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By J. Harrison Daniel

Increasing concerns of industrial hygiene and worker health issues and resulting regulatory actions, coupled with continuing advances in mining systems, are placing new burdens on the industry and Federal Government; particularly, mine ventilation departments. More encompassing worker health programs are required to respond to Federal promulgation of regulations and to keep abreast of techno- logical advances in the mining industry. The relationship between the mining industry and Federal agencies involved in rulemaking is presented, along with the rationale of an Industrial Hygiene Management Plan. This plan or strategy focuses on developing partnerships and collaborative research groups to address the controversial health issues facing not only the mining workforce, but our society.

Jan 1, 1993

By W. Hurst, R. E. Leeser, W. C. Goodson

Three aspects of gas deliverability are presented in this paper. The first treats with the gas deliverability or availability of a normal depletion-type dry gas field. Such encompasses not only the period of stabilized constant rate, but more so, the "tailings" when a fixed abandonment pressure is reached and the rate by necessity must decline. A comprehensive work plot is offered, developed from mathematics herein included, that removes the triai-and-errnr computations that attended such undertakings in the past. The second part treats with the discount factor of the open flow potential constant from what is observed initially in testing a gas well to what is evidenced when stabilization is reached. This prevails in tight formations, such as the Kansas Hugoton field which is offered as the example. The means of establishing this factor are pressure build-up curves which, as sustained by analytical deductions, reproduce this entire period of transient flow under conditions of a constant rate influx. Finally, what is offered in this paper is the deliverability performance of an exceedingly rich gas condensate field producing from a tight formation. The example shown is the Knox Bromide field in Oklahoma, producing from the Bromide formations. The results are ominous, showing early reduction in permeability to gas pow, due to the retrograde condensate forming in the pore space, with the attending early logging-up of these wells. The analytics of lowered permeability are incorporated in the gas deliverability formula along with the PVT data that gives the increased condensate liquid saturation as the gas flows to the well bore. This paper would not be complete without a critique oflered at the end. With the many gas wells now in production and those that have completed their life, there has been no factual information collected by any source as to what constitutes that permeability range where a gas well would be unimpaired in its gas deliverability by the presence of rich condensate content, and the lowered range where such would be harmful. This question confronts all producers. INTRODUCTION Various aspects of gas deliverability are presented in this paper that includes depletion-type reservoirs, deteriora- tion factor of the gas deliverability constant, and the performance of a rich gas condensate reservoir producing from a tight sand. With respect to the presentation of gas deliverability and its tailings for depletion-type gas reservoirs, one notes that this is essentially the information offered by every gas transmission company and producer appearing before the Federal Power Commission for Letters of Conveyance in the dedication of reserves. In the ordinary procedure, as many engage upon this study, trial-and-error calculations are included, particularly as apply to the tailings. For many years one of the writers has employed mathematical analyses to perform this step and avoid the complexities so associated. In the preparation of this paper these analyses have been amplified to include any slope n for the open flow potential relationship for which the tailings can be determined from Fig. 1. With reference to the deterioration or discount factor of the open flow potential constant as such occurs in the gas deliverability formula, this for the most part has been an unexplored subject. Although the issue first appeared in the Kansas Hugoton field, where such was surmised but only recently resolved, this situation of a deterioration of the gas deliverability constant can occur wherever dry gas production from a tight sand is encountered. The first concerted attacks upon this problem were the presentations of Hurst' and Goodson' before the Kansas Corporation Commission to show that transient fluid flow and unsteady-state flow formulas prevailed. This was amplified later before the Federal Power Commission3 to show that this deterioration factor could be identified from pressure build-up curves. This has been reported by McMahon.4 Its importance to the industry merits the review of these essential features in completing the program on the aspects of gas deliverability. Finally, as illustrated here, for a low permeability formation such as the Knox Bromide field where the gas is rich, representing some 165 bbl of condensate per MMcf of effluent gas, the gas deliverability can be of limited extent in the life of the field, leaving substantial amounts of condensate and gas unrecovered. In cases such as this, gas cycling is mandatory. This is particularly revealed by the fluid mechanics introduced here, employing factual field as well as laboratory data, to show this-restriction upon gas deliverability. PRESSURE DEPLETION What will now be offered is the study of gas deliver-

By M. Murphy

The multibillion dollar cost of cleaning up thousands of environmentally contaminated sites across the country created by decades of inadequate disposal of hazardous waste has led to a search for "deep-pocket" sources of cleanup funds. The resul1:: is the emergence of a growing body of law that could have a profound impact on commercial financing transactions and other investment activities when present or past owners of contaminated property are involved.

