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By K. G. Kebkal, R. Bannasch

"Because the operation of tethered underwater vehicles in the deep ocean or under drifting ice areas is very complicated or impossible, the application of autonomous underwater vehicles (AUV) is preferred or even the only possible solution. However, this implies the possibility of a direct and real-time control over all AUV functions, which is only achievable with the availability of accurate positioning/navigation and a high-speed communication link. This paper presents a flexible bottom- or surface-based solution enabling high positioning accuracy of underwater objects (harvester, AUVs, bottom nodes); specifically, a multifunctional system that combines Ultra Short Baseline (USBL) transceivers and Long BaseLine (LBL) stations deployed at a large depth. Moreover, each baseline transponder is equipped with a high-speed communication device to provide the means for real-time AUV control based on the information about its current position, e.g. navigate it with direct commands and operating its actuators and other mechanisms. Moreover a communication link with a high data rate can provide valuable visual information from the operation area.Depending on how many nodes the LBL grid comprise has, target transponder positions can be estimated with an accuracy of several to tens of centimetres. The purpose of the paper is to present the experiments with all key elements of the multifunctional Hydro-Acoustic USBL-aided LBL Positioning and Communication System."

Sep 1, 2014

By R. V. Ramani, K. Bode

"IntroductionIn part 1 of this paper, the results of the experimental work in a wind tunnel under controlled conditions were presented. To understand the spatial and temporal behaviour of airborne dust under mine conditions, experiments were performed in the Lake Lynn Experimental Mine of the US Bureau of Mines. The mine airway experiments were designed to study the variations of ambient concentrations along the length of an airway, and the deposition rates and deposition velocities in an airway cross section. Other objectives of the study were to investigate the spatial and temporal behaviour of airborne dust with regard to air velocity and particle density, the size distribution of the airborne dust cloud as it travels in the airway, and the size distribution of the dust particles deposited along the airway. Other objectives of the study were to compare wind tunnel results with In-Mine results, whenever appropriate.Experimental ProcedureLocationA complete description of the Lake Lynn Laboratory Mine of the US Bureau of Mines (USBM) can be found in the US Bureau of Mines Information Circular 8911 (Mattes et al., 1983). This mine provides excellent facilities for dust experiments. The airway dimensions are similar to those of a coal mine airway. The mine has a drift (D Drift, see Figure 1) that extends almost 500 meters without interconnecting airways, stoppings, or bends. The D drift measures approximately 6m in width and 2,25m in height.The Lake Lynn Laboratory Mine· is ventilated by a variable speed, 75 kW (100 hp), 28,3 m3/s (60 000 cfm) blower fan installed on the top of the ventilation shaft. Air velocities of 1, 1,3 and 1,8 m/s, respectively, could be obtained in the D Drift. However, the temperature changes at the surface can cause small variations in air quantities and velocities underground. The low background dust level in the mine reduces the problem of sample contamination from other sources of dust. Extended periods of uninterrupted data collection can also be scheduled. Mine airway parameters which are important for the analysis include the dimensions of the airway and the ventilation data such as the air velocity, and the pressure loss in the drift. All these data were acquired during altimeter surveys which were conducted prior to each of the experiments."

Dec 1, 1995

By M. K. Mohanty

Due to inefficiencies of the flotation process, significant effort has been recently provided to develop gravity separators for treating ultrafine particles. As a result, several enhanced gravity concentrators have been developed and commercialized. The Altair Centrifugal Jig is an enhanced gravity separator that provides relatively efficient separations on +25 µm size fractions. An experimental program conducted on -600 µm coal found that the Altair Jig reduced the ash content of the 600 x 44 µm from about 30% to 10% with an 86% combustible recovery value. The pulse water pressure, feed volumetric rate and ragging volume were found to be the key operating parameters affecting the separation performances obtained from the process. An extremely low density cut point of 1.54 and an Ep value of 0.08 were indicative of the high process efficiency values achievable by the Altair jig.

Jan 1, 1998

By Lulie H. Crump

Salient information on reserves, production, and consumption of fuels and energy by State are summarized in this Bureau of Mines publication. The data are broken down by fossil fuels (coal, petroleum, and natural gas) and hydropower and nuclear for the major consuming sectors: Household-Commercial, Industrial, Transportation, Electric Power and Miscellaneous. In addition, total energy consumption in the Nation in 1972 is compared with consumption in 1971 and 1973 (preliminary data).

