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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 Edmond Chin

The land mass of the Asia and Pacific region comprises 11 million square miles or about 15% of the total Earth's land area. The bulk of the region is contained on the Asian continental land mass. Australia, the world's largest island or the world's smallest continent, alone is almost as large as the continental United States. The islands of New Zealand, New Guinea, Borneo, Sumatra, and Honshu are among the largest in the world. Collectively, they constitute a land area of 1.1 million square miles or an area about one-fourth the size of the United States. The countries in the Asia and Pacific region represent some of the most vibrant economies in the world. Japan is undisputed as one of the world's leaders in manufacturing and commerce. Hong Kong and Singapore are significant both as entrepôt and banking centers. The economies of Australia, the Republic of Korea, and Taiwan compare favorably to the level of the industrialized countries in western Europe. Indonesia, Malaysia, the Philippines, and Thailand have maintained strong economic growth during the past two decades. All these countries in the Asia and Pacific region collectively constitute a significant bloc as to raw materials production and consumption, as to manufacturing, and as to world trade.

Jan 1, 1992

The revised estimate of coal production in January 1977, is 39 million tons -- down 12 mi 11 ion tons compared with production in January of last year, largely as a consequence of the snow storms and cold. The major coal-hauling railroads operating in Eastern and Midwestern States reported to the Bureau of Mines that they loaded approximately the same number of cars for the week ended February 5, as in the preceding week. The Bureau of Mines estimates that U.S. coal production for the week ending February 5, 1977, was approximately 8.5 million tons, or nearly 3.5 million tons less than production for the corresponding week in 1976. Coal production from January 1 - February 5, 1977, was approximately 47.8 mi 11 ion tons compared with production of 63.5 million tons for the corresponding period in 1976. As of the first week in February, river and truck shipments of coal in the Eastern U.S. were about one-half of the normal traffic. Despite the freezing weather and ice and snow conditions of rivers and highways and reduced rail shipments, there was reportedly little or no shortage in coal supply to consumers. Inventories at electric utility plants and steel company coke plants at the beginning of the severe weather were sufficient in most cases for at least 30 days" operations. There have been no reports of coal shortages at other industrial plants.

Jan 1, 1977

Demand for primary aluminum ingot increased during February, and several producers temporarily suspended new bookings for ingot. Alcoa announced that it would restart a potline at its Warrick, IN aluminum smelter by April 1, 1979, increasing the operations of that plant to its full capacity of 290,000 tons per year. At the end of February, it was reported that Alcoa would reactivate two of the seven units at its idle Point Comfort, TX smelter in May 1979, increasing the company's annual capacity by about 60,000 tons.

Jan 1, 1979

By Joan Weinberg

The economy continued to expand during the third quarter, as real GNP rose at a seasonally adjusted annual rate of 3.8%, up from 2.5% in the second quarter (table 1). Continued job gains (see below), higher incomes, and an increase in installment debt, resulted in a nearly 20% increase in consumer spending on durable goods. Consumer expenditure on nondurables fell slightly, while spending on services continued at a moderate pace. Nonresidential fixed investment climbed nearly 24%, as producers purchased more durable equipment. Residential fixed investment was adversely affected by rising interest rates, which slowed new home construction from January to August, 1987 to a rate 11.2% below a comparable period in 1986. Net exports of goods and services deteriorated slightly, after three consecutive quarters of improvement. The volume of net exports has risen 15% for the year, contributing to economic and employment growth, but large price increases on imports have slowed the improvement in the nominal trade balance. Although U.S. goods have declined in price relative to foreign goods because of the devaluation of the dollar, faster growth in exports is hampered by austerity programs in developing countries, and emphasis in Germany and Japan on curtailing inflation and fiscal deficits.

Jan 1, 1987

[Determine how subsidence resulting from underground coal mining affects surface structures, and evaluate the usefulness s of the tiltmeter for monitoring foundation movement. Approach The Bureau of Mines is studying foundation response to mine subsidence in order to determine how subsidence-induced ground movements affect foundations in place directly above the mint. These investigations are essential if economic mitigation and repair techniques are to be made. In addition, commercially available tiltmeter are being evaluated (or use as a cost-effective monitoring technique. To study foundation response and to evaluate the tiltmeter system, full-scale model foundations were constructed, instrumented, and monitored for three years. Vertical and horizontal displacements, tilt magnitudes and directions, and observed damages were recorded. Displacements were compared with measured lilt to determine if the tiltmeter was tracking foundation response to subsidence, The Bureau developed a computer software package to aid in the reduction and analysis of the tiltmeter data.]

