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By Joseph V. Mather, E. H. McCleary

"INTRODUCTION Workmen are transported in shafts in various types of cages or skips, most of which were designed primarily for hoisting cars and materials. Therefore, in general the cages or skips are not completely enclosed, adequate and gates are not always provided, and at many mines signaling devices and telephones are re¬stricted to those at the various landings in the shafts.Shaft accidents are usually severe - frequently fatal - and as a rule such an accident is caused by failure to comply with company rules or by ignoring them.Sixty men were killed and 555 men were injured in shafts of the anthracite and bituminous coal mines of the United States during the 5-year period 1938-42. 4/ Many of these accidents could have been prevented by having properly enclosed cages and adequate locking devices on doors to prevent workmen from falling into the shafts.The officials of the Heidelberg Coal Co. contemplated utilizing an old coal-hoisting shaft as a man-hoisting shaft; however, it was their desire to avoid the use of the conventional cage and to try to provide a safer means of transporting men in the shaft. Investigations and studies made by the officials revealed that an elevator similar to those used in large buildings would be more economical in first cost, maintenance, and operating costs would be less, and it would be safer and more convenient for the workmen. Effective safety devices for such elevators have been developed to such a high degree that those properly installed seldom fail. The elevator or man cage finally chosen cannot be pulled above the top landing through mechanical or man failure; it stops automatically at each landing and cannot be moved while a door is open; when the cage leaves the landing the doors opening to the shaft are automatically locked by mechanical and electrically operated locks; electric lights, telephone communication, and push-bottom controls are available on the cage, and adequate safety switches and overspeed controls are provided."

Jun 1, 1947

By Walter W. Fisher

A kinetic investigation of copper cementation in a revolving drum was undertaken by the Bureau of Mines to explore the effects of a porous copper deposit attached to the iron surface and a fluidized slurry of copper particles surrounding the iron precipitant. The rate of cementation was found to be significantly enhanced by the increased cathodic areas provided by a porous copper deposit or the presence of a fluidized bed of copper particles contacting the iron precipitant. The cementation rate was found to be retarded by increased ionic strength, low pH, and the presence of oxygen. The cementation reaction was first order with respect to precipitant surface area. Copper cementation on iron is visualized to occur by two basic mechanisms. Precipitation may occur through a series of shorted electrochemical cells, whereby cupric ion precipitates on a growing cathodic copper deposit, or, deposition may occur via a fluidized cathode of copper particles contacting the ion precipitant.

Jan 1, 1976

By B. I. Ferber

Toxic and explosive atmospheres are discussed, along with some of the instruments commercially available for their detection. No attempt has been made to evaluate the accuracy of anyone device. This circular has been prepared primarily to aid mine inspectors in selecting suitable instruments for underground gas detection.

Jan 1, 1972

By O. C. Blade

A summary of the characteristics of motor gasoline for the summer 1951 is presented in table 1, and for comparison, a similar summary for the summer 1950 is shown in table 2. Trends of some of the more important characteristics over a period of years are shown in figures 1 and 2. As indicated, octane numbers of motor gasolines sold in the United states decreased approximately one-half to one octane unit from the record levels attained during the winter of 1950-51 and are a little below the octane numbers of summer 1950. However, average vapor pressures of the summer gasolines did not change, and certain distillation temperatures varied only slightly from those of the year before.

Jan 1, 1952

By M. N. Rubin

This report summarizes the work performed under USBM contract J0100018. The purpose of this work was to document the currently available noise control techniques that can be incorporated into new coal preparation plants during the design stage. This was accomplished by reviewing the related experience of the contractor and subcontractor (Bolt Beranek and Newman Inc.), conducting an extensive literature search, visiting operating coal preparation plants, and contacting various equipment manufacturers. The treatments addressed include equipment substitution, changes in plant layout, and retrofit treatments for existing equipment.

