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By Tom Pfitzer, Alice Correa, Meredith Hardwick

The past decade has brought significant changes in the use of risk-based criteria for safety within the U.S. Department of Defense. The Range Commanders Council (RCC) chartered a working group to develop and define risk acceptance criteria for protecting the general public and mission essential personnel from debris from launch ranges. This working group has continued to develop and update RCC Standard 321 as the needs of the ranges and range users have evolved. A revision to RCC Standard 321 is near finalization and will include casualty criteria, guidelines for assessing risks due to other flight hazards in addition to inert debris, and an overall risk management process for range safety. This paper reports on work in progress and includes several precedents which may prove important to the explosives safety community.

Jan 1, 2007

By F. B. Waanders

Coal, as energy resource, possesses numerous characteristics and properties which all have an influence on its gasification behaviour. The two properties considered as critically important when evaluating a coal source for gasification is its mineral content and slagging behaviour. Research has indicated that slagging formation can be inhibited or even prevented by the addition of a fluxing agent. It is thus of great importance to understand the mineral interaction during gasification in order to select a suitable fluxing agent for the prevention of slagging and clinker formation in the gasifier. The aim of the present project is to evaluate the effect of iron as a fluxing agent and study the transformation of the mineral and added iron during gasification. A pre-determined amount of pure elemental iron (between 2wt% and 20wt%) was added to a base case coal sample in order to study the effect of the addition of iron to the coal. The transformation of the iron in conjunction with the possible iron containing minerals present in the coal was studied by means of Mössbauer analyses. Typical characterisation techniques included proximate analyses, ultimate analyses and ash composition analyses. The ash fusion temperature analyses (AFT) were used to study and predict the slagging behaviour of the iron-spiked coal samples. Even though AFT analyses only provide an average flow property, it gives a good indication of the changes that the iron addition induces on coal properties. FactSage modelling was carried out in conjunction with the Mössbauer and AFT analyses. From the proximate, ultimate and ash composition analyses it was clear that the coal used con-formed to the average characteristics measured over an extended time period. From the AFT values it was seen that an increase in the flow temperature occurred with the addition of pure elemental iron to the coal, which can be of importance for operational purposes as to raise the gasifier temperature and not to have slagging problems to occur in the gasifier. The Mössbauer data show that he-matite is the main Fe-component that forms from the pyrite originally present and from the added iron to the coal, consistent with FactSage modelling, which shows that the partial oxygen pressure determines which mineral species will form. This study opens up new possibilities when considering operational problems experienced in in-dustrial gasifiers. Successful completion of this study and a study to look at reducing conditions in the gasifier will also add to the knowledge that already exists regarding fluxing agents.

Jan 1, 2014

By Knevitt L. T

PART 1Details of Kiewa Scheme.Introduction.Topography.Preliminary Investigations.Geology.Description of Project.Details of Main Works.Main Transmission of Power.Construction Facilities.PART 2Underground Works.Summary of Projected Works.Administration.Labour.Surveying.Safety and Accident Prevention.Medical Attention and First Aid.PART 3No. 4 Head Race Tunnel.Summary.Geology.

Jan 1, 1950

By TENNEY C. DeSOLLAR

TRADITION tells us that the earliest use of Alabama iron was to make shoes for the horses of General Andrew Jackson and his men during the first part of the nineteenth century. The first recorded incident in the making of iron was the request of U. S. Indian Agent Benjamin Hawkins "that a crew of blacksmiths be sent to the Creek Nation in the lower Mississippi territory." These frontiersmen made up the first body of pioneer iron makers in the territory. The first known blast furnace was built by Joseph Heslip in 1818 at Russellville, named after Major William Russell, who was General Jackson's chief of scouts. The Tannehill furnace was built in 1830 in what is now Tuscaloosa County and its ruins, as shown above, can be seen today.

Jan 1, 1937

By Felix Edgar Wormser

JUST as the ancients used the products of their crude mining endeavors to fashion tools with which to make digging easier, so today mining enterprises are dependent upon the very metals they mine for the efficient conduct of mining and metallurgical operations. In fact, the outlet afforded by the production of minerals in the United States is no mean market for the nonferrous metals. I believe that mine managers frequently lose sight of the opportunity they have to select from competitive products those which will help the market for their own metal output. For example, some years ago a large lead mine used storage-battery locomotives for its haulage, common practice, of course, throughout the United States. These particular locomotives, however, were powered not with the ordinary lead storage battery but by a competitive battery product made from an imported metal. After studying this situation, the manager saw how he could help himself by purchasing a product made from his own mineral output, and in his next order turned tip the use of the lead storage battery.

