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By Dean Bray

During the past three years, a new rear-dumping dragline bucket technology has been patented, developed and tested at North Dakota coal mines. Field testing has shown that this new concept in dragline bucket technology can improve strip-mining efficiencies by reducing cycletimes and increasing dumping radius. This article details the process, participants and the results for the development of a rear-dumping dragline bucket. Participants in the process In November 1995, the board of directors of Dakota Coal authorized the execution of a field test and option agreement and a license agreement with the partnership of D.F. Schmidt, electrical/maintenance supervisor, and Bill Lengenfelder, president of Modern Industrial. The board also authorized entering into a dragline bucket field-testing agreement with the Falkirk Mining Co.

Jan 1, 1999

By Oliver Bowles

The term" sandstone" is applied to a rock composed of mineral grains smaller than pebbles, cemented together more or less firmly. "Conglomerate" is the name given to a rock composed of pebbles, or pebbles and bowlders, of various sizes cemented together. If the pebbles are large and well rounded the rock is sometimes called " pudding stone." Although the term "sandstone" includes all varieties, certain specific terms are applied to types characterized by particular compositions, colors, or uses. "Quartzite" is a variety in which the individual grains are so firmly cemented together with quartz that the rock will fracture as easily through the grains as through the cement; "ferruginous sandstone" is one rich in iron as cementing material, or as grains, or both; "micaceous sandstone" is one in which mica is prominent; " arkose" is a feldspathic or granitic sandstone composed of angular grains; "calcareous sandstone" is one containing considerable calcium carbonate; and" argillaceous sandstone" is one containing considerable clay. The term "flagstone" is used for a rock that splits readily into sheets suitable for flagging; "freestone" for rock than can be cut or carved readily, and with equal ease in all directions; and" ganistel'," in the United States, for sandstone suitable for the manufacture of refractories. Others are named from their characteristic colors such as " bluestone," " redstone," or " brownstone."

Jan 1, 1917

By Y. H. Cheng, D. M. Lewis, V. Castranova, M. W. Barger, J. K. H. Ma, J. Y. C. Ma, W. F. Xin

Bis-basic ethers off fluorene and fluoren-9-substituted derivatives such as tilorone have been reported to inhibit silica-induced fibrosis in rats. The potential antifibrotic potency of 2,7-bis (diethylamino) ethixy fluorine fluorenone (F-9-H.H), fluorenoxime (F-9-one), and fluorenol (F-9-ol) was F-9-axime > F-9-one ~ F-9-H,H > F-9-ol. Since the release of reactive oxygen species and growth factors from alveolar macrophages (AM) in response to silica exposure has been linked to the development of pulmonary fibrosis, the present study was carried out to determine the inhibitory effects of these compounds on rat AM activity in vitro. The following parameters were monitored: (1) cellular viability; (2) zymosan-induced respiratory burst activity (superoxide and hydrogen peroxide release, chemiluminescence, and oxygen consumption) of AM; (3) drug binding to AM; and (4) lipopolysaccharide (LPS)-stimulated interleukin- I (IL-1) release from AM. The bis-basic ethers, at 40 did not affect cell viability when incubated with AM for 30 min, but significantly inhibited zymosan-induced macrophage respiratory burst activity. The inhibitory effect of these agents was F-9-oxime > F-9-one ~F-9-H,H > F-9-ol. Binding of these drugs to AM was time and dose dependent, and exhibited the following binding affinity: F-9-oxime > F-9-one > F-9-H,H > F-9-ol. F-9- oxime was shown to inhibit LPS-stimulated IL-I release by AM in a dose-dependent manner. This inhibition of IL-1 release by AM cannot be explained as a decrease in viability. In addition, these drugs were also shown to impair human fibroblast proliferation in response to serum stimuli without impairing cell viability. These results indicate a positive correlation between drug binding to AM or other cell types and their inhibitory effects on cellular activities including oxygen consumption, superoxide release, hydrogen peroxide secretion, chemiluminescence, IL-I release, and proliferation. The ability of-these bis-basic ethers to modify AM and fibroblast functions in vitro suggests that further investigation of their reported antifibrotic potency in vivo is warranted.

