreement) analysis; rules-of-thumb; and comparable market value analysis.Are there any valuation standards available to assist the valuator? In Canada there are none that apply to the valuation of mineral assets or securities. This problem is being addressed, at least in part, by the CIMVal Committee of the Canadian Institute of Mining, Metallurgy and Petroleum (CIM)1. Further, the recently established Canadian Association of Mineral Valuators will be giving consideration to the adoption of valuation standards."

Jan 1, 2002

By C. B. Webber, L. S. Diaz

"The paper presents the approach taken by Craigmont Mines to grinding circuit control. A detailed description is given of a fully automatic control system which bases its control actions on the continuous measurement of particle size in the cyclone overflow stream. The control system holds a specified particle size in the cyclone overflow, and grinds rod mi 11 ore feed at increased rates. The principles of operation of the system used for continuous measurement of particle size are described, end the improvements in mill throughput and copper recovery over several months of continuous operation are presented.INTRODUCTION Craigmont Mines Limited is located in the south-western interior region of the province of British Columbia, approximately 230 road miles north-east of Vancouver, and ten miles west of the town of Merritt. A moderate climate, good roads and service facilities provided by the Canadian Pacific Railway, Inland Natural Gas Company, and the B.C. Hydro and Power Authority, have provided a very favorable mine and plant site.The preliminary metallurgical design of the Craigmont mill was based on the test results of samples obtained from the original 2500' level drift during 1959. Pilot plant runs and other research testing for design pur¬poses were conducted at the Canadian Exploration Ltd. Laboratory, at Salmo, B.C. The design flowsheet was altered in progressive stages from 2,000 to 3,000, and finally 4,000 tons per day as the ore reserves became better defined. Construction work on the 2,400' level mill site commenced in late 1960. The official opening of Craigntnt Mines Limited took place on September 15, 1961, a little over two years from the time of the metallurgical assessment of the original ore samples.Mill throughput to date has varied widely both on a daily and a monthly basis, due to the varying hardness of the mine ores. The grindability af the ore appears to be related to the oxide iron content, which varies from lows of 9% to highs of 20%. Daily tonnage has ranged from 5,000 tons per day with 10% iron in the feed, to 6,000 tons per day with 20% iron feeds."

Jan 1, 1973

By John A. C. Fortescue

Details of the interactions between the environment and the growth of terrestrial plants may be complex and difficult to study. This paper focusses attention on some of these complexities by means of six examples, each of which provides information on an aspect of the interaction between the growth rate of plants and the chemistry of the environment. The relationships which exist between the information obtained from these examples and the concepts of "holism" and "transfer rate problems" are pointed out and the importance of long-term biog•eochemical studies in Canadian environments is stressed.

Jan 1, 1971

By R. L. Stanton

"The present contribution is complementary with a preceding one on the field association of the conform-able ""pyritic"" deposits. It considers the more important features of their mineralogical constitution and their microtextures, re-examines the present interpretations of these, and of-fer-some alternative explanations. The term ""pyritic"" for these de-posits is m many cases a misnomer, as two quite distinct ore types are inuolve. One is a banded pyritic sphalerite-galena-chalcopyrite ore (for which the term '•pyritic"" is in-deed quite suitable), while the other is non-banded and is composed essentially of pyrrhotite and chalcopyrite. In addition to these constitutional differences, each is distinctive in general appearance and texture. The occurrence of two such consistent but clearly distinguishable ore types is attributed -rather than to difference in source material and pressure-temperature conditions of deposition -to the contribution of similar source material to dissimilarly oxygenated environments of sedimentation. Textures in the banded ores generally thought to be indicative of replacement or of high-temperature exsolution are explained by slow, law-temperature segregation in situ during compaction, folding, and regional metamorphism."

Jan 1, 1960

By J. L. Blaylock

Normally, the hydraulic system and structures are considered to be unrelated items. In reality, the two cannot be separated because one affects and depends on the other to function properly. This paper explores the potential failure areas of hydraulic cylinders, and suggests possible methods to prevent failures from occurring. The use of high-strength low-alloy steel in frames is reviewed and the benefits discussed. Fabrication techniques and handling of material are noted in the hope that this knowledge will aid in the repair of frames in the field.

Jan 1, 1979

By Davis. B. R.

There are a number of hydrogen storage systems proposed for automotive applications. However, all of the current suggestions fall short of the DOE targets for storage density and volumetric density. The DOE has suggested that only through radically new ideas will a practical solution to hydrogen storage for automotive applications be realized. This paper provides some background in chemical hydrogen storage and discusses roadblocks to the implementation of some proposed technologies.

Jan 1, 2005

By R. Amelunxen

"The molybdenite associated with copper porphyry ores is generally treated in a flotation circuit consisting of a separation and a cleaning section. In the last few years column flotation cells have replaced the numerous counter-current stages that were previously used in the cleaning section. Despite this, little has been published regarding the number of column cleaning stages required. Therefore a Moly flotation database is assembled with the objective of verifying the existence of a common upgrading profile. This can then be used as a guide in the prediction of the number of stages required to achieve a given concentrate grade.INTRODUCTIONAlthough the first use of Column Flotation was on copper flotation products, the popularity and understanding of their operation was not really achieved until they were widely implemented in Moly circuits in early 1983. The use of columns in Moly plants has since left a legacy of information, both published and unpublished. The data collected since that time has been used primarily used to establish column operating parameters and to determine upgrading potential within the circuit.Byproduct Moly generally occurs with porphyritic copper ores in concentrations less than 0.1% MoS2. As such, piloting a new moly ore to produce, say 5 Kg/Hr MoS2, in a slurry approximately 1 Lt/min (at 10% solids), requires a moly plant feed of about 570 Kg/Hr, which translates to a mill feed rate of 200 to 800 Tonnes per day (depending whether you deal with Chilean or Canadian ores). Piloting Moly for any lower tonnage would reduce the accuracy of the testwork.Thus a need exists to collect operating data in order to establish the existence of process relationships that could be used for feasibility and design purposes.The object of this paper is to expose a preliminary relationship that could be used for the purposes described above and to apply the findings to a preliminary design of a moly cleaning circuit flowsheet."

