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By J. E. Murphy, R. Y. Wan, K. R. Sandgren, M. C. Fuerstenau

As part of a U.S. Bureau of Mines program to evaluate alternatives to sodium cyanide in gold leaching, three organic nitrile compounds were tested for their effectiveness as gold lixiviante. The organic compounds examined were malononitrile, acetonitrile, and cyanoacetamide. The reagents were tested on an oxide ore, two carbonaceous ores, and a eulfidic ore. Acetonitrile and cyanoacetamide were shown to be ineffective gold leachante. Malononitrile was the most successful of the organic lixiviants. On an oxide ore, malononitrile performed shilarlyto sodium cyanide with extractions of around 80 pct. For carbonaceous "preg-robbing" oree, sodium cyanide was completely ineffective while malononitrile extracted 24 pct of the gold. When using a resin-in-leach technique, extraction with sodium cyanide increased to 60 pct and the extraction with malononitrile increased to 80 pct. On the sulfide ore, sodium cyanide and malononitrile performed similarly with 80+ pct extraction as long as the pH of the malononitrile solution wae maintained above 10.5. Malononitrile is six times less toxic than sodium cyanide as measured by LD, levels. Therefore, malononitrile has a significant advantage over eodium cyanide, but its high cost and undemonstrated usefulnees make it unlikely to gain acceptance.

Jan 1, 1993

By F. Daviess

A requirement for geological controls during orebody modeling results from the recognition of heterogeneous geological characteristics and/or abrupt variations in orebody geometries. While purely statistical methods are often sufficient for modeling uniform homogeneous deposits, and the only recourse for many that are extremely complex, geological interpretations can be extremely valuable as controls during the modeling process. The advent of relatively inexpensive, sophisticated graphical computer hardware and software has focused considerable attention on the three dimensional visualization capabilities now available to the mining industry. Orebody geometries can be easily imported into many systems as wireframe or solid models, rendered with shading and color, rotated in space, exploded into composite parts, zoomed into and otherwise displayed to awe any audience. The requirements for an initially meaningful, accurate, geological interpretation are sometimes lost when the focus is on an apparently complex, highly resolved end product. Details of the initial data and sensitivities of modeling assumptions are not always sufficiently scrutinized. Software capabilities have extended the geopoetic license into three dimensions. The new tools, while greatly facilitating model construction and rendering, have done little to expedite basic data preparation and analysis. This paper attempts to briefly summarize the purpose and method of the construction of geological controls. The examples selected are from wire­framing and block modeling; application software processes commonly used in the mining industry today.

Jan 1, 1992

Joseph Esrey Johnson, Jr., had already achieved rare distinction as an able metallurgist, clear thinker, brilliant author, and wise consulting engineer to bankers and operators; he had achieved the essentials of a great career when death cut short his activities on Apr. 4, 1919, in the forty-ninth year of his age. He belonged to a family of iron blast-furnace men and mine managers. His father, Major J. E. Johnson, after serving with distinction in the Army of the North, identified himself with the iron mines and blast furnace at Longdale, Va., with which he was connected during almost his entire business life. It is significant that, during those troublous times of reconstruction in the South, he enjoyed always the affection and respect of his neighbors and associates alike. From him his son obtained not only a thorough training in blast-furnace practice and iron mining, but great personal courage and force of character. His mother, who survives both her husband and sons, possesses rare intellectuality, humor and a tenderness and human sympathy which those who were privileged to know well J. E. Johnson, Jr., recognized beneath his exterior of aggressiveness and will power. In a recently published analysis of the qualities which characterize the world's great men, three traits stand out preeminently; viz., independence, courage, and intellectuality. Each of these characteristics J. E. Johnson, Jr., possessed in extraordinary degree. His early education was obtained under a private tutor at Longdale, and this circumstance probably enhanced , a natural tendency to independence of character and individuality which, however, under the control of his