Dec 1, 1996

By Hoskings R

Conceptual studies of the run of mine stockpiling and reclaiming requirements at Thiess Bros Pty Ltd South Blackwater coal mine commenced in 1975.Final selection of equipment was made in 1978 and the equipment was commissioncd in June 1979. Equipment selection was made after extensive investigation and visits to existing facilities throughout the world.The equipment selected is described and compared with the alternatives. Foundations were designed to minimise clean up effort and to ensure stabilily of equipment under design wind loading without storm bays. Programmable logic control enables the stacking and reclaiming facility to provide a blended feed to the coal preparation plant.

Jan 1, 1981

By William W. Odell

Certain gas-making processes are in use in Europe, particularly in Germany, which differ radically from those in common use in America. A number of them are of particular interest because they are different. The questions naturally arise: Are any of them applicable to the making of gas in this country and, if so, with what particular type of solid fuel? It is a fact that some of them were developed with consideration of a particular set of conditions and for the utilization of solid fuels available in Germany. The latter fuels, in certain characteristics, are unlike the high-rank fuels commonly used for making gas in the United States; therefore, in attempting to evaluate the various foreign- developed processes with regard to usefulness here, one must give attention to the particular conditions that will prevail in any specified case and also the characteristics and requirements of the process and generator under considera- tion. Three of the processes that were developed and put into commercial operation in Germany, and which have some characteristics in common, are con- sidered in particular in this publication; they are: 1. Lurgi pressure gasification process. 2. Winkler process. 3. The Leuna slagging-type producer-gas process. Each of these processes requires steam and oxygen as gas-maiding fluids. For a number of years, oxygen, has been used in a relatively pure state,. along with steam, in making gas in Germany, and many of the difficulties initi-. ally encountered have been overcome. Although it appears that oxygen recovered from air was first used in this manner as a method of utilizing a byproduct in a plant that used the nitrogen complement in the manufacture of ammonia; more recently, the oxygen was made particularly for the purpose. The fuels - brown coal or lignite used in processes 1 and 2 were not suitable for use in the older and commonly used intermittent-type water-gas generators, and it was necessary, therefore, to devise a different process for gasifying them. A gas of higher heating value than producer gas, was desired, and the use of oxygen (not air) along with steam made possible the production of the desired gas without nitrogen dilution, which characterizes producer gas. Operating data presented herein are based upon observations by, members of the Technical Oil Mission at plants in Germany, on records, and on information vocally given to members of the lässion, including the author, while visiting those plants, and they are believed to be reasonably correct; however, certain hasic observations, comparisons, and conclusions are. made by the author.

Nov 1, 1947

The 28th annual American Mining Hall of Fame Awards Banquet and fundraiser sponsored by the Mining Foundation of the Southwest will be held at the Marriott University Park Hotel, Tucson, AZ on Saturday, Dec. 4, 2010. The Mining Foundation of the Southwest is a nonprofit organization whose objectives are public education about the mineral industries, and recognition of outstanding accomplishments in and contributions to the fields of mineral and fuel resources. Funds are being raised to the support the foundation?s educational programs. Among these is the Educational Outreach Program operated jointly by the foundation and the Arizona Department of Mines and Mineral Resources.

Jan 1, 2010

By David K. Hylbert

This study investigated stratigraphic and structural causes of roof falls in room-and-pillar drift coal mines in nine mines in eastern Kentucky. A contract modification provided for remote sensing studies in the Dunkard Basin of West Virginia and Pennsylvania. Results of stratigraphic and structural studies of an earlier contract (H0133018) were applied to several new mines. It was found that similar rock sequences contributed to unstable roof conditions. Structure contour and isopach maps were found useful In projecting these trends together with fence diagrams. Using Landsat imagery, a direct relationship was found between lineament direction and the trends of rock jointing, roof fall zones, "snap top" zones and sandstone channels in the examples cited. It was found that, by analyzing lineament intersections, from 50 percent to 65 percent coincided with roof falls.

