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By J. -C. Sztuke, M. Cao

ABSTRACT Wash water and polyethylene oxide (PEO) were used in the flotation of quartz and coal. Wash water decreased entrainment of –15 µm quartz. The optimum superficial wash water rate was 0.05 cm/s. PEO also lowered entrainment. The combination of wash water and PEO led to a slight further reduction in entrainment. For 1:1 mixtures of –15 µm quartz and –300 µm oxidized coal, the combined use of wash water (0.05 cm/s) and PEO increased the separation efficiency from approximately 30% to > 70%, whereas wash water alone at 0.05 cm/s did not lead to a discernible increase.

Jan 1, 2014

By A. O. Dady

PRODUCERS of both bituminous and anthracite coal have for many years been worrying about the gradually decreasing consumption of their product in the United States. Twenty years ago production had climbed to a peak of 569,000,000 tons of bituminous and around 90,000,000 tons of anthracite. In 1939 it was about 393,000,000 tons of bituminous and 51,000,000 tons of anthracite. This does not mean that the country is using less polver than it did twenty years ago, or that we are living in colder buildings. As a matter of fact, about three times as much electric power is now being consumed as in 1920. In general two factors are responsible for the drop in coal consumption: (1) greater efficiency in the use of coal, and (2) increased competition from hydro power, internal-combustion engines, and substitution of oil and gas for coal in conventional furnaces. As to the first factor, it took 3 Ib. of coal to generate a kilowatt-hour of electricity in central stations in 1920 and it takes 1.4 Ib. now; it took about 175 Ib. of coal in railroad locomotives to haul 1000 long tons a mile in 1920 where it talces about 120 lb. now: and marked economies have also been made in the use of coal in steel plants: in by-product coke ovens, and in other large uses. As to the second factor, three times as much electricity is produced from water power now as was produced in 1920; three times as much oil is being consumed in various ways; and likewise, the consumption of natural gas has tripled- whereas coal consumption in the same period has dropped by 40 per cent

Jan 1, 1941

By L. V. Bell

THE object in prospecting is to find ore. With the exception of certain discoveries of more or less accidental nature, intelligent prospecting as conducted today is, whether consciously or not, based upon a process of elimination. In the following discuss on it is proposed to evaluate those factors that enter into the eliminating of certain tracts of ground and, conyersely, the concentrating of attention upon others. The danger of generalizations as to the barrenness of cer.ain areas, without having due regard for all such factors, is emphasized. The fact that our conception as to what areas or rock formations are to be regarded as favourable or unfavourable is, in some measure at least, changing with new discoveries under diverse and unexpected circumstances, adds more point to the discussion. The criticism might be raised that the subject is treated largely from the standpoint of geology, but that may be met by stating that it is, and must continue to remain, precisely from this standpoint that the prospecror directs his activities. Briefly, the geologist may render the greatest service to the prospector in the early steps of selecting (a) the general territory in which to prospect; (b) the area to be intensively prospected; and, finally, (c) those parts of the claim or claims to be prospected in detail. Although certain phases of the discussion will be, in some measure, of general application, we shall here concern ourselves essentially with prospecting in the pre-Cambrian shield. Furthermore, the subject is so large that it has been decided to limit it to a consideration of that portion of the pre-Cambrian rocks in which is situated the mining district of western Quebec, of which the writer can speak with more personal knowledge. This limitation need not, however, seriously detract from whatever merit the discussion may possess, since the deposits concerned cover a fairly wide range of metallic ores, including gold, copper with associated zinc, and, lastly, molybdenum.

Jan 1, 1936

By Walter Camahuali A

A partir de la década del 50, el ANFO como elemento de voladura seco y producto de mezcla de nitrato de amonio en prills y petróleo diesel, fue utilizado en el campo de los explosivos. Posteriormente, su uso se mantiene en países occidentales, Europa y Perú, dado que para obtener un ANFO es necesario el nitrato de amonio como agente antioxidante. En este sentido, el presente trabajo describe la técnica denominado ANFO aplicado en diferentes minas de tajo abierto subterráneo, así como refiere la norma técnica que fue aprobada para el ámbito nacional y sus requisitos.