Jan 1, 1988

By Jerry L. Straalsund, D. Bruce Masson

A dew-point technique was used to determine the thermodynamic activity of zinc at 430°C in a series of e phase Ag-Zn alloys. The composition of the alloys ranged from 72 to 88 at. pct Zn. This range included the composition at which Massalski and King3 found a reversal in the composition variation of the crystallo-graphic c/a ratio, which they attributed to an overlap of the Fermi surface across the (002) faces of the Brillouin zone. The data is presented in a graph in which RT In yz,, where yz, is the activity coefficient of zinc, is shown as a function of atomic percent zinc. This curve has an unmistakable change in slope at the same composition that Massalski and King observed the beginning of the reversal in the c/a ratio. This change in slope of the thermodynamic data is also attributed to a Brillouin zone overlap. Equations are presented to demonstrate that the thermodynamic activity can be related to the density of states of the conduction electrons, and that the observed phenomena are consistent with this model. It is also demonstrated that the contribution of the density of states can be related to the excess stability, a phenomenological parameter recently shown by Darkeen" to be significant in the interpretation of thermodynamic data of metallic phases. The data seem to indicate that zone overlap has caused a spinodal point, and the resulting misci-bility gap, in the phase diagram. THE problem of developing an adequate thermodynamic model of solid solutions has proven to be difficult, and is still only partially solved. The main approach has been to develop a statistical model, such as that of an ideal solution, regular solution, and so forth, to which can be attached corrections for electronic, vibrational, magnetic, ordering, or other contributions. Such corrective terms are usually derived on an ad hoc basis, and it is difficult to predict in advance what their relative importance will be. This problem has been discussed in general terms by Oriani and Alcock,' who have reviewed several thermodynamic models and a few empirical correlations. The measurements described in the present paper were made to demonstrate in a special case the importance of one such corrective term, the contribu- tion of the energy of the conduction electrons of an alloy. It was our premise that the contribution of the energy of the conduction electrons to the thermodynamic activity of the alloy components could be detected; further, that such an effect would be observed at alloy compositions where other phenomena, also ascribed to the energy and density of states of the conduction electrons, are observed. The idea of the importance of the conduction electrons is hardly new. Hume-Rothery and his adherents have developed the well-known theory of alloy phases in which the sequence of phase fields in binary equilibrium diagrams, especially those involving the noble metals with the IIB, IIIB, and IVB subgroups, can be correlated by replacing the composition variable with the ratio of conduction electrons to atoms, e/a. Jones and others have developed a physical explanation for this correlation, in which they consider the solubility limits of phase fields to be restricted by an intersection between the Fermi surface and a Brillouin zone. The general features of the model are also quite well-known—presumably zone intersection causes the density of states to decrease at critical alloy compositions. The attendant increase in energy of conduction electrons in the original crystal structure allows an alternate structure to become more stable as the concentration of polyvalent solute is increased. In spite of the wide acceptance of these ideas on phase stability, there is only indirect* evidence, such as the variations in lattice parameter recorded extensively by Massalskizy3 and others, that Brillouin zone interactions occur. There are few experimental measurements, other than the correlations of the phase sequence, that substantiate the premise that the energy of conduction electrons affects the solubility limits of alloy phases. Much thermodynamic data of alloys has been found to be consistent with the theory; yet there is a lack of detailed data at compositions where zone intersection and overlap are thought to occur. One would expect that the energy of the conduction electrons would make a measurable contribution to the thermodynamic properties of alloys at compositions near zone intersection and overlap if the theory of Hume-Rothery and Jones is correct. This conclusion cannot be avoided, because the phase boundaries are determined by the requirement that the chemical potential of the components be equal in both phases at equilibrium. An electronic effect large enough to alter the stability of a phase should also affect the thermodynamic activity by a measurable amount.

Jan 1, 1969

By Emil O. Frind, David W. Blowes, K. Ulrich Mayer

The multicomponent reactive transport model MIN3P can be used to simulate the evolution of pore water, pore gas, and the mineralogical composition in mine waste environments. The model is formulated for variably-saturated conditions, considers transport of dissolved and gaseous species, and describes geochemical reactions based on a partial equilibrium formulation. Reaction processes included are complexation, oxidation-reduction, ion-exchange, mineral dissolution-precipitation and gas exsolution- dissolution reactions. An example application, describing the generation of acid mine drainage and subsequent reactive transport for a ID-vertical profile in a tailings impoundment near Elliot Lake, Ontario, is provided.

Jan 1, 2000

By Kai Bartram

The successful application of color sorting machines has established sensor-based sorting in the mineral industry in recent years and is considered today as a significant innovation in processing technology. However, we are only at the beginning of (market) introduction. New sensor systems have been developed, which exploit material properties such as electrical conductivity, magnetization, molecular structure, thermal conductivity etc. This opens up new exciting preconcentration and upgrading possibilities for many applications such as nickel, gold, copper and other ores as well as for industrial minerals, diamonds and other gem stones.

