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By E. S. Longfellow, S. H. Katz

Poisonous hydrocyanic acid gas (HCN) is sometimes evolved in dangerous quantities from cyanides used in metallurgical and chemical operations. This gas is much used for fumigating buildings, ships, greenhouses, and such commodities as grain and cotton to destroy rats, mice and insect pests. Wherever cyanide fumes are evolved, thorough ventilation is necessary in order to render the sur- rounding air safe to breathe. Many persons have been killed by entering tanks and fumigated places too soon, and a simple test for this gas would promote safety. In view of the need for an easy method for quantitatively determining HCN in air, the three color reactions used originally for testing HCN in solution tions *** were modified and adapted. The reactions employ (1) picric acid (CH(NO2)3OH) which is yellow but combines with hydrogen cyanide to form a red- purple dye, isopurpuric acid****; (2) phenolphthalin (CH1604), which is a reduc- tian product of the phenolphthalein (CH4) used for acid indicator, this colorless substance is oxidized***** by presence of HCN to pink colored phenolph- thalin; and (3) guaiacum which oxidized from colorless to blue******. Phenolph- thalin and guaiacum require the presence of copper compounds which catalize the color formation by reduction of cupric cyanide. The chemical processes involved *Associate physical organic chemist, Bureau of Mines, Department of the Interior. **Assistant gas chemist, Bureau of Mines, Department of the Interior. 2014 20 *** Kohn-Abrest, E., Notice toxicologique sur les gas: Arnales des Falsifica- tions, vol. 8, 1915, pp. 215-35. (Tested air with picric acid and guaiacum papers). **** Élasiwietz, H., Ueber eine neue Zersetzungsweise der Trinitrophenylsaure: Anal. der Chemie, vol. 110, 1859, pp. 289-303. ***** Weehuizen, F., Phenolphthalin as reagent for HCN: Pharmaceutrisch weekblad, Utrecht, vol. 42, 1905, pp. 271-2. Abstract, Jour. Chem. Soc., vol. 88, part 2, 1905, p. 489. ****** Schonbein, C. F., Ueber den thatigen Zustand der Helfte des in dem Kupfer- oxydenthaltenen Sauerstoffs und ein darauf beruhendes hochst empfindliches Reagens auf die Blausaure und die loslichen Cyanmetalle: Jour. fur. Praktische Chemie, vol. 106, 1869, pp. 263-70.

Jun 1, 1923

By C. J. Wilhelm

The Bureau of Mines, under its cooperative agreement with the Kansas State Board of Health, has been conducting a study of the various methods of oil-field brine disposal in the oil fields of Kansas. A previous report5/dealt with this problem in the Ritz-Canton field, McPherson County, Kans. A preliminary survey of the Arkansas River drainage area in western Kansas was made during November and December 1934 and January 1935, and a second survey was made approximately one year later during the months of December 1935 and January and March 1936. In addition to the data on the production of oil and 'brine in the various fields and the methods used for handling the brine, the surface drainage and character of the surface soil in the various oil-producing areas were studied.

Jan 1, 1936

By H. R. Babitzke, H. Kato, R. E. Siemens

An investigation was made to provide further information for evaluating columbium- hafnium alloys for use as high - temperature structural materials . The columbium- hafnium system was investigated between 700 ° and 2,400 ° C by melting point , thermal analysis , X - ray diffraction , electrical resistivity , and metallographic techniques . The equilibrium diagram is the beta isomorphous type , with columbium tending to stabilize the beta phase . Addition of 60 atomic percent columbium stabilizes the beta phase at 700 ° C. The allotropic transformation temperature of hafnium is 1,750 ° ± 20 ° C. A minimum melting point occurs near 75 atomic percent hafnium .

Jan 1, 1964

By J. J. Shields

With the increased use of mechanized equipment in mining bituminous coal, production panels are mined out rapidly. To keep current with the rapid completion of production panels, development work must be speeded up also. Although the same type of equipment usually is employed in development as in production places in the same mine, past output per man for development usually was less than from production panels. A study of development practices in 14 mines reveals a tendency toward equalization of the output per man between development and production.