Nov 8, 1984

By Michael J. Magyar

The Federal Bureau of Mines has developed a hydrametallurgical method to recover aluminum, aluminum oxide, and fluxing salts from aluminum salt slags. The slag is leached with water at room temperature to produce a saturated brine slurry. Screening of the slurry yields an aluminum-rich fraction that can be returned to the dross furnace. The remaining slurry is vacuum filtered, yielding a clear brine solution and an aluminum oxide filter cake. Evaporation of the clear filtrate produces a high-purity fluxing salt for reuse in the dross furnace. Over 80 pct of the metallic aluminum is recovered in the aluminum-rich oversize fraction, while essentially all the fluxing salts are recovered by evaporation. This report contains the final results of an investigation on a process research unit scale, an economic evaluation of the method, and recommendations to further improve the process.

Jan 1, 1979

By L. G. Huntley

Points out differences between the new, more liberal, law passed by the Colombian Congress and the law passed in 1919, gives a few facts about the pipe-line concession granted to a Canadian company, and tells of new drilling developments. PROBABLY the most important development in the Colombian oil situation during the past year was the passage by Congress of a new petroleum law, which went into effect Jan. 31, 1923. The principal points of interest in which this new law changes or improves the previous one are as follows: Law 120 of 1919 provided that one person or corporation could not acquire more than three exploitation zones. of 5000 ha. each, and royalties were based on a sliding scale, to wit: 6 per cent. royalty on lands 400 km., or more, from the ocean; 8 per cent. on lands 200 but not over 400 km. from the ocean, and 10 per cent. royalty on lands located less than 200 km. from the ocean. Rentals were fixed at 10 centavos per hectare for the first year; 20 centavos for the second year; 50 centavos, third year, and $1 (one peso) yearly thereafter. Under this law the term of the lease was fixed at 20 years and, at the discretion of the government, could be extended for 10 years additional. After the expiration of the lease and its corresponding extension, the machinery and other material placed upon the property would vest in the government. A bond of 20,000 pesos was also required of the lessee to guarantee faithful performance of his contract.

Jan 3, 1924

By J. F. Smith

ELASTIC constants of yttrium and eleven of the rare earth elements have been measured. This has been accomplished by measuring the propagation velocities of ultrasonic pulses. The velocity measurements were made by noting the elapsed time between an applied pulse and the appearance of successive echoes. The pulse-echo technique has become relatively common, and the basis of the measurement is outlined in several standard tests, e.g., Heuter and Bolt.1 Two important assumptions are made when using this method for the determination of elastic moduli. First, the pulse is assumed to propagate as a plane wave. To justify this assumption, the cross section of the test specimen should be large compared to the wave length of the transmitted pulse. For these measurements on the rare earth elements the minimum cross section wave length ratio was about 20. A second assumption which must be made when using polycrystalline specimens is that the grains are sufficiently numerous and randomly oriented so that the specimen may be approximated as elasti-cally isotopic. The grain size in the as-cast specimens which were used is believed to be sufficiently fine for this approximation, and the degree of preferred orientation is believed to be small. Supporting this viewpoint is the fact that elasticity measurements by the pulse-echo technique on as-cast specimens of other metals give results which are in satisfactory agreement with values obtained by other techniques. Hence, it is believed that the measured elasticity values for the rare earth elements are not apt to be seriously in error due to the assumption of elastic isotopy. The apparatus used in this determination was a modified Sperry Reflectoscope with a precisely calibrated time base circuit. Piezoelectric transducers were used both to generate the pulse and to detect the echoes. X-cut quartz crystals were used for the longitudinal modes, and Y-cut quartz crystals were used for the shear modes. Frequencies of 2.25 and 5 megacycles per sec were employed. Most of the specimens were 2.5 to 5.0 cm in length. Results Table I is a tabulation of the measured propagation velocities of longitudinal waves and of shear waves, together with densities obtained by Sped- ding, Daane, and Herrmann2 from lattice parameter measurements. The shear modulus, Poisson's ratio, and Young's modulus were calculated from the data in Table I through use of the following relationships: µ = pv32 [1] s=2-(vb/vs)2/2[1-(vb/vs)2] [2] and Y= 2µ(l+s) [3] where s is the shear modulus, Y is the Young's modulus, s is Poisson's ratio, p is the density, V0 is the longitudinal wave velocity, and v, is the shear wave velocity. The calculated quantities are shown in Table 11. Compressibility values can be computed from the relationship and the computed values may be compared with measured values obtained by Bridgman.8 Table III lists the data for such a comparison. The agreement is satisfactory, being particularly good for neodymi- um and gadolinium, poor for samarium, and intermediate for the other elements. Some variation is expected since Bridgman's measurements are isothermal, whereas the present measurements are adiabatic. In addition there may be some effect due to small variations in purity. Though most of the rare earth metals measured by Bridgman and all of the metals used in the present measurements were prepared at this laboratory, minor purity variations might exist since the samples came from different lots. Also, any imperfections such as dislocations, vacancies, voids, grain boundaries, microcracks, etc., should contribute to the volume change of a com-