Jan 1, 1982

By G. R. Hopkins, E. W. COCHRANE

The number of completed petroleum refineries in the United States continued to decline in 1937 , but the total capacity to process crude oil continued to increase . These facts were ascertained in the Bureau's annual canvass of refinery capacity as of January 1 , 1938 . Several important changes were made in the census questionnaire for January 1 , 1938 . First , the basis of reckoning cracking capacity was changed from cracking stock charged to cracked gasoline produced . Although this is a definite improvement , in that it is no longer necessary to consider the yield , it is unfortunate that the data for January 1 , 1938 cannot be compared with cracking - capacity statistics since 1925. Other changes or additions included separating capacity at operating plants into that actually operating and that closed down ; collecting data on capacity added or retired during the previous year ; breaking down idle capacity according to physical status ; and separating new capacity into that built for replacement and that built to augment existing capacity . Prior to January 1 , 1938 , the total capacity of an operating plant was listed as " operating " even though some stills might have been closed down ; furthermore , the only capacity reported as being under construction was that of new plants that were being built on January 1. To make the statistics clear , the totals for the United States as of January 1 , 1938 , are given on both the old and the new bases . On January 1 , 1938 , there were 551 completed plants compared with 572 the previous year . Ten new plants were under construction on that date compared with 11 the year before . The greatest number of completed plants recorded was 632 on January 1 , 1936 ; since then , competitive conditions , particularly in the East Texas field , have been instrumental in reducing the number of small independent plants . The total crude- oil capacity of the completed refineries on January 1 , 1938 , was 4,351,151 barrels , of which 3,970 , 196 barrels ( 91 percent ) represented the capacity in actual operation and 380,955 barrels ( 9 percent ) was shut down . The " shut -down " capacity ( 199,875 barrels on the old basis ) was the lowest since pre- depression days , chiefly because numerous idle East Texas plants were removed from the list . The new method of compiling the statistics sheds considerable light on excess crudeoil capacity , which has been the subject of considerable speculation in recent years . The highest daily average crude runs to stills reached in this country was about 3,460,000 barrels in September 1937. At that time , the total crude - oil capacity was about 3,925,000 barrels . This indicates that at peak operation the excess capacity was somewhat less than

Aug 1, 1938

By R. S. Dean

[Methods s of preparing the manganese metal that has been used in chemical and metallurgical investigations have passed through a cycle. Most of the investigations made before the turn of the century, used Moissen's pyrophoric manganese.3/ This material was made by electrolysis into a mercury cathode and distillation in vacuo. The material was essentially pure, and investigations in which it was employed (with proper precautions against oxidation) led to accurate results on tie intrinsic behavior of metallic manganese.]

Jan 1, 1941

By John J. Henn

An economic evaluation was made of the Bureau of Mines incinerator residue separation process to update the one published in 1971 to a mid-1.974 cost basis. This evaluation includes a modification of the glass-recovery operation used In the original plant design as well as a unit to bale the ferrous scrap product before shipment. Products from the plant are ferrous metal, aluminum and copper-zinc scrap, and a mixed-color glass cullet. The estimated capital and operating costs for four plant sizes are as follows : [ ] The operating costs do not include credits for recovered metals and glass.

Jan 1, 1975

By P. A. Hendricks

This U.S. Bureau of Mines (USBM) report identifies and evaluates factors responsible for metal/nonmetal (M/NM) underground mining accidents involving mobile equipment. Information regarding the occurrence and severity of the accidents, the type of equipment involved, the primary and contributing causes, and preventive measures is included. The goal of this report is to provide information that will aid mine operators and safety managers in the recognition of hazards associated with operating mobile mining equipment in an underground mining environment.

Jan 1, 1994

By S. M. Shelton, W. A. Calhoun, M. M. Fine, T. L. Johnston

"This report is () expansive test program by the Bureau of Mines to determine methods from various and ferrous manganese-grade product () widespread () and manfniferrous iron ores. Among the samples received for testing was one from the pits of the Barytes Mining Co., 1-1/ 2 miles northeast of Cartersville, Ga.. The property is approximately in the center of the Cartersville manganese district and shares a common corner with properties of the New Riverside Ochre Co. and the Etowah Development Co., both producers of manganifereus ores. The deposit is typical of the district and occurs in residual clays resulting from weathering of the Shady limestone and Weisner quartzite. 7/The property is developed by a number of open pits ranging to 60 feet in depth. In 1918 several carloads of manganiferous iron ore was mined from an alit on the property. Since then mining operations have been negligible. The ore is known locally as calico ore.A 4-ton sample representing -re as it occurs in the -pen pits vas furnished for testing. The sample consisted of a mixture of red iron oxides, wad, and clay, with small pebbles of manganese oxides and siliceous fragments scattered throughout."

