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By J. E. Tiffany, Gaigler. Z. C.

"PREFACEIn presenting this list of permissible explosives and blasting devices, the Bureau of Mines desires to call attention to pages 16 and 21 outlining the conditions in use under which, and only under which, the explosive or blasting device is permissible.In view of a recent publication recounting trade practice favoring the use of a blasting device without stemming, particular emphasis is placed upon condition 4 on page 16 and condition 2 on page 21. An explosive or a blasting device enumerated in the permissible lists of this Bureau is not permissible in use unless it is properly confined with clay or other incombustible stemming.PERMISSIBLE EXPLOSIVES TESTED UNDER SCHEDULE 17CAn active list of permissible explosives was published in December 1937 as part of Bureau of Mines Report of Investigations 3361, under the title ""Active List of Permissible Explosives and Blasting Devices Approved Prior to June 30, 1937.n This list included 196 brand names.Changes in the list that have been authorized to June 30, 1938, placed 7 additional brands of permissible explosives on the active permissible list as a result of tests, changes in brand names, or transfer from the inactive list. Twelve permissible explosives were transferred from the active to the inactive list. The present list contains 191 brand names. The brand names of the permissible explosives placed on the active list are as follows:"

Oct 1, 1938

By T. L. Joseph

The size and accessibility of the Minnesota manganiferous iron ore deposits make them attractive as a potential source of ferromanganese, which is essential in the production of steel. For several years the Bureau of Mines has been conducting experiments to determine the feasibility of producing ferromanganese from these ores by a three-step process which involves (1) the smelting of the ores in the blast furnace to produce a high-phosphorus spiegel; (2) the treatment of the spiegel produced from step 1 in an electric or open-hearth furnace to separate the manganese from the phosphorus and the iron; and 3) the smelting of the high-manganese slag from step 2 to produce ferromanganese. The details of the first two steps of the process and the results of tests with the experimental furnaces have been given in previous reports.

Jan 1, 1931

By William J. Campbell

The purpose of this investigation by the Federal Bureau of Mines was to design and construct a fluorescent X-ray spectrograph for dynamic rate studies of selective oxidation in molten metals and to establish basic principles for interpretation of data obtained by this method. An X-ray spectrograph was constructed in which the sample holder is a resistance wound furnace; it was operated up to 800° C. in oxidizing atmospheres. No difficulties were experienced with the cooling or heating systems nor with the protective layer of mica around the X-ray tube window, even though the oxidizing surface of the metal is only 0.5 inch from the X-ray tube window, Means are provided for heating under controlled atmospheres for selected time? temperature cycles.

Jan 1, 1961

By Philip W. Holland

The Bureau of Mines has developed a trace helium analyzer for deter-mining helium-4 in the parts-per-billion range. The instrument is used for analyzing pure gases, laboratory-prepared standards, and atmospher-ic samples. Accuracy at the 95-pct confidence level in the 50-to 20,000-ppb range is within ±2 ppb or ±0.4 pct, whichever is greater. The minimum detectable helium-4 concentration is calculated to be 5 ppb. The analyzer consists of a modified helium leak-detector mass spec-trometer, a laboratory-built sample inlet system, and a liquid-nitrogen-cooled charcoal trap. A programmable integrator and event-control module make automatic operation possible. The portability of the analyzer allows it to be used in the field.

Jan 1, 1984

By K. D. Plants, J. H. Holden, L. F. Willmott

Pulverized high- volatile A bituminous coal was gasified with oxygen and superheated steam in a pressure - gasification pilot plant equipped for steampickup feeding . The pilot plant operated satisfactorily at relatively high steam- to - coal ratios , but steam- to - coal ratios could not be reduced much below 0.5 lb / lb without condensation of steam or softening of the coal . Carbon gasified , gas composition , and coal and oxygen requirements were essentially the same as for a pilot plant equipped with a fluidized coal feeder . Average results from the pilot plant equipped for steam- pickup feeding were coal requirement , 37.3 lb/M ( 1,000 ) scf of CO + H₂ produced ; oxygen requirement , 358 scf /M scf CO + H₂ produced ; and carbon gasified , 87.7 percent .

