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By Jorge Morales

El presente trabajo señala las definiciones sobre la gestión de activos, requerimientos básicos, aplicación práctica y un modelo mediante un mapa de ruta para una industria minera de gran escala. En ese sentido, el reto de este mapa estriba en ser un modelo organizacional donde uno identifique lo que hace bien y las brechas de oportunidad, defina los procesos para lograr los objetivos y así ensamblar esos procesos comprobando la coherencia y el alineamiento con la estructura, estrategia y cultura organizacional. Finalmente busca desarrollar las soluciones, el plan y la toma de acciones y así aprender de las consecuencias.

Jun 1, 2015

By K. S. TWITCHEEL

THE different lines leading out from the vocation of a mining engineer are,' perhaps, the most' varied of all the professions. The expedition sent by Charles R. Crane of New York 'as a gift to the Imam Yahia, king of the Yemen, Arabia, was probably unique. Mr. Crane made a visit, in January,1927, to the Imam Yahia at Sanaa, capital of the Yemen. He was received with the utmost cordiality and respect, as his friend- . ship for the ,Arab world is famous; He was 'greatly impressed by the desire of the Imam to develop his country. The Imam stated that he had heard that there were minerals in his country and that he would like to secure engineers to advise him about them and other natural resources.. This seemed such a practical idea, and so greatly appealed to Mr. crane, that he offered to furnish an engineering 'expedition. Naturally the Imam gratefully accepted. This expedition was to study (as far as possible in 'the limited time) the natural resources of the ,Yemen, advise the Imam of what these consisted, and make suggestions regarding the most practical methods for their development. As agriculture is always such a fundamental part of a country's wealth, I first went to Indio, California, to study water-well drilling and the date industry, and eventually arrived at Hodeidah, the principal Yemen seaport, on Oct. 21, 1927.

Jan 1, 1929

By A. T. Tye

This paper describing the concentrator practice of the Cananea Consolidated Copper Co. at Cananea, Sonora, Mexico, is one of a series of articles on milling methods and costs being prepared by the U. S. Bureau of Mines. The Cananea concentrator treats 2,400 tons of copper ore per day by preferential flotation, whereby the copper sulphides are floated and the iron pyrite depressed. During the first half of the year 1929 the heads to the concentrator averaged 3.29 per cent of copper, the recovery was 95.74 per cent of the total copper, and the concentrates produced contained 21.44 per cent of copper.

Jan 1, 1930

By John Dilworth

IN considering the valuation of industrial properties in general, and of developed coal properties in par-ticular, it is assumed as fundamental that they have but one true value regardless of the object for which they are appraised. As regards developed coal lands, this value is only very approximately indicated by the recent sale price of neighboring lands, for the reason that it is rarely possible to find a sale of a coal property sufficiently similar in essential mining conditions to the one under consideration to serve as a measure of its value; and if such a one is found there are frequently incidental conditions peculiar to this particular transaction which invalidate the use of the sale price as a measure of general values. The true measure of the value of a coal mining opera-tion is the amount and rate of earnings it will afford with intelligent and experienced management. Prac-tically all of the features of a property which are gen-erally recognized as affecting its value relate either to the cost of producing the coal, or to the price it will bring, and so are intimately associated with earnings. In practice it is customary to appraise those portions of a developed coal property which are produced -by the industry of man-mine plant, equipment, development, town, etc.-at their cost of replacement at prevailing prices of materials, machinery, and labor, with such deductions for age, condition, obsolescence, and lack of usefulness as conditions warrant. Surface is appraised at the estimated cost of similar land in the district. Coal value is the difference between the worth of the entire property; considered as an industrial unit and

