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By Fraser M. Walsh

The objective of this program was to determine by laboratory experiments the kinetics and mechanics of the reactions that produce acid in coal mine drainage. The program was divided into three phases: In Phase I, five coil mines, representative of Appalachian coal mines, were chosen for sampling and an experimental design was identified suited to accomplish the program objectives. In Phase II, the five mines were sampled and test protocols applied. The results showed most pyrite weathering to be based on oxidation in the presence of water. Iron bacteria, especially Thiobacillus ferrooxidans, catalyzed the rate of pyrite weathering by a factor of three. An increase in initial iron concentration in a system that modeled the nine environment acted to inhibit bacterial catalysis of weathering. In Phase III, five tailings piles were sampled and the material obtained was used to evaluate this method of bacterial catalysis inhibition. The evaluation verified method effectiveness; inhibition of over 80% of the release of weathering products was observed.

Jan 1, 1982

By Thomas Fraser, J. D. Davis

"INTRODUCTION Preliminary tests of the Oyon coal constituted part of a wartime exploratory and development program in which many agencies participated. The general objective was to find new and adequate source of fuel and other raw materials for greatly expanded industry.The Oyon coal field, known for at least a hundred years to the mining people of Peru, offers a possible source of high-grade process fuel for the growing metallurgical industries of South America and the Pacific coast. Santolalla 4/ reports that low-volatile coal from this region was used in local smelting operations as early as 1850. It has been mined in very small quanti¬ties for many years and used in neighboring mining camps and villages. Small quantities are regularly used at Oroya for the manufacture of carbide, and in recent years small-scale coking operations in specially designed ovens in the region have demonstrated that these coals will make dense coke.During this long period of desultory operations many small openings have been made scattered over a wide area in this general region, indicating very extensive occurrence of the coal measures, although systematic exploration work has not been undertaken. However, current development work of the Banco Minero del Peru has opened up several substantially parallel highly inclined or vertical beds of workable thickness and has followed these deposits to sufficient lateral extent to prove fairly well the existence of substantial reserves on this property."

Mar 1, 1948

By Larman J. Heath

Preliminary results of an explosive fracturing-solvent injection heavy oil recovery experiment conducted by the Bureau of Mines at a shallow oil reservoir near Bartlett, Kans., are given. Three wells 35 to 50 feet apart were drilled to a depth of 360 feet, and an open hole interval from 300 to 350 feet in the Bartlesville Sandstone Formation was explosively fractured with 3,000 pounds of pelletized TNT in each well. Laboratory tests were made on cores obtained from these wells to confirm the suitability of using an aromatic-type solvent. Injection of a 74-percent aromatic solvent was begun into one well and continued intermittently for approximately 2 months. Crude oil production amounted to 29.6 bbl, or 11.7 percent of the total oil con¬tained within the three-well interwell zone.

Jan 1, 1972

By Elizabeth G. Baglin

Research was conducted by the Bureau of Mines to determine the feasibility of using electrokinetic densification to dewater Bayer process red mud, magnetic black mud prepared by pressure digestion of red mud in the presence of ferrous sulfate, and magnetic black mud formed by simu-lated Bayer digestion of Jamaican bauxite with added ferrous sulfate. Tests showed that the solids content of presettled muds could be increased from 25 pct to approximately 40 to 48 pct by gravity draining followed by electrodewatering for approximately 48 h. Electrodewatering may not be practical because of increased reagent and processing costs and because the muds must be thoroughly washed prior to electrodewatering to remove dissolved ions and decrease mud conductivities.

Jan 1, 1988

Develop and evaluate a mechanical position and heading system (MPHS) that provides information about underground mining machine position and heading to aid in the remote positioning of mining machines during face maneuvers. Background While great improvements have been made in mineworker safety, progressive technology continues to create a safer, better working environment for miners by keeping them away from the dangerous face area. In maintaining such high standards of safety, the Bureau is investigating remote, computer-assisted operation of mining systems for underground, highwall, and surface mining applications. A key component of computer-assisted operation is a guidance system. Since there are no guidance systems on any commercial continuous mining machines, the Bureau itself developed and tested the mechanical position and heading system (MPHS). The MPHS is based on linear position transducers (LPT's), and operates on principles of triangulation to provide machine position (xy coordinate), and orientation in the xy plane (yaw or heading). These data are needed in order to keep the continuous mining machine in proper alignment before and during the cutting cycle. The MPHS theory development is in three parts: characterize the sensors used and their configuration; select and define the navigation reference frames; and derive a closed-form solution for determining the position and beading from sensor information. Application of the MPHS theory required the development of hardware, software, and system interfaces.