Mar 1, 1943

By Katherine A. Margolis

Refuge Chamber Expectations Training was created by a multidisciplinary team at the National Institute for Occupational Safety and Health (NIOSH) to inform miners of what to expect psychologically and physically if it became necessary to use a refuge chamber in a mine emergency. The presentation can be used either for one large group or for individual miners. The training is a multimedia Adobe Flash presentation containing pictures, audio, video, and interviews with miners who have used a refuge chamber in an emergency. It must be run on a computer with Adobe Flash Player installed (refer to the computer system requirements section).

Oct 1, 2009

By Roy E. Peterson

The Bureau of Mines has been developing and evaluating methods for beneficiating the large deposits of nonmagnetic (oxidized) taconite located on the western Mesabi Range. In this segment of the research, a sample representing about 0.5 billion tons of nonmagnetic taconite from near Grand Rapids, Minn., was beneficiated using a reduction roasting, magnetic separation, flotation process. The sample contained 32.1 pct iron and 49.1 pct silica. Tests were conducted both on a bench scale and with a 1,000-lb/h pilot plant. In the bench-scale research a con-centrate containing 69.0 pct iron and 4.5 pct silica was produced with an iron recovery of 82.1 pct. In the pilot plant, reduction roasting was conducted in a 35-ft kiln using lignite as the reductant and major source of fuel. Dust from the kiln exhaust was pelletized and recycled to the kiln. The roasted taconite was beneficiated by magnetic sep-aration and flotation to produce a product containing 67.9 pct iron, 5.5 pct silica, and 69.7 pct of the iron in the kiln feed. The cyclone separation in the grinding circuit was sharpened by demagnetizing the cyclone feed in a 400-Hz, 1,000-Oe magnetic field.

Jan 1, 1983

By David E. Siskind

The Bureau of Mines studied environmental blast effects in six occupied residential structures. Airblast, ground, and structure vibrations were measured both inside and outside residences for seven quarry production blasts. Walls and floors responded to the blast noise and vibration by shaking at their own natural frequencies, often with greater peak particle velocities than the ground outside the structures or their foundations. The vibrations of the houses generated noticeable internal noise, correlating with the arrival of the groundborne energy. The later arriving airblast wave was predominantly at low infrasonic frequencies (1.0 to 1.5 Hz) and had similar amplitude and frequency characteristics both inside and out-side the structures. Significant structural motions resulted from the air-blast overpressures for at least two of the seven blasts. The most severe airblast effect occurred at a house 1,800 feet from a 5,047-pound (200-lb/ delay) blast. This stucture was subjected to a peak 0.16-in/sec particle velocity and 130 dB(L) airblast. The wall of the second floor responded to the ground vibration and airblast by shaking at particle velocities of 0.15 and 0.28 in/sec, respectively. Analysis of these data and those from additional field studies will be used to identify appropriate, safe, and reasonable impulsive noise levels, measurement techniques, and factors of design applicable to minimizing the adverse environmental effects of blasting.

Jan 1, 1976

To find solutions for common safety problems encountered in the handling of trailing cables, based on observations at many different surface mining operations. Approach Practices in handling trailing cables were Investigated through personal visits to over 40 mines, supplemented by visits to cable manufacturers and cable repair service companies. The most effective solutions to the safety problems en-countered were noted and are described In the project final report. Examples are given in this Technology News. Accident Experience Most cable-related injuries occur as a result of workers lifting, pulling, tripping, or being struck by the cable. The Table gives the frequency of occurrence for injuries reported during a recent 3 1/2 year period.

