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By María Eugenia Castro, Silvia Galasso, Jorge Duca, Claudia Osuna, Ernesto Esparza

"We present a procedure for treatment of non-active solutions equivalent to the solutions obtained from dissolution of ionic exchange resins used in purification of a nuclear reactor primary cooling system containing Co, Ni, Cs and its isotropic varieties as main radioactivity source. Finally it is immobilized into a ferritic matrix by calcination which avoids its future leaching into environment.In order to achieve the objective of this treatment, a bivalent and a trivalent iron salt is added to the solution. Then, either a base or an acid is added, depending on the initial pH of the treated solution, with a Cs precipitating additive in order to reduce Co and Cs by precipitation, flocculation and adsorption. Controlling the amount of precipitating reactives it is possible to modify the activity/volume rate becoming a medium into a low radioactivity waste.The leaching test result applied over the ferritic sample is lower than the minimum limit established by law. Therefore, it can be kept safely in a interim storage."

Jan 1, 2008

By P Taskinen, D Lindberg

The increase in metals demand in the electrifying globe means significant growth in the smelting of copper, nickel, zinc, and lead, produced from primary sulfide sources or using sulfide mattes as the intermediates of the process chains. This means that leaner and complex mineral deposits will be evaluated as ores and are in the future traded in the commodity market for smelting and refining to pure metals. An important issue in the trend is the technology metals, like antimony, tellurium, and gallium, which exist as trace elements in sulfide ores and form no ores of their own. Their recovery becomes important in the coming decades as will be the case with growing slag amounts without use in other industries. The key is to produce environmentally acceptable slags in the smelting operations. It sets new boundary conditions to the treatment of flue dusts. This means that all material streams of smelting and refining must be re-evaluated for the deportments of the main and minority metals. In copper smelting, the recoveries of precious metals are today important for the feasibility of the custom smelters but due to low prices of many minority metals they are discarded in slag landfills. It is one of the emerging issues also in the secondary copper smelting today and once the demand grows, the same question will be faced also in the mining-beneficiation-smelting-refining chain of the primary production of nickel, zinc, and lead. The distributions of many technology metals in the copper and nickel smelting have been recently studied using methods where the chemically bound trace elements in the slag and its phases at the smelting conditions have been studied. Thus, the key data about options for process modifications and additional processing steps are piling up. Short processing routes in the metals smelting and refining are attractive due to their simplicity. At the same time, complexity of many raw materials challenges the fluxing at high oxygen partial pressures in low silica slags with high metal concentrations. The compromise between high primary recovery and safe operation is a demanding task in conditions where slag foaming outside the processing window is evident. The increase in the demand of pure nickel is challenging the raw material basis where low-grade sulfide ores are soon smelted along with nickel laterites to matte. It is a demanding task at high MgO concentrations. The low solubility of MgO in iron silicate slags requires new fluxing strategies and new smelting end points for the operation at reasonable temperatures; the direct nickel matte smelting in one-matte mode may be an option.

Aug 21, 2024

By Chris Harnan

This paper describes the geology of three European cities and outlines how the geology has lead to the development of specific foundation construction techniques. Comparative tables of techniques commonly employed are given in Section 5. It can be seen that despite the presence of the 'single market', techniques still have wide diversity despite some similarities in geotechnical conditions.

Jan 1, 2000

By Rudolph P. Frizzi

Quality control is essential for augered cast-in-place (ACIP) piles (also known as continuous flight auger (CFA) piles outside the United States) and drilled displacement (DD) piles since the pile is constructed below the ground surface out of the direct sight of the personnel constructing and inspecting the pile. ACIP piles are being successfully constructed to support high-rise structures, hospitals, arenas and stadiums, mass transit systems, and power and industrial facilities. The use of DD pile technology is also gaining ground in the United States, typically utilizing proprietary systems such as Omega (currently utilized by Richard Goettle Inc., and LG Barcus and Sons, Inc.), Berkel, and DeWal (currently utilized by Morris-Shea). Different types of ACIP/DD pile installation equipment are shown in Figures 1 and 2. ACIP piles are installed into granular and cohesive soils, and soft rock to lengths currently approaching 130 ft (39.5 m), with diameters up to 24 to 36 inches (610 to 915 mm), and sustaining design loads approaching 900 kips (4000 kN). Current DD pile installation equipment in the United States is capable of installing up to 79-ft-long (24 m) piles with diameters ranging from 12 to 18 inches (305 mm to 460 mm).