Jan 1, 1964

By T. A. Johnson

Recovering from low demand in 1975, raw mineral production in the United States maintained a steady climb in value and quantity throughout 1976, keeping pace with the gross national product (GNP), which increased 11.5% compared with that of 1975. The minerals industry, in the past, has met ever-increasing demand while keeping production costs to a minimum. To maintain this capability, technological research and development of more efficient processing methods must continue. The role of Government and its increasing involvement in minerals industry actions received unfavorable comment from various segments of the industry in 1976. Government pricing controls were of concern to most industrial firms marketing like products. Public land withdrawals in large blocks were of concern to the mineral industry.

Jan 1, 1978

By Carlton E. Brown

The purpose of this report is to present results of tests on the effectiveness of a spray of water mist, commonly called compressed-air water blast or water blast, in reducing the concentration of dust present in the air shortly after blasting and during mucking of the blasted material. Many observations have been male on the effectiveness of such ,sprays, but published quantitative information on comparative dust concentrations with and without their use, obtained by dust-sampling methods in use in this country, is rare if not absent. Tests conducted in South Africa about 19164/ and more recently in England5/, 6/ have shown that such sprays reduce the dust concentration to very low values within a fen minutes after blasting,

Jan 1, 1938

By D. Harrington

"While distribution of air currents to working faces is a necessity in coal mines, especially those having explosive gas, advancing faces in metal mines rarely have circulating air other than the ordinarily inadequate amount supplied through the compressed air system. Even where comparatively large quantities of air pass through main mine shafts and levels. whether the circulation is actuated by fans or by natural ventilation, only occasionally can a metal mine be found where any considerable percentage of the ""blind ends"" has circulating air of sufficient velocity to be measured by an anemometer or even be discerned by deflection of flame of candle, or of acetylene lamp; and unfortunately these ""blind ends"" include nearly all of the places from which rock is taken.During several years study of metal-mine ventilation in various mining districts of the United States, it has been found that in some mines many of the workers in ""blind ends"" practically continually breathe air with 0.02 to 0.04 per cent of CO gas from unremoved fumes from explosives; in other mines CO2 chiefly from timber decay and breathing of men, is so high that a candle will not burn though usually the acetylene lamp will, hence oxygen is below 17 per cent but above 12 per cent; in some regions CO2 from strata fills the entire mine forcing cessation of work; in other mines in dead ends, gases such as nitrogen, H2S, SO2, etc., are found under some conditions. In many regions with hot rock or water (especially in deep workings) men in blind ends must work with little or no circulation, in air above SO degrees F. and even above 90 degrees, relative humidity only too frequently being around 100 per cent; in other regions workers in blind ends in practically ""dead"" air must continually breathe enormous quantities of finely divided rock dusts. All of the above conditions are decidedly harmful to health and prevent the worker from delivering anything approaching an adequate quantity of work, and in addition, some of these conditions have direct or indirect effect in bringing about definite increase of accidents; all of the above mentioned bad conditions in ""blind ends"" in metal mines as well as their ill effects, are remediable by providing at those places adequate quantities of fresh circulating air."

Nov 1, 1923

By J. Roger Loebenstein

Demand for arsenic exceeded supply, and major domestic and foreign producers allocated available supplies to customers for the fourth consecutive year. Major demand for arsenic was about evenly divided between industrial chemicals and agricultural chemicals. Legislation and Government Programs.-Effective April 1, 1981, taxes were collected from companies producing and importing 42 chemicals and petroleum products designated as hazardous, The revenue was used to begin funding of the 5-year, $1.6 billion "superfund" being established under Public Law 96-510, the Comprehensive Environmental Response, Compensation, and Liability Act, designed to help clean up spills of hazardous substances throughout the United States. As hazardous chemicals, arsenic metal and arsenic trioxide were taxed at the rate of $4.45 and $3.41 per short ton, respectively.