Jan 1, 1980

By Karl Oltay

A series of 15, stations beginning with Potsdam and Budapest and ending with Budapest and Potsdam were occupied inn the period August, 1908, to January, 1909. The intermediate stations were all at points which had been connected by Baron Eötvös with torsion-balance traverses. The observations were made with an invariable pendulum of the standard four-pendulum type of instrument of the Geodetic Institute, made by Stückrath at Berlin-Friedenau. The observations at each of the field stations lasted-one to three days with one exception; two or three time determinations were made; four to eight series of pendulum observations were made; the error of determination of the elevation of the instrument above mean sea level ranged from 0.30 meter to 1.10 meters, with the exception of the Arad and Baja stations, where the elevation was known more accurately and averaged about ± 0.8 m, which would cause an error of ± 0.25 x 10-3 dynes. No topographic correction was applied. The values for ?g were taken from Eötvös: Report on Geodetic Observations in Hungary, especially Observations with the Torsion Balance, Budapest, 1910. The differences in ?g as determined, by the torsion balance and by the unvariable pendulum were: Kuvin-Hidegkut 1.2 km. 0.001, Livada-Kuvin 9 km. 0.001, Pankota-Livada 13 km. 0.004, Kuvin-Arad 20 km. 0.000, Pankota-Arad via Kuvin 42 42 km.0.005, Pankota- Arad via Kurtics 50 km.0.000 dynes. Oltay concludes that if the stations are close enough together and if the terrane is rather flat, the measurement of ?g with the Eötvös torsion balance is as accurate as with the invariable pendulum. -- Donald C. Barton.

Jan 1, 1929

By Hal J. Kelly

A number of problems that developed in processing the halloysitic clays of eastern Washington and northern Idaho were investigated by the Bureau of Mines. The deflocculating effect of tetra sodium pyrophosphate is compared with several other compounds, and on the basis of current theory, the advantage of sodium pyrophosphate as a deflocculating agent is explained. The adsorption of the sodium ion by clay in a clay"-water system was established by a radioactive tracer technique, and the deflocculating action of sodium pyro- phosphate was postulated. The effective dispersion of the halloysitic clays was limited by the occurrence of tightly bound aggregates of small, individual crystals. Disaggregation of the agglomerates was investigated by liquid extrusion and ball milling of dilute slurries and by extrusion of the clay in a plastic state. The greatest increase in the production of small particles was by high? pressure liquid extrusion.

Jan 1, 1963

By Mark Fernald, Christian O’Keefe, John Viega

"In this presentation, the SONARtrac™ technology platform will be described. CiDRA's proprietary clamp-on, passive sonar array-based flow meter technology performs two independent measurements – flow rate and fluid characterization. Firstly, the meter provides the volumetric flow rate of the mixture by measuring the speed at which naturally occurring turbulent structures convect with the flow past an axial array of sensors. Secondly, the meter uses similar sonar-based processing techniques and naturally occurring sound in the process fluid to measure entrained air levels. The result is a unique ability to measure the flow rate and entrained air level of most fluids – clean liquids, high solids content slurries, and liquids and slurries with entrained air.Also to be presented is the application of the sonar-based technology platform in a variety of oil sands processes, hydrotransport, and minerals beneficiation applications. In particular, difficult slurry flow measurement and control in the areas of comminution and flotation such as mill discharge, hydrocyclone feed/overflow, final concentrate, thickener discharge, and tailings will be discussed. In addition new real time maintenance free process measurement capability will be presented in the areas of entrained air in slurry, collection zone gas holdup (?g), and slurry velocity profiling. The operational advantages and value of these measurements, even in the presence of scale buildup, will be discussed.INTRODUCTIONFlow measurements in the mineral processing and oil sands industry suffer from the limitations placed by previously available flowmeters including the commonly used instruments such as ultrasonic meters, magmeters, turbine meters, orifice plate meters, vortex flow meters, Coriolis flow meters, and venturi meters. The desire or requirement to make a non-contact measurement that is accurate and robust, and can be performed on practically any type of fluid within practically any type of pipe has driven the creation of a new class of flowmeters. This new class of flowmeter technology utilizes sonar-based processing algorithms and an array of passive sensors to measure not only flow, but also fluid composition."

Jan 1, 2007

Cement in 1975 indeed did operate in an unfriendly environment. World recession, escalating costs, fuel crises, reduced product demand . . . . all led to market conditions detrimental to industry profit margins and investment re turns. During the year plant utilizations fell, break-even points were raised, and competitive moves introduced to move built up inventory levels. A number of cement plants were temporarily taken out of production to help alleviate specific situations. Meanwhile, under resultant financial pressure, several companies omitted dividend payments, changed their top executives, and reorganized and reduced staff overheads. It was a difficult year for cement, yet a much more ominous note was sounded in permanent plant closings. Four more cement operations were shut down in 1975; to date in 1976 we know for sure of three additional plant closings, while rumour has it that at least one more may not be in production by year-end. The somber feature is found within the descriptions of the closed facilities, and in the stated reasons for their being taken out of cement manufacture.