Jan 1, 1957

By William A. Sloan

"In smelting operations, finely divided material called ""flue dust"" is carried by the moving gases from the roasters and furnaces; it is partly settled and recovered in the flue system. The flue dust from copper smelters contains a high percentage of copper, usually some gold and silver, and occasionally other valuable metals. It is too valuable to throw away and in present practice is returned to the smelting furnaces for re-treatment. A part of this material again passes out with the gases and forms a circulating dust load in the system. The dust that passesout of the stacks into the atmosphere is an important source of loss in copper smelting. Loss of values also occurs by dust being blown away while in transit from the flues back to the furnace, and of course the greater the amount of rehandling the greater this loss.Dust carried in the gas currents causes corrosion of the roof arches in reverberatory furnaces. Returning flue dust to the furnace increases the quantity of suspended dust. Corrosion reduces the life of the arches and shortens the length of furnace campaigns; also the corrosion of arches limits the temperature at which a furnace may be operated. Every ton of material that must be re-treated in the furnaces reduces correspondingly the amount of new ore or concentrates that could be smelted.As the present tendency is toward finer grinding in flotation plants smaller particles will need to be treated at the smelters, increasing the difficulty of preventing losses in flue dusts. Many schemes and processes for a more economical method of treating flue dust have been proposed or tried, but in the main none of them has been successful."

May 1, 1928

By L. J. Froisland

The U.S. Bureau of Reclamation requested U.S. Bureau of Mines (USBM) assistance in developing design data for moving lead-zinc-gold tailings from their current location without disrupting the existing chemically stable conditions. This report presents results of USBM work in determining (1) the minimum required time to air dry the tailings to approximately 20 pet moisture under various drying conditions both in the laboratory and in the field, (2) the degree of oxidation or reduction that occurs during drying, (3) the effect of lime or cement addition before drying, and (4) the likely equilibrium conditions of the dried tailings after deposition at the new location. The limited number of tests performed by the USBM in the available time frame established trends in oxidation levels but did not provide absolute statistical validity of data values. All data from drying and oxidation testing are included in appendices to this report.

Jan 1, 2010

By Charles L. Kusik

As part of an effort to establish the extent of the domestic chromium supply that could be exploited in case of adverse changes in international chromium production and trading patterns, a two-part study was conducted for the Bureau of Mines, to assess the domestic availability of critical metals in scrap containing significant amounts of chromium. This report describes the part of the study that deals with wrought stainless steels and heat-resisting alloys. Data were collected on types of scrap, sources, quantities, and ultimate disposition, leading to the conclusion that In 1917 about 62,000 tons of contained chromium was unrecycled. Unrecovered obsolete stainless steel scrap accounts for most of these uncollected chromium values. Error margins in the amount of uncollected scrap are estimated to be 10 to 20 percent.

Jan 1, 1980

By T. M. Garland

This report presents a more extensive perspective of the calculated profitability of developing and producing crude oil and associated natural gas by primary methods from selected onshore areas of the United States. Estimates were made for cost of drilling, completing, equipping, and producing oil wells at four depths in seven onshore producing areas. A computer program was developed for calculating the discounted cash flow rate of return for the 64 different models in each area resulting from varying the oil-producing rate and production decline rate. The results of these calculations provide data that vividly illustrate the change in rate of return to changes in well depth, initial producing rate, and production decline rate, as well as to variations in development cost and operating expense. Cost per barrel of oil produced in terms of annual cost and total cost is also discussed. Included in the report are explanations of the method of determining costs and the procedure used for profitability analysis. Summaries of all cost estimates and results of profitability analyses are presented in the appendix in tabular form for each of the seven producing areas.

Jan 1, 1972

By Charles Seitz

The Bureau of Mines has modified its parts-per-billion helium-4 analyzer to improve the analytical capabilities of the instrument. The modifications resulted in the following improvements: (1) The analytical precision of the instrument for 10 consecutive analyses was improved to ±1 ppb at the 5,000-ppb helium-4 level, (2) the helium-4 sensitivity was increased almost tenfold, and (3) the minimum detectable limit for helium-4 was improved to 0.5 ppb. The modifications made to improve the instrument included replacing the ion-source control circuit with a direct-current solid-state design, controlling the temperature of the ion source, stabilizing and reducing the pumping rate of the vacuum system, and optimizing peak integration.