Jan 9, 1927

To enable ammonium nitrate-fuel oil (AN-FO) to be used on an equal weight basis with nitroglycerine explosives, smaller diameter bore holes became necessary with consequent modifications to drill steel and burden on holes. Detonation of AN-FO in small diameter holes proved successful both with and without primer charges but some alterations were required to adapt anoloders to the smaller holes.Important factors in training all operators in the new charging method were the retention of improved fragmentation, avoidance of excessive overbreak and keeping wall rock dilution to an absolute minimum. The successful storage of ammonium nitrate in climatic conditions with daily temperature fluctuations above and below the critical 90°F has been achieved.INTRODUCTIONTechnical aspects of ammonium nitrate-fuel oil (AN-Fa) blasting agent are well covered in recent literature. This paper deals primarily with the manner of its introduction as the principal explosive underground at Great Boulder Gold Mines Ltd. and with the many problems encountered in the process. Following reasonably successful experimental firings in June 1962', using granular ammonium nitrate and an anoloder, permission was granted by theWestern Australian Mines Department to carry out test work in selected areas of the mine. The permit allowed for fuse firing only, and for a mixture of AN-Fa containing between 5t and 6 per cent fuel oil, with an adequate primer.The use of AN-Fa on an equal weight basis with nitroglycerine explosives, involved smaller diameter holes with alteration to ground burden and modification to drill steel.Initial tests indicated that it was apparent that AN-Fa could not replace gelignite on an equal weight basis if the...

Jan 1, 1965

By Shakuntala Tudu, Indrajit Paul, Surajit Sinha, Pulibandla Basaveswara Rao, Shaik Mahaboob Basha, Srinivas Dwarapudi

The iron and steel manufacturing sector directly accounts for 7–9% of global CO2 emissions. Raw material preparation, such as iron ore sintering, pelletizing, and cock making, is the major CO2 emitter. As climate change becomes a bigger concern, steel manufacturers need to lower CO2 emissions without hindering efficiency or increasing costs. In recent years, the percentage of iron ore pellets in blast furnaces has increased due to its uniform size, good reducibility, and high tumbler index. Pelletizing is energy-intensive and emits considerable CO2. Around 20% of CO2 emissions during pellet making come from fluxes. In the present work, the authors established a novel CO2- free flux called wollastonite (CaO.SiO2) for sustainable palletization. Pellets with varying percentages of wollastonite (0–6%) are prepared and tested for chemical, physical, and metallurgical properties. Image analysis through an optical microscope is carried out to quantify the phases of fired pellets. SEM–EDS is performed to evaluate the chemical composition of the melt and slag phases. The results showed that the reducibility index (RI) and swelling index (SI) of pellets decreased with an increase in wollastonite dosage. Pellet strength increases with an increase in wollastonite addition up to 1.2% CaO (2.27% wollastonite), and a decrease in strength is observed thereafter. The increase in strength is attributed to the increase in slag bonds. The decrease in strength beyond 1.2% CaO is mainly because of an increase in low melting eutectics and more magnetite content. Pellets with 2.27% wollastonite to get 1.2% CaO showed good physical and metallurgical properties.