Jan 1, 2003

By J. Keith Haddock

"Introduction The Luscar company, Forestburg Collieries Ltd., operates the Diplomat Mine located 14 km south of Forestburg, Alberta. Production is now at a declining rate from the 1 million tonnes achieved in 1978 as the reserves are being depleted. Three pits are operated at this prairie strip mine utilizing draglines and stripping shovels to uncover the coal. The coal is hauled to a tipple on site for shipment by rail or highway vehicles or is hauled directly to the adjacent Battle River Generating Station. Geology The mine is currently extracting the Battle River seam on the north side of the Battle River. This is the lower-most seam in the Horseshoe Canyon Formation and is the only one present in the area, the upper seams having been eroded by glaciation. The seam lies generally flat and varies from 2.0 to 5.0 metres thick. It lies under glacial till overburden varying in depth from 5.0 to 12.0 metres. The mineable coal extends from the side of the Battle River valley where it outcrops, to approximately 2.5 kilometres to the north. The mine is spread out over a distance of 8.0 kilometres in an east-west direction. Reserves and Coal Quality After over 30 years of mining at Diplomat, there are now less than 1 million tonnes of mineable reserves remaining on the property. With the commencement of coal production from the Paintearth Mine in 1981, supply to the Battle River Generating Station, formerly Diplomat's biggest customer, is being transferred to Paintearth. Rail shipments and domestic supply will continue until reserves are depleted. The coal has the following specifications:"

Jan 1, 1985

By Thomas Jenning, C. M. Keithly

"INTRODUCTION This report is one of a series. 4. 5. 6/ concerned with presenting historical development, and operating data on secondary-recovery projects in various States to stimulate interest in sound secondary-recovery programs. Preceding reports in this series have dealt exclusively with descriptions of and results obtained by water flooding in three states, but no recent publication of comparable purpose describes gas-injection 7/ practices. The authors intend to present material relevant to the development and operation of gas-injection projects in Illinois, with particular emphasis on those producing from oil-bearing horizons that had been depleted to a point near the economic limit of operation by past oil-recovery methods.Most operators realize that the energy expended on the movement of fluids through gas-expansion- or gas-cap-type oil reservoirs to producing wells must be supplemented to attain maximum recovery of the oil present. Under favorable conditions, many operators choose to maintain oil-propulsive forces at or near their original magnitude by injecting extraneous fluids into a reservoir or recycling produced fluids early in the life of a field. More common, and less desirable, is the practice of replenishing these forces after primary producing methods become unprofitable. The lattes practice has been adopted in many stripper fields in Illinois and most of the oil-producing States during the last 40 years, but other old oil fields, and oil properties within those fields which were partly exploited by secondary--recovery methods, also may offer favorable opportunity for further development. To encourage and, aid operators in the development of gas-injection projects in the old oil fields of the United States, four projects have been described in detail in this report."