Jan 1, 1982

By M. M. Tilman

As part of ongoing research to improve mine safety, the Bureau of Mines conducted research on the corrosion of friction rock stabilizer steels in five Missouri lead and iron mine waters. Electrochemical corrosion tests, including evaluation of pitting tendency, were performed on two types of high-strength, low-alloy (HSLA) steels and galvanized steel in four Missouri lead mine waters and one Missouri iron mine water. The tests were conducted at in-mine water temperatures in both air-saturated and deaerated waters. Static, weight-loss corrosion tests were also conducted on HSLA steel specimens in the five Missouri mine waters for 2,900-h duration at average in-mine water temperatures and air-dissolved oxygen contents of 6 to 7 ppm. Corrosion rates determined by the weight-loss tests were roughly comparable with rates determined electrochemically in deaerated waters containing 0.3 to 0.5 ppm dissolved oxygen content. Passivation of specimen (nongalvanized) surfaces in air-saturated waters resulted in very low electrochemically deter- mined corrosion rates. Pitting-tendency was generally higher for both HSLA steels in air-saturated waters than in deaerated waters. Galvanized steel generally exhibited higher tendency to pitting in the deaerated waters than in the aerated mine waters.

Jan 1, 1985

By A. E. Petersen

To reduce U.S. dependence on imports of titanium, the U.S. Bureau of Mines has investigated the recovery of titanium from perovskite (CaTi03). Domestic perovskite deposits represent a significant, but untapped, titanium resource. An acid sulfation method was developed that will extract about 97 pct of the titanium and the columbium and 70 to 90 pct of the rare-earth byproducts from perovskite concentrates. A flow-sheet for recovering titanium as pigment-grade titanium dioxide (Ti02) is discussed. Test work performed in developing each unit operation is described. The first three unit operations have been demonstrated using laboratory-scale continuous methods of operation: acid sulfation of perovskite concentrates, leaching sulfation residue to dissolve metal values, and precipitation of titanium oxysulfate monohydrate (TiOS04?HP) from the resulting leach flltrate. Batch testing of other unit operations was performed: TiOS04?H20 redissolution and iron reduction, precipitation of Ti02 by hydrolysis, and regenerating recoverable acid with rare-earth byproduct recovery. Cost evaluation results are provided, indicating that processing perovskite concentrates by acid sulfation may be an economically viable means of producing Ti02.

Jan 1, 2010

By G. L. Oldright

This paper is the third1 of a series of five papers that is to appear on smelting in the lead blast furnace. The objects of this investigation are to determine the conditions obtaining within the blast furnace be direct experimentation, and to correlate the behavior of the furnace at various times with the main factors governing the operation of the blast furnace, and metallurgical losses. ACKNOWLEDGEMENTS The writers wish to express their appreciation to the management of the international Smelting Company at Tooele, Utah, for their kind cooperation which made possible the assembling of these data.

Jan 1, 1929

By H. B. Humphrey, F. E. Cash

The following information on accidents in Alabama during 1930 was compiled from data obtained from the companies represented in a course on accident prevention given by the United States Bureau of Mines in Birmingham. These mines produced nearly three-quarters of the tonnage of that State for the year, and included most of the larger operations in the district. The figures are probably representative of the mines which are doing recognized safety work, and are better than the average for all the mines in Alabama. Table 1 lists the days lost in accordance with the weights given to fatalities and permanent disabilities, part and total, which is the scale used in the National Safety Com¬ petition for Mines, conducted by this bureau. By way of explanation, temporary disabilities are weighted according to actual number of calendar days of disability, including Sundays and holidays — that is, all days are counted except the day of accident and day of employee's ability to return to duty. Hernia is classed as a temporary disability to be charged with the actual number of calendar days during which the employee was unable to work. Table 2 gives the number of accidents and the days lost from each cause at 45 coal mines and 7 iron ore mines, also the average frequency and severity rates.

