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By Oscar Lee, B. W. Gandrud, F. D. DeVaney

"IntroductionFlue dust which results from the smelting of ores containing appreciable quantities of fines is one of the troublesome products of iron blast-furnace practice. Gases issuing from the furnaces at a high velocity carry small particles of coke, ore and flux into dust-collecting chambers. These particles constitute the flue dust. Lasses of iron ore through the production of flue dust vary between wide limits in the different furnaces, and depend on a number of factors, such as size and design of furnace, amount of fines in the ore, the operating conditions and the blast pressure.Blast-furnace operators of the Birmingham district keenly realize this waste. The ores are comparatively low grade and require more fuel than is ordinarily used elsewhere. Hence the flue dust is low in iron content and high in coke. As a result it is not in suitable condition for direct sintering. In many other iron and steel centers direct sintering is a common practice. In the Birmingham district efforts have been made to prevent this loss by recharging the dust into the furnace, but, as might be expected, a material fine enough to be blown out once will very likely be carried over again.In general, the flue-dust losses in this district will average 250 pounds per ton of pig iron produced, but at times the losses at different furnaces are substantially higher or lower than this figure. On the basis of the present rate of pig-iron production, the annual loss of flue dust exceeds 300,000 tons. The iron content of the dust probably averages 25 per cent, therefore about 75,000 tons of iron is wasted yearly, or about 3 per cent of the iron mined is lost in flue dust."

Jul 1, 1926

By Lucia Kuizon

The Cactus Springs Roadless Area Review and Evaluation (RARE II) study area (No. A5188) comprises 12,800 net acres (5,180 ha) in San Bernardino National Forest in west central Riverside County, California, about 20 air miles (32 km) southeast of Palm Springs. Mineral investigations are made by the U.S. Bureau of Mines on National Forest lands identified as Further Planning Areas in the RARE II program. The Bureau of Mines reviewed literature, mining claim records, and production files; examined the study area; and mapped and sampled mineral properties where appropriate.

Jan 1, 1983

By J. F. Barkley

"The fly-ash problem of the smoke-abatement engineer - who now might well be titled, ""Smoke and Fly-Ash Abatement Engineer"" - starts with the necessity for him to know what fly ash really is, what plants really create it, and how much is being created. Fly ash in this connection may be defined as all solid particles emitted to the atmosphere as a result of the combustion of fuel.COMPOSITION OF FLY ASHMuch can be learned about fly ash by studying samples with a strong magnifying glass or, preferably, a high-power microscope. As an example, figure 1 is a photomicrograph of an underfeed-stoker fly ash weighing 23.7 pounds per cubic foot, which passed a baffle-type cinder catcher and was caught by a Cottrell precipitator. Figure 2 shows a similar fly ash made at a higher stoker rating and weighing 36.2 pounds per cubic foot. The lighter ash contains more light, unconsolidated ash than the heavier. In both instances some of the ash has been fused to a glass, as is indicated by the spherical particles resembling marbles; however, the heavier dust contains more and larger spheres. With the faster burning and higher air pressures occurring at the higher burning rates, more of the larger fused spheres reached the precipitator.Such studies of fly ash frequently make possible correct determination of its source. For example, the Supreme Court Building, one of the finest of the Federal buildings in Washington, was having considerable difficulty with fly ash from some outside plant. It was thought to come from a nearby apartment house. A fly-ash trap was installed there, and care was taken in the operation of their underfeed stokers. The fly-ash nuisance continued. Microscopic examination of the fly ash found about the building compared with samples taken from the stack of the apartment house showed to the surprise of the accusing building superintendent that the present source was elsewhere. By the same means, the source was found to be a plant about ore-half mile away."

Sep 1, 1939

By Michael J. Beus

This Bureau of Mines report describes a field experiment involving the sinking of two test shafts to directly compare the deformational behavior of circular and rectangular shapes. Results show that the circular shape is less sensitive to geologic discontinuities and applied stress field. Also, the rectangular shape is subject to a variety of behavioral modes, including beam bending and buckling. Geologic discontinuities around circular and rectangular shapes influence displacement significantly. Simple, two-dimensional elastic finite-element modeling, simulating circular and rectangular shapes in a biaxial stress field, shows that the structural response of a shaft is largely controlled by geologic structure. Consideration of anisotropy may be required for realistic analysis of a deep shaft.

Jan 1, 1985

By W. W. Weller

Heat capacity measurements of anhydrous cobalt sulfate (CoSO4), copper sulfate (CuSO4), nickel sulfate (NiSO4), and zinc sulfate (ZnSO4) were conducted over the temperature range 51° to 298° K. The results were used to evaluate the following entropies at 298.15° K (cal/deg mole): CoSO4, 28.1; CuSO4, 26.8; NiSO4, 24.8; and ZnSO4, 26.4. Entropies were combined with heats of formation to give free energies of formation.