Nov 1, 1944

By Éric Létoumeau, Julie Fournier, Sylvain Caron, Yves Breau, Martin Plante, Dominique Girard, Luc Tardif, François Robichaud

"Since 1999, COREM (formerly the Centre de Recherche Minérale) has conducted and coordinated research and development activities for a consortium of mining companies that uses the benefits and advantages of collaborative pre-competitive research. In particular, COREM’s “In Situ Optimization Group” is involved in the development and implementation of modem information technologies related to process optimization and control.The POP Project was launched in order to increase and consolidate the use of such technologies applied to mineralurgical and metallurgical processes. To ensure a successful transfer to the industry, there are a number of essential activities that have to be undertaken. These activities have been identified by COREM’s members and are grouped into three main modules:- R&D Module: research and development in universities and research centres;-Technology Transfer Module: integration of new tools into the POP Software, industrial applications and technical support;- Training Module: education of new engineers in universities and continuing education of plant personnel through on-site workshops.This paper outlines the opportunities that led to the definition of the POP Project, presents its main objectives and describes its main modules. The main features of the POP Software are outlined, the first applications at COREM’s member plants are presented and, finally, future developments are discussed."

Jan 1, 2002

By B Kretschmer, G Bartel, B de Villiers, W Watt

"The Nyrstar Port Pirie Smelter, located on the eastern shore of the Upper Spencer Gulf in South Australia 230km north of Adelaide, began operation in 1889 to process lead concentrate from the Broken Hill lead and silver mines. The site still operates an updraft sinter machine, commissioned in 1955, with the product fed into a blast furnace. While sinter plant technology has changed and improved since 1955, development has reached the stage where further enhancements are not possible or economic. High purity lead concentrates command lower margins and for the smelter to remain economically viable a wider range of higher value materials must be treated. The current flowsheet cannot meet this demand. Additionally, community blood lead levels particularly in children below four years of age, are a critical indicator used to measure the site’s environmental performance. The smelter’s environmental licence to operate is dependent on meeting future community and regulatory expectations. To achieve this a major step change in the emission performance of the smelter is required. Since 2008 pre-feasibility work has been undertaken to develop a new flowsheet and business model to allow Port Pirie to operate sustainably into the future. The main requirements were for the smelter to reduce lead and sulfur dioxide emissions that impact on the local environment and community to meet current and future environmental expectations, as well as dramatically reducing current feed constraints and change the business case from a marginal business to a sustainable profitable business. After reviewing all practical options a decision was made to replace the sinter plant with an Outotec Top Submerged Lance (TSL) furnace. This paper describes how the new furnace technology was selected and how it will be integrated into the present flowsheet; the unique funding arrangements that are in place to deliver the redeveloped site; and future opportunities that are associated with the implementation of the new flowsheet. CITATION: De Villiers, B, Bartel, G, Watt, W and Kretschmer, B, 2015. Nyrstar Port Pirie redevelopment, in Proceedings MetPlant 2015, pp 325–337 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 7, 2015

By J. Bruce Clemmer, M. F. Williams, B. H. Clemmons, Carl Rampacek, R. H. Stacy

"INTRODUCTION This report is the first of several dealing with the application of flotation methods for beneficiating the calcareous and siliceous red iron ores and ferruginous sandstones of the Birmingham district. The flotation study was part of a general investigation of the concentratability of various iron ores of Alabama and other Southeastern States undertaken by the Southern Experiment Station of the Bureau of Mines, United States Department of the Interior, in cooperation with the University of Alabama, Tuscaloosa, Ala.Batch testing and pilot-plant flotation testing of the calcareous red ores of the Birmingham district have been in progress for several years, and although some phases of the study are not yet completed, enough data are available to indicate that many of the ores will yield marketable-grade concentrates with good recovery.The first flotation tests on the calcareous red ores employing conventional methods either the iron oxides or the siliceous gangue materials failed to give the desired results. The inferior separations obtained or prohibitive reagent requirements made the methods unattractive. Other more effective flotation methods were sought. A laboratory study of various reagents was undertaken. It resulted in the development of two attractive methods embracing anionic flotation of the activated siliceous gangue from the retarded iron oxides. The methods were similar in that fatty acid or soap-collecting agents were employed in strongly alkaline pulps to float the naturally activated quartz from the iron-ore pulps. The methods differed, however, in the addition agent employed to retard the hematite or hematite and calcite. By proper choice and quantity of the addition agent, the calcite could be floated with the quartz or retarded with the hematite as desired. Ability to recover or reject the calcite gives added flexibility to the separation. Although the methods have their limitations and cannot be considered ""cure-alls,"" they have given encouraging results on a number of calcareous red ores that heretofore proved difficult to concentrate by conventional flotation procedures."