Jan 1, 1988

By Michael A. Trevits

During the time period from 1990-2007, there were 1601 reportable fires that occurred in the U.S. mining industry (an average of 89 fires per year). The leading causes of U.S. mine fires include flame cutting and welding operations, frictional heating and ignitions, electrical shorts, mobile equipment malfunctions, and spontaneous combustion. The National Institute for Occupational Safety and Health (NIOSH) is conducting a program of research addressing metal/nonmetal and coal mine fire prevention, detection, management and suppression. In the metal/nonmetal area, work was focused on technology transfer and training, and research to reduce the number of mobile equipment fires and their hazards. In the coal arena, research is underway to determine the root cause of cutting and welding-related fires and to evaluate the effects of ventilation schemes relative to the spontaneous combustion risk in longwall mines. Relative to fire management, research is ongoing on remote mine seal installation and remote mine fire suppression technologies. Finally, research is continuing to develop comprehensive and usable smoke management techniques and to develop mine fire growth models, propagation, and suppression. This paper presents a summary of some of the mine fire research and provides an overview of the next phase of the NIOSH mine fire research program.

Jan 1, 2010

By C. K. Eilerts

Knowledge of the phase relations of the fluids that exist in the porous spaces of rocks constituting natural petroleum reservoirs and of the behavior of these fluids under various field conditions of operation is essential to the conservation of petroleum and natural gas and to their efficient recovery. The problem of determining whether these fluids are in the liquid or gaseous state and of recognizing the transitions that may take place as the material in the reservoir is subjected to different conditions of pressure and temperature confronts many producers today, especially in certain fields. The subject has grown rapidly in importance since the discovery of and production from deeper reservoirs that have correspondingly higher pressures and temperatures as compared with shallower

Jan 1, 1938

By A. L. Podia

The purpose of this research was to develop a system capable of detecting changes in the structure of rocks, leading to failure of mine roofs, and/or excavations. A prototype system was developed, field tested and delivered to the United States Bureau of Mines for further evaluation and research. This system is based on the analysis of acoustic signals generated on the surface of the roof by an impact device and which are reflected or backscattered by flaws and discontinuities in the rock. The specially designed impact source is capable of generating high frequency acoustic signals with excellent repeatability. The system can also be used in conjunction with conventional acoustic pulse transducers. The received signal is digitized and the data transferred to a minicomputer for processing and display. This capability allows the immediate determination of wave velocity and/or distance to a reflecting interface. Various data processing techniques such as averaging, differentiating, and comparing of different signals can be selected by entering the appropriate commands on the keyboard. Being a programmable system it is possible to implement more advanced signal processing techniques. All results as well as the signal are displayed on a CRT. Furthermore, a permanent record of the data can be generated on paper tape, which can be reentered and processed at a later date. A communications interface allows transmission of the sampled signal to a large scale re-mote computer. The system was tested extensively in the laboratory, and field tested at the York Canyon Coal Mine. These tests proved the feasibility of operation in the mining environment. Results indicate that further investigation and development will have to be undertaken to fully develop the potential of this system in satisfying the goals of this research.

Jan 1, 1973

By R. G. Gürtunca

The future of the United States (US) mining industry will be affected greatly by recent coal mining disasters. These have resulted in new legislation which will have an impact on mining economic costs as well safety and health of miners. This paper discusses the changes that new legislation and regulations are making to the industry and current research that is producing technologies to make mining safer and will likely impact the future of mining.

Jan 1, 2009

By Hugo E. Camargo

Noise Induced Hearing Loss (NIHL) is the most common occupational disease in the U.S. with devastating consequences particularly in the mining industry. A study conducted by the National Institute for Occupational Safety and Health (NIOSH) revealed that 90% of coal miners have hearing impairment by age 50, compared to only 10% of those not exposed to occupational noise. According to the Mine Safety and Health Administration (MSHA), Continuous Mining Machine (CM) operators account for 30% of workers exposed to noise doses exceeding the Permissible Exposure Level (PEL). This number becomes more dramatic considering that 49% of the total national underground coal production is extracted using these machines. In this context, NIOSH is conducting research to identify and control dominant noise sources in CMs. Previous noise source identification was performed using a Brüel &Kjær (B&K) 1.92-m diameter, 42-microphone phased array. These measurements revealed that the impacts from the conveyor chain onto the tail roller, and the impacts from the conveyor chain onto the upper deck are the dominant noise sources at the tail-section of the CM. The objectives of the work presented in this paper were: 1) To rank the noise radiated by the different sections of the conveyor, and 2) to determine the effect of a urethane-coated tail roller on the noise radiated by the tail-section. This test was conducted using an Acoustical and Vibrations Engineering Consultants (AVEC) 3.5-m diameter, 121-microphone phased array. The results from this new test show that a urethane-coated tail roller yields reductions in the tail-section of 2 to 8 dB in Sound Pressure Level in the frequency range of 1 kHz to 5 kHz. However, integration of the acoustic maps shows that the front-section and mid-section of the conveyor also contain dominant noise sources. Therefore, a urethane-coated tail roller in combination with a chain with urethane-coated flights that reduces the noise sources in the front and mid sections of the conveyor is required toyield a significant noise reduction on the CM operator?s overall exposure. These results show the applicability of phased array technology for low frequency noise source identification.

