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By Donald H. McLaughlin

ZEST in the search for new supplies of metallic ores and petroleum is difficult to maintain with stocks of raw materials accumulating and with over- production rightly or wrongly blamed for most of our industrial troubles. Enthusiasm over new methods of prospecting has consequently diminished and exploration programs in many fields have been drastically cur- tailed. Very naturally the effects have been felt with particular keeness in highly specialized phases of the work, such as geophysical prospecting, for the feverish scramble for new areas in which to drill beneath magnetic or electrical anomalies has abated, and there is even a lull in the firing in the battle over salt domes on the Gulf Coast. It is unquestionably an unhappy time for many of the organizations dependent on this work, but in certain respects the situation may be beneficial in correcting unsound practices that .have grown up through the necessity for haste and for quick decisions. With the restriction of the field to the more competent workers by the harsh rule of survival of the fittest, a general improvement, not only in technique but in business methods, can be expected which may go far in restoring public confidence. Geophysical prospecting in the short period that it has been utilized in North America, has suffered severely both from over-popularity and from excessive abuse. The former evil now

Jan 1, 1931

By N. L. ALISON

MUCH has been published on the general subject of metal mine ventilation but, so far as I can discover, few specific data on selection of fan equipment to meet the requirements of a given mine ventilation problem are available. This article is intended to point out some of the more important considerations which influence the selection of such equipment. It will be assumed that the mine operator is able to determine the quantity of air which is necessary in the various parts of his mine to produce the required results and the pressure in inches water gage needed to circulate this quantity of air through the mine. There may be instances in which this assumption is not justified, but the fact remains that, with proper engineering talent, these data can be approximated sufficiently close for practical purposes.

Jan 1, 1930

By Charles Will Wright

Brief descriptions of the occurrence of the various deposits of strategic minerals then known in South America are published in "The Mineral Deposits of South America," by B. L. Miller and J. T. Singewald, 1919; in "Ores and Industry in South America," by H. F. Bain and T. T. Read, 1934; and in many publications on the individual countries. To give a gen.era1 idea of the situation today and possibilities for future output of strategic minerals in several of the countries, the following notes are offered. All tonnages are in metric units.

Jan 1, 1940

By Irving Hartmann, H. P. Greenwald

READERS of this journal are familiar with the danger of coal-dust explosions in mines and with recommended means for preventing them. The subject was treated in a paper by R. R. Sayers in the January 1943 issue, as well as in several previous articles. Similarly the danger of dust explosions is generally recognized in the handling of grain dust, flour, starch, sugar, and other carbonaceous products. However, until recently, few people realized that an analogous, real explosion hazard exists wherever dust suspensions of certain finely divided metal powders are formed. This lack of knowledge was in part due to the fact that until a few years ago only a small number of metal powders, such as aluminum, magnesium, zinc, iron, and tungsten, were produced, in comparatively small volume, and partly because information on the explosibility of metal powders was lacking.

Jan 1, 1945

By Augustus Locke

I WISH to urge on this Committee the task of evaluating mining geology. -My motive is as follows: It, is a. duty of the Institute from time to5 time, to establish the social perspective of the professions grouped within it, not simply to promote their use, but to determine with engineering definiteness their true powers and functions. This becomes the delegated duty, therefore, of this committee in respect to geology. Be- cause my own subject is mining, I shall confine my remarks to mining geology. But I believe that the evaluation should be made to include all of that geology termed economic. The perspective for such evaluation is shown in the nature of the public support given to geology. The federal Geological Survey, the leading organization on the economic side, is actuated by the zeal of a small group of devoted professionals who consider its work valuable, ' It proceeds, however, on a starvation ration of appropriations, and that implies that neither the corporations, the voters nor the vote getters consider it important. Altogether, in' the public consciousness, geology is negligible. That, at the same moment, .the profession should act with full confidence, while everyone else should act' with opposite motives, is not fitting. For us, as a committee, to remain incurious regarding such a disparity of beliefs is quite impossible.