Jan 1, 1965

By W. P. Yant

[This report describes results of a study bf the carbon monoxide and particulate matter in the air of the Holland Tunnel and metropolitan New York made by the Bureau of Mines (which had participated in the development]

Jan 1, 1941

By Pedro Lilienfeld

This report describes a program to develop, design, fabricate and subject to environmental testing three prototype collection-sensing devices of an eventual mining-machine mounted automated monitor for the measurement of the respirable fraction of coal mine dust to determine both short-term as well as average mass concentrations over typical 8-hour shifts. The design of this instrument is based on collection by filtration and mass sensing by beta-radiation attenuation. The emphasis of this development program was to evolve a rugged, stable and reliable collection-detection head compatible with the environment to which An eventual monitor will be subjected. Laboratory testing of this prototype instrument was performed over a representative range of temperature, humidity, dust concentration and composition, shock and vibration. The results of this testing program indicated that the operation of the prototype version His compatible with these environmental conditions and that further development of this configuration into a field operational device is justified.

Jan 1, 1977

By C. M. St. John

A series of analyses of possible mining excavations associated with the development of copper nickel deposits of the MINNAMAX site in Northeastern Minnesota is presented. Specific areas such as roof and pillar stability and excavution orientations are addressed. The majority of these analyses were conducted using a boundary element method but some cases were also analyzed using the finite element method. Comparable results were obtained using the two methods but the boundary element method required less data preparation time and computer run time. Results of the analyses, as well as indicating the capabilities of geotechnical numerical models, provide some insights into behavior around multiple excavations in jointed rock.

Jan 1, 1979

By Edward A. Barrett, Kathleen M. Kowalski-Trakofler

This paper discusses the application of a training intervention that uses degraded images for improving the hazard recognition skills of miners. Method: NIOSH researchers, in an extensive literature review, identified fundamental psychological principles on perception that may be employed to enhance the ability of miners to recognize and respond to hazards in their dangerous work environment. Three studies were conducted to evaluate the effectiveness of the degraded image training intervention. A model of hazard recognition was developed to guide the study. Results: In the first study, miners from Pennsylvania, West Virginia and Alabama, who were taught with the aid of degraded images, scored significantly better on follow—up hazard recognition performance measures than those trained using traditional instructional methodologies. The second and third studies investigated the effectiveness of the training intervention at two mining companies. Data collected over a3—year period showed that lost—time injuries at mines in Alabama and Illinois declined soon after the training intervention was instituted. Impact on Industry: Further exploration of the hazard recognition model and the development of other interventions based on the model could support the validity of the steps in the hazard recognition model.

By J. W. Thompson

CONVEYANCE OF COAL IN PLACES. Coal or other mineral in place may be granted and conveyed as land, separate and apart from that which underlies or overlies it. Board, etc., of Greene County v. Lattas Creek Coal Co., 100 Northeastern, 561 (Indiana), January, 1913. MINERALS SUBJECT OF GRANT. Coal, mineral, and stone under the surface of the earth are the subject of grant and exception, and when excepted in a deed become a separate and distinct inheritance. Gordon v. Million, 154 Southwestern, 99 (Missouri), February, 1913. CONVEYANCE BY ONE COTENANT. One cotenant of land can not make a valid conveyance as against his cotenants of the minerals therein and a right to the small timber on the surface necessary for mining purposes with easements and full rights of way over the premises by the construction of roads, tram- ways, or railroads for the purpose of extracting, storing, handling, and shipping the mineral products. Ball v. Clark, 150 Southwestern, 359 (Kentucky), November, 1912. CONTRACT OF SALE COVENANTS RUNNING WITH LAND. Where a deed was made pursuant to a contract for the sale of certain copper-mining property at an agreed price, and at the same time and as a part of the same transaction a written agreement was

Jan 1, 1913

By John J. Sammarco

As part of a project to automate coal extraction, computer control of a continuous mining machine test bed has been developed and tested by the Bureau of Mines. A computer system and control software were developed for accurate positioning of the conveyor elevation and swing, stabilizer jack, gathering head, and shear elevation. Tramming actions are also controlled by the computer. The computer system was designed to access data from sensors installed on a continuous miner and to interface with the existing control circuits of the miner. Testing in free space was used to characterize the operation of the machine. From this information, control algorithms were written and stored in the computer. The ability to control each function of the continuous miner with a high degree of accuracy and stability was successfully demonstrated in a series of tests in free space and in mining a block of simulated coal. In the mining of simulated coal, the cutting drum was instructed to position the shearer at the top of the block and shear down to the bottom under closed loop control. The cutting drum came within 0.27 in of the top and within 0.49 in of the bottom of the block for this shearing test.

