Search Documents

By John Hays Hammond, James Douglas, J. PARKE CHAN- NING, W. R. Ingalls, J. R. Finlay

The committee making this report, consisting of Walter Renton Ingalls (chairman), J. Parke Channing, James Douglas, James R. Finlay, and John Hays Hammond, was originally appointed at a meeting of the American Mining Congress at Denver, Colo., in No- vember, 1906. The object of this appointment was the drafting of a modern law governing quarrying and metalliferous mining which could be recommended to the several States for adoption, in the hope that the passage of such a uniform law by the mining States would tend to lower the number of fatal and serious accidents. The first step of the committee (the personnel of which has re- mained unchanged from the beginning) was to procure copies of existing laws from the officials of the several States of the Union. With the assistance of the Engineering and Mining Journal, copies of the laws of Great Britain, the Transvaal, New South Wales, Victoria, Queensland, Western Australia, Tasmania, New Zealand, and certain European countries were also obtained. The replies to the inquiries made at that time developed the fact that a number of States in which mining was carried on had no laws at all. Other States were found to have elaborate provisions regulating coal min- ing, but none applying to metalliferous mining. Still other States were found to have miscellaneous and unrelated provisions passed at odd times, seemingly as the result of the occurrence of some dis- aster or other.

Jan 1, 1915

By I. F. Avery

The productive capacity of natural gasoline and cycling plants in the United States on January 1, 1956, was 46.4 million gallons per day, according to the Bureau of Mines r biennial survey. This represented an increase of 7.5 million gallons per day during the 2-year period since the last survey. In the previous 2-year period, capacity had increased 4.8 million gallons per day. The total number of plants increased from 535 on January 1, 1954, to 600 on January 1, 1956. The number of operating plants increased from 521 to 571. The major increases in capacity took place in Texas, Louisiana, New Mexico, and Oklahoma, with the absorption-type plants continuing to account for most of the new construction. All types of plants showed construction gains with the exception of charcoal which showed no change.

Jan 1, 1957

Design a new acoustic monitoring system to more accurately forecast impending rock bursts, and to assist in understanding the rock burst phenomenon. Background Rock bursts arc the major cause of injuries and deaths in deep underground mines in the Silver District near Wallace, ID. Bureau investigations of the rock burst phenomenon resulted in significant improvements in computerized acoustic technology, and achieved limited success in forecasting several large events. Research demonstrated that the location of rock noise, and the rate at which these events occur, are indicators of areas that could fail violently. In minewide monitoring, the typical array of acoustic sensors (geophones) is arranged to cover an entire mine with 16 to 32 separate instruments. The mines intended to be covered may be 7,000 feet in depth and up to several miles in extent. While such an arrangement is capable of detecting and locating large seismic events (rock slippage along natural fractures or faults), the geophones are too far apart to accurately locate mining-induced events at the active workplaces. The Bureau devised a strategy to concentrate the geophones into typical slopes (mining areas about 200 by 500 feet) to record the rock noise in areas where the miners work. By using such a dense geophone array at a mine, the Bureau provided event location and rate information to mine operators who removed workers and ceased production from active mine areas that subsequently suffered rock bursts.

Jan 1, 1989

By J. J. Demeter

A tube-wall reactor with a Raney nickel catalyst deposited on the outer wall of the tube by flame spraying is effective in the practically complete conversion of 3H2+1CO synthesis gas to a high-Btu gas (methane) at an hourly space velocity of 7,000 volumes of gas (NTP) per hour per volume of annular volume. Partially reacted synthesis gas containing an appreciable amount of methane can also be treated in this reactor to increase the heating value to over 900 Btu per cubic foot. Excellent heat removal through the metal wall to a coolant and temperature control were obtained. The heat transfer co-efficient from the catalyst to the coolant was about 275 Btu per hour per square foot per ° F. Synthesis tests were conducted with tubes 1.2 inches in ad by 6 inches long, and 1.3 inches in od by 36 inches long. When operating at a synthesis gas rate of 100 to 120 scfh per square foot of catalyst-coated tube, catalyst life was long enough to realize a catalyst cost for the raw Raney nickel alloy of about 0.3 cent per 1,000 cubic feet of pipeline gas (900 to 950 Btu per scf). Gas recycling at ratios of 1:1 to 3:1 was effective in increasing conversion and in extending the life of the catalyst to about 16 weeks. In cost and in operating characteristics the tube-wall reactor compares favorably with the fluidized-bed and hot-gas-recycle reactor systems for the synthesis of high-Btu gas from H2+CO.