Jan 1, 1958

By J. D. Miller

Air-sparged hydrocyclone (ASH) flotation is a high-capacity flotation technology originally developed in the Department of Metallurgical Engineering at the University of Utah for processing mineral resources. However, the technology has been found to be useful in industrial waste processing, in the recycle of secondary resources, and in remediation of environmental problems. For example, areas in which the ASH technology is expected to have potential application include cleaning of waste coal fines, air stripping to remove volatile organics from drinking and process water, water disinfection by ozone or chlorine sparging, dispersed oil removal from water, and contaminated soil remediation. Recently, the ASH has been studied extensively for deinking flotation in the wastepaper recycling industry and has been shown to have excellent efficiency/capacity. In fact, a 20-million-dollar plant has been in operation since June 1992. The ASH technology can provide a specific capacity hundreds of times more than that which can be achieved with conventional flotation equipment and in certain instances is expected to provide superior separation efficiencies when compared to other technologies. The design and principles of ASH flotation are described. Experimental data for fine coal flotation, volatile organics stripping, and deinking flotation for paper recycle are presented and discussed. Finally, other potential areas of application for environmental technology are considered.

Jan 1, 1993

[HORACE MOSES President Gamerco, New Mexico BENEDICT SHUBART Secretary-Treasurer 521 Boston Bldg., Denver, Colorado ROBT. L. HAIR Vice-President for Colorado VIRGIL R. McKNIGHT Vice-President for New Mexico A. E. GIBSON Vice-President for Utah THOS. FOSTER Vice-President for Wyoming EXECUTIVE BOARD COLORADO: J. B. DICK Walsenburg C. M: BILLINGTON Lafayette NEW MEXICO: W. C. HOLMAN Dawson ROBT. WYPER Gallup UTAH: R. R. KIRKPATRICK Sunnyside GEO. A. SCHULTZ Latuda WYOMING EDWARD BOTTOMLEY Kleenburn QUINCE RICE Superior]

Jan 1, 1926

By Boyd Guthtrie

[Methods of distilling topped crude oils and distillates under vacuum, accompanied by good fractionation, have taken a place of major importance in the refining industry. In the refining of petroleum products it is generally desirable to produce a distillate of good quality, and this objective is attained by fractionation of a high degree. The laboratory and commercial practice have proved chat by varying the amount of fractionation the quality of the distillate car be changed, and refiners are cognizant of the advantages of good fractionation. Distillation-under high vacuum, however, is a relatively new practice in petroleum refining, and only during the last few years has there boon an indication that that this method ray become a general practice in the industry. Vacuum distillation offers many advantages over older methods of distilling petroleum products. Vacuum combined with steam distillation, for example, is replacing straight-stream distillation because the quality of the products of vacuum and, steam distillation surpasses that of those produced by straight-steam distillation. Although the injection of varying amounts of steam in a vacuum unit is common practice, the amount of steam used is becoming less as the vacuum within the unit is increased. This report describes tie construction of a visible-action laboratory batch still and fractioning; column and. gives curtain data pertaining to the operation of the apparatus under vacuum for the production. of lubricating distillates. The apparatus was designed and built to produce lubricating distillates under as nearly ideal conditions as possible, in order that a subsequent study of the characteristics of the distillates could be made.]