Mar 1, 1945

By K. E. Waters, J. E. Nesset, F. Rosenblum, R. Langlois, J. A. Finch

"Some sulphide mineral mixtures when exposed to air and a warm and humid environment can exhibit a self-generating temperature rise, referred to as self-heating or spontaneous heating. The observed self-heating derives from the oxidation reactions of the active sulphides. In previous publications by the authors, it was proposed that the self-heating of sulphides proceed in three distinct stages; namely, Stage A, Stage B and Stage C. In Stage A (<100OC) the sulphides, in the presence of moisture are oxidized, generating heat through a series of sequential reactions and forming elemental sulphur as one of the products. In Stage B (>100OC) the elemental sulphur produced in Stage A is further oxidized to generate additional heat and SO2. Stage C (>~380OC), sometimes referred to as thermal runaway or roasting, is not addressed in this paper. This communication focuses on the type and role of elemental sulphur found in Stages A and B, and the sequence of reactions that is occurring in Stage A. The sequence is divided into two phases, the first based on galvanic interaction between the sulphide minerals that generates an acidic environment but little heat, and the second involving the production of H2S which rapidly oxidizes to produce heat and elemental sulphur. To date, data suggest that the primary oxidation product formed in Stage A is the stable orthorhombic a-S8 form of elemental sulphur. Above 96OC the a-S8 transforms to a monoclinic ß-S8 structure which is less stable and will readily oxidize to generate heat and SO2. Above 159OC a proportion of the ß-S8 sulphur will transition to a polymeric Sµ form of sulphur which can readily volatilize. INTRODUCTION Some particulate and granular materials, when exposed to appropriate atmospheric and physical conditions, can exhibit a self-induced temperature rise resulting from accumulated heat due to internal exothermic oxidation reactions. This phenomenon is commonly referred to as self-heating or spontaneous heating. Under favorable physical and environmental conditions, these reactions can elevate the temperature of a given material from ambient to the point of auto-ignition. Self-heating behaviour should not be equated to pyrophoric behaviour which describes a group of materials (e.g. certain finely powdered metals) that will ignite spontaneously in air below 55OC. There are numerous materials such as coals, hay, forestry wood products, food products to name a few that can exhibit self-heating behaviour. This publication continues the focus of the authors on the self-heating of sulphide mineral mixtures. Many of the metals of commercial use found in nature are in the form of these sulphides which must be mined, crushed, ground and concentrated prior to smelting or hydrometallurgical processing in order to produce primary metal. The issues of sulphide self-heating therefore pertain to the mining and processing of metals."