Mar 4, 2024

By L Soebari, W Sunyoto

The Wabu Ridge Gold Skarn deposit is located at elevations of up to 3100 metres above sea level, in the Central Highlands of Irian Jaya, Indonesia, 35 km NNW of the Grasberg porphyry deposit. Wabu is a grass-roots discovery in an area with no previous gold mining history or record of gold mineralisation. A geological resource of 117.26 million tonnes at an average grade of 2.16 g/t Au (1.0 g/t Au cut-off) has been defined to-date. Mineralisation is hosted within a skarn occurring along the southern boundaries of the Late-Miocene age monzonite-diorite Pagane intrusive complex. The intrusive complex occurs in the footwall of a major EW structure, the Derewo fault, which displays sinistral strike-slip and reverse fault movement. The Derewo fault separates Derewo metamorphic units to the north from platform sediments of the Australian craton to the south. The skarn has a strike length of 6 km and is up to 1.5 km wide. It is developed within calcareous shelf sediments of the Tertiary New Guinea limestone group and is dominated by prograde garnet development. Gold mineralisation was deposited during retrograde alteration and is directly associated with arsenophyrite and bismuth minerals. Retrograde alteration is distinguished by a sequence of clinopyroxene , magnetite, epidote and hornblende, biotite and chlorite and lastly carbonate. Gold is associated with the biotite/ chlorite phase together with sulphides and precipitated as the result of fluid mixing. The Wabu Ridge Gold Skarn deposit was identified in April 1990 during a regional program of helicopter assisted stream sediment sampling of -80 mesh (180 microns) fraction and panned concentrate sampling. The initial discovery sample site was situated 15 km down stream from the deposit and returned 1.49 ppm Au for the stream sediment sample and 138 ppm Au for the panned concentrate sample. A regional airborne helicopter magnetics survey, conducted in early-1992, helped defined the main magnetite associated skarn zone and the extent of associated igneous rocks. Detailed follow-up commenced in May 1992 and consisted of detailed mapping, soil sampling and ground magnetics prior to drilling the first hole in October 1992. Drilling to-date has delineated a contained geologic resource of 8.1 million ounces of gold and potential exists for a larger resource.

Jan 1, 1999

7133. Clewell, D. H. The Gravimeter. Prec. and Trans. Texas Acad. Science 1941, Austin, Tex., vol. 25, 1942, pp. 86-88. Static gravimeters, unastatized and. astatized, are considered to be the most practical for oil exploration. One gravimeter is described using a beam whose moment about a pivotal axis is elastically balanced. Magnetic or electric fields are deemed unsatisfactory for balancing gravitational force because they cannot easily be kept constant. The gravimeter described is capable of detecting a change in altitude of 3 inches and a change in latitude of about 150 feet. V. S.

Jan 1, 1944

By Robert F. Conley

Attrition milling, once employed exclusively for the dispersion of pigments, has in recent years found a host of new applications in the area of mineral processing and mineral-pigment production. Broadly categorized, attrition milling is divided into two classes, as defined by the machinery's function, vibratory milling and rotational milling. Each mill type has been defined as a variation on ball milling and the terms, "vibratory ball mill" and stirred ball mill" appear in the literature. The primary design differences between attrition and ball mills are: (1) a stationary canister (or shell) (2) smaller grinding media (3) grinder energy is motor limited rather than gravity limited (4) strong media/feed size dependance.

Jan 1, 1983

By E. N. Harshman

Uranium mining and milling are rather new industries in Wyoming and South Dakota, but, in the past 15 years, ore valued at more than $400,000,000 has been mined and milled in the region. The major uranium deposits are in structural and/ or erosional basins or on the flanks of uplifts. The principal host rocks are medium- to coarse-grained sandstones that were deposited in continental or brackish-water environments and were derived in large part from the granitic cores of the uplifts and the sedimentary rocks that flank the cores. The ages of the host rocks range from Cretaceous to Miocene, but more than 95 per cent of the known reserves in the region are in rocks of early Eocene age. The bulk of the ore in the region is unoxidized and lies below the water table; some oxidized ore has been mined in the Powder River Basin and Black Hills districts. The unoxidized ore comprises pyrite, uraninite and/ or coffinite, marcasite, hematite, jordisite(?), and selenium. Minerals in the oxidized ore include hydrous uranium carbonates, phosphates, and sulfates and hydrous uranium and/ or vanadium silicates. The deposits are in the form of ore rolls that contain from a few hundred to a few hundred thousand tons of ore, ranging in grade from 0.1 per cent to 1.0 per cent U3O8. The rolls are at the margins of large tabular bodies of sandstone that has been altered by the orebearing solutions. The deposits are believed to have resulted from the interaction of an alkaline; oxidizing, ore-bearing ground water and a reducing environment. Exploration guides include the spatial relations of ore to altered sandstone, favorable lithology in the host rock, the content of certain elements and/ or compounds in ground water, and the relation of deposits to major paleodrainages.