Aug 1, 1931

By BUREAU OF MINES

In 1948 the United States became a net importer of oil. Coupled with an unprecedented domestic production of 5,900,000 barrels daily, imports approximating 500,000 barrels made available a total supply of 6,400,000 barrels a day. Thus, by a herculean effort, the oil industry was able to meet an extraordinary demand at home and, in addition, to ship abroad almost 460,000 barrels daily of petroleum and products. The country’s oil position now differs greatly from that prevailing at the beginning of World War II. Then, actual oil production averaged about 4 million barrels a day, and productive capacity probably was greater than 5 million barrels a day. As the demand of the military and industrial machine grew with the rising tempo of the drive toward victory, the United States not only met its own needs but produced about two-thirds of the total oil requirements of the Allied Nations, excluding Russia. As a people, we can be deeply grateful that the Nation’s petroleum resources were adequate and sufficiently developed to support such a tremendous effort. Even in those critical hours when immediate needs were the paramount issues, a prudent Congress paused to contemplate the importance of an assured long-term supply of liquid fuels. From these deliberations came the Synthetic Liquid Fuels Act of 1944, which authorized research and development work on new sources of oil – coal, oil shale, and agricultural and forestry products. Since World War II, a civilian demand for 6 million barrels of petroleum products has become the order of the day. By drilling as many as 39,000 new wells a year, the production rate has increased enough to meet domestic requirements by a bare margin. Some imports were necessary, however, to fill both domestic and foreign demands, and these doubtless will increase. Is this policy of exploration within the United States and the development of oil in foreign countries adequate insurance for the fulfillment of our future national needs? This question has two aspects – one purely civilian and economic in character and the other significant from the standpoint of our national defense. There are now approximately 4,000 producing oil fields in this country. At first thought, it would appear that production could decline in a considerable number of these fields without materially affecting the overall daily output. However, 48 percent of the oil comes from only 111 major fields which contain 60 percent of the total proved domestic reserves. It is apparent, then, that the flow from large fields – having proved reserves of 100 million barrels or more each – must be sustained if daily production is to be kept at the present levels. Essentially, this means that new major fields must be discovered about as rapidly, or perhaps more rapidly, than the older ones lose productive capacity. From 1940 through 1947, only eight major fields with estimated reserves of more than 100 million barrels each were discovered and proved – an average of one such field a year. The total estimated reserve of these eight fields was less than 1 year’s supply at the present rate of use. As drilling continues, some existing fields ultimately will prove reserves larger than those now known. Without a pronounced increase in the number of major discoveries, however, the prospects for increasing our present productive level are not encouraging. Any gap that appears between domestic productive capacity and demand could be filled with supplies from proved oil resources abroad. Assuming cheap pipeline and tanker transportation to the United States, freedom from exorbitant taxes and charges...

Jan 1, 1949

By John C. Machisak

THE INJURY data and experience at quarries and related plants of the United States are presented in this publication under the following general sections (A) General injury experience: Tables 1-3: Current data on number of injuries, injury-frequency rates, location, accident agency, degree of injury, and related employment data. (B) Injury experience at different kinds of quarries: Tables 4-5: Current data on number of injuries, injury-frequency rates, location, accident agency, degree of injury, and related employment, data. (C) Injury experience by States: Tables 6-20: Current data on the number of injuries, injury-frequency rates, accident agency, degree of injury, and related employment data. (D) Selected injury data: Tables 21-30: Current data on various selected factors of operating conditions at different kinds of quarries, including employment size-groups, length of shifts, comparative severity of injuries, and injury data and related employment experience at dimension-stone and nondimension-stone quarries and at underground quarries. (E) Historical injury experience: Table 31: Injury and employment data on the quarrying industry for 1911 through 1957. Statistical data on injuries and related employment in the quarrying industries have been collected annually from the operating companies since 1911. Reporting to the Bureau of Mines is voluntary; there is no Federal law compelling operators of quarries and related plants to supply such data. Data presented herein may not be complete for the entire industry. They are however, believed to be representative of the hazards common to all quarry and related workers. Moreover, the figures are comparable as between States-a significant fact in view of the lack of uniformity among the States with regard to the classes of injuries covered by State reports and other factors that tend to make it impracticable or impossible when using State records to

Jan 1, 1960