Jan 1, 1976

By Richard B. Stein

Section 25 has been assembled to give the geological, mining, or metallurgical engineer an overview of some of the important downstream operations that typically follow mining activities. This subject is obviously too broad and complex to be covered in detail within this Handbook. However, the engineer will be interested to learn about the basic fundamentals, and especially how they might affect the economics of the total project from prospecting and mining through to metals recovery and marketing. In this way, it is hoped that the engineer will have a better overall appreciation for the technical and commercial prospects of a mining and metal-producing project.

Jan 1, 2008

Organization Place Date 1919 American Electrochemical Society New York, N. Y. Apr. 3-5 American Chemical Society Buffalo, N. Y. Apr. 8-11 National Foreign Trade Council : Chicago, Ill. Apr. 24-26 American Iron and Steel Institute New York, N. Y: May American Institute of Electrical Engineers Lake Placid, N. Y. June 23-27 American Society for Testing Materials..: Atlantic City, N. J. June 24-27 American Railway Bridge and Building Association Cleveland, O. Oct. 21-23

Jan 4, 1919

By Frank R. Field, Randolph E. Kirchain, Elisa Alonso

"There are a number of environmental incentives for increasing recycling, including the reduction of waste, energy and resource use. Recycling can also be advantageous for manufacturing firms in both the short and long term. Secondary material can substitute for primary material, potentially dampening primary material price increases and reducing the pressure for greater primary extraction. This paper examines the potential for and dynamics of recycling for the case of platinum using a dynamic, behavioral simulation model of the primary and secondary markets. Since the secondary supply of platinum depends on a supply chain separate from primary extraction, recycling can diversify the risks of primary supply instabilities. Over time, recycling can cut primary consumption, reduce overall costs to firms, and possibly reduce the impact of price fluctuations upon firms.IntroductionThe benefits of recycling, from the perspective of the environment, are many, and the environmental benefits of increased recycling are considered a step towards increased sustainability [1, 2]. Life cycle assessments indicate that obtaining materials from secondary sources generally requires less energy and has fewer environmental impacts than extraction and refining of primary materials [3]. Analyses of materials flows show that, in addition to landfill volume reduction, recycling reduces primary material consumption, affecting long term materials scarcity [4, 5].The benefits of recycling are not limited to the environmental. Firms can benefit from the lower energy costs of recycling, especially that of metals whose primary extraction and refining are particularly energy-intensive (e.g., aluminum). The routine participation by firms in secondary materials markets (e.g., www.recycle.net) shows that this advantage has not gone unnoticed.Recycling can also benefit firms whose costs can be significantly affected by changes in material prices resulting from material shortages and material scarcity, with potentially permanent effects upon firms [6-8]. This paper focuses on the impact of recycling in the face of platinum scarcity for supply chain downstream firms."

Jan 1, 2008

By B. H. Moore

Foundation and excavation problems associated with lock construction projects vary widely. Each lock requires a different foundation to respond to a unique geologic setting. The range of heights and founding materials are illustrated thru description of selected structures encountered in the United States. Examples range from 113-ft high John Day Lock on the Columbia River founded on basalt rock to the 17-ft high Lock No. 5 on the Arkansas River floated on a clay foundation. A description of the basic elements of design and construction is presented. Several case histories involving lock design and construction are assessed to aid in recognition of potential problem areas on forthcoming construction. In the past decade there have been many improvements in construction materials and techniques. The application of these new approaches to lock construction is discussed.

Jan 1, 2010

By F. Habashi

Japan was a closed society until 1853 when it was forced to open to the West. Mining, metallurgical, and geological education started there around 1861 when a graduate from Yale University in USA went to Japan to organize the first School of Mines. This was followed by other metallurgists from Great Britain, France, and Germany and thousands from other disciplines. The present report is a summary of the writer's first contact with Japanese metallurgists and his visits to a number of universities and research institutions in the past years.

