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By A. Pirson, J. Souza, A. Araujo, M. Barbosa, F. Guimarães, J. Lima

"Although a large number of processes have been developed and applied to the separation of barite from other minerals, there is a lack of information in the literature about the separation of barite from iron ores. Nowadays, there are millions of tonnes of iron ore disposed as a waste or tailings given its high content of sulphur in the form of barite. In order to effectively separate barite from iron ore and ensure that mining business is truly creating economic and sustainable values, this paper provides a greater understanding of barite properties, the origin and occurrence of this barium-bearing mineral, and the employed beneficiation processes. A test work is conducted in a barite bearing iron ore from a deposit located in the Republika Srpska (Bosnia and Herzegovina) in order to separate the barite and check if a marketable by-product can be produced by drawing upon rich barite tailings. INTRODUCTION The exploration of iron ore containing barite results in a large amount of unrecovered material. The main difficulty in processing and using barite bearing iron ores is given by their high content of sulphur, silica and barium, which are unwanted chemical compounds in the subsequent processes in iron industry. As a result, millions of tonnes of iron ore are discarded every year into tailings or as a waste, which results in production losses, higher operation costs and environmental impacts (Praes et al. 2013). Therefore, the separation of barite from iron ores not only means reducing the environmental impact, but also an opportunity to generate income and beneficiate society. The beneficiation of barite bearing iron ores is a subject which requires a deeper investigation to solve the challenges faced by the iron industry. There are only a few studies that describe flowsheets proposed for the production of barite concentrate of iron ores. The most likely reason for this gap is that barite is frequently exploited commercially as a primary product rather than a by-product. In order to effectively separate barite from iron ore and ensure that mining business is truly creating economic and sustainable values, this paper provides a greater understanding of barite properties, the origin and occurrence of this barium-bearing mineral, and the employed beneficiation processes. A test work is conducted in a barite bearing iron ore from a deposit located in the Republika Srpska (Bosnia and Herzegovina) in order to separate the barite and verify if a marketable by-product can be produced by drawing upon rich barite tailings."

Jan 1, 2018

By E. C. Bain

THE more familiar compositions of iron-carbon-chromium1 and the iron-carbon-tungsten2 systems have been investigated with a degree of thoroughness which has permitted the construction of their three-dimensional equilibrium diagrams; and it is probable that these equilibrium diagrams are sufficiently accurate for the present metallographic needs. Strangely enough, in spite of their importance, the alloys of iron, carbon and manganese apparently have not been investigated in the same systematic manner, and so far as is known, no three-component equilibrium diagram for this system is available. Even iron-carbon-nickel alloys3 have been studied rather more thoroughly; for these the solidus and liquidus surfaces have already been determined, but the solid transformations in this, as in the manganese system, have not been reported systematically. The present paper deals with the constitution at equilibrium of a series of 36 iron-carbon-manganese alloys of commercial purity limited by 1.5 per cent carbon and 15 per cent manganese, a range of compositions including most of the manganese steels. The temperature range of melting has not been determined, nor has the high-temperature (delta iron) ferrite equilibrium been included in the study, it being considered that the more important characteristics of the manganese steels are their ordinary transformations in the solid state. The delta iron region is almost certain to be a small tetrahedron not very different in magnitude or contour from that in the iron-carbon-nickel diagram. It is probably true

Jan 1, 1932

By Arthur C. Spencer

ThRee great deposits of iron-ore, in Camaguey and Oriente Provinces, Cuba, are well known to me through careful field-examinations executed in the years 1901 and 1907. In 1901 I visited the Cubitas iron-ore district, which lies about 12 miles distant from the city of Camaguey in a northerly direction, and the Mayari district, which includes the Sierra Nipe, lying opposite Nipe bay on the north side of Oriente Province. In 1907 I again visited the Cubitas district, and also made a sojourn of several days in the Moa district, where the extensive deposits of iron-ore were observed and studied. The observations of 1901 were made under the auspices of the then Military Governor of Cuba, Gen. Leonard Wood, and my conclusions concerning the value of these deposits were incorporated in a report.' The examination of certain denouncements of iron-ore in the Moa district in 1907 was made in behalf of iron-masters operating in the United States, to whom I reported the existence of large amounts of easily-workable limonitic iron-ore, properly designated " brown iron-ore " in the terminology now current among iron-ore producers in the United States. In 1908 I published a paper entitled, Three Deposits of Iron Ore in Cuba, outlining the occurrence and origin of the surfi-cia1 ores existing in the Cubitas, Mayari, and Moa districts.2