Jan 5, 1919

Dr. Arthur H. Elliott has been connected with the gas industry for upward of thirty-eight years and was a chemist to whom the industry is deeply indebted for the application of the science of chemistry to its problems and processes. He was born in London, England, in 1851, and was the son-of a physician. While a child he was taken to France, where he received his early education, learning to speak the French language before his native English. His father having destined him for the medical profession, he commenced his studies on his return to England, but his attention being attracted to chemistry, he gave up the study of medicine to pursue that of chemistry. While still a student, he obtained a reputation as an iron and steel analyst, publishing two methods of analysis, one for the determination of sulphur .and the other for the determination of carbon in cast iron. On his graduation from the School of Mines at South Kensington, he left England intending to go to Australia, where an uncle resided, having in mind also the possibility of a trip to China. On his arrival in New York, he met Professor Charles F. Chandler, to whom he had a letter of introduction, and who induced young Elliott to remain. He graduated from Columbia College with the degree of Doctor of Philosophy in 1883. He became demonstrator in chemistry at the College of Pharmacy and afterward professor of chemistry and physics at the same college. He became connected with the Municipal Gas Lighting Co. in May, 1880. In. November, 1.884, when consolidation took place, he became engineer-chemist of the Consolidated Gas Co., which position he held until May, 1910, when he resigned, but was retained as consulting chemist until his death. Recently Columbia University conferred on him the honorary degree of Master of Science.

Jan 7, 1918

By Rossiter W. Raymond

The formal outline of Mr. Hague's life and work is embraced in the following statement, chiefly based upon data furnished by him, at my request, shortly before his death. At that time the probability that I would survive to record his death was apparently small; but I urged upon him the duty of providing, whether for me or for my successor as Secretary of the Institute, trustworthy material for the notice which somebody would some day have to write—and which might otherwise be incomplete or incorrect. Mr. Hague, with characteristic promptness and freedom from affectation, did what I asked of him; and I am therefore able to present an authoritative sketch—concerning the details of which I shall add my own comments, and some particulars obtained from friends. James Duncan Hague was born Feb. 24, 1836, at Boston, Maes., where his father, Rev. William Hague, D.D.,an eminent clergyman, then resided. After a preliminary education in private schools, he studied in 1854 at the Lawrence Scientific School of Harvard University; in 1855 and 1856 at the University of Göttingen, Hanover; and from 1856 to 1858 at the Royal Mining Academy of Freiberg, Saxony. In 1859-1861 he was attached as chemist to a South Sea exploring expedition, sent by W. H. Webb, of New York, to examine Jarvis, Baker, and other islands for phosphate-deposits. After the outbreak of the Civil War, he entered the U. 5. Navy, serving for a year as Judge Advocate to the fleet stationed at Port Royal, S. C. In 1863 he became Superintendent of the Albany and Boston copper-mine, in the Lake Superior region, where he was also connected with the earliest development of the Calumet and Hecla property. In 1867 he became the First Assistant Geologist in Clarence King's famous Exploration of

Jan 1, 1909

By J. B. A. Solar Menéndez, M. A. Martínez Fidalgo, L. A. Alvarez-Santullano

1. ANTECEDENTS This present communication refers to the results of the research project entitled "Training in the correct use of chemical oxygen self rescue apparatus and also an analysis of apparatus autonomy", carried out under the auspices of the Specific Collaboration Agreement signed between the Industry Council of the Principality of Asturias (Spain) and INSALUD (National Silicosis Institute, Spain). The antecedents of this project lie in work undertaken by the National Silicosis Institute aimed at optimising efficiency in the use of chemical oxygen self rescuers through improvements in worker training. To be precise, by means of Agreements drawn up between the above-mentioned parties, a simulator was designed and incorporated as the basis of a training station within the " Fundación Barredo" of the Industry Council of the Principality of Asturias. This has been operative since the year 2001 and, up to the present, 2300 Asturian coal mine workers have been trained there. What prompted this activity was the observation of various errors in the use of the self rescuers, deriving from their innate characteristics, especially with respect to the sensation of discomfort - the high temperature and humidity of the breathed oxygen, resistance and inconvenience - and limited autonomy. It was precisely this insight that, in critical situations, lack of familiarity with the conditions of discomfort likely to be experienced during the evacuation process might lead to rejection of the equipment, with fatal consequences, that has justified the setting up of this training and simulation centre. The centre is able to provide all mine workers with the necessary training, and experience of the characteristic sensations experienced when using such equipment (Fig.. 1).