Jan 1, 1931

By S. H. Ash

IN no part of the world other than a small area in Pennsylvania is anthracite mining an industry of major magnitude. As the deposits of anthracite in the United States are limited virtually to Pennsylvania, the difficulties of this industry have been commonly considered a state rather than a national problem. However, there is also national interest in the conservation and wise utilization of all the country's fuel resources and in the control of interstate waterways. The anthracite industry is confronted with a serious problem of water accumulation in many of the mines, a problem that must be solved in the near future if progressively higher mining costs are to be avoided. It cannot be solved by the operating companies without state or Federal aid, or both, owing to the magnitude of the work required, the diversity of interests of the coal and surface ownerships, the hazard to the whole mining community, and interests affected outside the mining region. 'The costs of abating the ever-increasing surface seepage to mine workings and of handling this seepage once it has occurred are beyond the eco¬nomic resources of the operating managements.

Jan 1, 1941

By Gabe McClain, Thomas Pallua, Joe Schrank, William C. Gates

Because of restrictions on blasting in urban areas and, more importantly, the proximity of this construction to national historic landmarks, blasting operations were extensively monitored to measure and correlate ground vibrations as peak particle velocity (PPV), frequency, and strain—these being the major factors that would impact the surrounding buildings. As a result, copious amounts of data were gathered and interpreted within a short time to estimate blasting parameters and optimize the subsequent blast rounds

Feb 1, 2020

By Hans Lundberg

IN last year's report on the progress of geophysics, the airborne magnetometer was the featured new development. At that time only a relatively small number of surveys had been made. During 1947, the airborne magnetometer was used in making many surveys and is again one of the high lights of the year in geophysics. This report is mainly concerned with geophysics as applied to the search for minerals exclusive of petroleum. In 194,5 and 1946, the use of the magnetic method reached a peak, partly because of an active period of prospecting brought on by an active mining market, particularly in Canada.

Jan 1, 1948

By Thomas L. Kesler

Essentially all of the barite produced in Georgia has come from the Cartersville district in the northwest part of the state. The earliest recorded shipment of ore, 60 tons, was made in 1894.1 With the exception of the four-year period 1931 to 1934, the separate yearly output has been recorded and published since 1915, whereas the total yearly output of the United States has been published since 1880. The separately recorded production of Georgia (Cartersville) through 1947 is 2,232,544 short tons valued at $14,900,746,2 but unpublished data on the period 1931 to 1934, plus the estimated unrecorded output prior to 1915, make the actual total about 2,400,000 short tons. This is about 21 pct of the total production of the United States, which, through 1947, is 11,328,440 short tons valued at $71,683,386.2

Jan 1, 1949

By Kengo Usui

The energy consumption of Iron-making, especially Blast Furnace (BF), is very large. In order to maximize the utilization of limited resource, it is essential to reduce energy consumption and recovering waste energy in BF. This paper introduces energy saving equipment based on NSENGI’s over 80 BF construction experiences since 1963. The first is the technology for the Top Charging System for low fuel-rate operation. One of the important factors to achieve such operation, the burden should be charged uniformly. Since 1974, NSENGI have developed and delivered over 80 Top Charging equipments for such purpose and nowadays, developed new type Top Charging equipment with improvement of charging precision. The second is the technology for Solely BFG Operation in Hot Stove, which means no use of other fuel gas such as LDG, COG. It is realized by high combustibility of NSENGI’s Top-Combustion Hot Stove with Metallic Burners, and large amount of heat recovery of Waste gas Heat Recovery system with heat medium. The third is the technology for effective energy recovery in TRT. With NSENGI’s latest Gas Cleaning System “Multi-Vessel Electrostatic Precipitator" (MVEP), TRT will be able to generate higher electrical energy by approx. 30% than that of wet-type. In comparison with dry bag-type, MVEP allows temperature fluctuation which lead to generate higher electrical energy by approx. 10% NSENGI therefore, will be able to accept and meet your request widely.

Aug 1, 2018

By D. F. Malan, P. M. Couto

We propose a layout design for the UG2 Reef where weak geological alteration layers are present. The collapse of the Everest platinum mine in South Africa indicated that these layers substantially weaken the pillars. The popular Hedley and Grant pillar strength formula cannot be used where these alteration layers are present. Underground investigations at Everest mine and numerical modelling of the layout were conducted using the TEXAN code and a limit equilibrium model. Simulations of a collapsed area and an intact area allowed for a preliminary calibration of the model. This was subsequently used to explore modified layouts for these ground conditions. An alternative is to compartmentalize the blocks of ore using barrier pillars. The numerical modelling predicted that the barrier pillars appear to remain stable even in the case of large-scale collapses, provided their width exceeds 25 m. Main access routes into the mine can be protected by a double row of pillars at least 15 m wide to provide a safe travelling way. As a cautionary note, these conclusions are based on the model calibration and this needs to be refined in future. Calibration of the limit equilibrium model remains a challenge owing to the large number of parameters involved.