Jan 1, 1932

By Stanislas Mauuary

Price pressure is a real challenge on the stainless steel market. With market globalization, increase production capacity and exorbitant raw material, the margins are squeezing for stainless strip producers. Primetals Technologies offers a wide range of advanced technological solutions to secure the margins of our customers. Our solutions, implemented with professional project management, allow an optimum coil to market time, securing then the return on investment for the investor. Among the possible lever used to optimize the production route, one drastic step can be made to cut rolling time and cost by replacing the common 20-Hi mill stand reversing process by state of art high capacity X-HI® stands in continuous rolling line. Other source of savings can be implemented by integrated several process steps together (rolling, annealing, pickling, skin passing), achieving then savings on stocks and logistics while coil processing is reduced to fraction of hour. Additional solutions can also be implemented on the new, as well as existing line, like maintenance free solid state laser welder, skin-pass and tension levelers, in-line inspection system coupled with process and quality management system.

Aug 17, 2017

By Oliver Bowles

"Introduction.During recent months the Bureau of Mines has conducted a detailed study of the slate industry with special reference to increased efficiency in its production, preparation and utilization. The results of these investigations will be incorporated in a forthcoming bulletin. The purpose of this preliminary paper is three-fold. One object is to bring to the attention of slate producers certain modifications in manufacture and classification which would encourage a wider use of slate. A second purpose is to direct the thought of roofers toward the importance of proper laying of slate, and the third object is to acquaint the general public with its enduring qualities.Origin and character.Without entering into any detailed discussion of the origin and history of slate, a subject to be covered in the bulletin mentioned, it may be of interest to the general reader to know that slate is originally formed from mud or soft clay, carried down by streams and laid down in successive layers in deep water. The pressure of superimposed materials gradually compresses the clay into a firm rock known as shale. In many places this shale was, during the succeeding ages, subjected to intense pressure and folding due to mountain-building forces within the earth. This intense pressure, together with high temperature, changed the clay into other minerals such as mica, chlorite, and silica, which are very resistant to weathering, and also developed a very definite cleavage or splitting direction which characterizes the rock as slate. It is this property which renders slate of value for roofing, for, by using a broad chisel and a wooden mallet, a slate worker can readily split it into thin sheets which are later trimmed into rectangles of various sizes."

Jul 1, 1921

By G. P. Gu, B. Fang, R. W. Revie, M. Elboujdaini

Stress-corrosion cracking (SCC) tests were conducted in the near-neutral pH standard solution, NS4, and in an actual soil solution, using four-point bending at high a stress ratio and low frequency conditions very similar to those of operational pipelines. Pitting incubation appeared first and then pitting initiated and grew in both solutions although there were many more pits on the specimen tested in soil purged with 5% CO2 + 95% N2 than in the specimen tested in NS4 solution purged with the same gas. These observations show that samples in soil solution are more susceptible to pitting than those in NS4 solution. When the pit reached a critical size, the increased stress concentration around the pits, resulted in the transition to a crack.

Jan 1, 2005

By Kai Wang, Chao Xu, Qiang Fu, Tong Yang, Chunyu Zhao, Wei Zhao

The stress of a coal seam is an important factor that affects the permeability of the coal seam and then affects the coalbed methane (CBM) drainage. In China, adjacent coal seam mining is an important method to reduce stress, which increases the permeability of the coal seam. However, in the process of mining adjacent coal seams, many coal pillars remain, which causes stress concentrations and results in a decrease in permeability. Therefore, it is important to study the influence of coal pillars on the stress of adjacent layers and its distribution and evolution in the floor rock. This paper took the Shendong Baode Coal Mine as a case study and investigated the influence of the coal pillar on the stress and permeability of coal seam #11. The results show that under a coal pillar, the relationship between the vertical stress of different floor depths and the width of the coal pillar can be divided into a negative correlation zone, transition zone, and positive correlation zone. The change in the coal pillar width does not affect the pressure relief range or the degree of pressure relief in the adjacent coal seams below the goaf. The field measurements show that after the mining of panel #81,505, the permeability coefficient of coal seam #11 under the goaf increased from 0.1434 to 26.3545 m2/( MPa2*d), increasing 182.7 times, and the drainage mixing volume of boreholes #1 and #2 increased from 1.24 to 1.52 m3/ min. While the permeability coefficient of coal seam #11 from 12.5 m in the coal pillar has only increased by 2.6 times, the drainage volume of boreholes #3 and #4 did not change significantly.