Jan 1, 1992

By J. L. Konchesky

The technical feasibility of gasifying powdered, noncoking, low-rank coal with steam in an externally heated tube has been demonstrated. The tube, 112 ft. of alloy-steel tubing shaped into a helix, served as an electrical conductor of electricity used for heating. The effects of the following variables were studied: Residence time of coal in reactor, average reaction temperature, steam concentration, and rank or geologic age of coal. Reaction pressure was maintained in the range 19-26 p.s.i.a. High carbon conversions and large yields of synthesis gas were obtained with low-rank coal. In one test, for example, about 88 pct. of the carbon in a subbituminous C coal was gasified at 1,910* F. with a residence time of 1 sec. The gas contained 58 pct. H2, 19 COD 15 CO, and 3 CH4; the yield was 30 cu. ft. (at 32' F. and 14.7 p.s.i.) of synthesis gas (CO + H2) per pound of dry coal.

Jan 1, 1960

By Bertrand L. Johnson

Langbeinite, a comparatively rare mineral that has been reported from only five countries in the entire world, has recently attained considerable economic importance in the United States and Poland. Since September 1940, several hundred thousand tons have been produced in one of the Carlsbad (N. Mex.), potash mines for chemical and fertilizer use. As it is a newcomer in this field, and as it is the source of fertilizers possessing special advantages, notably for soils deficient in magnesium or requiring sulfate fertilizers, a discussion of its properties, occurrences, uses, mining, and treatment is appropriate at this

Jan 1, 1944

By E. L. Rawlins

Systematic leakage surveys of natural-gas transmission lines not only aid in the conservation of gas, but can be made to show direct financial returns of large magnitude. 1. Such surveys reveal the actual leakage from the lines, and indicate repairs to be made in order, to eliminate unnecessary waste. 2. Tests on lines, after repairs are made, show the actual saving that has been accomplished. 3. Tests on newly constructed lines reveal the presence of leakage that should be eliminated before the lines are put into service.

Jan 1, 1926

By J. Tomlinson

Shuttle car trailing cable splices were tested for resistance to failure upon being subjected to repeated bending, abrasion, and tensile shocks using a new testing method that closely simulates shuttle car induced stress. The results show that under normal stresses, splices can be made to withstand the equivalent of three months of operational use. Restoring the tensile strength to the conductors is found to be as critical as restoring flexibility. Splices in which the conductors are of slightly unequal length did not present as serious a workmanship problem as previously thought since test results show that the conductors tend to equalize when longer cables, in contrast to short cables employed in previous testing methods, were used. Dynamic recordings of cable tensile stresses are presented for a shuttle car and the new simulated testing method. Two simple but effective methods for removing insulation using a knife and a pair of pliers are described. None of the designs tested for a sacrificial splice covering were satisfactory.

Jan 1, 1979

By Seth T. Reese

THE INJURY DATA and experience at coal mines in the United States for 1951 are presented in this bulletin under the following general heads: (A) General injury experience: Tables 1 to 18: Contain current data on number of fatalities and nonfatal injuries, frequency and severity rates, average severity, major and detailed injury agencies, and distribution of injuries by part of body and days of disability. (B) Selected injury data: Tables 19 to 43: Contain current data on various selected factors of operating and physical conditions that contributed to the occurrence of injuries at bituminous-coal, lignite, and anthracite mines. These factors include extent of hand and machine loading, size of mine by employment and production groups, thickness of bed or vein, duration and number of work shifts, rating of mine as gassy or nongassy, types of cap lamps, explosives, and combination of factors that influence mine safety. (C) Injury experience by States: Tables 44 to 50: Contain current data on number of fatalities and nonfatal injuries, frequency and severity rates, average severity, major causes and principal agencies, injury records of all coal-producing States, and the relative standing by States according to injury-frequency rates. (D) Major disasters: Table 51: Lists the coal-mine disasters that occurred during 1951, giving location, source, and cause. A major disaster in coal mining is defined as a single accident in which or as a result of which five or more men lost their lives. (E) Historical coal-mine injury experience: Tables 52 to 86: Contain data on injuries, injury-frequency rates, employment, and production at bituminous-coal, lignite, and anthracite mines from the earliest records through 1951.