May 3, 2023

By Vinicius Andres Strey

Segurança da informação é um tema crescente dentro do ambiente de Tecnologia de Automação. Da mesma forma que para outras rupturas que ocorreram, as grandes empresas desempenham um papel de vanguarda também quando se fala em segurança da informação. Grandes empresas, no geral, possuem diversas instalações. Neste caso, em se tratando de segurança da informação, é fundamental que os riscos sejam identificados e os controles sejam definidos e implantados de maneira integrada, de modo que vulnerabilidades quando exploradas não afetem o negócio como um todo. Desta forma, recomenda-se fortemente a adoção de um programa de segurança da informação com a participação das diversas instalações em vez de projetos isolados. Este trabalho apresenta a estratégia para o desenvolvimento deste programa através da adaptação de boas práticas e frameworks de referência, como ISA-62443 e NIST SP 800-82. As fases de concepção e desenho do programa estão contempladas, tomando como caso de referência o Programa de Cyber Security para Sistemas de Automação Industrial da Vale. Este programa foi concebido para ser abrangente nos aspectos de segurança da informação, considerando a situação individual de cada mina, usina ou porto envolvido, e estruturado de maneira a ser expandido facilmente para outras instalações.

Jul 30, 2018

By Steven G. Jansto

Carbon content and continuous casting parameters affecting solidification behavior, such as super heat, mold level fluctuation, heat transfer, fine grain chill zone depth and other process solidification parameters directly influence the surface and internal quality of the steel strand. The carbon content, resultant fine grain chill zone depth, the equiaxed-columnar transition zone and the strain energy are the primary drivers that govern hot ductility behavior. These factors influence the propensity for crack formation during the unbending section in the continuous casting process. Elements such as microalloys exhibit secondary or tertiary root causes for crack formation and are not the primary crack formation root cause. This solidification research identifies that the traditional hot ductility as measured via the percent reduction in area (%RA) at elevated temperature grossly overstates the minimum ductility required to assure crack-free casting of microalloyed steels. The strain at the ultimate tensile strength exhibits a very high correlation coefficient with strain energy while an extremely low correlation coefficient is exhibited with %RA.

Oct 30, 2017

By A. Singh, R. D. Govender

The current method employed to quantify the efficiency of separation of ferromagnetic ores by wet low intensity magnetic drum separators (WLIMS) incorporates the use of a conventional benchscale Davis Tube (DT) operating at a magnetic field intensity that is equivalent to that of the drum’s surface. However, empirical research has indicated that the magnetic force, or force index, rather than the magnetic field intensity, is the critical factor in the operation of the magnetic separator (Murariu and Svoboda, 2002). Furthermore, the current aforementioned practice would yield incorrect information as the magnetic field gradients produced by a typical WLIMS unit differs considerably from that of a bench-scale DT. In light of this, research on magnetite focusing primarily on the scale-up of DT results to pilotscale WLIMS were undertaken. The investigation entailed a comparative study between that of a typical WLIMS circuit and a bench-scale DT. The purpose was to practically evaluate the performance of a WLIMS, bench-marked against the traditional laboratory-scale DT unit. Moreover, the secondary objective was to produce a magnetite concentrate graded at 69% Fe, 95% -45μm, as a suitable source of separation media for use in the Dense Medium Separation (DMS) industry. Fundamental findings of previous works provided a framework for the study, however, a realworld approach was explored. Preliminary testwork conducted at Mintek investigated the performance of a DT and a typical multi-stage laboratory-scale WLIMS circuit (operating at 1000 Gauss at the surface). The results attained indicated that a DT operating at high intensities is comparable to a single rougher WLIMS stage. Additionally, it was observed that the three stage laboratory-scale WLIMS circuit performed similarly to the DT operating at 1000 Gauss. Moreover, piloting testwork was undertaken, carried out in larger 380mm drums, and the results attained showed a strong correlation with laboratory-scale findings. Keywords: Davis Tube, wet low intensity magnetic separation, magnetite