Nov 19, 2022

By R. L. Bruening, L. Navarro, Izatt. S. R., R. Adiga, R. M. Izatt, N. E. Izatt, A. Sharma, N. R. Patel, B. V. Rao

Bismuth is a notorious contaminant in the electrolytic refining of Cu that can cause cathodes to fail to meet ASTM International standards and not be suitable for use in Cu rod and other downstream products. Bismuth can significantly decrease electrical conductivity, decrease the mechanical strength of the annealed wire, retard recrystallization, and sometimes induce hot shortness during the hot rolling process in the production of rod. As a result, the control of Bi in the refinery tankhouse must be carefully managed. This paper describes how SuperLig® Molecular Recognition Technology (MRT) is being used for Bi removal at the Birla Copper Dahej Copper refinery. The operation of the SuperLig® MRT Bi removal plant is described and data on Bi removal efficiency are presented. INTRODUCTION Hindalco’s Cu division, Birla Copper, operates one of the largest Cu refineries in the world at Dahej, Gujarat; India. The main feed for this refinery is produced at the company’s smelter. Due to its massive production capacity, this operation mainly relies on imported Cu concentrates resulting in a variety of metals being carried out as impurities in the Cu anodes because pyrometallurgical technologies alone are not enough to remove them to the extent required. Metal impurities found in Cu ores include Fe, Zn, As, Pb, Bi, and Sb. During electrorefining, less noble metals dissolve in the electrolyte gradually increasing their concentrations creating the need for electrolyte control mechanisms that remove these impurities with varying degrees of success (Wang, 2004; Navarro et al., 2013.) Bismuth is one of the most significant impurities in a Cu refinery because it has the lowest ASTM product specification. This situation is critical because the Bi potential is very close to that of Cu making it possible to plate in the Cu cathode directly. Also, Bi can precipitate at high concentrations causing floating slimes and reduction of current efficiency (Ballinas, San Miguel, Munoz, & Gyves, 2003). Production of high purity cathodes from feed stock containing a diverse range of metal impurities becomes a major challenge in the refining of Cu (Izatt et al., 2015). In this work, the purification strategy followed by Birla Copper for the removal of Bi using a separation process based on MRT is presented, outlining the loading and stripping performance of SuperLig®83 and the benefits of using MRT over other lower selectivity methods where hazardous materials are produced instead of high purity products.

Jan 1, 2019

By P. Roman, L. Daneshmend

"During the last decade, mining companies have been overwhelmed by technological solutions to perceived problems. This is particularly true with information technology where rapid advances have resulted in a professional climate characterized by technomania — the perception that failure to adopt emerging technologies will result in a loss of competitive advantage. This paper describes the applicability of structured analysis and design techniques as an appropriate methodology for integrating emerging technologies in the mining industry. The potential of this approach to improve overall mine effectiveness through improved communication and co-ordination between operations and maintenance is discussed. IntroductionA strong working relationship between the operations and maintenance departments in both open pit and underground mines is fundamental to the overall success of the mining endeavour. Unfortunately, for many mines, this characterization is far from accurate. Short-range production targets dominate the day-to-day management of the mines. This can be seen in Bostwick and Buchanan’s (1993) report on American Barrick Resources efforts to achieve an aggressive 415 000 tpd mining program at their Goldstrike operation in Nevada. When production managers do not meet their quotas, the finger is often pointed at maintenance. As a result, a confrontational culture can develop between the two organizations, resulting in a lack of cooperation that exacerbates the problem. Historically, production planning has taken priority over maintenance planning. This is reasonable since production is the primary purpose of the mine with maintenance serving in a support role. This basic relationship remains intact today. However, the trends toward mechanization, increasing levels of automation, and larger equipment, have resulted in increased reliance on the equipment used in the mine. As a result, downtime costs now go well beyond the direct labour associated with the repair of the machine. Lost production costs due to downtime resulting from failed equipment are becoming an increasingly important factor in determining a mine’s overall economic performance."