Jan 1, 1955

By H. C. Ko

Calorimetric determinations of low-temperature heat capacities and standard enthalpy of formation were made by the Federal Bureau of Mines for basic aluminum sulfite, A1203?2.0S02?5.3H20. The standard values of entropy (S°), enthalpy of formation (?Hf°), and calculated Gibbs energy of formation (?Gf°) at 298.15 K are 85.2±0.1 cal/deg-mole, -943.1±1.2 kcal/mole, and -820.7±1.2 kcal/mole, respectively.

Jan 1, 1976

By E. J. Matson

This report covers the investigation of the MacArthur copper deposit and several adjacent claims in the Mason mining district; Lyon County, Nev. (fig. 1). As a part of the Bureau of Mines program of investigation and development of domestic mineral deposits, a project was begun first on the MacArthur claims. Work was done later on some adjacent claims in the immediate area, as shown by figure 2. Field work was begun by the Bureau of Mines on January 16, 1950, and completed on October 25, 1950. Eight diamond-drill holes were completed, for an aggregate of 3,414 linear feet, Analyses were made of' each drilling interval. The report includes a brief history of the district and a description of the deposits and of the work done by the Bureau of Mines.

Jan 1, 1952

By P. L. Woolf

Two blast furnaces, one a. commercial furnace and the other the Bureau of Mines experimental furnace, were successfully operated with extremely low slag volumes. The lowest slag rate obtained on the industrial furnace was 335 pounds per ton of metal. Using the same burden materials a 245-pound slag volume was achieved on the furnace. The coke rate saving and increase in productivity resulting from lowered slag rates are discussed as well as the factors limiting a low slag practice.

Jan 1, 1965

By H. L. Gilbert

Zircon sand may be reacted with sodium hydroxide at 600° C. to form sodium zirconate and sodium silicate. Sodium zirconate is water insoluble and so may be washed free of sodium silicate. The sodium zirconate may then be converted to zirconyl chloride by the action of hydrochloric acid and the zirconyl chloride crystals separated by cooling the solution. This approach produces zirconyl chloride of satisfactory purity with less cost than is involved in buying anhydrous zirconium chloride and converting it. A proposed design for a plant is given, INTRODUCTION This work was conducted by the Rare Metals Branch as a part of research on zirconium at the Bureau of Mines Northwest Electrodevelopment Laboratories, Albany, Oreg., under the guidance of S. M. Shelton, Regional Director. The work was supervised by W. W. Stephens, head of the Rare Metals Branch (now with Carborundum Metals Corp.).