Jan 1, 1912

By Oliver W. Keener

This paper describing the methods and costs of mining at the Hartley-Grantham mine of the Century Zinc Co. in the Tri-State Lead and Zinc district is one of a series being prepared by the United States Bureau of Mines can mining practices, methods, and costs in the various mining districts of the United States. LOCATION, HISTORY, AND GEOLOGY The Hartley-Grantham Mine is located just outside the city limits of Baxter Springs, Kans., as shown in Figure 1. A plan of the mine is given in Figure 2, and Figure is a cross section through A - A of Figure 2.

Jan 1, 1930

By Yuanbo Zhang, Bingbing Liu, Zhuyin Chen, Xiao Kang, Chen Liu

Composite agglomeration process (CAP) is an effective method to utilize the iron-bearing dusts generated in the ironmaking plants, by which the dust percentage in the sinter feed can be increased up to 20 wt %. In the current study, a comparison on behavior of iron-bearing dust in the conventional sintering process (CSP) and CAP was characterized. The results showed, in the CSP products, the scattered iron-bearing dust in the mixture was disadvantageous for the sintering indexes and consolidation of the finished sinters. In the CAP products, the main phase in the iron-bearing dust pellets was well-crystallized Fe2O3 grain particles. In the matrix parts, there were more Fe3O4 particles generated, which caused to high RDI+3.15 and low RI of the finished products. The pellets and the matrix parts were bonded by iron oxides and acicular calcium ferrite.

Jan 1, 2016

By Wagner Viana Bielefeldt, Felipe Buboltz Ferreira, Antônio Cezar Faria Vilela

The continuous casting machine is one of the most important steel production steps in a melt shop. The tundish, a reservoir between the steelmaking ladle and the mold, has great influence over the steel cleanliness, along with the productivity bid. It must takes into account the quality of the metal and operational safety. Several different variables are related to the tundish process, of inclusionary cleanliness. Some of them are discussed in this paper: the free opening of ladle, tundish inertization, steel temperature in the reservoir and clogging formation, besides a brief topic about castability. Therefore, a critical analysis, with a review from some papers available in literature, is proposed in this study, with its focus on tundish.

Oct 1, 2019

By D. E. Wolfson

As a part of its overall program of coal carbonization, the Bureau of Mines is studying the coking properties of coals that may be used for metallurgical purposes. The objectives of this study were given in detail in a previous report.2/ The inherent suitability of coal for metallurgical use depends primarily on (1) chemical composition, (2) preparation characteristics, and (3) carbonization behavior. The first two factors, as well as the available reserves, are considered in selecting coals for carbonization tests.

Jan 1, 1957

By O. C. Blade

This report on the properties of aviation gasolines and aviation jet fuels produced in the United States during 1954 was made under a co-operative agreement between the American Petroleum Institute and the Bureau of Mines of the United States Department of the Interior. Analytical data are presented for 101 samples of aviation gasoline. Data also are given for 30 samples of aviation jet fuel. The analyses were made on samples typical of the manufacturers I 1954 production in their laboratories and the results submitted to the Bureau of Mines for compilation. The products of 19 manufacturers of aviation gasolines and of 15 producers of aviation jet fuels are represented.