Jan 1, 1968

By F. E. Lathe

INTRODUCTION THE present study, based largely upon phase equilibrium diagrams and other theoretical considerations but nevertheless addressed primarily to the practical metallurgist, has been undertaken with a view to discovering what light can be thrown upon the role of alumina in slags. According to Liddell (23), "alumina apparently acts as .a base if much silica is present, as an acid if the silica is low, always as a nuisance." Newton and Wilson (26) state that .alumina "is never added intentionally, as it makes the slag viscous, and is generally an undesirable constituent of slags". Camp and Francis (3) sum up their views by saying, "alumina is seldom used intentionally as a flux, but it is present in nearly all raw material, hence unavoidable". One has only to read The Function of Alumina in Slags, by Henrich (I3), and the very extensive discussion that followed the presentation of his paper, to realize that, before the days of phase equilibrium diagrams, it was a very serious question indeed as to whether alumina should be calculated as a basic, acid, or neutral constituent. Opinions then differed widely, as well they might; today, even though no categorical answer can be given to the question raised, the function of alumina can be at least partly clarified by a study of the fundamental work done by the Geophysical Laboratory in Washington and by certain universities in both America and Europe. It will be a source of gratification to Canadian metallurgists and ceramists to know that work of this type is now under way in the recently organized Physical and Crystal Chemistry Section of the Mines Branch, Ottawa, and that results of practical value have in fact already been obtained.

Jan 1, 1951

By M. Nusheh, C. Bumby, A-H. Puichaud

"Vanadium-bearing titanomagnetite ironsand deposits occur along a 480 km stretch of the west coast of New Zealand. In the present study, the leaching behaviour of NZ ironsand was investigated in hydrochloric acid (2–10 M) solution at 50–80°C for 2 h. The resulting leaching liquors exhibited Fe/V ratios in the range 150–180. The distribution of trace element contaminants between solution and solid residue was investigated, and processing conditions have been determined for rapid and efficient dissolution of Fe, Ti and V into the leaching solution. In addition, mineralogical analysis of raw ironsand and leached residues was performed in order to study the leaching mechanism. Samples were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy (EDX), X-ray fluorescence spectroscopy, qualitative and quantitative X-ray diffraction and inductively coupled plasma mass spectrometry (ICP). Results indicate that the dominant dissolution process follows shrinking particle mechanism. However, ironsand particles containing ex-solution lamellae exhibited a different leaching behaviour compared to homogenous titanomagnetite particles.INTRODUCTION Titanomagnetite ironsand (blacksand) forms Quaternary onshore beach and dune deposits and offshore marine deposits (Figure 1) along 480 km of coastline from Kaipara Harbour south to Wanganui on the west coast of the North Island (Christie, 2016). It attracted the attention of scientists from the earliest times (Galbreath, 1998). The principal minerals in ironsand are titanomagnetite (TTM), ilmenite, quartz and ferromagnesian minerals such as augite, hornblende, diopside, and olivine with smaller amounts of rutile and apatite (Mauk, 2016).Several large ironsand deposits have been discovered and exploited since the late 1960’s. The Waikato North Head and Taharoa mines are currently operating and they have a 2015 measured resource of 400 million tonnes in total and provide over 2 million tonnes of concentrate per year by simple cost effective magnetic separation process (Christie, 2016; Christie & Brathwaite, 1997). The concentrate contains not only 7–8% TiO2 and 56–60% SFe, but also 0.3–0.6% V2O5, is both a valuable titanium mineral and a source of vanadium. All the production is used for steelmaking industries. The other potential for utilizing more of this resource without requirement of integration into an iron and steel producing plant is to develop a hydrometallurgical route with advantages of higher efficiency along with lower emissions. Currently, there is no existing commercial process capable of extracting all three of these elements as industrial-grade commodity products. Acid leaching of TTM concentrate with higher degrees of recovery and selectivity is a key step in any possible hydrometallurgical route."