Jan 1, 1986

By N. A. C. Smith

This report on the physical and chemical properties of typical crude oils of southern Louisiana and southern Texas is the seventh in a series of preliminary chapters of a bulletin covering the producing districts of the United States. Preceding reports* may be obtained from the Bureau of Mines on request. The details of the methods used in this survey in collecting samples and making laboratory tests have been discussed in the first three papers. A method of summarizing and interpreting the laboratory data has also been given, but most of the crudes included in the present report differ so radically from those previously reported, that it has been found advantageous to adopt a somewhat different method in making summaries. This method is described in detail later. If any errors or omissions are noted by readers, it is hoped that these will be brought to the attention of the Bureau of Mines, for correction before the appearance of the final bulletin.

Jan 1, 1922

By J. Drew Potts

In this U.S. Bureau of Mines study, four underground respirable dust surveys were conducted to determine factors affecting belt entry dust levels and how using belt air to ventilate work areas affected dust exposures. Belt entry dust levels on the surveyed longwall and continuous miner sections averaged 0.59 and 0.26 mg/m3, respectively. The stageloader-crusher contributed an additional 0.5 to 0.9 mg/m3 of dust to belt air, while the feeder-breaker contributed 0 to 0.2 mg/m3 of dust. A 1,000-ft increase in belt entry length or a 200-to 500-st-per-shift increase in production resulted in roughly a 0.1-mg/m3 increase in dust. Using the belt entry as an intake entry on the continuous miner section appeared to reduce dust levels by 0.1 to 0.3 mg/m3 during cutting. Belt air was not used to ventilate the face on the longwall section.

Jan 1, 2010

Provide blasting-resistant, quickly reusable stoppings for large mine openings. Approach Stoppings are assembled using roof-to-bottom panels of brattice held together by Velcro seams that peel open when struck by a strong air blast. How It Works The Velcro seam is designed to open when exposed to forces lower than would normally damage the brattice. When the seams partially open, they relieve the blast air overpressure to prevent damage to the brattice panels and their anchoring devices. A stopping is returned to service by reclosing the Velcro seams. To hang a brattice panel, its top is stapled to a board, and wrapped once or twice around it. That assembly is then attached to the roof with bolts. The length of the board should be a foot less than the width of the panel to allow for the sealing seam on each side of the panel. The boards are installed end-to-end in an approximately straight line across the roof of the mine opening.

Jan 1, 1979

By Alan D. Hartman

Standard metering of electric arc furnaces usually uses root mean square (RMS) or true root mean square (TRMS) measurements for determining power. Only sinusoidal signals are accurately described by RMS meters, and dc or high-frequency components normally are lost in standard TRMS metering. This can lead to inaccuracies when electrical signals are not sinusoidal, contain dc components, or include fast risetime perturbations, as is the case with the electric signals from an electric arc furnace. Electric arc furnace electrical waveforms, observed in research carried out by the U.S. Bureau of Mines, show high-frequency components and significant deviations from sinusoids. These perturbations and distortions make metering difficult for standard power meters. The inaccuracies in metering can cause further problems if those sensors are used in control systems. For control strategies requiring rapid response, any averaging scheme loses information that can be used in control decisions. In order to obtain better signals for both monitoring and control, a study of instantaneous, RMS, and TRMS power monitoring devices was conducted. From this study it was concluded that precision integrated circuits should be used to obtain instantaneous power with a bandwidth of at least 25 kHz. The information from these devices is more representative than that of standard meters and can be used in predictive control.

Jan 1, 2010

By Robert R. Stein

Using an automated drill test fooure, the U.S. Bureau of Mines measured the sound power levels produced by a small, pneumatic, rotary roof drill. A series of tests was conducted to determine (1) the relative effectiveness of several drill muffling schemes and (2) the relationship between drill sound power and pneumatic power supplied to the drill. The influence of rotation rate (i.e., airflow) and feed thrust on the penetration rate of the drill was also noted.

Jan 1, 1989

By John E. Miller

A high accuracy Burnett apparatus for use at 12,000 psi and 0° to 65° C has been constructed at the Bureau of Mines Helium Research Center. The apparatus is patterned after Burnett's original apparatus, but the working pressure is much higher and elastic distortion can be essentially eliminated. An operating procedure to permit faster experimental measurements is suggested.