Jan 1, 1967

By R. F. Abernethy

A chemical method of determining microgram quantities of arsenic in coal was investigated by the Bureau of Mines to supplement a semiquantitative spectrographic method of determining arsenic in coal ash. In accordance with a method recommended by the International Organization for Standardization, 1-gram samples of coal are decomposed by wet oxidation with boiling sulfuric acid (H2S04) and nitric acid (HN03) to remove the organic matter. After heating to fumes of SO3 to remove HN03, the arsenic is separated as arsine by the action of zinc in H2S04 solution. The arsine is absorbed in dilute iodine solution in which the arsenic is determined colorimetrically by the molybdenum-blue reaction. Two modifications of the method for obtaining the arsenic in solution, in addition to the wet oxidation method, give satisfactory results. The modifications are (1) furnace ashing with MgO added to the coal, followed by treatment with H2S04, and (2) extraction of arsenic from the coal by dilute HNO3 without ashing. Float-and sink-tests show that arsenic is associated mainly with mineral matter in the three coals examined. High-temperature ashing tests show that very little arsenic is volatilized from coal ash below 1,000° C, but it is virtually all removed from the ash at 1,300° C.

Jan 1, 1968

By Louis A. Turnbull, JOSEPH J. SHIELDS

The Bell & Zoller Coal & Mining Co. recently completed construction of two slopes at Mine 3 near Zeigler , Ill . The slopes are in the Big Muddy River Valley , and construction was particularly difficult because the strata from the surface to a depth of 70 feet comprise water saturated sandy clay and sand . Many mining companies have similar shaft- and slope - sinking problems , and because these slopes were satisfactorily completed and now are in use the methods followed during construction are described in this information circular . It is believed that other companies with similar problems . will benefit by adopting the methods followed at Mine 3 .

Apr 1, 1949

By A. B. Hooker

Since man first mined underground, there has been need for adequate illumination; this need has never been fully supplied. At first, suitable lamps were not available. Gradually they have been developed, but along with that development the need for better and better lamps has continued owing to the following conditions and factors: 1. Increasing hazards from gas and dust ignitions. 2. The speeding of operations with mechanized mining, which necessitates greater visibility. 3. A demand that cleaner coal be loaded, which requires higher levels of illumination. 4. The cost of compensation for injuries that has created a demand for better illumination and safer lamps. Use of better lamps has been retarded by: 1. Prejudice and resistance to change on the part of the workers in some districts. 2. The cost and upkeep of the lamps. 3. The present types of lamps, while a great improvement over the old lamps, do not entirely fulfill the requirements for a safe and efficient light for underground workers.