Jan 1, 1974

By Alton B. Cook, G. B. Shea

"INTRODUCTION In February 1945, Captain (now Commodore) W. G. Greeman, U. S. N., Director, Naval Petroleum and Oil 3hale Reserves, requested the Bureau of Mines to assist the Navy in its wartime development of Naval Petroleum Reserve No. 1, Elk Hills field, Calif., to assure adequate supplies of petroleum products in the Pacific theatre. Unit Operation 4/,engineers desired pressure volume-temperature and viscosity data on the reservoir oil in the shallow oil zone to augment data previously obtained for the purpose of calculating reservoir performance and oil reserves. Accordingly, arrangements were approved by the Operating Committee far, the Bureau of Mines to proceed with a program of field sampling and laboratory determinations designed to obtain the desired information.To carry out the assignment, the Bureau transferred the necessary person¬nel, subsurface pressure, temperature, and sampling instruments, and laboratory equipment for analyzing subsurface oil samples from the Petroleum Experiment Station, Bartlesville, Okla., and the San Francisco, Calif., office and set up a temporary field headquarters in the Elk Hills. The program of work as out-lined by Unit Operation required the 6 months period March-August 1945 to complete during which time individual reports comprising data on pressure-volume-temperature relationships and reservoir oil viscosities as determined on subsurface oil samples and recombined oil and gas samples for 5 selected wells were submitted to Unit Operation.This report is a summary compilation of the data contained in the original reports supplemented by correlations of some of the physical properties of the reservoir oil with the A.P.I. gravities of the produced oil. The report also includes material-balance calculations relative to one of the oil horizons in the shallow zone. The Bureau of Mines believes that publication of the results of these analyses is a worthwhile contribution to the petroleum literature and of particular interest to the California industry."

Apr 1, 1947

By R. Krentz, P. D. Cordingley

The nickel-cobalt sulphides produced from limonitic laterite ores by Moa Nickel S.A. in Cuba are refined at the Corefco nickel-cobalt refinery in Canada. Major changes to the refining process were required when the Moa sulphide feed, with its unusually high cobalt content, was introduced in the early 1990's. In the period 1994 to 2005 the production capacity of the refinery has increased dramatically to match increases at Moa, and significant process improvements incorporated. The process flowsheet consists of the original ammonia leach process, optimized for cobalt chemistry and overall leaching capacity. Extraction of metal values is followed by the unique nickel-cobalt separation technology, in which most of the cobalt is separated from the ammoniacal nickel sulphate leach solution by precipitation as a nickel-cobalt hexammine salt. This salt is refined from a Co:Ni ratio of 1:1 to over 10,000:1 by selectively leaching nickel, redissolution and recrystallization in ammonium sulphate solution. Nickel and cobalt are recovered using the well-known Sherritt hydrogen reduction technology. This paper reviews the chemistry described above, examines some of the changes in operating conditions made over the years and highlights some of the recent physical changes made to the refinery.

Jan 1, 2005

By R. V. Higgins, A. J. Leighton

A computer program has been devised to calculate the reservoir performance of water floods of complicated well - spacing patterns . The method and program have been tested by calculating the waterflood performance of fivespot patterns using oils of different viscosities and the performance calculations agreed closely with laboratory results . The program on a high - speed digital computer will process the performance prediction in about 1 minute , which is very rapid for a prediction using so much fluid mechanics and nonlinear geometry . The program has been presented in such a way that one may use it as given and save the time required to write and " debug " one of his own . gram processes a complex reservoir analysis , many of the complicated steps are explained in detail , both for the fluid mechanics and the directions for the computer . The subtle features that originally delayed the application of the program to unusual combinations of permeability and viscosity relationships are incorporated and explained

Jan 1, 1963

By Joseph J. Wallace

The 1952 Annual Report of the West Virginia Department of Mines lists seven beds that are being mined in Mingo County, of which the Cedar Grove is the most important. The Cedar Grove, Alma, and Coalburg contain the largest remaining known reserves. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 tons per acre-foot of coal in place, are estimated at 3,007 million short tons as of January 1, 1953. Of this total, 2,396 million short tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics are too meager for making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1954

By Harold J. Barnett

In January 1948 , the Secretary of the Interior directed that a study be made of energy resources and requirements that would provide a basis for continuing appraisal of the adequacy of the Department's programs in the energy field . That this instruction was timely has been demonstrated by the increasing interest being evidenced by Congress , industry , labor , and the public in the future of the energy segment of our national economy . Several studies of individual energy sectors have appeared . Various legislative proposals have been made in Congress for obtaining more information on this subject . Substantial interest in energy projections is not , of course , a recent innovation . Energy availability and consumption are strategic factors in peacetime prosperity and growth and in our national defense as well . The past generation's literature of earnest public discussion and of legislative consideration of matters involving energy projections is very extensive . This is an exploratory study produced in the Program Staff of the Office of the Secretary of the Interior in the first half of 1949 and revised recently to take account of certain of the preliminary energy data from the 1947 Census of Manufactures and critical comments . It is offered at this time solely as a technical contribution in economic research technique . As the Bureau of Mines has recently undertaken to revise this preliminary study , critical and other comments are invited .