Jan 1, 1988

By R. H. Church, William E. Webb, Walter E. Pittman, James R. Boyle

As part of the Bureau of Mines health and safety research program, a short-range locator system, capable of locating miners who have become trapped following a mine accident, has been devised, The system consists of a lightweight, low-power radio transmitter incorporated into a miner's cap lamp battery and a directional receiver carried by rescuers. Prototype transmitters have been constructed, and the propagation of their signals has been investigated, The detectability of the signal in underground coal mines has also been investigated, This research indicates that a short-range location system would serve as an economical and practical means of locating miners from within the mine following an accident,

Jan 1, 1984

By T. L. Joseph

The Bureau of Mines gas been studying the blast furnace for a number of years and has published detailed reports on various phases of its investigations. Inquiries frequently received for information of a more general character than that given in the detailed reports have promoted the preparation of an information circular to cover in a general way the important features of the Bureau of Mines blast-furnace investigations. SHAPE AND DIMENSIONS OF FURNACE The modern blast furnace approximate a refractory-lined steel cylinder about 90 feet in height and 25 feet in diameter. It actually consists of a number of cylinders and truncated cones superimposed upon each other. The shape and dimensions of a modern furnace are shown in figure 1. The bottom section, commonly referred to as the hearth or crucible, is a cylindrical section about 12 feet high. Liquid metal and slag collect in this part of the furnace and are withdrawn at regular intervals; iron is removed at a level about 2 feet above the bottom of the furnace and slag at a level about 5 feet higher. Depending upon on the size of tie furnace, 40,000 to 75,000 cubic feet of preheated air per minute is introduced through from 10 to 16 tuyeres equally spaced around the periphery of the hearth.

Jan 1, 1934

By Thomas Varley

[For a year or more, statements have appeared in the technical press, and Especially in various trade journals, indicating that valuable metals such as gold, silver, platinum, and other rare metals, have been found and also have been successfully extracted from oil shales. These reports stated tat decarbonization and special methods of chlorination treatment, leaching and subsequent Precipitation, also cyanidation followed by table concentration of the residues after cyanidation, all indicated that told ad silver and other metals could be, and were, successfully recovered. Such articles have caused much misunderstanding, and as the correctness of some re of the statements made in them were questioned by some of the technical journals and by various chemists and metallurgists, an investigation of the subject. was begun by the metallurgical division of the Bureau of Mines, in order, if possible, to determine to what extent, if any, metals of value do occur in oil shales, and if so, the feasibility of attempting their recovery by tie processes said to have been used for teat Purpose. Inasmuch as the Bureau's station at Salt Lake City is investigating the recovery of oil from oil shales, the investigation of too recovery of metals from oil shales was assigned to my direction as superintendent 'of that station. An agreement had been entered into with the owner of m extensive oil shale deposit in Wyoming whereby I would personally collect the samples' of shales for use in the investigation.]

Jan 1, 1922

By Kenneth M. Smith

"The kaolin deposits of Aiken County, South Carolina (fig. 1), have been worked continuously since 1852. It has been long known that the deposits contain a high percentage of alumina and that large reserves exist. These facts led to the early selection of this area for examination in the search by the Bureau of Mines for high-alumina clays. An exploratory program was started by the Bureau, and drilling was carried on from June 27, 1942, to October 31, 1942.The kaolin-bearing district occupies an area approximately 25 miles long and 11 miles wide, running northeast, with its center at Aiken, S. C. (fig. 1). Within this district, a triangular area bounded by Horse Creek, Silver Bluff Road, and Hamburg Road was roughly prospected by boring 43 machine and 12 hand holes. As a result of the data obtained, a final smaller area was chosen for more systematic prospecting. This area is bounded by Pine Log, Tewkesbury, Silver Bluff, and Craig Sawmill Roads and covers about 4,000 acres.Mineral exploration agreements covering 11,272 acres were signed by 35 property owners, and 11,956 feet was drilled in 200 holes on these properties.The Bureau of Mines exploration work in the district has indicated 19,514,000 short tons of kaolin, of which approximately 10,000,000 tons would average over 35 percent alumina.The tonnages and grades of kaolin developed by this exploration are tabulated below.All grades of this kaolin average approximately 2 percent Fe203 and 1.5 percent Ti02.This project was under the general supervision of J. R. Thoenen, supervising engineer, Non-Metals Mining Section of the Mining Division, Bureau of Mines, until July 1942. The -project was then under the general supervision of E. J. Lintner and later Rowe McCrae, consecutively district engineers for Georgia, South Carolina, and Florida. The final report was prepared, under the general supervision of V..J. Lynch, chief, Raleigh Branch, Mining Division, by William A. Beck from the original report by the author.Acknowledgment is made for the wholehearted cooperation and assistance given to the Bureau of Mines by the various operating companies in the district. Particular thanks are due Theodore Henderson, general manager; North American Clay Co., Wilbur Driver, general manager, and Howard Driver, assistant general manager, The Huber Clay Co.; H. W. Smith, president, The South Carolina Clay Co.; and J. Richard Parker, president, J. R. Parker Clay Co., all of Bath S. C.; J. B. Howard, Jr., superintendent/ the Immaculate Kaolin Co., Langley, S. C.; Richard Jones, president, National Kaolin Co., and William Winans, president, The Southern Clay Co., both of Aiken, S. C.; and W. S. Burkalter, Warrensville, S. C.Acknowledgment is also due the Metallurgical Division for analytical determinations and to James J. Page of the Federal Geological Survey for his aid in mapping and logging the holes.The first known use of kaolin from this district was by the Bath Pottery Co., which began mining an outcrop in Horse Creek Valley, near Bath, in 1852.. In 1867, R. McNamee, of New York City, acquired this pit and continued mining. This first mine is still known as the McNamee, and from its operation grew the present kaolin industry of South Carolina."