Jan 1, 1935

By David E. Thompson

This paper describes the full-scale field load testing of three deep foundation units using the Osterberg Load Cell. The load tests were completed on three separate projects, two in Massachusetts and one in New York. The Massachusetts projects involved the load testing of two 18-inch O.D. concrete-filled steel pipe piles over water for railroad bridge reconstruction projects in Revere and Saugus/Lynn. The New York project involved the load testing of a 24-inch diameter drilled shaft socketed into sandstone on land for a building foundation in Rochester. The 18-inch O.D. piles were loaded to failure at jack pressures of 142 to 215 tons. The drilled shaft was loaded to failure at jack pressures of approximately 450 tons. The loading testing procedure is described and the results of the three tests are presented. The advantages and disadvantages of the Osterberg load cell for load testing of deep foundations are discussed.

Jan 1, 1989

This Bureau of Mines publication summarizes the industrial minerals industry of Idaho. It contains information on 119 principal deposits of 21 commodities in the State and describes the institutional and infrastructural factors affecting mineral development.

Jan 1, 1991

By Raymond B. Ladoo

The uses for which ground talcs are suited closely depend upon their physical and chemical properties , but , in spite of this fact , little scientific investigation has been made in order to devise quick and accurate tests for the determination of these properties . The chemical properties of talc are inherent and may not be altered or modified except by selective mining or by chemical processes not practical in the present status of the industry . However , the determination of chemical properties is not so important , for most uses , as of physical properties , although sometimes certain chemical characteristics are perhaps unduly insisted upon by chemists in some industries . Physical properties are dependent both upon mineralogical characteristics and upon methods of grinding and sizing and may thus be partly changed or modified by changes in practice . There is so little known of the chemistry and physics of the various processes in which talc is used that the purchase and sale of talc is governed more by rule- of- thumb methods dependent upon individual opinion and often , prejudice , than by accurate , standard tests . This not only causes unwarranted price fluctuations , but injures both the producing and consuming industries by creating false ideas of the suitability of talc for various uses . It thus seems important that present tests be standardized and made uniform for the whole industry , and that new tests devised to fill the existing gaps .

Jul 1, 1920

By D. W. Breck

Zeolites were first recognized as a new group of minerals by Cronstedt with the discovery of stilbite in 1756. The word zeolite was coined from the two Greek words meaning "to boil" and "a stone" because of the loss of water when heated in the mineralogist's blowpipe (Breck, 1974). In 1845 it was discovered that certain soils lave the power of retaining ammonium salts Way, 1850). These were the first ion exchange experiments. Later it was discovered that it was the hydrated silicates in the soil that produced this phenomenon. Several years later a paper was published dealing with the action of dilute salt solutions on silicates which showed that this base-exchange principle, which we now call cation exchange, is reversible. The quantitative cation exchange behavior of zeolite minerals, such as chabazite, was studied. As a result any aluminosilicate which exhibited the property of ion exchange was referred to as a "zeolite," even today the term has been applied to clay minerals as well as synthetic organic ion exchange resins.

Jan 1, 1975

By Philip B. Grote

The deep ocean mining industry is in a pre-commercialization stage of development. In the context of a proper legal/regulatory regime, deep ocean mining system design, site survey, and operation technologies are capable of rapid evolution. The report recommends that the regulatory framework develop in parallel with the industry and presents a rationale for implementing this approach. The Government has several interests in deep ocean mining technology: (1) as a potential regulator, sound regulations should be based on an understanding of the technology; (2) as a potential monitor, survey technologies are relevant; and (3) as an estimator of strategic minerals supplies, it is important to understand the technology which allows economic access to deep ocean minerals. Thus, the major portion of the report presents an in-depth review of systems design, operations, and survey equipment and techniques.