Jan 1, 1938

By Maria I. De Rosa

Table 1 and figure 1 show the number of fires and fire in¬juries that occurred in underground coal mines by state during 1990-1999. Table 1 also shows by state the risk rates, employ¬ees' working hours, lost workdays, and coal production. Over¬all, 87 fires occurred in 12 states. Twenty-seven of those fires caused 34 injuries (the yearly average was 8.7 fires and 3.4 injuries). One fire and one injury involved a contractor. The underground mine fires required 25 mine rescue team interventions and 30 mine/section evacuations followed by 13 mine/section sealing/flooding/CO2/N2, gas injections. The Ewhr value was 1,003 x 106 hr (In = 0.007), the CP value was 4,008 x 106 st (Frr = 0.022), and the LWD value was 208. Virginia had the most fires (15 fires and 7 injuries). Pennsyl¬vania had the most fire injuries (12 fires and 9 injuries), fol¬lowed by Kentucky (12 fires and 6 injuries), and Alabama (12 fires and 4 injuries). Among these states, Alabama had the highest fire risk rate value (Frr = 0.073), whereas Pennsylvania had the highest injury risk rate value (In = 0.016). Table 2, partly illustrated in figure 2, shows by time period the number of fires, fire injuries, risk rates, employees' working hours, lost workdays, and coal production. The number of fires and fire injuries show a decrease followed by an increase during the five time periods (see table 2 and figure 2). This was ac¬companied by a decline in employees' working hours throughout the periods and an overall small decrease in coal production. The In and Frr values follow patterns similar to those shown by the fire and injury values. By comparison, data from Pomroy and Carigiet [1995] show that during 1978-1992 a total of 11 states were involved in 164 underground coal mine fires (yearly average, 10.8) with 43 injuries (yearly average, 2.9) and 27 fatalities (yearly average, 2; however, the 27 deaths occurred during a single fire caused by an overheated air compressor [MSHA 1984]). The CP value was 5,340 x 106 st (yearly average, 356 x 106 st) (Fn = 0.031). Data on employees' working hours and injury risk rates were not available. Tables 3-8 show the number of fires by ignition source, method of detection and suppression, equipment involved, location, and burning material by time period. Figure 3 shows the major variables during 1990-1999. Table 9 shows the number of fire injuries per number of fires causing injuries and total fires by year, ignition source, equipment involved, and location.

Jan 1, 2004

By Harold J. Bennett

This report deals with the processing and marketing of iron and steal scrap in the intermountain States of Arizona, Colorado, New Mexico, Utah, and Wyoming and the northwestern Plains States of Nebraska, North Dakota, and South Dakota. The quantity and quality of iron and steel scrap consumed in both the steel mills and iron foundries in these States in 1964 were decided by (1) the type of facilities used to produce an end product; (2) the availability of a dependable source of iron and steel scrap at competitive prices; and (3) the, ratio of the cost of iron in iron ore to iron in scrap. In recent years the quantity of scrap used per ton of steel ingot produced has decreased. The major individual. consumers of iron and steel scrap were the steel mills in Arizona, Colorado, and Utah, foundries in Utah and Arizona, and copper leaching, operations in Arizona, New Mexico, and Utah. About 2 million tons of iron and steel scrap was used by the iron and steel industry in 1964. Although there has been a decline in the amount of scrap used per ton of steel ingot produced because of changes in steelmaking methods, there has been a slight increase in the overall quantity of scrap used because of the increase in ingot production. It is estimated that the scrap consumption in the steel industry will increase by 19 percent by 1980. In addition to the scrap consumed by the steel industry, 273,000 tons of ferrous scrap were used by copper-leaching operations. Thirty-one percent of the ferrous scrap used by the steel industry in 1964 was purchased from dealers and other sources. The CF&I Steel Corp. (formerly The Colorado Fuel and Iron Corp.) at Pueblo, Colo., complemented its blast- and open-hearth-furnace operations with basic-oxygen converters in 1962. The basic-oxygen and open-hearth furnaces were charged with 30 and 90 percent scrap, respectively. Future use of the open-hearths would probably be used to supplement ingot production requirements. Because it was more economical to use less scrap and a high molten-metal charge, the United States Steel Corp. at Geneva, Utah, which uses the open-hearth process to make steel, charges the furnaces with 25 to 35 percent scrap. The Allison Steel Manufacturing Co. at Tempe, Ariz., uses a 100 percent scrap charge in its electric furnace. Although it was estimated that there were 327,000 tons of various grades of motor vehicle scrap generated in 1963, no estimates were made concerning the total quantity and grade of scrap available in the area. Most of the scrap used in the steelmaking industry originated within the area. It was advantageous to sell scrap generated in eastern Nebraska, North Dakota, and South Dakota to markets in the Midwest because of freight costs.