Oct 1, 1950

By M. Didyk

The final objective of a mine ventilation project is to find a way of supplying the working faces with the necessary quantity of air to dilute all the possible air contaminants to safe limits and to maintain the temperature, humidity and oxygen content within desirable limits. To accomplish the aforesaid, decisions have to be made at early stages of planning and design of a mining operation. That is, ventilation and mine planning are closely related and interdependent, and experience has proved that improvisation as related to mine environment is rarely optimal in ventilation engineering. Mine management should be concerned with two general aspects of ventilation problems. The first is related to the statuatory requirements which are usually the minimum standards that have to be maintained. During the last two decades, mining laws have become increasingly stringent and management of operating mines had to face the effects of these externalities. In some cases these required either a production rate reduction or additional mine development. The second aspect that management should not overlook is the technical and economical importance of mine ventilation on the overall mining cost. In coal mining it is necessary to move, on an average, five tons of air through the mine for each ton of coal produced. The power cost incurred is perhaps the single most important direct cost assigned to ventilation but it is not the only one. Other costs that should be considered include the supervisory labor cost, fan depreciation and maintenance, doors, stoppings and regulators construction cost and maintenance, the additional mine airways development and maintenance because of ventilation requirements. That is,

Jan 1, 1977

By D. Hodouin

Jan 1, 1978

By George K. Burke

Underpinning of a structure has been traditionally expensive, time consuming, and, in many cases, caused as much settlement to the existing structure as it was trying to prevent. As underpinning is normally one of the initial tasks and on the critical path on a construction project, there is immense pressure on the subcontractor to speed up his operation so the new structure can proceed; this can cause an adversarial relationship to develop between the owner, engineers, general contractor and subcontractor. Since its introduction to the North American market in the late 1980's, Jet Grouting has not solved all these problems, but where utilized, has shown economical benefits, a faster and safer installation, and a minimal movement of the structures being underpinned. A history of the development of jet grouting is presented; a comparison of this technique versus other grouting methods, a description of the jet grouting system with emphasis on the triple rod systems; case histories of jet grouting used for underpinning and conclusions and references are included to follow the program's themes of: - Recognizing Solutions to Today's Problems - Defining Tomorrows Challenges - Putting America on a Solid Foundation

Jan 1, 1991

By R. J. Kuczynski

The U.S. Bureau of Mines Reno Research Center investigated, developed, and patented a high-temperature cyanide leaching process for recovering platinum-group metals (PGM) from automobile catalysts. A batch pilot plant was constructed at the center and operated to demonstrate this technology to industry. Approximately 1,600 kg of used pellet, monolith, and metal support catalysts containing 1,700 g (54 tr oz) of PGM was processed. Forty-five-kilogram batches of used catalysts were leached with sodium cyanide solution at 160°C for 1 h in a countercurrent processing sequence. This selectively dissolved the PGM. Average extractions from the used pellet catalyst were 96 pet Pt, 95 pct Pd, and 73 pct Rh. Average extractions from the used monolith catalyst were 84 pct Pt, 81 pct Pd, and 66 pet Rh. Heating the pregnant leach solutions to 275°C for 4 h destroyed the PGM-cyanide complexes, causing over 99.7 pct of the PGM to precipitate from solution. The PGM precipitate was predominantly a metallic powder concentrate, typically analyzing greater than 50 pct PGM. Heating destroyed the cyanide to less than 0.2 mg/L free and total cyanide. Both the pellet and monolith residues were evaluated for disposal using the toxicity characteristic leaching procedure developed by the U.S. Environmental Protection Agency.

Jan 1, 2010

Folklore suggests that oxidation is detrimental to sulfide mineral flotation, and in many instances is the reason given for values reporting in the tailing. However, while a considerable body of work examining galena oxidation is available in the literature there are very few studies that investigate the consequences of galena oxidation on its subsequent flotation in base metal sulfide ores. This work clearly demonstrates that pyrite forms a galvanic couple with galena, due to the large difference in their rest potentials, and results in accelerated oxidation of galena, particularly as the pyrite content of the ore is increased. The most obvious effect of the galvanic oxidation of galena by pyrite is the release into the system of galena oxidation products, providing an ample supply of lead ions available to activate gangue minerals, most notably of which in lead/zinc ores is sphalerite. The inadvertent activation of sphalerite by lead ions inevitably leads to the recovery of liberated sphalerite into the lead concentrate, and as a consequence a reduction in the lead concentrate grade. That is, a loss of selectivity for galena against sphalerite. If galena oxidation is excessive not only is there a considerable loss in lead concentrate grade, but also a marked decreased in lead recovery as the flotation rates of the gangue minerals increase, until they rival that of galena.