Jan 1, 2020

By Q. Cui, B. Z. Zhou, Z. G. Song, Y. G. Zhu, G. B. Zheng

The complex refractory Cu-Pb-Zn polymetallic ore in Xinjiang, China is a massive sulphide ore with complex mineral components. In the past two years, the ore mineralogy has changed, resulting in a decline in metallurgy, with too much zinc reporting to the lead and copper concentrates. A detailed mineralogical study indicating the presence of secondary copper minerals, which could be activating the sphalerite early in the present circuit, was used to develop a novel reagent and flotation flowsheet termed “Pb-Cu co-flotation, Cu intensified flotation, Zn flotation”. It was tested and found to significantly contribute to improving the flotation performance of the ore. In the Pb-Cu co-flotation circuit, successful depression of pyrite and sphalerite was achieved using a BK612- Na2S based depressant system. Most of the galena and some of the Cu bearing minerals with excellent floatability were collected with the use of the selective collector BK906. The rest of Cu bearing minerals were floated in a copper Z200 circuit using a BK537-lime-zinc sulphate based depressant scheme. Zinc flotation from the copper tailing was performed in a SIBX circuit using lime as a pyrite depressant. Using the proposed flowsheet, overall Pb, Cu, and Zn recovery increased significantly to 88%, 87%, and 90% respectively. Keywords: Complex polymetallic ore, Cu-Pb-Zn, Pb-Cu co-flotation, particle size

Jan 1, 2020

By G. Mahieu, L. Perez-Barnuevo, P. Barbeau-Verreault, O. Gravel

Raglan mine is a copper-nickel mining operation, part of Glencore, and located at the northern border of the province of Quebec, in Canada. The concentrator is fed by a mix of four different underground mines, thus it must accommodate periodic variations in run-of-mine mineralisation and composition. In order to concentrate nickel and copper sulphides, the flotation circuit also includes a regrind step at the cleaner stage. This leads to challenges in maintaining optimal recoveries and in diagnosing potential disturbances. This paper advocates for the combination of automated mineralogical analyses, reconciliated mass balances from diagnostic sampling campaigns and innovative multidimensional visualisation to assist in tackling these challenges. Through this approach, it has been possible to quantify the regrind step influence on the liberation of valuable mineral particles in the final flotation concentrate. The methodology also allows for virtual sieving of the products in order to track unit loss in the flotation process. The proposed analysis scheme presents an opportunity to easily diagnose flotation circuit performance based on mineralogical information. Keywords: Flotation diagnostics, multi-dimensional visualisation, mineral liberation analysis

Jan 1, 2020

By J. C. Edwards, C. C. Hwang

A computational fluid dynamics (CFD) program was applied to fire spread along combustibles in a ventilated mine entry. The rate of flame spread was evaluated for the ribs and roof of a coal mine entry; timber sets; and a conveyor belt. The CFD program models char forming materials with temperature dependent thermal properties. The program solves three dimensional time dependent flow equations with a mixture fraction model for the gas phase reactions. Radiant heat exchange is evaluated for non-scattering gas. The CFD program predicted a flame spread rate of 0.0145 m / s for an actual coal mine fire in which the estimated flame spread rate was 0.0086 m / s. This overestimated flame spread rate was a possible consequence of the presence of inert materials in the mine entry’s roof and ribs. CFD fire spread rate predictions of 0.043 m / s and 0.73 m / s bounded the measured value of 0.27 m / s for fire spread along Douglas Fir timber sets in a tunnel.