May 1, 2009

By Bruce A. Lamberton

In U. S. underground mines concrete work is not widely used. Timber and steel are cheaper, and there are few serious water problems. But in the Union of south Africa men dig deeper, more persistently, and probably more profitably than anywhere else on earth. Some gold mines near Johannesburg are below the 10,000 level and employ as many as 35,000 natives on a single property. Underground substations, pump chambers, and air conditioning plants have capacity to serve small cities. The complexity and extent of underground operations and the heavy subsurface water flows, especially in the new Free State gold fields, require heavy in a Deep concrete installations.

Oct 1, 1956

Provide a means through which members of the mining community can easily and readily access information on human factors/ergonomics as it relates to mining. Approach As part of a research study aimed at reducing human error accidents in mining the Bureau of Mines developed a computerized information retrieval system which provides relevant human factors or ergonomics information on 19 mining-related special interest categories.

Jan 1, 1988

By Lawrence W. Hallanger

Anaheim Bay, located at Seal Beach, California, is the site of the Huntington Harbor development of waterfront homes and marine facilities. The main entrance to Anaheim Bay is a relatively narrow channel connecting the bay with the Pacific Ocean which runs under California State Highway One. During the development of Huntington Harbor the old highway bridge was replaced with a new, higher bridge to allow for boat passage through the channel. At that time only the main span decking of the old bridge was removed, leaving the support pillars and the approach ramps in place (see Figure 1). The narrowness of this channel, plus the increasing boat traffic created a situation in which public demand for the removal of the old bridge became significant. Because the bridge was located within the boundaries of the Seal Beach Naval Weapons Station (see Figure 2) the Navy became involved in the bridge removal. Eventually the task was assigned to the Naval Amphibious Construction Battalion One and work began in early 1974.

Jan 1, 1975

By Rex T. Ellington

The fluidized bed is an effective method for investigating retorting phenomena and possibly a commercial means of retorting oil shale. Both were examined by Sinclair Oil (now part of Atlantic Richfield Co.) in the period 1965-1698. The results of the work show that the presence of an oxidizing environment during retorting results in loss of oil yield which indicates that vapor phase oil burns in preference to combustion of coke on spent shale. Consideration of hardware indicates that there are several possibilities for commercial embodiment. As a companion to shaft-type retorts the fluidized bed could have good potential. Realistic assessment of costs suggests that further development may have to wait commercialization of another process.

Jan 1, 1974

By Houston Kempton, David Atkins

Mining in semi-arid climates can produce environmental impacts that will not begin for hundreds of years, but once started, may continue for thousands of years. Pit lakes may eventually exceed toxicity thresholds as metals are evaporatively concentrated, and slow unsaturated flow through acid-generating waste can eventually load several kg-SO4/m2-yr to underlying water tables. U.S. regulations are poorly equipped to respond to delayed and long-term environmental impacts, delaying permits as operators and regulators grapple with uncertainty. Improved uncertainty analysis, additional long-term mitigation options, and explicit regulatory guidance offer solutions to this dilemma.

Jan 1, 2000

By Masaaki Terashi

The machine for the hybrid method called JACSMAN is ordinarily a dual shaft machine. Each shaft has augers at three different levels and nozzles for jetting at two different levels. The distance between two shafts may be changed according to the particular requirements. Figure 4 shows single shaft and a treated soil column created by the method. The diameter of the auger is 1.0 m. As the jetting nozzles locate at the periphery of the auger, jetting can achieve the additional treated soil column beyond the diameter of the auger. The diameter of the jetting improvement is fixed at 2.3 m.

Feb 10, 2003

By W. G. Davenport

Chapter 13 evaluated the %02 in blast, industrial oxygen and oil requirements for smelting FeSrCuFeS2 concentrates~ This chapter examines high eu grade CU2S-CuFeS2 concentrates the same way.

Jan 1, 2001

By R. W. Raymond

THE death of Privy Councilor Bruno Kerl, on March 25, 1905, terminated a distinguished and useful career. Bruno Kerl was born March 24, 1824, at St. Andreasberg in the Harz, and entered in 1840 the mining school of Clausthal, where he studied for three years, working at the same time in the mines and stamp-mills. After an additional year of practice in the silver-reduction and iron-works of the Upper Harz, he passed his examination as a metallurgical graduate, and studied for a year at Göttingen under WV filer in chemistry, Hausmann in mineralogy, and eminent teachers in other branches. In 1846 he was employed at the Oker works, but very soon left this post, to become a tutor in chemistry, metallurgy, etc., at Clausthal, where he continued to labor until 1867. During this period the Clausthal school became a completely equipped Mining Academy, and Kerl was made in 1862 a full professor. Meanwhile, in addition to the work of instruction, he discharged, simultaneously or successively, the duties of many responsible official positions in the Royal Hanoverian administration of mines and smelting-works, and also published many valuable books and treatises. Among these were professional guide-books to the Upper and Lower Harz, and their characteristic metallurgical processes; a manual of qualitative and quantitative blow-pipe analysis; another of metallurgical assaying ; and, most important of all, a Handbook of Metallurgy in four volumes, the second edition of which was issued in Leipzig, 1861-1865. This book was speedily recognized as the leading authority in its field. In this country, the English translation and revision, by Crookes and Röhrig, published about 1869, had a large circulation. In addition to these literary labors, Prof. Kerl became in