Jan 1, 1954

By K. E. Soroka

More than 500 fires are now burning in abandoned coal waste banks and coal deposits in the United States. Once established, such fires can burn for decades, and extinguishing them by conventional methods such as surface sealing to exclude air, excavation to remove fuel, or flushing to cool the fire zone is usually difficult and always expensive. Burnout Control, a technique developed by the Bureau of Mines for the control of abandoned coal fires, involves the accelerated combustion of coal in place with total management of the heat and fumes produced. A burning waste bank or mine is placed under negative pressure relative to the atmosphere, and heat and combustion products are drawn from the combustion zone through an exhaust ventilation system. Heat produced appears as sensible heat in the exhaust, at temperatures as high as 1,0000 C (1,832° F), and could be recovered for the production of steam, hot water, process heat, or electricity. The Bureau's first held field demonstration of Burnout Control was at Calamity Hollow in Allegheny County, PA (near Pittsburgh). Calamity Hollow was the site of an underground mine in the 1900's and was surface mined in the 1940's. In the winter of 1961-62, a fire of undetermined origin was discovered in the exposed coal. In 1963, the Bureau constructed a trench barrier around the fire and a surface seal over the affected area. The fire was isolated but not completely extinguished. In 1979, when the Bureau began work on the Calamity Hollow Mine Fire Project to demonstrate controlled burnout, the fire was still smoldering on the hot side of the trench barrier. The project, which was begun in December 1979 and ended in July 1982, consisted of the design, construction, operation, and subsequent dismantling of a Burnout Control ventilation system. This report is the fifth in a five-part series that describes the Calamity Hollow Mine Fire Project. The first report, part 1, describes the design and construction of the field installation. Part 2 will present the results of a continuous 4-month burnout operation. (Because part 2 involves the analysis of a substantial body of data, it will not be published until after publication of parts 1, 3, 4, and 5.) Part 3 describes the instrumentation used to control and monitor the progress of the burnout operation. Parts 4 and 5 deal with the closeout phase of the field demonstration. Part 4 describes the procedure used to quench the fire, and this part (part 5) describes the final excavation and backfilling of the heated zones. The reports in this series document the Calamity Hollow controlled burnout demonstration which showed that (1) controlled in situ combustion is a feasible method for controlling underground fires in abandoned mines, (2) the resultant thermal exhaust output is sufficient for energy utilization, and (3) water injection-fume exhaustion is a potentially effective method for cooling large underground fire zones. Further investigations of both Burnout Control and the water-injection-fume exhaustion quenching procedure are planned.

Jan 1, 1986

By W. W. Agey

The Bureau of Mines examined and tested the rhodonite deposits of the Silverton lead-zinc district, San Juan County, Colo., as a possible source of domestic manganese. Exploration and development work by several mining companies and preliminary reconnaissance of the area by Bureau of Mines engineers indicated the presence of extensive manganese resources in the form of rhodonite. This report summarizes the results of laboratory beneficiation tests made on samples of different type and grade material obtained from surface and underground exposures of seven veins in the district. Surface and underground examinations revealed the presence of several prominent veins that could be traced up to 2 miles for a single vein along the surface. The principal veins average about 50 feet in width and apparently carry rhodonite to considerable depth. Underground samples were taken from the Sunnyside, Silver Queen, Washington, Independence, and Scotia veins. Samples also were taken from surface exposures of the Sunnyside Extension and Hidden Treasure veins.

Jan 1, 1962

By Stanton L. Tainter

"As an adjunct to its minerals-investigation program, the Bureau of Mines has developed a number of operating devices and techniques worthy of note. This paper, prepared under the supervision of J. H. Hedges, chief, Tucson Branch Mining Division, and under the general supervision of Lowell B. Moon, chief, Mining Division, reports upon certain methods devised to overcome difficulties encountered in cementing of diamond-drill holes at a Bureau of Mines project at Christmas, Gila County, Ariz.Pressure grouting was employed to recondition a caved hole it was desired to reopen and deepen. The hole, which had boon stopped 7 months previously at a depth of 488 feet, was caved below 449 feet in a contact zone of claylike, altered diorite and crumbly metamorphosed limestone. As other means of obtaining moderate pressure were not available, carbon dioxide gas, drawn from tank of liquid carbon dioxide through a pressure reducing and regulating valve, was used. The hole was reopened successfully with 12 grouting jobs.Another hole, where cawing from several water-bearing fractures between 202 and 232 feet gave trouble, was successfully cemented by the use of a grouting plug. An attempt to cement through the rods had failed, owing probably to agitation caused by water currents. Pressure grouting through the caning set above the cave could not be need, because water was forced up outside the casing when pressure was applied. The problem was solved by using a wooden plug 1-13/16 inches in diameter, which, when soaked in water, expanded to a tight fit in an AX hole. A hole was drilled through the plug, and a rubber flap valve was nailed to the lower end. In the upper end of the plug the hole was enlarged to fit loosely over an EX rod coupling finished smooth. The plug was lowered on the end of the drill rods to a point about 10 feet above the cave, where it was allowed to expand tightly to the hole. Cement grout was then pumped through the rods, and the rods were removed from the hole. After allowing time for the cement to set, the wooden plug was chopped out and drilling van resumed.Over 300 tests were made to determine the type of cement most suitable for use on the Christmas job, and the effect of cement-water ratio, temperature, and various admixtures on workability, setting time, and strength. The results of these tests, described in detail in the body of this report, indicate the desirability of thoroughly testing available cements when it is necessary to drill holes under difficult conditions that may cause failure.When it became desirable to reopen and deepen a caved drill hole, it was considered easiest to recondition the hole by pressure grouting, As other mans for obtaining moderate pressure were not available, a method utilizing carbon dioxide gas was employed. The hole was reconditioned successfully with 12 grouting jobs."