Jan 1, 2001

Jan 1, 1902

By Yuanbo Zhang, Yongbin Yang, Guanghui Li, Zhengwei Yu, Yufeng Guo, Tao Jiang, Xiaohui Fan, Youming Hu

"Composite agglomeration process (CAP), as an innovative method for preparing blast furnace burden, was developed and has been put into operation in China. CAP is different from traditional agglomeration processes of iron-bearing materials involving sintering and pelletizing. Compared to the traditional agglomeration processes, CAP is characterized by several strengths such as permission of diverse iron-bearing materials in production, obvious improvement of permeability in the feed bed, decreasing the fuel consumption and remarkably increasing the productivity of sintering machine. Furthermore, the use of the composite agglomerates prepared with CAP is capable of obviating the negative effects caused by the differences in quality of sinter and pellets on the operation of blast furnaces. This paper mainly presents an overview of the principle and applications of CAP.Development Background and Principle of CAPhe traditional agglomeration processes including sintering and pelletizing have been the two predominant methods for preparing ironmaking burden from iron-bearing materials. Sintering is a way for agglomeration by heating the coarser fine ores (general granularity 0~10mm). The mechanical strength of irregular porous sinter is obtained by the solidification of molten phase at high temperature process. It has been shown that the production of high basicity sinter (R=1.8~2.2) is characterized by low energy consumption and high efficiency compared to low basicity sintering. Meantime, the finished high basicity sinter is characterized by good mechanical strength and metallurgical performance. Pelletizing is another way for agglomeration by firing wet green pellets, which are balled from the fine grained iron ores or concentrates. Based on the differences of chemical compositions, the finished pellets can be divided into acidic oxidized pellets, fluxed pellets, magnesium-bearing pellets, and so on. The acidic oxidized pellets are the dominant products of modern pelletizing."

Jan 1, 2012

By Jaime Herrero, Santiago Gómez, Pablo Segarra, José Ángel Sanchidrián

This paper presents a mathematical model for the study of the 2D movement of blast bench faces based on the high-speed video analysis of three blasts at El Aljibe quarry (Spain) recorded at 2,000 frames per second. In these blasts, a set of bags of 0.75 × 0.75 m were placed in front of a selected blasthole defining a reference plane in which to study the kinematics of the movement. The burdens range from 3.86 m to 5.54 m, with a bench height of 12–13 m. An affine transformation system was calculated to convert coordinates from the video images into actual spatial coordinates. The problem is established from a multi-objective minimization approach in order to simultaneously optimize two defined objectives: trajectory fitting using Total Least Squares regression, and time–displacement regression using Ordinary Least Squares. Muti-objective minimization formulation produces Pareto plots of non-dominated solutions, i.e., optimal combinations of initial velocities and response times, (i.e. time between detonation and the onset of bench face motion). From the Pareto frontier, the most balanced solution is selected. Blast response time lasts only a few milliseconds and appears so brief at the frame rate used that it is difficult to detect visually. In this context, the bi-objective optimization-based approach proves to be a more robust tool than frame-by frame survey for quantifying such a rapid event while also maintaining a strong performance in the trajectory fitting task. Root Mean Square Error (RMSE) for the two minimizations average 0.22 m and 0.13 m, respectively. The initial velocities obtained range from 4 to 17 m/s, and the response times 0.7 ms to 21.7 ms. An analytical model is also presented for predicting fragments initial velocity and response time as functions of blast geometry and rock mass properties, explaining approximately 87% of the total variability.

Jan 26, 2026

By Christopher B. Vierrether

Reflected light microscopy, scanning electron microscopy, and electron microprobe analysis have been used to determine the mineralogy, phase percentages, grain sizes, textures, and partitioning of cobalt and nickel in two cobalt-nickel rich mattes. These mattes were prepared by submerged bath smelting from a flotation cobalt-nickel concentrate containing 4.8% cobalt and 5.1% nickel. The concentrate was derived from lead-zinc-copper ores of the Viburnum Trend, southeast Missouri. Eleven discrete phases have been distinguished in the matte samples, three of which contain significant cobalt and nickel. The phases are cobaltpentlandite ((Co,Ni,Fe)9S8), cobalt-bearing marmatite ((Co,Fe,Zn)S), shandite (Ni3Pb2S2), bornite (Cu5FeS4), galena (PbS), magnetite (Fe3O4), pyrrhotite ((Co,Ni,Cu,Fe)1_xS), chalcocite (Cu2S), CuPbS phase, metallic copper, and metallic silver. Cobaltpentlandite and cobalt-bearing marmatite- occur in coarse grains (50 µm) that would separate readily during grinding, but shandite contains small (5 - 10um), abundant inclusions of pyrrhotite and bornite.. Some mineralogical variations between the two matte samples were due to differing degrees of oxidation during smelting,

Jan 1, 1988