Jan 1, 1967

By H. E. Camargo

In an effort to decrease noise-induced hearing loss (NIHL) in coal preparation plant employees, the National Institute for Occupational Safety and Health (NIOSH) is conduct­ing research to identify and control dominant noise sources in vibrating screen (VS) machines. To this end, acoustic measurements of the noise radiated by a dewatering VS were conducted at the Pittsburgh Research Laboratory (PRL) using microphone phased-array technology. These measurements allowed for the identification of the screen as the dominant source in the 250 Hz 1/3-octave band. The sidewalls are the major contributors in the 315 and 400 Hz bands, whereas the eccentric mechanisms and the electric motor are the dominant sources in the 800 and 1,000 Hz bands, respectively.

Jan 1, 2009

By R. P. Beyer

As part of its thermodynamic investigations of mineral compounds, the Bureau of Mines has written an algorithm based on Newton's method for solving for the characteristic Debye temperature of a compound, from heat capacity and temperature data. A listing of a FORTRAN IV program based on this algorithm, for calculating Debye temperatures given heat capacities or for calculating heat capacities given Debye temperatures, is available from the author upon request.

Jan 1, 1981

Improve the dust control effectiveness of dry collection systems on surface coal mine drills. Approach Use a dust pelletizer to convert the respirable dust particles discharged by the dry collector into dust pellets that present no health hazard. Background Blasthole drills are well-known sources of respirable dust that can contain significant amounts of quartz. The drills frequently use a dry cyclone-filter type collector that can obtain dust reductions theoretically greater than 95 pct. However, surface mine drills using dry collectors typically have three major dust sources that significantly reduce the overall effectiveness of the collection system: (1) the dust collector dump cycle, (2) drill shroud leakage, and (3) leakage around the drill stem seal in the drill table.

Jan 1, 1989

By Oliver Bowles

"A New Mica Company in China A report has been received from the American Consulate at Chungking, China, to the affect that a new company has been organized to operate a mica mine north of Ta-chien-lu, in the province of Ssu-Chuan. The company, which is entirely under Chinese management and control, has a working capital of $10,000. While comparatively new, the mine has been worked before, and apparently with some success. The mica is said to be of good quality. It is claimed that the deposit will supply a limited amount of mica that will cut in pieces a foot square or over, and larger quantities of smaller sizes. The chief difficulty is transportation, for it is reported that a ten days' journey, part of it over mountain trails, will be necessary to transport the mica from the mine to Yachow, the nearest practical waterway. It is probable, therefore, that the output of the mine will be limited.Necessity for Careful Trimming and Grading of MicaA recent report to the Department of Trade and Commerce, Ottawa, Canada, by Acting Trade Commissioner C. G. Venus, London, England, contains information which is of vital interest to mica producers in the United States. It is pointed out that mica exports from Canada to England show a gradual decline dur¬ing recent years, the figures being as follows: 1913- 1,383 cwt: 1914 - 1,225 cwt: 1915 - 1,864 cwt: 1S16 - 879 cwt: 1917 444 cwt: 1918 - 480 cwt. Shipments from India to England, on the other hand, show a steady increase from 40,178 cwt. in 1913 to 66,401 cwt, in 1918."