Nov 1, 1949

By A. T. Tye

This paper describing the concentrator practice of the Cananea Consolidated Copper Co. at Cananea, Sonora, Mexico, is one of a series of articles on milling methods and costs being prepared by the U. S. Bureau of Mines. The Cananea concentrator treats 2,400 tons of copper ore per day by preferential flotation, whereby the copper sulphides are floated and the iron pyrite depressed. During the first half of the year 1929 the heads to the concentrator averaged 3.29 per cent of copper, the recovery was 95.74 per cent of the total copper, and the concentrates produced contained 21.44 per cent of copper.

Jan 1, 1930

By B. K. Shibler, K. C. Vincent, W. W. Agey

"INTRODUCTION As a part of the investigation of domestic manganese deposits, examining engineers of the Bureau of Mines collected samples of ore from three from three properties in the general vicinity of Tracy, Calif.The Buckeye mine is 23 miles of Tracy, just inside the northeast boundary of Stanislaus County. The mine is owned by K.O. Winship estate of San Francisco and is leased by Verner Allen, also of San Francisco.The ore is principally manganese carbonate occurring in interbedded layers in white chert, with the original,carbonate mineral altered in place. Four samples, representing four types of ore, were submitted, as follows: A, black oxide; B, pink carbonate; C, gray carbonate.The Wilfred Murphy property (also known as the Murmac claims) is approximately 30 airline miles south of Tracy. The property can be reached by road from either Livermore or Patterson and is on the divide separating Santa Clara and Stanislaua Counties Calif. The ore occurs in lenses along a white-chert formation. A 2-ton sample of ore for testing was taken from a dump accumulated from assessment and development work. The Ladd mine, 13 miles from Tracy in San Joaquin County is owned by Pat J. Connolly of Tracy and is leased by Mack C. Lake of San Francisco. The ore is essentially a chert impregnated with manganese oxides and the association is therefore exceedingly intimate and complex. Samples from each of the three adit levels of the mine were submitted for ore-dressing study.As the samples differed widely in physical character and response to ore-dressing methods of treatment, beneficiation of ores from each property was considered as a separate problem. Hence results of the investigations will be prescribed in separate sections of this report."

Nov 1, 1947

By William W. Adams

The quarrying and related industries of the United States improved their safety record in 1938 by reducing their accident-frequency rate to a lower acid more favorable position than it has occupied at any time except 1935 since comparable accident statistics became available in 1916. The rates for 1935 and 1938 were identical. The number of men employed in 1938, although smaller than in 1936 and 1937, was larger than in any other year since 1930. Volume of employment, as measured by the number of man-hours worked in the industry as a; whole, likewise was larger than in any year since 1930 except 1936 and 1937. Reports from operating companies to the Bureau of Mines, United States Department of the Interior, showed that 77,497 men were employed in 1938, a decrease of 6,597 compared with 1937. This figure represents the average number of employees for the period during which the quarries and plants were active during the year, which in 1938 averaged 223 workdays per employee compared with 241 in 1937. A total of 17.3 million man-days or 133.8 million man-hours of work was shown for the industry as a whole, which indicated a weighted average of 7.75 hours per man-shift. Reports for 1937 showed a total of 158.3 million man-hours for the entire industry and an average workday of 7.81 hours. Accidents resulted in the death of 82 employees, 5 more than in 1937, and in 5,027 nonfatal injuries involving disability for more than the remainder of the day on which the injuries were received. The number of nonfatal injuries was 1,321 less than in 1937. As the number of deaths and injuries was reduced more, proportionately, than man-hours of employment, the accident-frequency rate per million man-hours of work declined, the rate for 1938 being 38.19 compared with 40.59 for 1937. In other words, accident occurrence to the average employee was 6 percent more favorable in 1938 than in 1937 on the basis of actual number of accidents and actual number of man-hours worked during the 2 years.

Jan 1, 1940