Jan 1, 1982

By Ad. Breyre

For more than 20 years, Belgium, leading all the coal-mining countries, has made increasing use of sheathed explosives, which wore first suggested by the late E. Lemaire, predecessor of the author as Director of the Institut National des Mines. It appears to the author that it will be valuable to show how the use of sheathed explosives has developed in Belgium, hour the various difficulties encountered in their manufacture have been overcome gradually, and the tyres of sheathing that have survived and the reasons for their survival.

Jan 1, 1940

By James S. Browning

The Bureau of Mines conducted laboratory and small-scale continuous tests of kyanite ore from Georgia to determine the technical feasibility of recovering commercial-grade kyanite concentrates by flotation. The research indicated that combinations of sulfuric acid and petroleum sulfonate may be used effectively for flotation of kyanite from quartzite-kyanite ore. Over 87 percent of the kyanite was recovered in a concentrate analyzing 55.8 percent A1203 and 5.3 percent acid-soluble Fe203. Subsequent treatment of the flotation concentrate by high-intensity wet magnetic separation reduced the acid-soluble Fe203 to 0.8 percent and increased the alumina content to 57.6 percent, with a recovery of 82.7 percent of the total alumina in the ore.

Jan 1, 1970

By David J. Ellis

The mineral industry of Benin continued to be confined to the production of cement, crude oil, salt, and sand and gravel. Only crude oil and cement were exported, with the value of crude oil exports and cement exports constituting about 20% and 2% of export revenue, respectively. The value of crude oil exports was less than the cost of imports of refined petroleum products. Production of crude oil was unchanged from 1986, averaging 5,500 barrels per day (bbl/d). The Government managed the facilities at the Semé Oilfield while actively seeking a new manager to replace Pan Ocean Oil Co. of Switzerland, whose contract was canceled in 1986. Recoverable reserves of crude oil were estimated to be between 18 and 30 million barrels.

Jan 1, 1989

By Mary H. Brown

The heats of formation of oxalic acid and sodium, potassium oxalates, and lithium oxalates were related by solution calorimetry to the heat of formation of (COOH)2.2H20, a value believed to be reliable as reported in the literature. The following heats of formation were determined: (COOH)2(a), -198.1±0.1; (COOH)2(ß), -197.8±0.1; UAW,, -328.7±0.4; Na2C204 -316.2±0.1; K2C204, -321.9±0.2; and K2C204-H20, -393.5±0.2 kcal/mole. The heat of the crystalline transformation (COOH)2(a) ? (COOH)2(ß) was determined to be 0.30±0.02 kcal/mole at 298.15° K.

Jan 1, 1970

By S. P. Kinney, P. H. Royster, T. L. Joseph

An investigation of the production of iron in the blast furnace is obviously not an easy subject for research . Enough is known of the mechanical , thermal and chemical conditions existing inside the furnace to say certainly that they are complicated. Furnace operators have found that the process is sensitive to a number of known and to many unknown operating conditions . In order to form any conclusions of value , it seems necessary to collect a large amount of data taken with considerable care and accuracy. These facts make a blast furnace research difficult but not impossible . The most serious obstacle in attacking the problem comes from the fact that it is useless in the design and operation of the blast furnace to use the method of " trial and error , which has proved valuable in so many other industrial problems . The variables are so interrelated and are so dependent one on the other that the number of experimental combinations to be tried is enormous . There are certainly not less than twenty factors in furnace operation and design that are known to influence the results . This is apparent if it is remembered that a phrase like " size and shape of the furnace" includes height of the furnace , height , diameter and angle of the bosh , inwall batter , stockline diameter , and furnace volume ; and that a phrase like " chemical and physical properties of the fuels charged " includes size and shape of the lumps , density, porosity and strength of the coke , in addition to its chemical analysis . Let us suppose that we need choose for each of twenty factors one of two values , for example , suppose we must say only that the furnace shall be " tall " or " short , " that the bosh angle shall be " flat " OF "steep , that the ore shall be " coarse " or " fine , " or that the blast has to be "hot" or " cold , " the number of resulting combinations is more than one million . In putting twenty pennies on the table , either heads up or tails up, the number of permutations possible is the twentieth power of two , slightly more than one million. It is obvious , therefore , that some sort of mathematical relationship , a set of rules of thumb , laws , curves or the like , are needed . Whether the relationships , curves or formulas are derived from experiment , from theory, or from mere guess -work, makes no difference provided they agree with the known facts . If they do not agree with known facts , they are worthless no matter what their origin or how weighty the " authority" vouching for them. Few such relationships have appeared in blast- furnace literature , and it may be doubted whether such formulas can be discovered .