Jan 1, 1955

By S Maritsa, E K. Chiw, S M. Masuka, ika, T Chisahwira

The challenges facing the iron and steel industry on a global scale include depletion of resources, excessive energy consumption and CO2 emissions. The demand for iron products in Zimbabwe is increasing due to massive infrastructural development like the expansion and improvement of mines, transportation systems and water reticulation systems. In Zimbabwe, cast iron is mainly produced from recycling scrap metals. However, there is currently a shortage of scrap, which has resulted in the vandalism of state-owned properties such as bus terminals and railway wagons and lines. Nevertheless, Zimbabwe is rich in limonite ores, which are idle, and it is the aim of this research that this ore be effectively used to produce feed for the blast furnace. The Blast furnace is still the dominant route for producing cast iron where sintering and coking processes are the main routes for preparing the Blast furnace feed. Sintering limonite ore fines produce a product of poor grade because of the high value of loss on ignition that has a negative impact on Blast furnace efficiency. Furthermore, the sinter plant and the coke making plant are a source of huge environmental pollutants. Since low-grade Zimbabwean coal fines are also available in abundance, they were used in the preparation of the composite materials ensuring maximum utilisation of this resource. Results showed that the limonite ore-carbon composite pellets sample with the binary basicity ratio (CaO/SiO2) of about 0.27 and coal addition of 2.5 wt per cent achieved above the minimum physical quality requirements for pellet of drop number of at least 4, a dry compression strength greater than 2.2 kg/pellet and an indurated compression strength greater than 250 kg/pellet. Limestone was used as the binder avoiding the addition of more impurities from bentonite since the limonite ore has a high SiO2 content of about 8.78 wt per cent.

Sep 18, 2023

It is now widely accepted that horizontal stress is present nearly everywhere underground. Often it is more severe than the vertical stress. It is a major cause of roof control problems in underground mines. The AHSEM computer program contains two modules to improve mine layouts for control of horizontal stress. For development, the user specifies the orientations of the maximum horizontal stress, the entries, and the crosscuts. Angled crosscuts may be used, and the angles may be different for the right- and left-hand crosscuts. AHSEM then shows the user how the stress condition would vary as the entry and crosscut orientations are changed. The second module is for longwall mining. Severe stress concentrations can make headgate conditions hazardous when the entries are improperly oriented. AHSEM shows whether a particular longwall orientation and extraction sequence places the headgate corner in a stress concentration or in stress relief. It also estimates the magnitude of the stress concentration.

Apr 1, 2003

By Jose Ruiz Huidobro

El presente texto señala los aspectos propios de la demasía como concesión minera, prescindiendo de aquellos otros que son comunes a toda clase de concesiones mineras. La demasía se entiende como una concesión que ocupa el área libre existente entre los linderos de dos o más concesiones cuando esta área no permite la conformación de una hectárea. La determinación de su extensión relaciona la colindancia con las concesiones que forman la demasía. Los desplazamientos de las concesiones limítrofes después de delimitada la demasía benefician a ésta siempre que no resulte limite con una concesión que originalmente no era colindante.

May 1, 1958

By P. Kostuik

"Recent interest in the pipeline transport of solid mate-als has been sparked by the idea that, in an inflationary onomy, pipeline costs are more stable than the costs of any other transport systems. Pipelines have proved over 1e years to be dependable, records indicate that main-•nance and operating costs are comparatively low, and 1eir amenability to automation is of considerable im->rtance.The concept of hydraulic hoisting of solids from under-round, or cross-country hydraulic transportation of con-~ntrates and ores, is currently of prime interest to the ining industry. In general, this paper deals with a preliminary investi-ation of energy losses incurred while transporting a rela-vely heavy, crushed mine product, namely magnetite, oth vertically and horizontally. The basis and validity of everal equations derived by other experimenters to com-ute these losses is discussed. A theoretical analysis of ydraulic hoi:,,ting is made, and, based upon test results, calculation of horsepower requirements for hoisting an re under a given set of conditions is presented. Results indicate that:n vertical transport, the friction head losses are identical to those of clear water, and the total energy requirement for hydraulic hoisting then becomes a function of height of lift, concentration and specific gravity of the solids being hoisted. .-In horizontal transport, friction head losses can be calculated with reasonable accuracy using Bonning-ton's correlation curve. Losses computed utilizing Durand's correlation (K = 85) result in estimates which are too low by 10 to 30 per cent, an<l those calculated using Newitt's correlation (K = 1,100, K = 66) give friction loss values which are too high by 10 to 30 per cent . . -The theoretical horsepower (RMS-hp.) required for hoisting hydraulically is approximately half of that required for conventional double-drum skip hoisting."