Jan 1, 2008

By James R. Wait

The present final report constitutes the total productivity of a series of contracts from the U.S. Bureau of Mines and the Institute for Telecommunication Sciences over the period 1971-1979. The emphasis on the research has been analytical. In this "executive summary" we give a succinct description of each phase of the investigation. In the first phase of the investigation that was stimulated by the National Academy of Engineering, we concentrated on the analytical studies of techniques relevant to mine rescue. Several specific procedures for locating a buried source were analyzed. In the next, but overlapping phase of the investigation, we dealt with the fundemental character of how electromagnetic waves propagate in mine tunnels. At the outset we allowed for the finite conductivity of the tunnel walls and the presence of axial conductors such as cables, pipes, and tracks. The third phase of the investigation was devoted to the analyses of various specific geophysical engineering problems. The related fourth phase dealt with the general subject of non-destructive testing of wire ropes such as used for mine hoists.

Jan 1, 1980

By J. B. Gayle

In a modern blast furnace, production depends, to a large extent, on the rate at which the furnace gases can be forced through the charge. Since these gases must make their way through the voids between particles of coke, ore, and limestone, the size and size distribution of the stock-column materials are of considerable importance. Also, because the coke pieces support the weight of the overburden and provide the majority of the voids through which the gases pass, their ability to withstand the shattering and abrading forces to which they are subjected should be related to the maximum obtainable production for any particular furnace. Although the wide acceptance of this point of view is indicated by the ever-increasing demand for stronger and more uniform blast-furnace cokes, economic considerations demand that a quantitative evaluation of the relation between coke quality and blast-furnace performance be made available to the industry at the earliest possible date. The following studies of size-distribution patterns and breakage processes were, therefore, conducted as a part of a preliminary investigation intended as a basis for future studies of the relation between coke quality and blast-furnace performance. The major findings may be summarized as follows: 1. New evidence for the presence of two independent distributions of sizes in run-of-oven cokes has been obtained, and a method for characterizing and estimating the relative importance of the individual distributions has been demonstrated. This method has also been used to study the different types of degradation taking place during the tumbler test.

Jan 1, 1954

The U.S. economy continued to expand during 1986, although at the slowest pace since 1982 when the current business expansion began. Real gross national product (GNP) grew about 2.6%, slightly below 1985 growth but significantly below that of 1984. The continuing expansion was fueled pre-dominantly by rising personal consumption expenditures as well as growing Government purchases of goods and services. Fixed investment, although positive, failed to grow at the rate of the overall economy. The trade deficit, which increased more than 30% over the record 1985 level, continued to depress economic growth despite significant declines in the price of petroleum and the value of the dollar. On a more positive note, domestic employment continued to grow--increasing over 2 million from the 1985 level--and inflation and interest rates declined. The unemployment rate dropped slightly to 7.0%. Of direct importance to the mineral-producing industries, expenditures for consumer and producer durables as well as investment in residential construction each grew faster than the overall economy, but investment in nonresidential structures fell more than 10% from the 1985 level. The level of real capital spending declined about 3% in 1986, following strong gains in 1985 and in 1984. Capital expenditures for new plant and equipment bottomed out in the second quarter and expanded in the third and fourth quarters. The decline in the first half of the year was partially attributed to uncertainty arising from the then-proposed tax bill. Also, there was little impetus for corporations to invest in new capacity since factories were operating at less than 80% of capacity during most of the year, in part because of continued competition from imports.

Jan 1, 1986

By Almon F. Robertson

This report is one of a series based upon investigations made and being made within the Missouri River Basin in Montana by engineers of the Bureau of Mines , Albany Branch , Mining Division . These investigations are being made primarily to provide preliminary information to the Department of Interior agencies and to others concerned with planning the proposed Federal power developments within the Missouri River Basin. This report has been designed to permit public distribution of the factual data obtained . Virtually all known metallic -mineral occurrences and some nonmetallic mineral deposits within Fergus County were investigated in 1948. The investigations cannot be considered complete , however , because some long inactive mines or prospects may have been missed . Most of the old mine and prospect openings now are caved ; many are completely inaccessible . Many of the claims located years ago have been abandoned ; others have been relocated under different names and ownerships . Because of such conditions , much of the information regarding their development and operation necessarily has been obtained from available Federal and State publications , supplemented by information provided by owners and local residents .