Dec 1, 1949

By J. R. Thoenen

In Progress Rerort 1,4/ a number of facto were demonstrated and conclusions drawn from experimental tests and records made during commercial blasting operations at a number of quarries. For example, the tests showed (1) that vibrations received on outcrops were of comparatively

Jan 1, 1938

By Doris M. Hyde

The 350,000-barrel-per-day Bahamas Oil Refining Co remained closed throughout 1986. Financially troubled Charter Oil Co., joint owner of the refinery with Chevron Oil Bahamas Ltd., agreed in principle to have Chevron assume full ownership in return for canceling debts owed Chevron. Finalization of the agreement was pending at yearend. Burmah Oil Ltd. took more than a $30 million loss on the sale of its interest in South Riding Point Grand Bahama Transshipment Terminal to South Riding Point Terminal Holding Ltd.

Jan 1, 1988

By J. C. Franklin

A data-acquisition system was designed by the Bureau of Mines to monitor five detectors with radon continuously flowing through each. These detectors could be monitored up to 12 times an hour, but were only monitored according to a preset time, thus allowing radon to be monitored continuously in a uranium mine. The counter can be set to monitor each detector for any period of time up to 16.5 minutes. This allows very low concentrations to be monitored longer to reduce statistical error. There would be no upper limit in radon concentration that could be monitored, but there would be a lower limit of 50 picocuries per liter (pCi/l). Each detector was cylibrated in the laboratory by the Lucas flask method. Multiple samples were taken at two different concentrations, and the correction factor for each detector was determined by a least squares fit of the data. To verify the calibrations, a series of measurements at several concentrations were made against a constant source. Our agreement at low radon concentrations (300 pCi/i) with the two-filter method as within 3 percent; thus, the total error would be this difference plus the two-filter error. At high concentrations the coefficient of variation ranged between 2.1 and 9.8 percent for the five different detector units.

Jan 1, 1976

By D. Harrington, M. W. Von Bernewitz

"Introduction In studying the mine disaster files of the Bureau of Mires for preparation of a bulletin on coal-mine explosions, a table was compiled covering various features of fan installations and the handling of air currents at the time of and after the disasters. As a sidelight on this discussion, there was tabulated the loss of life and number of men injured.Discussion of collected dataOf the 164 disasters tabulated, 148 were explosions, 14 were fires, and 2 involved both fire and explosion. The total loss of life was 4,158 and 412 were injured. There were 145 disasters in bituminous coal mines, 13 in anthratice mines, 2 in lignite mines, 1 in a cannel coal nine, and 3 in metal mines. By States, 35 took place in Pennsylvania; 17 in West Virginia; 16 in Oklahoma and Alabama; 15 in. Kansas and Illinois; 12 in Indiana; 7 in Colorado; 6 in Kentucky; 3 each in Ohio Tennessee and Wyoming; 2 each in Arkansas, Montana, Washington, Virginia, New Mexico and Utah and 1 each in Iowa, Missouri, Maryland, and California."

Sep 1, 1924

By C. F. Wingquist

As part of an ongoing study to determine how the wear of mining tools affects dust generation, the Bureau of Mines has measured bit tempera-ture rise during cutting of abrasive rock. Radial bit wear-flat tem-peratures generated by linear cutting in Berea Sandstone were measured as a function of cutting depth and speed. Depths of cut (DOC) were 1/8, 1/4, and 1/2 in, and cutting speeds were 10, 40, and 80 in/s, respectively. Temperature sensing was accomplished by emplacement of a miniature thermocouple into the center of the wear flat. Temperatures observed ranged from 2000 to 5000 C. Correlation between depth and temperature was weak. Temperature increased linearly with speed at 1/2-in DOC, but data taken at 1/8-and 1/4-in DOC produced inconclusive results. The results indicated that at least for deeper cuts (1/2 in), bit temperature, and therefore wear, can be reduced by lowering the cutting speed.

Jan 1, 1987