Jan 1, 2018

In March 1990, Heritage Mining conducted a 2000 line km high resolution aeromagnetic survey of all its prospects in the Coromandel Peninsula. One of the areas covered was the Onemana Peninsula, situated about 5 km north of Whangamata. Details of location and geology are given by Robson and Stevens (this volume). &nbsp; The detailed helicopter-borne magnetic and radiometric survey over the Onemana area consisted of 163 line kmÆs of flying, and was carried out in order to assist in the definition of hydrothermal alteration and pre- or post- mineralisation structures. The line spacing chosen was 100 m, flown east-west, with a mean sensor terrain clearance of 80 m. Tie lines were flown north-south every kilometre for levelling purposes. The sensor was a Geoinstruments G-813 proton precession magnetometer in a towed bird, with data recorded using a Geoinstruments G-2000 acquisition system. &nbsp; The Onemana alteration system is at the northern end of a major north-north east trending structural corridor defined by regional aeromagnetic surveys performed by AMOCO in 1980 (Rabone, 1991). T his structure hosts a number of other extinct hydrothermal systems including Karangahake and Golden Cross. In the Onemana contour plot the predominant north-northeast structures form the boundaries of a large area of subdued magnetism in the southern part of the surveyed area that is caused by intense hydrothermal alteration. This area is about 3.5 km long by 1 km or more wide and contains outcropping sinters and hydrothermal eruption breccias, as described in Robson and Stevens. A number of other structures transect this alteration zone, with strike directions ranging from northwest to north. A northwest feature notably truncates the zone to the south, while the northern end seems to be simi1arly bounded; however as data coverage ends at the coast, this feature is less conclusive.&nbsp; &nbsp; Two distinctive types of strongly magnetic rock were discernible the contoured data. The strong negative magnetic anomalies the north and west are caused by fresh negatively magnetised rhyolites. This was confirmed by ground follow-up work that showed the rocks to be fresh biotite rhyolites with high magnetic susceptibilities.

Jan 1, 1991

By Homer S. Frankhouser

Materials may be dredged, processed, stored and loaded for shipment at a single site in water depths ranging from 250 to 1200 ft. Solution mining may also be accomplished in deep sea situations. And, open air subsea mines with direct surface access may be developed and worked under the ocean floor. These concepts for deep sea mining are the results of extensive testing of individual components of the proposed systems by Dravo Ocean Structures, Inc., a subsidiary of Dravo Corp. A basic structure in these systems is the articulated platform. The platform consists of a gravity- type base and a buoyant cylindrical column which is constructed at an onshore location, towed to the offshore site and installed in a matter of days without use of heavy equipment. The base is also buoyant for towing purposes. This allows for gradual flooding to the point of negative buoyancy for positioning and anchoring to the ocean floor.

Jan 1, 1971

By D. H. Trollope

In engineering in general, close agreement between theoretical predictions and structural performance is rare—this is particularly true in rock slopes. Since the complexity of natural arrangements makes exact theoretical solutions of associated structural problems almost impossible, the role of theory should be that of developing guides or markers to which observations and experience can be related. The author in this paper has outlined the results of a theoretical study of highly idealized models which represent both granular materials and jointed rock. Some important practical considerations result—especially in regard to horizontal stresses—when theory is compared with full-scale experience. In the field of engineering activity, specific examples of close agreement between theoretical prediction and structural performance are rare. Particularly is this so for the case of rock slopes, where, owing to the complexity of the natural arrangements, it is quixotic to expect exact theoretical solutions to the associated structural problems. The role of theory is rather that of developing signposts or guide rails to which observations and experience can be related. It is with this in mind that the present paper has been prepared; the author&apos;s aim has been to set out briefly the results of a theoretical study of highly idealized models which represent both granular materials and jointed rock. Despite the idealization of the problem, it will be seen that the theoretical conclusions are in accord with full-scale experience, particularly as far as horizontal stresses are concerned, and they point to some important practical considerations. CLASSIFICATION OF ROCK SLOPES At the risk of over-simplification, an attempt has been made to classify the problem of rock slopes into three broad categories with respect to internal stress systems. These are illustrated in Fig. 1. It is tacitly assumed in this classification that the strength of individual particles is very much greater than the interparticle strength whether the particles are the crystals of an igneous rock (Case I) or the blocks of Cases 2 and 3. The Homogeneous Monolith: This case is representative of uniform unjointed rock. Under relatively low stress conditions the internal stress system may approximate to that of an elastic body as given by Terzaghi.&apos; It is more usual, however, for overall stability, to consider the material as a rigid plastic which yields in shear when S =C + c tan 4> where S is the shear yield stress, o is the normal stress on the surface of failure, and C and d are empirical constants according to the Mohr-Coulomb criterion of failure. Sokolovsky has recently developed, for the first time, a series of mathematical solutions to problems involvinga C, mass subject to self-weight. He demonstrates that for such a case a semi-arch (Fig. 2) is stable. A corollary of this argument is that for a true C, d material a curved overhanging slope is possible and such an observation may well aid field identification of these materials. The shape of the curved slope face is however directly dependent on the C-value, and from the long-term point of view this is a most difficult value to establish with any degree of confidence. It is customary to measure C and 0 in some form of shear test—usually a triaxial compression test—on core specimens sampled from the rock, and as far as the author is aware the present case is the only one in which, as far as overall stability is concerned, such tests are