Jan 1, 1990

By Mark Rebagliati, John Payne, Jim Oliver

Abstract-The Campo Morado precious-metal-bearing, volcanogenic massive sulfide deposits occur in a lower Cretaceous, bimodal, calc-alkaline volcanic sequence in a major northerly trending belt in the Guerrero Terrane in northeastern Guerrero, Mexico. During upper Cretaceous to Early Tertiary greenschist-facies regional metamorphism, the rocks were deformed strongly into a northeast-verging fold-and-thrust belt. Three later stages of weak deformation were dominated, respectively, by kink folds, broad warps, and extensional faults. Most deposits occur in the upper part of a sequence of felsic flows and heterolithic volcanoclastic rocks or at its contact with overlying chert and argillite-sandstone. The Reforma and El Rey massive sulfide deposits are on the overturned limb of a major, thrusted anticline, and the Naranjo and El Largo massive sulfide deposits are to the south on the upright limb of the same major fold. The La Lucha and San Rafael massive sulfide occurrences are in an upper plate to the southwest which was thrusted over the plate containing the Naranjo and El Largo deposits. In several of the deposits, Au, Ag, Zn, and Pb are concentrated near the stratigraphic top, and Cu is concentrated near the stratigraphic base. Major minerals are pyrite, quartz, ankerite, sphalerite, chalcopyrite, and galena. Minor minerals are tennantite-freibergite, arsenopyrite, and pyrrhotite. Gold and Ag occur in argentian gold, and Ag also occurs in tennantite-freibergite. The cumulative inferred resource of massive sulfide for the Reforma, Naranjo, El Rey, and El Largo deposits exceeds 30 Mt, with the latter two deposits incompletely delineated. Underlying pyrite-quartz stockwork zones contain chalcopyrite, chlorite, and sphalerite. Hydrothermal alteration minerals in the stratigraphic footwall are pyrite, quartz, chlorite, ferroan dolomite, and ankerite. In the stratigraphic hangingwall, hydrothermal alteration minerals are sericite, calcite-dolomite, and lesser clay minerals and quartz. The deposits belong to a low-sulfidation, volcanogenic massive sulfide system formed in a subaqueous environment, and are of the bimodal, siliciclastic type.

Jan 1, 1997

By Mark Rebagliati, John Payne, Jim Oliver

The Campo Morado precious-metal-bearing, volcanogenic massive sul?de deposits occurin a lower Cretaceous, bimodal, calc-alkaline volcanic sequence in a major northerly trending belt inthe Guerrero Terrane in northeastern Guerrero, Mexico. During upper Cretaceous to Early Tertiary greenschist-facies regional metamorphism, the rocks were deformed strongly into a northeast-verging fold-and-thrust belt. Three later stages of weak deformation were dominated, respectively, by kink folds, broad warps, and extensional faults. Most deposits occur in the upper part of a sequence of felsic ?ows and heterolithic volcanoclastic rocks or at its contact with overlying chert and argillite-sand-stone. The Reforma and El Rey massive sul?de deposits are on the overturned limb of a major, thrusted anticline, and the Naranjo and El Largo massive sul?de deposits are to the south on the upright limb of the same major fold. The La Lucha and San Rafael massive sul?de occurrences are in an upper plate to the southwest which was thrusted over the plate containing the Naranjo and El Largo deposits. In several of the deposits, Au, Ag, Zn, and Pb are concentrated near the stratigraphic top, andCu is concentrated near the stratigraphic base. Major minerals are pyrite, quartz, ankerite, sphalerite,chalcopyrite, and galena. Minor minerals are tennantite-freibergite, arsenopyrite, and pyrrhotite. Goldand Ag occur in argentian gold, and Ag also occurs in tennantite-freibergite. The cumulative inferred resource of massive sul?de for the Reforma, Naranjo, El Rey, and El Largo deposits exceeds 30 Mt, with the latter two deposits incompletely delineated. Underlying pyrite-quartz stockwork zones contain chalcopyrite, chlorite, and sphalerite. Hydrothermal alteration minerals in the stratigraphic foot-wall are pyrite, quartz, chlorite, ferroan dolomite, and ankerite. In the stratigraphic hangingwall, hydrothermal alteration minerals are sericite, calcite-dolomite, and lesser clay minerals and quartz. The deposits belong to a low-sul?dation, volcanogenic massive sul?de system formed in a subaqueous environment, and are of the bimodal, siliciclastic type.

Jan 1, 1997

By O. Kodym

The paper has focused on possibilities of interconnecting information sources concerning monitoring & control of mining industry technical processes (TP), and the related safety hazards. The key issue is the comprehensiveness of the information presented to users. Information can be presented by virtual reality means, when the seemingly true presentation of the production process scene along with user friendly presentation of related information is available. The user in its role of a process supervisor is not only a mere scene observer but, thanks to the interactive functions of virtual environment, he participates in the scene of his control. As such his control and management abilities increase because he can absorb, more easily understand and asses the information provided.

Aug 1, 2013