Jan 1, 1950

By J. W. Allen

This report reviews the work performed on Task M of Bu-Mines Contract H0220073 to develop an engineering model of a surface and subsurface communications system for normal mine operations and for post disaster rescue operations. The system concept provides for one-way transmission of digital information between a number of identifiable subsurface terminals or subcenters and a single surface station. It also provides 2-way voice communications between the subcenters and the surface station. The basic communications link is electromagnetic signaling through-the-earth, but the system is also capable of using mine phone lines as an alternate link. Engineering models of three subcenters and one surface terminal (see Figure 1-1) have been fabricated in order to demonstrate the system's performance. The system concept, however, permits up to 20 subcenters to be incorporated if desired. Additional subcenters are also feasible for large mines if they can be deployed in the mine to operate on a noninterfering basis.

Jan 1, 1973

By Byron S. Kutscher

This report summarizes the program to develop and construct an improved light-scattering dust monitor (ILSDM). This improved light-scattering dust monitor, which operates on the forward light scattering principle, provides instantaneous measurements of airborne dust concentrations in units of mg/m. The program was divided into two phases. Phase I involved the design of the ILSDM which was reviewed by the Bureau of Mines. Phase II included the fabrication of a prototype ILSDM based upon the design developed during Phase I. After completion, the ILSDM was delivered and demonstrated at the Bureau of Mines. A description of the final ILSDM design, operating instructions, maintenance instructions and recommendations for additional work are also included in this report.

Jan 1, 1980

By J. D. Davis

THIS-report gives results of in investigation of the carbonizing properties of 18 coals, including 2 from Alaska, 12 from British Columbia, 3 from Washington, and 1 from Utah. Each coal was carbonized in the standard 13-inch Bureau of Mines-American Gas Association (BM-AGA) retort at 900° C. Plastic properties were determined by the Gieseler and Davis methods, and agglutinating and free-swelling properties were determined by standard methods. Expanding properties were measured in the Bureau of Mines sole-heated oven. From the results of the tests on these single coals, three coals from the Crowsnest area in British Columbia, representing Elk River Nos. 4, 9, and 10, were selected for blending with the Utah coal, which was from the Lower Sunnyside bed, Horse Canyon mine, Emery County. Lower Sunnyside also was blended with Wilkeson -Nos. 2 and 3 (Washington) coals, Pocahontas No. 3 from McDowell County, W. Va., and the Oklahoma low-volatile coal used in the blend carbonized at, the Provo, (Utah) coke plant at the time this investigation was started. Most of the blends contained 3 percent hard pitch, which is the proportion used at the Provo plant. The blends were also carbonized in 13-inch BM AGA retorts at 900° C. High-volatile B coal from the No. 3 bed, Evan-Jones mine, Lower Matanuska, Valley, Alaska, yielded poorly fused coke or char. M-bed coal from the Chickaloon mine, Upper Matanuska. Valley, Alaska, ranked as medium-volatile bituminous and coked strongly. It expanded 39.6 percent in the sole-heated oven at a. charge density of 55.5 pounds per cubic foot..

Jan 1, 1952

By Otto L. Schumacher

The Overthrust Belt in portions of Montana, Idaho, Utah, and Wyoming, an area that has contributed generously to the Nation's mineral supply, is one of the few remaining oil and gas frontiers on the North American continent. Determination of the oil and gas potential and development of mineral resources of the area have been affected by a variety of land withdrawals and other restrictions, The purpose of this study is to determine the extent of these withdrawals and restrictions and to discuss the mineral resource potential within the study area. Statistics in this report refer to land status on January 1, 1979. At that time, of the 27.3 million acres of Federal mineral lands within the study area, applications tor Federal oil and gas leases for more than 4,4 million acres (about 16 percent) were pending; the average length of time was 2 years. Federal oil and gas leases covering 8.8 million acres were also on record. Although drilling has occurred on some of these leases, others are subject to restrictions that discourage or prevent development. Some in fact contain stipulations disallowing any development.

Jan 1, 1981

By H. D. Hunt

This paper which describes the milling practice of the Miami Copper Co. is one of a series being prepared by the United States Bureau of Mines. LOCATION The mine, concentrator, and other surface plants of the Miami Copper Co. are located near the town of Miami in the Globe-Miami mining district of Gila County, Ariz.

Jan 1, 1932