Jan 1, 1979

Application of microprocessors, programmable logic devices, and other computer-oriented hardware and software on-board large surface mining equipment to optimize availability and productivity, stretch machine life, and protect against catastrophic breakdown has been a goal of heavy-equipment manufacturers for several years. Progress in this direction has not been as rapid as many manufacturers anticipated in the mid-1980s, and, on the other side of the coin, mining industry and machine operator acceptance of such products has not always been enthusiastic. However, the trend toward such development seems undeniable. Large surface mining equipment in the future will doubtless carry more, and not fewer, applications of computers and computer-related products. The intensity of development interest and degree of progress in commercializing such on-board computer and computer-related products on surface mining equipment varies considerably among the manufacturers. Summarized here are the on-board computer-oriented products of three heavy-equipment suppliers-P&H Harnishfeger, Marathon LeTourneau, and Haulpak not a comprehensive survey, but, perhaps indicative of the direction such development is taking.

Jan 1, 1990

By G. S. Pauley

Paper presented at a meeting on: Artificial intelligence in the minerals sector, held in Nottingham, UK, 20 April 1993 (original title: Case-based reasoning can be a catalyst for improvement). A new computer software technology known as Case Based Reasoning (CBR) can be used to produce small decision support systems that are economically viable. This is because the knowledge that they contain can be owned and maintained by their users. A CBR tool has been used to perform a pilot study with Anglesey Aluminium Metal Ltd. The results are encouraging. They suggest that a combination of CBR and participative design and implementation techniques (such as Checkland's Soft System Methodology) can achieve sustainable improvement in mineral processing functions. An explanation is presented of why traditional, rule based systems are often an ineffective way to implement support systems. It is shown that CBR may provide an appropriate technology solution. Methods of achieving sustainable benefit are indicated. The pilot study with Anglesey Aluminium Metal is used as a practical illustration of the development of a CBR application. A review of potential application areas and some observations about the implementation are presented

Apr 1, 1994

By Edward H. Williams

IN the middle of the eighteenth century John Frazier and wife, Sarah Ingraham, removed from Boston, Mass., to Philadelphia, Pa., where he was held in such esteem that we find him one of the Committee which arranged the ball at Washington's inauguration. Their son John. Nalbro Frazier, was prosperous in his mercantile career and fortunate in his wife, .Anne West; who was an important personage in the early life of Professor Frazier. This cultured lady brought into the family an atmosphere of religious enthusiasm, of thoroughness and: of unity of purpose. Her son, Benjamin West Frazier, inherited her traits and displayed them during a. short and active life. Like his father, he engaged in mercantile pursuits, and was a member of the firm of Zimmerman, Frazier & Co. In their interests he lived for a short- time in Montevideo, and on his return married Isabella Zimmerman, a daughter of the head of the firm. Their happy married life was cut short by the death of Mrs. Frazier shortly after the birth of the subject of this sketch which, occurred October 3, 1841. Mr. Frazier did not long survive her, and left his orphaned sons to, the care of his mother, from whom he had inherited a lovable and deeply religious nature, an : artistic temperament and a capacity for thorough work. Whatever of these traits fell by inheritance to these children were strengthened by the influence of their grandmother, and. the purity of mind, the delicacy of sentiment, the refinement of honor, which characterized. Professor Frazier, are due to Anne West Frazier, and are generally present in the characters of all of gentle blood who have been under the sole and immediate influence of a mature and refined woman. Professor Frazier was educated at the Episcopal Academy in Philadelphia, and passed thence through the University of

Sep 1, 1905

By John Wilson

This report describes the performance of Phase I of a project to design, analyze, and demonstrate a multilift longwall mining method applicable to mining coal seams twelve (12) feet or more in thickness. A non-simultaneous multilift operation is the most viable thick seam mining technique for introduction to the United States coal industry. In the case of the proposed site at Emery, Utah it will result in an increase in coal extraction from 30% with present methods to at least 50% and possibly more. The major technological advance involved in this project is mining a lower lift under a previously mined upper lift. To accomplish this, entries must be developed and maintained beneath the upper lift gob. This will necessitate the use of steel supports at frequent intervals throughout the lower lift' entry system. This has not been done in the U.S. to date. An economic analysis of the project indicates that, while this method will result in a higher than average cost per ton for coal mined, the coal would be competitive with current-operation in the area.