Jan 1, 2012

By A. M. Tunstall

Aspects of blast vibrations, damage mechanisms and the influence of rock quality on damage severity are reviewed and results presented from a monitoring programme in which the rock mass rating for six tunnels was determined. The peak particle velocity induced in the tunnels during open-pit blasting was measured and the tunnels were inspected visually for fresh damage after each blast. The results suggest that the quality of rock in which an excavation is situated has an influence on the level of ground vibration to which it can be subjected without sustaining damage. This means that the use of a single limiting value of peak particle velocity, as in the blast damage criteria for residential structures, is not ideal and may result in damage to excavations in poorer-quality rock masses

Jun 19, 1905

By Z. Xiao, A. R. Laplante

"The recovery of gold by gravity from grinding circuits differs from virtually all other gravity recovery approaches in that stage (or unit) recoveries are low, typically 1 to 5%, but overall recoveries are generally in the 25 to 60% range, because individual gold particles are presented many times to the primary recovery unit. Full-scale recovery is difficult to predict from benchscale tests. Further, maximizing metallurgical recovery is generally not the primary objective, because of the more efficient downstream recovery circuit (flotation or cyanidation). In this paper, a new concept, the gravity recovery effort, is presented to assist in the design and optimization of gold gravity circuits. It is defined as the product of the circulating load treated by the primary gravity unit, the recovery of this unit, and the gold room recovery. Predicted gold recovery is linked to the recovery effort, the size distribution of gravity recoverable gold (GRG), the dimensionless retention time in the mill and the partition curve of GRG. A case study of economic optimization of the gravity recovery effort is presented. INTRODUCTIONPredicting gold gravity recovery from grinding circuits has always been a hit-and-miss exercise. The problem can be traced to the highly variable gravity recoverable gold (GRG) content of ores, high GRG circulating load, fraction of the circulating load treated, and performance of primary gravity recovery and gold room. Typical values, highs and lows are shown in Table 1."

Jan 1, 2001

By Jonas Olsson

"The picture of China as an antiquated continent is changing rapidly and fast-forwarding progress is a fact in most infrastructural fields. Mining is not an exception. China is today the largest producer of aluminum, coal, steel, zinc, tin, lead and manganese and the country’s mineral resources comprising approximately 12% of the global reserves ranks them number three in the world after US and Russia.In order to feed the growth industry is needed to take extra ordinary strides to improve supply of raw material and Chinese mines are continuously being upgraded with the latest western technology to meet the increasing domestic demand of base metals.In Anshan located in China’s northeast province Liaoning we find one of the fastest developing mining companies, Angang Iron & Steel Group Co. Ltd. With their six mines that together process approximately 60 M ton iron ore/year Angang Iron & Steel Group Co. Ltd is the largest iron ore company in China. The group’s thorough pre-studies and technical evaluations over the past five years have made them very successful in both plant upgrades of existing operations and green field projects.INTRODUCTIONWe live in a time when the world market is gradually acclimatising to the global consequences of “The China effect”. An effect caused by a formerly sleeping giant nation that during the last years has awakened and developed beyond comparison, primarily because of booming infrastructure projects and demand for capital and consumer goods"

Jan 1, 2006

By JOHN W. KOSTER, JAMES R. FLEMING

The following report is made through the Bureau of Mines as a result of the work under the cooperative agreement with the State geological survey and the engineering experiment station of the University of Illinois. It deals with the use of permissible explosives in the coal mines of Illinois, and is intended primarily to present to mining men the possibility of assuring safer conditions in mining through the use of these explosives. Twenty coal mines in Illinois were using these relatively safe explosives at the time this report was prepared. Of these, seventeen were in Franklin County, two were in Saline County, and one in Montgomery County. In these various fields experience had shown that although black blasting powder was a useful agent in breaking down the coal at the working face, yet it had given such conclusive evidence of its danger to life and property in causing explosions and mine fires that a substitute was sought and has been found in permissible explosives. Each coal mine in Illinois in which permissible explosives are used was visited and a study made of the problems involved. The report deals briefly with the dangers of black blasting powder now in such common use in coal mining. It discusses the development of permissible explosives and their introduction into Illinois coal mines and points out the characteristic differences between permissible explosives and black blasting powder. The present system of blasting and the most approved methods of using permissible explosives are described. Data are given to show that not only has safety and efficiency in these mines been greatly improved, but that the cost of explosives to the miner per ton of coal has been reduced, and that sizes of coal produced from permissible explosives compare favorably with those previously obtained at the same mines with black blasting powder. The successful use of permissible explosives in these Illinois mines as well as in many other mines throughout the country should aid in their introduction into a larger number of mines and bring about that degree of freedom from explosions and fires which should be attained in mining.

Jan 1, 1917