Jan 1, 2006

By S. N. Dixon

"Maximizing the value of each tonne of processed ore is the goal for all operations. Cyanidation processing of gold-copper ores has been challenging since its first use in 1889. The current practice treats a bleed or the total flow of mill solution to recover copper as copper sulfide (by sulfidization, acidification, recycling, and thickening), or to recover the cyanide (by acidification-volatilization neutralization). The process presented uses the adsorption of copper cyanide by carbon and the selective elution of copper from carbon to concentrate copper into a smaller stream. Copper contained in the smaller stream is precipitated as copper cyanide.RÉSUMÉ Toutes les exploitations ont pour objectif commun d’optimiser la valeur de chaque tonne de minerai traité. Depuis sa première utilisation en 1889, la méthode de traitement par cyanuration des minerais aurifère et cuprifère s’est révélée complexe. La pratique actuelle traite la saignée ou le débit total d’une solution de traitement du concentrateur pour récupérer le cuivre sous la forme de sulfure de cuivre (par sulfuration, acidification, recyclage et épaississement), ou pour récupérer le cyanure (par acidification, volatilisation et neutralisation). Le procédé présenté dans cet article utilise l’adsorption sur charbon actif de la solution de cyanure de cuivre et l’élution sélective du cuivre depuis le charbon pour concentrer le cuivre en un plus petit jet. Le cuivre contenu dans ce plus petit jet est précipité sous forme de cyanure de cuivre.INTRODUCTIONProcessing gold-copper ores by cyanidation has been a cost-control challenge since the cyanidation process was first used in 1889. Copper cyanide is stable only in the cuprous state, not the cupric. This factor results in the oxidation of a mole of cyanide per mole of nonchalcocite copper extracted. Each mole of copper extracted forms a cyanide complex with a minimum of 3 mol of cyanide. This cyanide-to-copper mole ratio is required to dissolve gold. The oxidation of cyanide and copper complexation with cyanide results in high cyanide consumption for copper-gold ores, which is a significant operating cost.One challenge in processing gold-copper ore is the cost of cyanide related to the extraction of copper. Processing 10,000 t/d of ore containing 1,000 mg/kg copper and 10% copper extraction yields 1,000 kg/d of copper. Currently, processes to remove copper from cyanide leach solution treat either the total flow of the barren or a bleed of the barren. The two processes used for copper-gold ores are sulfidization, acidification, recycling, and thickening (SART), which produces a copper sulfide product for sale; and acidification- volatilization-neutralization (AVR), which recovers the cyanide from a gas and produces a low–cyanide content solution. This low–cyanide content solution can be recycled to the process or might require additional treatment before being disposed from the operation."

Jan 1, 2017

By Rhulani F. Maluleke, Francis W. Petersen, John H. Marsh, Johann de T. Steyl, Allan Nesbitt

"Pressure leaching of chalcopyrite and nickeliferrous pyrrotite at temperatures between 105 and 200 ºC has been proposed as a potentially viable route for the extraction of mineral elements from sulphide concentrates. In general, these concentrates contain iron, and the economic success of the processes is partially dependent on the choice of the environmentally acceptable iron-removal technique. One of the most widely used methods for the removal of iron from sulphate liquors is precipitation as hematite, goethite, or jarosite. The nature of the iron precipitate formed dictates downstream dewatering and residue treatment and disposal options. However, a better understanding of iron precipitation under the defined process conditions would consequently be of benefit in process design and optimisation.This study investigated the precipitation of iron in the autoclave at temperatures between 105 and 200 ºC. The effects of temperature, acid concentration, iron concentration, and the presence of other metal cations on the nature and composition of the precipitates were determined."

Jan 1, 2003

By R Varden

This paper summarises the process taken to simplify 35 ground support standards accounting for the multiple development profiles, dynamic geotechnical environment and the practical safety implications of a large-scale change in the ground control standards. This reduction was required after an incident involving incorrect standards being issued. The subsequent investigation identified that: • Selection of ground support standard for a mining instruction (MI) is not straightforward due to multiple standards, standards not reflecting current reinforcement used and complex geotechnical environment being encountered. Instead, site-specific ground control instructions were being issued. • Ground support standards were hard to follow and confusing, errors were present and not all standards to scale. • Ground support standards being used did not reflect what was being installed, ie bolt type incorrect and mesh orientation different. • No process or tier action response plan (TARP) for operators to follow for ground control standard noncompliance. • No justification for ground support standards being used in the current geotechnical environment. • No process for ground support standard selection and thereby no paper trail to document and assess adequacy of performance. A project was undertaken to reduce and simplify the ground support standards, produce a justification document to support ground support design and develop a process for site practitioners to identify the type of ground support standard required for the mining instruction. The exercise of rationalising the ground support was met with some challenges, including: • Technical aspects to determine the level of demand and the capacity for each ground support scheme. • Training the geotechnical engineers how to determine the level of risk for each area. • Winning over other technical services staff and the underground mining contractor of the new approach and then implementation. One of the major successes was the acceptance by the underground operators who found the system simplified their work and gave them increased confidence in management of seismicity. The rationalised ground support standards have now been successfully in place for over two years.

Mar 29, 2023