Jan 1, 1967

By R. V. Ramani, R. Bhaskar

"The control of respirable dust in mines has been given paramount importance due to the health and safety implications associated with fine dust. The understanding of the temporal and spatial behavior of dust has been recognized as essential for increasing the efficiencies of the existing control techniques and for developing new control strategies. Mining-related studies in this area are, in general, limited. They are also mostly experimental. Some mathematical and computer analyses have been attempted. In this paper, first a review of the mathematical studies performed in the last three decades in this area is presented. Second, a mathematical model for analyzing dust flow in mines is proposed. The model takes into account a number of factors affecting dust transport. It incorporates varying dust generation source strengths and dispersion, deposition, and coagulation of dust in mine airways. Finally, application areas for the model are discussed. A computer program based on the mathematical model has been developed. The program will output the dust concentration in the mine atmosphere as a function of time and distance from the source. The amount of dust deposited on the sides, roof, and floor of the airway is also determined.IntroductionAn airborne dust cloud is a complex system containing particles of varied size, density, shape and state of aggregation. The behavior of the particles is dependent on a number of complex physical mechanisms, often opposing in nature. The net interaction results in the ambient concentration. This size dependent behavior of particles contrasts with that of gases, an area quite widely studied.The term aerosol is used to describe clouds of microscopic and submicroscopic particles in air such as chemical smoke or particulate matter released from smoke stacks. An aerosol system can be regarded as an arbitrary element of volume filled with gas and suspended particles of possible highly variable physiochemical nature. The parameters that are used to describe an aerosol system include concentration, mass average velocity and particle mass and radius. In characterizing such systems, several assumptions are made. Among these is the assumption that particles are smooth, inert and rigid spheres. Again, for example, when the particles are in transport, the possibility of collision exists. As a result of the collision, the particles may coalesce to form larger particles. The probability of sticking is considered a known quantity (lady, 1970). In this paper, the application of the principles used in aerosol systems is explored for the study of the transport and deposition of fine coal dust in underground mines."

Jun 1, 1988

By Raymond B. Ladoo

The Bureau of Mines frequently receives requests for information on the mining , preparation and marketing of epsomite or Epsom salt , and in order to answer such inquiries the following information has been compiled . While it is probable that few people have considered epsonate as a mineral product , it will be noted that it should be so regarded and its production forms an important industry .

Mar 1, 1922

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 Frank A. Peters

A series of evaluations is being made to determine the relative processing costs of producing metallurgical-grade alumina from low-grade aluminous materials. These evaluations include the estimated operating and capital costs as well as recommendations for additional research and development to improve the processes and to lower their costs. The design for each process is based on published work. The three processes considered in this evaluation are designed to leach alumina as aluminum sulfate from calcined clay with sulfuric acid and to remove the silica residue by filtration. The filtrate from leaching is then purified by one of the following methods: Removal of iron in electrolytic cells using mercury cathodes; removal of iron by chemical precipitation through the formation of an iron-manganese complex; or precipitation of the alumina from an aqueous-ethanol solution, leaving iron in solution. Both the operating and capital costs for these processes are higher than those for the Bayer process. For plants producing 1,000 tons of alumina a day, the estimated operating costs per ton of alumina are: Electrolytic iron-removal process........... $81.35 Chemical iron-.removal process............... 82.08 Ethanol purification process............... 86.17 The investment in mercury is not part of the operating cost since this cost is considered equivalent to catalyst cost which would not be shown. The estimated capital investments for 1,000- ton-per- day plants on a Marshall and Stevens chemical equipment index basis of 240.0 are: Electrolytic iron-removal process...... $116,775,500 Chemical iron-removal process............... 99,418,900 Ethanol purification process................ 94,210,200 These investments include the working capital but not the land for each of the processes. Included in the electrolytic iron-removal process is an investment of $4,859,400 for mercury. Investigation of other methods for removing iron, of the decomposition operation, and of the leaching operation could reduce these costs.

Jan 1, 1963

By A. Soderberg

This paper describing the mining practice at the Utah Copper Co., Bingham Canyon, Utah, is one of a series being prepared by the Bureau of Mines on mining practices, methods, and costs in the various mining districts of the United States. The Utah Copper Co. operates the low-grade open-out copper mine at Bingham Canyon, Utah, which is 30 miles in a southwesterly direction from Salt Lake City. In addition to the mine the company operates two flotation concentrators, the Magma plant and the Arthur plant, which have a combined capacity at maximum metallurgical efficiency of 60,000 tons daily. The concentrators are at Magna, about 18 miles from the mine. The company operates its own standard-gage railway, known as the Bingham and Garfield Railway, between the mine and the mills (fig. 1). Concentrates are smelted at the Garfield smelter of the American Smelting and Refining Co., situated 4 miles from the mills.

Jan 1, 1930