Jan 1, 1966

By Wright R. J

The Commission called tenders for a four boom hydraulic jumbo, plus basket, on an art- iculated carrier in Sept. 1977. Atlas Copco submitted the successful tender in Jan. 1978 for the supply of a three boom jumbo, plus basket. The Promec TH470 jumbo was commiss- ioned in the 2000 m long Sophia tunnel in Nov. 1978. Adequate spare parts were not available during the first three months of operation and the hammers could not be overhauled at the recommended interval. One hammer was removed after drilling 13 600 m due to a crack in the intermediate housing. Tests were conducted with different types of drilling consumables. Both rope and Hi-teed threads were tested and found compar- able. The average penetration rate in the granite was 1.1 m/min. Initially the drillers were not experienced enough to operate the BUT 15ERH booms without causing damage to the booms and hoses. Drilling deviation espec- ially of the perimeter holes was greater than expected. It is now obvious that greater attention must be given to attracting, train- ing and retaining the right type of operator and maintenance fitter.

Jan 1, 1981

By F. Garacia, J. Cervik

Gob holes are routinely used by the mining industry to vent methane from gobs and to prevent it from entering the mine ventilation system. In some cases, flows from gob holes are measured by centering an anemometer on the end of a discharge pipe. These measurements are erroneous and tend to be high by as much as 30 pct. The Bureau of Mines deter- mined method factors (correction factors) for anemometer measurements taken in this manner. Method factors for 4-, 6-, and 8-in (10.2-, 15.2-, and 20.3-cm) ID pipe are 0.68, 0.71, and 0.78, respectively. Comparisons between horizontal and vertical flows indicated no significant change in method factors. Consequently, the method factors for horizontal pipe flows can be applied to vertical upward flows.

Jan 1, 1987

By William H. Lehr

In recent years, we have witnessed many innovations in the equipment used in handling bulk materials. Not too long ago, any sizeable stockpile of coal or iron ore was attended by one or more material handling bridges. More recently, large stockpiles have been built with mobile equipment of&apos; the earth moving type with bulldozers and front end Loaders being utilized in reclaiming operations. The most recent stocking and reclaiming device is the rotary bucket wheel machine. The early bucket wheel machines built in the United States were developed for the strip mining of coal. We understand that the first American machine was built in the Midwest in 1944. This type of unit was developed in an effort to reduce the cost of removing overburden and to provide satisfactory spoil disposal. As the available coal reserves under shallow cover were exhausted, the cost of removing the deeper overburden with conventional equipment became too great for these operations to continue profitably. The first machine has now been followed by six or seven additional units, the largest of which can handle material at a rate of more than 7000 cubic yards per hour.

Jan 1, 1965

By Muller GP, van Deventer JSJ

A mineralogical analysis has shown that in the Hartebeesfontein ore studied, uranium is associated mainly with uraninite, sulphides such as pyrite and to a lesser degree carbonaceous material such as thucolite. Little could be learned from the literature regarding the mechanism of flotation of these uranium-bearing minerals. A wide variety of reagents were used so that conditions enhancing the flotation of either the sulphides, carbonaceous material, oxides like uraninite, or combinations thereof, were created. As could be expected, the xanthate based floats gave-better selective recovery of sulphides than oleic acid. A substantial fraction of the uranium is associated with pyrite, so that addition of oleic acid to a xanthate float did not enhance the recovery or grade of uranium. After a pre-leach with sulphuric acid in which the pH and Eh were controlled so as to destroy the uraninite, higher uranium recoveries were obtained for the combined float (xanthate, DTP and oleic) and the DTP float. This was most evident when iron was added before flotation. Roasting, which destroyed the sulphides and thucolite, caused a significant decrease in uranium recoveries. The uranium liberated in this way was obviously not flotable in the same way as the uranium liberated from uraninite. A small amount of iron (2 kg/t) added before milling resulted in slightly higher grades and recoveries of sulphur for xanthate based floats. Higher iron additions had a detrimental effect on sulphur recoveries. Even in the case of oleic acid the addition of small amounts of iron had a positive effect on the recovery of sulphur and uranium.

Jan 1, 1993

By T. T. Read

"Employee representation in the management of large mining enterprises was first introduced in organized form, by the Colorado Fuel and Iron Co. in 1915. Within the past few years a number of the larger mining enterprises have introduced similar systems and there is growing interest in the subject. This will be stimulated by the final report of the President's Second Industrial Conference, in which the following statement occurs:""The conference finds that joint organization of management and employees where undertaken with sincerity and good will has a record of success. The general principles governing such organizations are stated at length under the title 'Employee Representation. It is not a field for legislation, because the form which employee representation should take may vary in every plant. The conference, therefore, does not direct this recommendation to legislators but to managers and employees.""If the joint organization of management and employees in the plant or industry fails to reach a collective agreement, or if without such joint organization, disputes arise which are not settled by existing agencies, then the conference proposes a system of settlement close at hand and under Government encouragement, and a minimum of regulation. The entrance of the Government into these problems should be to stimulate further cooperation."""