Jan 1, 2017

The General Purpose Simulation System (GPSS) is a computer simulation language that has been used for simulations of open pit haulage operations since the 60's. It is easy to learn, simple to use, and has a block-diagram structure that is amenable to load-haul systems. However, due to its lack of flexibility, there are situations where another language should be chosen. This paper reviews the characteristics and capabilities of both GPSS and FORTFAN with regard to open pit shovel and truck simulation. The relative advantages and disadvantages are highlighted and a case study presented along with comparative results from two computer models (one written in GPSS and the other written in FORTRAN).

Jan 1, 1986

By James C. Barker

The Bureau of Mines evaluated the tin development potential of the uplands between the Kanuti and Hodzana Rivers from 1978 through 1980. Chemical and petrologic data indicate that local granitic intrusions are generally similar to "tin granites" that contain tin deposits elsewhere. The tin mineral cassiterite (SnO2) was identified in chlorite-rich greisen from the Sithyiemenkat pluton. Greisen zones are located near the intersections of high-angle, linear structural features, and samples contain up to 0.23 pct Sn. One bedrock exposure of greisen is 10 to 15 ft wide. Although some lode mineralization is present, the deeply eroded nature of the region suggests larger tin-bearing cupolas may have existed prior to erosion. Extensive stream gravel deposits have not been affected by glaciation, and potential exists for placer tin deposits. Especially favorable is a large semiclosed basin drained by the Kanuti Kilolitna River. Heavy mineral concentrates collected from surface alluvium in the Kanuti Kilolitna River valley contained up to 51.2 pet Sn (0.02 to 0.4 lb/yd3 Sn), up to 5 pct W, up to 0.4 pct Cb(Nb), and up to 0.1 pct Ta. The concentration of heavy minerals is expected to in- crease with depth. Detailed mapping and extensive surface and subsurface sampling will be needed to quantify the mineral development potential of the lode and placer tin deposits in the uplands.

Jan 1, 1986

By Arthur Forsyth

A SEARCH through the available literature shows that the cobalt-nickel-silicon system has not been systematically studied. This seems rather odd because all three elements are fairly abundant and have better than average corrosion resistance; however, they have high melting points, which makes experimental work difficult. Cobalt and nickel form a continuous series of solid solutions and each metal dissolves about 7.5 per cent silicon. Many ternary alloys have been studied and the results have been published in a great many different ways, but to present such data in a short but clear and understandable manner is still a problem. The following pages describe the results of the study of 76 alloys from which the partial ternary diagram (Fig. 1) of the cobalt-nickel-silicon system has been drawn. The alloys were chosen according to the plan in Fig. la by taking definite ratios of cobalt and nickel, such as 70 Ni, 30 Co or 40 Ni, 60 Co, and adding silicon in various percentages. Each section was studied in detail by means of thermal analysis and microscopic examination, but only two of these detailed sections were thought necessary in the point perspective drawing to give a comprehensive picture of the liquidus, solidus and solid transformations that take place over the temperature ranges studied. Complete thermal analyses and microscopic data are given in Table 1.