Jan 1, 1920

By Joseph W. Town

The Bureau of Mines conducted studies related to SO2 air pollution to determine attritioning rates, SO2 sorption rates, and sulfur loads that could be obtained on commercial alkalized alumina sorbent pellets. Fluidized-bed attritioning rates ranged from 0.025 pct/hr for alkalized alumina with a crushing strength of 4 kg to 0.075 pct/hr for 0.5 kg crushing strength mate¬rial. Airlift attritioning rates ranged from 0.50 pct/hr for 3 kg crushing strength alkalized alumina to about 3 pct/hr for 0.5 kg material. Attritioning rates for the commercial alkalized alumina were comparable to those obtained for sorbent pellets prepared in the Bureau of Mines laboratory. Sorption rates were related to S02 concentration in flue gas, temperature, and presence of nitrogen oxides in the gas stream. Sorption rates at 300° C were 0.35 X 10-6 gS/gp/sec (grams sulfur per gram pellet per second) in 0.045 pct so, gas, 5.1 x 10-5 gS/gp/sec in 0.34 pct SO2 gas, and 65 X 10-5 gS/gp/sec in 10 pct SO2 gas. For the 0.34 pct S02 gas, sulfur loads of 0.10 gS/gp (the projected load for regeneration) were obtained in 47 min at 130° C and in 116 min at 300° C. The presence of either NO or NO2 in the 0.34 pet S02 gas increased the SO2 sorption rates 2 to 3 times at 300° C, but had no effect at 130° C.

Jan 1, 1969

Develop a method of dewatering ultrafine mineral waste that will increase water recovery from the waste and produce a dewatered material that eliminates the need for large settling ponds. Background In the hydrometallurgical treatment of many ores and concentrates to recover mineral values, slurries of fine particles are generated. Some of these slurries settle slowly and are difficult to dewater. This inherent property causes environmental and handling problems for the minerals industry. Examples of such problem wastes are clay wastes generated during the mining and beneficiation of phosphate ores, the processing of coal to produce a low-ash material, the cleaning of bentonite, beneficiation of potash, and the recovery of mica from clay-containing ores. At the present time these waste slurries are treated by techniques such as impoundment, thickening, and thickening followed by filtration. But factors such as new environmental regulations, the loss of mineral values in the waste slurries, the need to recycle water in the processing facility, and the lack of land suitable for impounding the waste have shown that new technology will be needed in the future to handle waste slurries.

Jan 1, 1986

By C. L. Severy

On the Pacific coast during World War II, a tremendous ship-building industry was developed, Early in the war it became impossible to obtain in- got or steel scrap for ship ballast. Magnetite, an oxide of iron, was sub- stituted as it fulfilled the requirements of weight for available space in the ships. Consequently, a new use for the western magnetite was rapidly developed.

Jan 1, 1948

A primary objective of the Surface Mining Control and Reclamation Act is to establish uniform national regulatory standards to protect the environment during mining and for reclaiming land after it is disturbed by current and future surface coal mining. In recognition of the wide range of climatic and geologic conditions in coal-producing areas, Congress provided that individual states may establish their own programs for regulating surface and underground coal mining and reclamation on private land. The standards for state programs must be at least as effective as the federal standards. Initial and Permanent Regulatory Programs Congress recognized the importance of establishing regulations to implement the Act as quickly as possible, while recognizing that the preparation of such complex regulations would be a lengthy process. Consequently, a two-phase schedule was established. An abbreviated initial program was put in place immediately, followed by a more extensive and detailed permanent regulatory program. The initial program regulations were published in December 1977, and mine permits issued by states after February 1978 were required to conform with those regulations. Regulatory provisions contained in the initial program included 12 basic performance standards, continuation of existing state permitting, bonding, and enforcement processes (although if those features did not already exist, they did not have to be added), a federal inspection frequency of once every six months, joint state and federal inspection and enforcement in states that had existing programs, and the prohibition of mining in the specific areas listed in the Act. Permanent program regulations were published in March 1979, following extensive review and comment from the public, including the coal industry and organized environmental groups. The regula¬tory provisions in the permanent program expanded those in the interim program by including the implementation of all performance standards contained in SMCRA, a new permitting process, a requirement for performance bonds, an increased inspection frequency (one per month), a new enforcement process, and a process for designating lands unsuitable for surface mining. The regulations for the permanent program have been revised several times since 1979; more revisions can be made as new mining and reclamation tech¬niques are developed. Such changes were anticipated by Congress; in fact, a provision in SMCRA for experimental practices encourages advances in mining and reclamation techniques.