Jan 1, 1961

By W. G. Freeman

It is unlikely, as In the past, improvement in truck efficiency and capacity can fully offset the effects of inflation, fuel costs/shortages and ever increasing haul distances. There-fore, investigations of haulage systems less sensitive to these problems are warranted. Thus, this U.S.B.M. contract research study on alternative continuous haulage systems was prepared. This study identifies the physical, economic and technological parameters in the application of continuous haulage systems with special attention to under pit slope conveyors and skip hoisting systems. The evaluation data was gathered from extensive literature searches. European/North American mine visits, and industry comments. The study concludes that continuous underground haulage is a viable method within the proper geometric configuration.

Jan 1, 1978

By C. N. Savage

An industrial minerals review involves an attempt to assemble field and statistical data which are obscure, elusive and incomplete. Often, when me statistical data are available, combining or lumping of commodity values conceals the value of specific items. Personal knowledge of the minerals known to occur in the area of concern, combined with whatever available published data may be compiled, together with careful use of several extrapolation methods, may yield an acceptable summary review of the industry. However, it is particularly hazardous to speculate on future trends and economic aspects because of the many unpredictable variables which may affect the industrial minerals business. Among these variables are the effects of diverse geological conditions, the impact of technological changes (including new uses for minerals not formerly considered industrial types), changing socio-economic factors (including growing environmental controversy), use of substitutes and even recycling of some of the industrial minerals (for example, building materials, lime, etc.). My main objectives are to reveal, as accurately as I can, the state of the in¬dustrial minerals situation, and the effects of possible future developments on this industry in Idaho. Where the words...industrial-tyke minerals, .are used in this discussion, reference is made to selected metallic and nonmetallic minerals and related materials, as well as rock (Table I). Industrial minerals known to be present in Idaho may be listed under general use categories as in Table 1. Some of these commodities are being marketed, have been marketed in the past, or occur in potentially marketable quantities. Mineral fuels are neither mentioned, nor are they considered important in Idaho. Based upon our present knowledge and lack of known, economically valuable occurrences of these commodities, they are considered insignificant (Idaho Bur. Mines and Geology, 1964). Information used for this study is from several sources. Most of the statisti¬cal information should be credited to the U.S. Bureau of Mines Minerals Yearbooks,

Jan 1, 1971

Using mines in Canada, Boart Longyear, a leading provider of drilling services and products, has put its Stage 3 Coring Bit to the test and each time the bit has passed the test with great success. After more than a year in the field at a major mine operation in Sudbury, Canada, the Stage3 coring bit broke life records to become recognized as the most productive design in the industry. In addition to the proven advantage seen in regular bit life increases of as much as 300 percent in some cases, the design is quickly being recognized for its cost-saving operational impact. In Sudbury, the mine operation realized actual cash savings of more than C$45,000 within an eight-month period by making the switch to Stage3 bits. For years, the Sudbury Basin team has relied on the Alpha Extended Crown bit with the Express Waterway geometry option, ordering approximately 500 units per year. This 07 COM ECEX configuration performed well in medium-hard, non-abrasive to ultra-hard, non-abrasive formations with an average bit life of 150 m (490 ft). While satisfied with the performance of the Alpha Ex-tended Crown, the team agreed to put the new Alpha Stage3 to the test. Boart Longyear?s field engineers supplied five drill sites with Alpha Stage3 bits in a 07 COM configuration. After thoroughly testing the Stage3, the results were clear. Even with the well-known performance and versatility offered by the previously preferred configuration, the Stage3 set a new standard of bit performance. The new bit maintained its cutting edge for up to three times longer than the Alpha Extended Crown, a significant performance increase when compared to the 07 COM ECEX.