Jan 1, 2003

By G. W. Zhang, Changsha Research Institute of Mining and Metallurgy, X. Xiao, Y. Long, L. L. Huang

"The paper presents a scale-up and design method of vertical screw stirred mill, in which the closed circuit of mill and hydrocyclone was assumed as one factor, theoretically regardless the affects inside system of the mill and hydrocylone. The specific energy is chosen as a scale-up criterion, based on the premise that when fed the same feed material, mills of different sizes delivering the same specific energy will yield products.Batch grinding tests are conducted to determine the specific energy, and combined with industrial production data, scale-up and design of vertical screw stirred mill for industrial production are accomplished. Having developed this method for the vertical screw stirred mill used in regrinding duty of iron ore in Ma Steel, it has now been successfully applied in other installations.INTRODUCTIONThe Towermill was developed in Japan in the 1950s, by the Tower Mill Kubota Corporation, it was fine and ultra-fine grinding mill of the metallic ores and concentrates. Due to the rapid development of metal mining and useful minerals disseminated fine, fine grinding and ultrafine grinding equipment has also been more wide used in minerals processing industry. Typical fine and ultra-fine grinding mil are the Vertimill and Stirred Media Detritor (SMD) Mill of Metso, Eirich Towemill, Outotec HIGmill, FLSmidth VXPmill, Xstrata Isamill and the vertical screw stirred mill (JM) of CRIMM, etc.JM series of vertical screw stirred mill were invented by Changsha Research Institute of Mining and Metallurgy in the 1980s. Energy saving and consumption reducing have been achieved through the optimization and engineering practice. More than 500 units JM series of vertical screw stirred mill are used in the iron ore, copper ore, copper-molybdenum ore, molybdenum ore, Pb-Zn ore and Au ore."

Jan 1, 2016

By AIME AIME

WHEN the War Production Board issued its order which will end the use of iron and steel in more than 400 familiar civilian articles, the list of those products formed a fascinating and homeric catalogue of the things we use. Articles for which iron and steel may not be used after a 90-day "tapering-off" period are as workaday as office machinery and as frivolous as cocktail shakers. Mostly they are smaller items-the smallest probably are phonograph needles but in the aggregate they will save tremendous quantities of the metal most needed to win the war. In total war there are no trifles. Interesting proof of this lies in the fact that by eliminating manufacture of blackhead squeezers we shall save 110,000 lb. of steel a year. Out of this steel we might have made four 155-mm. field pieces. We might have made a thousand 3-in. trench mortars, 4400 0.30-caliber machine guns, 55 16-in. shells, 110 200-lb. aerial bombs, or three 15-ton tanks with something left over to arm them.

Jan 1, 1942

By W. D. Klopp, R. I. Jaffee, H. R. Ogden, D. J. Maykuth

The purification of commercial-purity tantalum powder by vacuum sintering in the temperature range 2600° to 2860°C has been investigated. Mixtures of tantalum oxide and tantalum carbide were sintered at 1800° and 2200°C. Tantalum bars containing 1 pct additions of oxygen, nitrogen, and carbon. were sintered in the range 1800° to 2600°C. Anulyses were conducted on the sititeyed mixtures to determine the extent of removal of oxygen, nitrogen, and carbon at each sintering condition. The mechanism for remova1 of each impurity, and the conditions necessary for preparing ductile tantalum by vacuum sintering are discussed. INTEREST in the refractory metals has been stimulated in recent years by the need for structural materials capable of operating at temperatures of 1100°C and higher. These metals include columbium (niobium) (mp 2468°C), molybdenum (mp 2620°C), tantalum (mp 2996°C), rhenium (mp 3160°C), and tung- sten (mp 3415°C). In addition to its high melting point, tantalum possesses the advantages of forming a solid, nonvolatile oxide at temperatures of interest and of being ductile and easy to fabricate. The classic method of consolidating tantalum from powder refined from the ores is by vacuum sintering at temperatures on the order of 2600°C. This sintering treatment both densifies the compacted powder bars and purifies the metal by causing impurities to boil out. The present work was undertaken to provide more quantative data on the relationship between sintering conditions and purity and to determine the mechanisms of impurity removal.