Sep 1, 1923

By F. S. Crawford

Safety devices and guards are often looked upon as the last word in safety by the men around the shop or large industrial plant . However , thorough knowledge of the details of their jobs and of the dangers attending them are even more important . It should be unnecessary for all men to go through the experience of the first man to meet an unknown danger , but that appears to be about the only way by which many learn . Practically every danger connected with the job around a mine , blast furnace , steel mill , foundry , coke oven , cement mill , or other operation , was encountered for the first time by someone , and if he was fairly fortunate he either got hurt or just missed being injured and lived to tell his " budaies " how it happened; he spread the knowledge of that particular danger . Sometimes , but not often , a man can foresee a danger . If he could always be on guard and remember everything he had ever learned and also know everything that had happened to the other fellow , and then let that knowledge keep him aware of the dangers in his own immediate " job , " so that he would work the safe way for both himself and the other fellow , he would have what safety engineers call " safety consciousness . " Being safety conscious is a fine attribute , as it really means knowing all about one's job . A man who is really safety conscious is one of the best and most efficient workmen in the whole plant . The boss wants men of that kindmen who want to learn and who try to learn every little detail about their jobwhere there is danger of spoiling the heat or getting burned by hot metal in a steel plant or of loading rock instead of coal or ore in a mine . Such men know how to do whatever job they are on easily and with the least amount of hard work and at the same time get it done as quickly as possible with safety . A man who is safety conscious has to nearly all intents and purposes developed eyes in the back of his head , if he is in a big mill where there if something going on all around him . These eyes are not real eyes , but they are what might be termed a sixth sense which he has developed by his experience in the mill as well as in other dangerous work which he may have done before in other plants . There may be occasions when a man's safety consciousness will leave him for just a short time ; this is likely to happen when he is thinking about a quarrel he had with his wife which has not been cleared up happily , or perhaps when he has bought too many things on installment and with sickness at home

Apr 1, 1931

By Kevin Ashley

Because toxicities may differ for Cr(VI) compounds of varying solubility, some countries and organizations have promulgated different occupational exposure limits (OELs) for soluble and insoluble hexavalent chromium (Cr(VI)) compounds, and analytical methods are needed to determine these species in workplace air samples. To address this need, international standard methods ASTM D6832 and ISO 16740 have been published that describe sequential extraction techniques for soluble and insoluble Cr(VI) in samples collected from occupational settings. However, no published performance data were previously available for these Cr(VI) sequential extraction procedures. In this work, the sequential extraction methods outlined in the relevant international standards were investigated. The procedures tested involved the use of either deionized water or an ammonium sulfate/ ammonium hydroxide buffer solution to target soluble Cr(VI) species. This was followed by extraction in a sodium carbonate/sodium hydroxide buffer solution to dissolve insoluble Cr(VI) compounds. Three-step sequential extraction with (1) water, (2) sulfate buffer and (3) carbonate buffer was also investigated. Sequential extractions were carried out on spiked samples of soluble, sparingly soluble and insoluble Cr(VI) compounds, and analyses were then generally carried out by using the diphenylcarbazide method. Similar experiments were performed on paint pigment samples and on airborne particulate ?lter samples collected from stainless steel welding. Potential interferences from soluble and insoluble Cr(III) compounds, as well as from Fe(II), were investigated. Interferences from Cr(III) species were generally absent, while the presence of Fe(II) resulted in low Cr(VI) recoveries. Two-step sequential extraction of spiked samples with (?rst) either water or sulfate buffer, and then carbonate buffer, yielded quantitative recoveries of soluble Cr(VI) and insoluble Cr(VI), respectively. Three-step sequential extraction gave excessively high recoveries of soluble Cr(VI), low recoveries of sparingly soluble Cr(VI), and quantitative recoveries of insoluble Cr(VI). Experiments on paint pigment samples using two-step extraction with water and carbonate buffer yielded varying percentages of relative fractions of soluble and insoluble Cr(VI). Sequential extractions of stainless steel welding fume air ?lter samples demonstrated the predominance of soluble Cr(VI) compounds in such samples. The performance data obtained in this work support the Cr(VI) sequential extraction procedures described in the international standards.