Jan 1, 2009

By Unknown

Blast Site Security Involves: * Clearing the area * Controlling Access * Warning Signals

Jan 1, 2003

By Richard E. Bischke

Computer assisted finite element model analysis, originally developed to study stress distributions in aircraft, has been modified into a versatile mining program, that can be used to assist the engineer with predictions of mine subsidence. International Exploration, Inc. has developed an in-house finite element model program which incorporates a multitude of factors influencing mine subsidence such as mine design, physical rock properties, structure, faults, joints and topography. Finite element analysis of a mine model can mathematically determine the magnitude and direction of the principal stresses within each of the elements forming the model. By comparing the calculated in-situ stresses to the actual rock strengths, high risk regions within a mine can be identified. These potentially unstable regions of the mine can be allowed to fail within the model and the resultant stress redistribution and element movement calculated. Thus, the effects of the mine collapse at the surface can be predicted for the purpose of determining the potential damage, if any, that could occur to surface structures from deep mine failure. Stabilization materials can also be mathematically inserted into the model to design and analyze the effectiveness of subsidence prevention programs. Two examples are presented of the finite element program being used to predict mine subsidence at substantially different geologic and mining provinces in Pennsylvania.

Jan 1, 1984

By H. Powell

"This paper discusses how elemental analysis of conveyed bulk flows in real time using PGNAA (Prompt Gamma Neutron Activation Analysis) technology has resulted in significant improvements in advancing plant control in mineral processing operations. PGNAA through belt, full stream, continuous, multi-elemental, real time analysis technology is explained. Capabilities and limitations in plant operating environments are discussed including comparison with other real time, on-line technologies through review of published information available for on-conveyor minerals applications. Case studies include an iron ore and copper-gold company, both of which consider the technology an essential component in advanced plant control necessary in new process flow sheet designs, rather than an optimisation tool.INTRODUCTION Process operators rely on supply of a reasonable ore quality and consistency from the mine. Unfortunately neither the mining nor process operators have much control over the ore quality once it has been put into the crusher. Grade control typically stops once the material is designated as ore and the process plant operator needs to process it irrespective of quality. Plant control is most effective when technologies measure process streams directly and preferably in real time. Measuring sampling streams that are not representative of the primary flow will result in incorrect plant control decisions. Sampling coarse conveyed flows is expensive and impractical at many operations, however, this does not mean those flows cannot be measured. Investigations to find techniques suitable for real time elemental analysis have focussed on the application of known laboratory techniques to process streams. For conveyed applications, development of neutron irradiation techniques were most promising and early studies indicated potential success for bauxite measurement (Beurton et al, 1995). Tran & Evans (2001) concluded there was no equivalent technology to PGNAA in terms of material penetration power and that the technology was eminently suitable for basic industries such as cement. Nelson and Riddle (2003) evaluated PGNAA for possible use in the phosphate industry by using a unit installed in a cement plant to test performance on phosphate samples and ultimately recommended its use for further characterisation of the mine’s various ore types to improve stockpile allocation and grade control"

Jan 1, 2014

By McHenry Mosier

Mechanical loading, adopted long ago in open-pit, coal, and non-metal mines, was not used extensively in underground metal mines until the World War. In less than a decade it became standard practice in underground work in many mining districts. In 1924 the Missouri School of Mines and Metallurgy, in cooperation with the Federal Bureau of Mines, published a bulletin entitled "Mechanical Underground Loading in Metal Mines," which was prepared by Charles E. van Barneveld, mining engineer, Bureau of Mines.

Jan 1, 1940