Jan 1, 1976

Failure of rock materials is a process of crack propagation. Crack initiation takes place when the crack tip stress intensity K reaches a critical value called fracture toughness, K1C. The rock fracture toughness is known to be affected by the surrounding environment such as temperature, confining pressure and humidity. In order to examine the effect of humidity, a series of semi-circular bend tests were performed under various water vapour pressures in a rock material that is known to be anisotropic. Water vapour promotes stress corrosion of rock and therefore the fracture toughness was found to have a decreasing trend with increasing water vapour pressure. The rate of decreasing the fracture toughness depends on the microcrack density that promotes the migration of water vapour into the rock. Also in an anisotropic rock, the fracture toughness depends on the direction of crack in relation to the anisotropy of the rock material.

Dec 6, 2010

By C. B. Manula

This report is volume 9 of an eleven-volume final report for a Grant completed by The Pennsylvania State University for the Bureau of Mines to develop a dynamic general purpose computer simulation model for underground coal mining. The simulator developed under the Grant has a wide range of possible applications in the design and evaluation of underground coal mining systems from the standpoints of health and safety, productivity, and mine environment. The Master Design Simulator consists of nine free-standing function-oriented subsystem models linked together into an integrated, comprehensive model of an entire mining system. The subsystems comprising the Master Design Simulator include geology and reserves, methane generation, roof support, subsidence, production, rail haulage, cost, water generation,' and ventilation. This volume of the final report describes the Water Generator subsystem of the Master Design Simulator. This subsystem simulates the flow of water through a typical watershed-reservoir combination to predict mine drainage quantities in underground workings. The model is a integrated one which handles both the unsaturated and the saturated flow domains as a unified system. The solution of the model is achieved by numerical tech¬niques of finite difference method coupled with finite elements analysis. The Water Generator can be operated either as a free standing model or in connection with the Geology and Reserves subsystem as a part of the Master Design Simulator. A case study is included illustrating the application of the model to actual data. The appendices of the report constitute a user's manual for the program, and include a program listing.

Jan 1, 1975

By J. F. T. Agapito

OCI Wyoming mines two flat-lying trona seams that are 3- to 3.5-m- (10- to 11.5-ft-) thick, about10 m (33 ft) apart and 250-m- (820-ft-) deep at its Big Island Mine in Wyoming. Continuous miners and a yielding-pillar system have contributed to improvements in resource recovery and productivity. The use of yield pillars minimizes the stresses transmitted from the upper to the lower seam. However, yielding must not impact the good, long-term stability needed to prevent subsidence for a large portion of the mine beneath the Green River channel.

Jan 1, 2000

By Alicia O'Reardon

DIFFIDENTLY, because don'ts are rarely greeted with cheers; humbly, because I, myself, have never lined up with the irreproachables, I venture on the subject of manners for the mining camp matron. Mining camps can be divided roughly into two types-the large, opulent settlement that blooms like the rose about a strong mine in full operation; and the puny group of adobe huts, or calamina shacks, or even canvas tents flung down in the wilderness to shelter the gay pioneers of a shining prospect or the shattered survivors of a lost hope. Of the first, I know nothing; but in the second, I have spent some of my best years, and from its curious code of morals and manners, its comic hates and its unreasoning loves, its high impatience and its engulfing kindness, I have charted the narrow .and pitted path which must be trod by the woman who would success¬fully live therein.

Jan 1, 1936

Organization Place Date 1917 American Institute of Architects Philadelphia,.,; Pa. Dec. 26-29 American Society of Mechanical Engineers New York City. Dec. 26-29 American Mining Congress State Chapter Phoenix, Ariz. Dec. 26-29

Jan 11, 1917

By Ebrahim Farrokh

Ghomroud water conveyance tunnel project is under construction using shield Tunnel Boring Machines (TBM) for a total length in excess of 50 km. Phase 1 of the project included 36 km of tunnel divided into four lots (1, 2, 3, and 4) of nine km each. Lots 3 and 4 of this tunnel for a total length of 18 km were combined into one award and have been constructed using a double shield (DS) TBM or one path system. Extreme ground convergence in some sections of the tunnel has stalled TBM performance in early reaches, due to face collapse and shield jammings. This paper presents the latest update on the tunnel progress and impact of ground convergence on machine performance based on the information obtained from field observations. Also, the method and results of tunnel convergence measurements were studied in conjunction with geological parameters and an attempt was made to correlate TBM operational parameters and ground convergence. The result of the analysis indicates a good correlation between machine?s operational parameter and tunnel convergence and can be used as an indicator of the potential for high rates of convergence. An early warning on ground convergence is essential for taking precautionary measures to avoid TBM jamming and related long delays and costs.