Jan 1, 1961

By R. R. Van Valkenburch

IT has always seemed to me that mining methods are inventions that follow necessity. I have yet, to be connected with a property where the consultant who has been engaged has laid out a mining method that has been strictly adhered to through the life of the mine. Possibly there are exceptions. As a general rule, perhaps, the method becomes the result of sad experience. I suppose if a person were to attempt to measure the tendency to get away from shrinkage stoping, he would need to send out a questionnaire and expect to receive truthful answers, and, having compiled the results, I think we would find that throughout the country there would be but few cases where present value of product permits the old original so-called shrinkage method to be followed. The method that I had hoped to hear Mr. Fozard expound is strictly an adaptation of shrinkage. Cav-ings do not enter. It was developed by Mr. Fozard and his staff at the Beatson mine of the Kennecott Copper Corp., at, Latouche, Alaska. Stephen Birch, in the TRANSACTIONS in 1923, submitted a brief paper on the mining at Beatson. He stated that a new adaptation of shrinkage was being tried because, although at sur-face the copper .content had been relatively high, at lower levels, in the mine it had decreased.

Jan 5, 1927

By Michael Hoch

The phase diagrams of binary systems of some of the transition elements of Groups IV, V, and VI were used to compute the partial free energies of these elements and the free energy of formation of their Laves-type compounds. From these data, isothermal sections of ternary phase diagrams were calculated and compared with experimental results. DURING the investigation of ternary and quaternary high temperature systems formed by the transition elements of Groups IV, V and VI, the binary phase diagrams for these elements available in the literature were studied. In this study, the free energies of formation of the compounds formed in these binary systems were calculated; these values were then used to determine the general shape of the ternary and quaternary phase diagrams. Above 900°C, the transition elements of Groups IV, V, and VI are all bcc and form only Laves-type compounds in binary systems. The investigation was based on the binary phase diagrams published by Hansen.1 The Cr-Nb system was constructed from the data of Elyutin and Funke.' Several unpublished phase diagrams were taken from Schmidt'sLo and English'sl1 compilations. THE BINARY SYSTEMS valuations of the Thermodynamic Functions. Rostokers evaluated the boundaries of the (a + b) field in Ti-base alloys with a two-constant equation. The authors' interest is mainly in the center of the diagrams; therefore the miscibility gaps in the Zr-Nb, W-Cr, Ta-Zr, Ta-Hf, and Ti-W systems were used to evaluate the thermodynamic behavior of the binary systems. Lumsden's4 Equations 29.2, 32.1, and 33.1, page 287, were used for the excess integral free energy FeX, and for the excess partial free energies Fx and replaces b and b replacesP in Lumsden's notation):

Jan 1, 1962

By J. B. Evans

Maintaining overall optimum profitability at a mine site necessitates constant reassessment of operating strategies. In essence, each strategy is a particular combination of envisaged capital expenditure, income flow and elapsed time. Selecting a strategy, based on profita¬bility potential requires each contemplated strategy being subjected to discounted cash flow analysis; even with a computer such analysis can be cumbersome. The chapter discusses a 'shortcut' technique which assigns profitability rankings to alternate strategies and iden¬tifies those aspects of a. strategy which impact heavily on profitabil¬ity. This technique can yield quick assessments of sufficient accuracy for many operating strategy decisions. taken on site at on-going mines.

Jan 1, 1978

By Keith E. Forrester

This paper presents results of bench scale laboratory evaluation of a processes developed by FESI and Brookhaven National Laboratories for the extraction and recovery of Pb and other heavy metals from incinerator ash which was subsequently modified by FESI for the extraction and recovery of Pb from soils excavated from a FESI client scrap yard and battery breaking operation facility. The specific waste matrix presented within the paper is a battery acid contaminated surficial soil at 0" to 12" depth. The extraction method was found to be highly successful on the bench scale in generating a final post-extracted soil matrix which passed TCLP Pb regulatory limits and retained minimal Pb after aggressive extraction application. The paper findings at this time are brief, as a majority of the research results are currently being compiled and additional efforts are underway based upon initial screening findings.