Jan 1, 2009

By David Hoadley, Kenneth R. Maser, Ashok B. Boghani, James E. Billar, D. Randolph Berry, Mackenzie Burnett, Robert H. Trent

C.5 Safety Equipment and Control Devices Safety equipment and control devices serve two principal functions in mine escape hoists. First, they can be used to provide important safety features such as protection against overspeed, over¬travel and undertravel. Second they can be used to automate or partially automate the operation of the escape hoist. Typical equipment available is described in the following section. 1. Simplex and Lilly Hoist Controllers Manufacturers: Logan Actuator Co. 4956 No. Elston Ave. Chicago, Illinois 60630 312-736-7500 The Simplex and Lilly Controllers provide a means for electrically shutting off the power to the hoist and the energy to physically set the brakes in the event of overspeed, overtravel, undertravel and failure to begin deceleration within sufficient distance

Jan 1, 1976

By C. W. Smith

The Bureau of Mines conducted laboratory beneficiation tests on four samples of waste. granite sludge to devise a method of recovering silicon carbide (SiC). Froth flotation using creosote as a collector in an alkaline circuit resulted in concentrates containing over 91 pct SiC from each of the samples. Recoveries ranged from 43.1 to 86.6 pct. Single-stage flotation of sample A using a column flotation cell produced a concentrate containing 92.0 pct SiC with a recovery of 71.4 pct. Flotation using petroleum sulfonate as a collector in an acid circuit resulted in a concentrate containing 95 pct SiC from one of the waste granite products with a recovery of 97.5 pct .?

Jan 1, 1987

By Brian R. Zelenka

The Bureau of Mines (Bureau) reviewed all available information regarding geologic and depositional processes contributing to potential coastal and offshore platinum group metal (PGM) placer deposits around the Goodnews Bay Mining District. The Bureau found that favorable environments for PGM along with gold and chromite enrichment include: (1) buried paleofluvial channels; (2) recent paleofluvial channels with little marine sediment overburden, (3) beach deposits, particularly in the upper swash zone and near back beach environments; (4) paleostrand lines; (5) shoal lag deposits inside the mouths of Goodnews and Chagvan bays; and (6) bases of far offshore tidal ridges which may represent reworked glacial deposits. Limited geologic and compositional (assay) data prevent determination of deposit size and grade of PGM mineralization for each deposit class. Future geologic sampling requirements for demonstration of identifiable offshore and beach PGM-bearing placers are discussed. Beach and offshore sampling programs conducted by the Bureau in 1986 will contribute additional information providing verification of specific deposit classes.

Jan 1, 2011

By J. H. East

Potash is one of the essential chemicals used in fertilizing soil deficient in natural minerals . Europe uses a large tonnage of potash in the form of easily soluble salts , and this is particularly true of those countries where the natural minerals in the soil have been exhausted owing to intensive cropping of the land . The application of potash to the soil in these countries is essential if normal crops are to be obtained ; during the war , some European countries were unable to obtain sufficient potash , and productivity of the farming areas declined seriously . • The largest -known deposits of potash in the world ; with the possible. exception of Russia , occur in Germany , and the German output of processed salts constituted about 65 percent of world production prior to the war . The German potash-plant installations are large , modern , brick and steel construction and apparently built for a planned operation of many years . Two districts produced approximately 80 percent of the German potash; the Werra -Fulda district , near Vacha , had the largest production , and the Sudharz district , near Nordhausen and Sonderhausen , was second . (Fig . 1. ) Hannover and Stassfurt were two smaller producers . Potash fertilizers are rated in terms of potassium oxide (K20 ) . The usual basis for calculation of production or application of the salt is to reduce the potash content to 40 percent K₂0 .

May 1, 1947