Jul 1, 1905

Edgar Hall, Tenterfield, New South Wales (communication to the Secretary): Mr. Klepetko* asks for information showing at what percentage antimony and arsenic, as impurities, begin to affect injuriously the quality of brass.

Jan 1, 1899

By M. L. McAllister, M. Veiga

The mineral industry has seen many significant changes in the past decade. Increasingly, it has responded to unanticipated pressures and demands with a variety of voluntary initiatives. Yet there is still much to do. Mining now takes place in a different context than was the case in the past. Socio-economic, political and environmental considerations must now be integrated into traditional mining systems. This process of integration needs to involve industry, governments, academics, communities and other stakeholders to design a new approach to mining, one that can be fostered through interdisciplinary links and holistic strategies. This paper considers the meaning of sustainability in the context of the Canadian mining industry and explores the need for a broader vision for the mining industry. The role of technology is then analyzed and related to an initiative recently taken by Canadian universities to develop a national network for interdisciplinary research into sustainable mining, CaSM.

Jan 1, 1999

By J. H. Zimmerman

JET-PIERCING experiments were first conducted over ten years ago underground at the Soudan mine of the Oliver Iron Mining Co. Results were successful enough to encourage further research. The next field tests were made on the Reserve Mining Co. property at Babbitt in 1941. These tests showed that blastholes could be produced in taconite ore by the use of a flame and proper fluxing agents. The war put a stop to the experimental program shortly after these tests. Extensive field tests were resumed at Babbitt in 1946. In these tests nominal 6-in. blastholes were produced at an average rate of 10 ft per hour. Rates as high as 17 ft per hour were obtained for short periods. The experimental equipment used resembles a portable rotary-drill rig mounted on a truck. The standard steel mast has been extended to 46 ft to accommodate a blowpipe capable of producing holes over 30 ft deep. All auxiliary equipment including winch for raising and lowering the blowpipe, drive motor for the rotary table, pumps and tanks for process fluids, electric power plant, and control instruments are mounted on the truck. The jet-piercing process consists of

Jan 1, 1948

Presentation Overview ?? Project Setting ? Project Context ? Challenges ?? Managing Commitments ?? Project Update ?? Maximizing Aboriginal Economic Participation in Resource Development PROJECT SETTING ?? Developed on the traditional lands of the Labrador Inuit, and the Labrador Innu ?? Courts have held that Aboriginal peoples in Canada possess special rights to traditional lands ?? Rights can include requiring resource developers to enter into Impacts and Benefits Agreements ?? Development agreement with Newfoundland and Labrador was required

May 1, 2004

By Roy T. Sorensen

This Bureau of Mines report presents the results of a study to rank technologies for extraction of alumina from bottom ash and coal shale. The available literature on composition and availability of coal waste was reviewed, and papers pertinent to alumina extraction are referenced. Types of coal waste were categorized by method of waste generation, coal content (heating value), location, coal type (ash nomenclature), and alkaline earth content. The differences and similarities among the categories of coal waste are summarized as to factors that my affect aluminum extraction, especially factors concerning chemical composition, current production, storage problems, and accumulated tonnage. Data available on physical characteristics and mineralogy did not correlate well with the individual categories of coal waste, and discussion on these two aspects is limited to the differences between coal ash and coal shale.

Jan 1, 1983

By H. Scott

SINCE Böhler discovered, in 1903, on cooling certain alloy steels, the phenomenon of a new and lower temperature transformation than the usual Ar3_2_1 obtained by increasing the maximum temperature to which the material was heated, much has been published' connecting this phenomenon with a large number of dissimilar steels of high alloy content. From the fact that the transformation divides itself, taking place at two widely separated temperatures, it has been called a "split transformation." The, significant facts established by recent investigators' are: that when the' transformation occurs at the higher temperature Ar', troostite or a decomposition product is formed, and that when the transformation occurs at the lower temperature Ar", the resulting structure is martensite. The terminology Ar' and Ar" adopted here is that of Portevin.3

Jan 2, 1919