Jan 1, 1995

By D. E. Piggott, B. E. Hartmann

The thought of constructing an intake shaft five miles from the shore and 142 feet below the surface of Lake Huron from the bottom up sounds like a questionable venture. Why would one want to raise a shaft from the bottom at the end of a 16 foot diameter, six mile long tunnel to within six feet of the bottom of Lake Huron? The answer lies in the fact that Lake Huron is seldom a tranquil lake. The construction period and workable days from the surface are limited. Two previous attempts to construct this intake shaft by conventional means had been thwarted by lake storms. These approaches were circular sheet-piling cofferdams with the intention of sinking a 30 foot OD, five foot wall thickness concrete casing in the center. However lake storms, particularly in the months of November and December, proved disasterous. The last attempt was halted in December 1970 when three of the seven circular cofferdams on the north side were destroyed by pounding waves. Then, due to the nature of the technical difficulties and limited construction schedule time, it seemed desirable to devise a way in which construction could proceed without being too lake-sensitive. Obviously, if men could work from the tunnel and proceed upward toward the bottom of the lake, not having to worry about the soil collapsing and bringing the lake in on their heads, the construction would be unimpeded by adverse weather. The answer to this, however, required techniques beyond the ordinary. Approximately two years previous to the start of this shaft, nine shafts had been efficiently constructed on the same project site

Jan 1, 1974

By Lester A. D. Chin

The cost of bauxite is a multiple of the Bauxite Consumption Factor and the Unit Cost of Bauxite, and is a major cost item at most alumina plants. Bauxite Consumption Factor can be reduced by increasing alumina recovery during processing. Unrecovered aluminas are analyzed and possible research identified, using the framework below: 1. [Unextracted Aluminas] 1.1 Aluminous goethite 1.2 Boehmitic alumina 1.3 Diasporic aluminas 2. [Chemically-Bound Aluminas] 2.1 Desilication product 2.2 Phosphorus precipitate 2.3 Solid-phase lime-reaction products 3. [Alumina Reprecipitated on Red Mud] 3.1 Red mud separation and washing 4. [Physical Loss] 4.1 Liquor 4.2 Alumina dust

Jan 1, 1984

By P. A. Plunkert, D. E. Morse, L. McCartan, S. F. Sibley

The average annual growth rate of real gross domes-tic product (GDP) from the third quarter of 2001through the second quarter of 2003 in the United States was about 2.6 percent. GDP growth rates in the third and fourth quarters of 2003 were about 8 percent and 4 percent, respectively. Many other indicators reflected a rebounding U.S. economy — rising consumer confidence, higher retail sales, greater industrial production and more housing starts. Inflation also reached a 38-year low in 2003. The upward trends in many sectors of the U.S. economy in 2003, however, were shared by few of the mineral materials industries. Annual output declined inmost non fuel mining and mineral processing industries, although there was an upward turn toward yearend as prices began to increase (Table 1).

Jan 1, 2004

By Mark S. Stagg, David E. Siskind

Five major environmental effects of rock blasting are ground vibrations, airblast, flyrock, dust and fumes. What makes them "environmental" as opposed to occupational health and safety issues is that their impacts are felt off the mine, quarry or construction site. For some impacts, safe zones are defined through experience, flyrock being a good example. Flyrock at a mine can be 1) rock thrown beyond the blast area or expected hazard zone, 2) rock thrown beyond the permit area, or 3) rock thrown more than 1/2 the distance to the nearest non-mine structure (OSM rule for surface coal mines). Rock throw of less than the "flyrock" range is then a safety issue.