Jan 1, 2005

By A. J. DeArdo

Linepipe steels have come a long way in the past forty years. In fact, modern, high strength steels for large diameter linepipe applications represent one of the seminal accomplishments in metallurgy of the past half-century. The synergy of advanced steelmaking, alloy design including microalloying, hot rolling, and interrupted accelerated cooling has led to the marvelous steels being used today. The drive for higher performance pipelines has been motivated by the energy sector of our global economy who wanted both higher throughput capacity, i.e., larger diameters and higher pressures, and lower material cost, i.e., relatively thinner gauge wall thicknesses. These requirements led to new steels with higher strengths, better toughness and improved weldability. The goal of this paper is to trace the evolution of linepipe steels from the X60 grades of the small diameter pipelines of the 1960s to the (X80 - X120) grades used in the large diameter pipelines of today. The metallurgical triumphs permitting this success story, e.g., clean steel practices, controlled rolling, microalloying with Nb, and using IAC to obtain low temperature transformation products, will be highlighted and discussed.

Jan 1, 2005

By S. Kodama

Starting on a small scale, the equipment for processing synthesis gas to form liquid hydrocarbons was expanded to handle 100 m) 3/hr. This reactor was successfully designed and constructed, and a basis for future design methods was established. Because, however, this work was carried out on an empirical basis, it is felt that a more thorough theoretical study should be made in an effort to increase the efficiency of the process, particularly in the development of a simpler converter.

Jan 1, 1951

By W. C. Phalen

During the search for deposits of soluble potash salts in the United States, carried on by the United States Geological Survey, much infor- mation was collected on the salt resources and industry of the United States. The more important features of the information thus gath- ered, compiled, and digested may be classified under five headings, as follows: 1. Geology of the salt deposits of the United States. 2. Theories relating to the origin and formation of salt deposits. 3. Chemical composition of saline materials in the United States, principally rock salt and natural and artificial brines. 4. Statistics of salt production in the United States. 5. Technology of salt production. The first four items are not discussed in this report, but their treatment will comprise a separate report published by the Geologi- cal Survey, which will supplement this report, relating to salt- making processes, and will describe comprehensively the salt resources of the United States. Persons desiring a copy of that report should apply to the Director of the United States Geological Survey, Wash- ington, D. C. In addition to the discussion of processes, this report gives a brief description of the more important sources of salt in the United States. This description has been abstracted from the much length- ier description contained in the report to be published by the Geo- logical Survey.

Jan 1, 1917

By William R. Hardwick

Present information indicates that a copper deposit can be safely fractured with a nuclear explosive and the copper successfully recovered by the in-situ leaching method. The process is not yet at the stage where it can be presented t ) the mining industry as a technique proven in all its aspects, but it is a method with high success potential. Unknown factors must be evaluated by a full-scale test before the economics or the extent of the use of the method by the mining industry can be predicted. Preliminary calculations indicate that the cost of fracturing a copper deposit nuclear explosives may range from l.8 to 55.2 cents per ton or in some case: less than a cent per pound of recoverable copper. Copper may be recovered at less cost than by conventional methods. Deposits with 4 pounds of recoverable copper may be economic and production from a deposit may begin in less than half the time required for conventional methods.

Jan 1, 1967

By W. L. Hunter

This report describes results of beneficiation and smelting studies conducted by the Federal Bureau of Mines on chromite samples from the Emma Belle and Seiad Creek prospects in the Seiad Creek area, northern California. Samples were chosen from this area because the ore is typical of disseminated types that represent a sizable domestic reserve. The two samples were similar in composition, and both responded in like manner to gravity beneficiation. As the ore was banded, considerable coarse gangue was rejected in laboratory sink-float from a minus-3/4-inch, plus-6-mesh fraction without excessive chromium loss at a medium density of 3.32. An average of 85.6 percent of the chromium was recovered in the sink product, which analyzed 35 percent chromic oxide (Cr203). Tabling yielded concentrates containing 49 percent or more Cr203; however, recoveries, ranged from only 33 to 45 percent. A combination of tabling and electrostatic separation of the table middlings showed that the chromium recovery could be increased to about 73 percent; the composite concentrate averaged 53 percent Cr203.

Jan 1, 1960

By Clark Harrison

It is not uncommon for overall quality of coal from a mine to deteriorate as the mine is developed or for an improved-quality coal specification to be imposed during the life of the mine. Either of these conditions typically results in management pressuring mine personnel to take greater care in delineating the seam from top and bottom rock. When mining and seam conditions require a portion of the seam to be removed to ensure sufficient rock is removed to meet the quality specification, physical-coal cleaning may become economically competitive with in-pit seam grooming. The additional cost of coal cleaning may, in some cases, be justified by permitting higher recovery of the coal seam than is possible when cleaning the seam with excavators in the pit. This paper compares projected coal cleaning results with present in-pit grooming techniques and reports the economic results.

Jan 1, 1987