Jan 1, 1940

John Duer Irving, who left his post as Professor of Economic Geology at the Sheffield Scientific School, New Haven, Conn., to join the Eleventh Regiment of Engineers shortly after the declaration of war, died in France, July 26, 1918, from an attack of pneumonia. Through the initiative of Mr. Benjamin B. Lawrence, a memorial service to Captain Irving was held at St. Paul's Chapel, Columbia University, on Sunday afternoon, August 4, which was' attended by members of Captain Irving's family, and about four hundred of his friends from Columbia, Yale, the American Institute of Mining Engineers and the Association of the 11th Regiment of Engineers. Professor James F. Kemp delivered the memorial address, and has prepared for the Institute the following account of Captain Irving's life, Professor Kemp and Captain Irving having been associated on the most intimate terms for a number of years. , The war has brought home to friends and kin in the western shores of thc Atlantic many losses whose suddenness has the shock of a blow. Many more will follow, but none can leave a sharper sense of regret than the news that the keen and productive mind; the inspiring teacher; the successful and considerate editor, the fine, true man and friend had all passed away when John Duer Irving made the final great gift to the service of his country, in the cause of decency and right. In the closing days of July, the cable brought the tidings that toward midnight on the twentieth of the month pneumonia had proved too great a tax upon one already worn by excessive labors. John Duer Irving was born in Madison, Wis., August 18, 1874. His father, Roland Duer Irving, was at the time professor of geology, mineralogy and metallurgy in the State University of Wisconsin.' Roland . Irving, the father, had entered Columbia College in 1863, but trouble with his eyes compelled him to suspend his studies in the classical course in his sophomore year, and to replace study with some months of life and travel in England. Ultimately his eyes became stronger, and he entered the School of Mincs, completing the course for the degree of Engineer of Mines in 1869, with the third class graduated. The class of eleven contained other future geologists. It numbered on its roll Henry Newton and Walter P. Jenney of the early survey of the Black Hills, where John, future son of Roland, was in the course of years to make his doctor's dissertation, and with its publication his really serious entrance into the profession. Roland Irving was a favorite student of Professor J. S. Newberry, affectionately known to all of his students as "Uncle John," and after some experience in mining and smelting in Pennsylvania and New Jersey, joined the Ohio Survey under Dr. Newberry. The work in Ohio was largely performed during the vacations of the University of Wisconsin, to whose chair Roland Irving was called in 1870. Later, his residence in Wisconsin led to two events of prime importance in the history of American geology. He began the study of the Gogebic iron range and caught the clue to the origin and stratigraphy of the iron ores of all the Lake Superior ranges; and he later undertook the mapping and description of the copper-bearing rocks of the Lake Superior basin. The formative years of the son, John, were passed in a home where the father.

Jan 1, 1920

By W. H. McAllister

The paper considers the geology and the coalfields that comprise the Scottish south area. It traces the history of known sources of spontaneous combustion and indicates the collieries concerned, with the position of the seams in the geological series where heatings have occurred. The methods of work over the years are described. It relates in detail the circumstances surrounding a fire at Bilston Glen Colliery in the Lothian Coalfield, and the heating at Killoch Colliery in the Ayrshire Coalfield, and the steps taken to deal with them. It also describes some of the difficulties in steep seam working. Methods adopted to prevent spontaneous combustion throughout the area are discussed, and some detail of the UNOR gas analyser is given. Finally, it comments on the present techniques in use in the area, particularly at Bilston Glen Colliery, to prevent spontaneous combustion.

May 23, 1905

By LEE H. CORNELL

Drilling activity in Kansas during 1945 continued at an accelerated pace to meet the demands of war; 1810 tests were drilled as compared with 1856 tests the previous year, 1771 tests in 1943, and 1516 tests in 1942. During the year 31 new oil pools and 10 new gas pools were discovered. Of a total of 364 wildcats drilled, 323 were dry; and of 1446 tests drilled in pools, 825 were oil wells, 197 gas wells, and 425 dry holes.

Jan 1, 1946

By P. A. Hendricks

This U.S. Bureau of Mines (USBM) report identifies and evaluates factors responsible for metal/nonmetal (M/NM) underground mining accidents involving mobile equipment. Information regarding the occurrence and severity of the accidents, the type of equipment involved, the primary and contributing causes, and preventive measures is included. The goal of this report is to provide information that will aid mine operators and safety managers in the recognition of hazards associated with operating mobile mining equipment in an underground mining environment.

Jan 1, 1994

By C. L. Elmore

This paper describes a new development in the cyanidation of gold ores, which we expect will result in a major improvement in the way many gold ores are treated. The process has evolved through work at Hazen Research, Inc. for Kamyr, Inc. and in brief, the consists of utilizing oxygen rather than air in the carbon-in-1 each (CIL) process. We refer to this improved process for all ores amenable to cyanide leaching as carbon-in-1each with oxygen or CILO.

Jan 1, 1988