Jan 1, 1992

By A. A. Berk

In the course of a study of the formation of external deposits on tubes in water-tube boilers it became desirable to determine the sulfur dioxide (SO2) and sulfur trioxide (SO3) in the Due gases. Determinations made by the A.S.M.E. method for SO2 and SO3 in gaseous products of combustion did not give accurate results. It was found that minute quantities of copper, present in the flue gases from the coal in use, caused oxidation of sulfite in the absorption bottle and that the carbon dioxide (CO2) in the flue gases caused high values for SO2. The A.S.M.E. test procedure was revised to prevent oxidation of sulfite in the absorption bottle and to allow for the effect of CO2; subsequent analyses of flue gases produced reliable results. The revised procedure is described.

Jan 1, 1950

By Byron. O. Pickard

"An Arizona mining company recently demonstrated a new use for the geophone by successfully locating leaks in compressed-air lines which were buried under from 1-1/2 to 2-1/2 feet of fine rock fill. The following information is abstracted from data sent to the Bureau of Mines by the superintendent of the mine.The company has two parallel main compressed-air lines, about one and one-half miles long, buried under an average of two feet of fine rock fill. One of the lines is a four-inch high-pressure (1000 pounds) main, and the other line a ten-inch low pressure (90 pounds) main. The two mains are separated by a 10 to 3C foot interval, and run from the compressor plant to the No. 2 shaft, where they are taken underground. A pump line is also buried in the immediate vicinity.Several leaks, not audible enough to be located, were developed in the Alms. Various =Abode were suggested that did not seem practicable to the management. Finally, the company obtained a Bureau of Mines' geophone and experimented with it. The first test& were conducted while the pumps were running, and while there was noise on the concrete pavement, all of Which caused so much vibration in the geophone that it was impossible to detect the leaks.The second attempt was made at the close of the day shift when the compressors were not operating and when the pumps could be shut down. The valves in the far end of the surface lines were closed, and the lines were pumped to full pressure (90 and 1,000 pounds respectively).Geophone readings were then taken at 7 or 8 foot intervals directly see the lines. Several leaks some very large in the high-pressure line were audible with the geophone at distances varying from 15 to 30 feet. A con-le leak in the low-pressure line was found at a distance of 10 feet. detecting the leaks, no difficulty was found in locating them exactly. ""At this time"", laid the superintendent of the mine, are unable to large a leak must be in order to be located under two feet of loose geophone. The fill we worked over was quite loose and dry and unfavorable for the work in question. However, we have no that the instrument is a valuable adjunct to our business""."

Aug 1, 1922

By R. V. Lundquist

The work described in this report, part of the Bureau of Mines long-range program to develop methods of utilizing submarginal domestic sources of aluminum, was undertaken to investigate the effects of iron in the lime soda sinter process, The approximate Fe2O3 content in a sinter for maximum alumina and soda recovery was 8 to 9 percent. Fe2O3 appears to inhibit gelation, and 15.5 percent Fe2O3 produces effects similar to those produced by 1 percent sucrose. In the lime soda sinter process, aluminum silicates are sintered with limestone and soda ash to yield dicalcium silicate and sodium aluminate. The sodium aluminate is extracted by leaching in caustic solution. The solution is purified by heating in an autoclave with lime to remove silica, and alumina trihydrate is precipitated with carbon dioxide. The reactions involved in sintering and leaching are complex. A number of studies by the Bureau of Mines4-9 and others1 indicate that the iron content of sinters influenced the recovery of alumina and soda and the gelation characteristics.

Jan 1, 1962