Mar 1, 1920

By Zhucheng Huang, Lingyun Yi, Bin Chai, Tao Jiang

"A high iron content manganese ore was reduced at 900~1200°C and followed by a magnetic separation process. SEM and EDS analyzes were employed to examine the transformation of microstructure and phase in reduced sample and the mechanism was revealed. Results showed that elements enriched during reduction. Iron existed in the metal iron phase and most of oxygen formed compound with manganese. Consequently a clear distinguish between iron phase and manganese minerals formed, which was beneficial to the separation of iron and manganese. But the iron phase can not be monomer dissociation in grinding process and manganese compounds turned into magnetic product as package and mechanic inclusion due to the isomorphism of iron and manganese and the small particle size. And MnO could be found partially in iron phase, which hindered the further separation of manganese and iron.IntroductionManganese is widely used in industry. The amount of manganese used in steel industry is very huge and 90% manganese is used in steel industry. Manganese ore resources are rich in China, yet with fewer rich ore but more low-grade ore which accounts for 93.6% and fine refractory ore. The constitution of the ore is very complex and more than 73% of all the manganese ore contains iron[l,2]. With the increasing of consumption of steel, the demand for manganese is becoming larger and larger and the imported ore accounts for more than 50%. Therefore, how to use the manganese ore efficiently has very significant meaning. The main method is manganese residual, which is simple and stable. However, the development of the method is limited by the quality of manganese ore, the huge amount of manganese residual, the technology of blast furnace process and economics[3,4]. Chemical benefication which may pollute environment and is difficult to recover iron is still being researched[5,6]. The paper investigated the process in which anthracite coal was the reducing agent for coal-based direct reduction and magnetic separation of the ore, and SEM with EDS measurements were employed to examine the transformation of phase in reduced sample and the mechanism was revealed[7,8]."

Jan 1, 2013

Minutes of meeting held at the Moth Hall, Witbank on 13th November, 1969. There were present eleven members: Mr J. Meintjes (in the chair); Messrs I. E. van Aswegen, O. T. Wright, A. W. L. Brereton, A. Bain, J. Brook, P. J. Beukes, C. H. Coxon, B. F. v.d. Merwe, A. C. Hofmeyer, G. E. Carlyon. Six Associate Members: Messrs E. J. Jackson, J. N. H. Pritchard, R. E. Powell, W. Weber, R. Smith, B. T. Hosking. One Student Member Mr M. J. de Beer. Seven visitors. The Chairman reminded members of the intended visit to Barberton. Dr Stander, Director of the National Institute for Water Research, gave an interesting talk, illustrated with slides and a short film, on the conservation and reclamation of water in South Africa. After question time, Mr Hector, Witbank Town Engineer (visitor) thanked Dr Stander. The meeting closed at 7.10 p.m.

By C. M. Smith

PILOTED by Cadwallader, Evans, Jr., as chairman, the Coal Division got under way Monday morning for the first of three consecutive sessions. N. F. Patton started the ball rolling with a paper on the economics of anthracite distribution, which was ably discussed by H. J. Rose, W. S. Blauvelt, and others. Mr. Patton pointed out many incongruities in freight rates, dealers&apos; margins, and other factors which are disturbing the distribution of anthracite, one result being that trucks are hauling at least six million tons of anthracite annually, half of which is stolen. In the discussion of the papers the desirability of greater uniformity in the production and shipment of coal from month to month was urged; with larger summer price concessions as a means toward this end. "Performance Expectancy of Domestic Underfeed Stokers for Anthracite," by Allen J. Johnson, brought this important platter down to date by showing the range in capacities and efficiencies to be expected from well-made stokers, and by detailing other of their operating characteristics. One of his most interesting points is that the efficiency of domestic stokers is practically equal to that of handfiring for good installations and operations of both

Jan 1, 1935