Jan 1, 1997

By Xingtian Hui

Due to variation in the geological natures of underground coal mines, especially when the entry?s roof/floor are soft and weak, it is vital to select an appropriate roof bolting system to ensure entry stability, coal production, and miner?s safety. No single type of roof bolting system perfectly fits for various types of openings, even within a mine. From the results of continuous research on roof bolting in the past 10 years, the authors used a novel concept of ?Self-screwed? mechanism to develop five types of roof bolting under a patented Self-screwed Tube Bolting System (STBS)©. This roof tube bolting system can be applied to meet different timing-strength requirements under varying mining conditions to increases the stability of mine workings. This paper outlines the structures and mechanisms of the five types of self-screwed roof bolting systems along with their unique characteristics, advantages and disadvantages, and limitations. Two case studies using a Self-screwed Tube Drilling Bolting (STDB)©, one of the five types of roof tube bolting systems, show the principles of mechanics, suitability and parameters for a mine entry and a subway?s construction/ supports in the surrounding soil layers and soft sands, respectively are presented. The results confirmed the time dependent anchorage capacity between predictions and on-site measurements. Currently, other types of the self-screwed tube bolting systems are also being applied to different coal mines in China to increase entry stability and meet safety requirements.

Jan 1, 2009

By John L. JR. Schroder

INTRODUCTION-SYSTEM DESIGN The design of an underground mining operation requires the integration of transportation, ventilation, ground control, and mining methods to form a system which provides the highest possible degree of safety for mine personnel; the lowest cost per ton of product; the most suitable quality of final product, considering its intended use; the maximum percent recovery of the reserve, consistent with cost and subsidence rights ; and the minimum disturbance to the environment. The selection of mining method is generally the controlling factor in overall mine design. Some important considerations in the choice of mining method are : 1) Depth of cover over the coal seam. 2) Strength and thickness of rock strata in the overburden. 3) Characteristics of the coal seam, including thickness, nature and location of impurities or irregularities, dip (or pitch), nature and direction of cleavage, hardness, and structural strength of the coal. 4) Nature and strength of the immediate roof (top) over the coal seam. 5) Nature and strength of the floor (bottom) under the coal seam. 6) Presence and amount of explosive gas (methane). 7) Quantity of water likely to be encountered in the mining operation. 8) Any previous or concurrent mining in seams above or below the coal seam to be worked. 9) Any restrictions on recovery required for subsidence control. Topographical and geological reports and maps of the area are usually available from state and federal geological surveys, and contain excellent general information to guide more detailed investigations. Exploratory drilling, and the plotting and analysis of the information thus obtained, are essential steps in any development program, and aid in the correlation and evaluation of information gained by other means. Other good sources of information are operating coal mines that may be in the same

Jan 1, 1981

W. H. LINNEY, Chairman, OSCAR LACHMUND, Vice-Chairman LYNDON K. ARMSTRONG, Secretary-Treasurer, P. O. Drawer 2154; Spokane, Wash. STANLY A. EASTON, S. SHEDD. Mining camps from Mexico to Alaska and from the Pacific coast to the Atlantic were represented by delegates at the 5th Annual Northwest Mining Convention which was held in Spokane, Wash., Feb. 19-24, 1917. About 300 delegates from outlying regions were present, this being fully 100 more than have been counted at any previous mining convention in Spokane. Graham B. Dennis, president of the Northwest Mining Association, made the address of welcome. In part, he said: "Heaven has made us the possessors of an area great enough for an empire, varied enough in climate and possibilities to compass the whole complex field of modern industry. In the development of this broad heritage, we are not only actors for today, but trustees for future ages. "It is to foster this spirit of unity; to create and maintain strong bonds of mutual good will and confidence, that we founded the Northwest Mining Association. Wee support it because we believe it will give us strength; because we believe we shall learn from each other; because, in industry as in every other walk of life, personal contact and establishment of ties of friendship enrich and round out the characters of men." One of the interesting lectures of the week was that on "Alaskan and Russian Gravel Mining," by Dr.' Henry Mace Payne, consulting engineer for the Russian government and Consolidated Goldfields of South Africa. Dr. Payne's illustrations showed the different appliances in use in the countries mentioned. The Resolutions Committee reported back to the Convention six of the seven resolutions that had been presented to it. These were adopted as submitted, with some minor changes.

Jan 5, 1917