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By D. Harrington

This circular presents part I of a review of the literature on effects of breathing dusts, with special reference to silicosis, largely in the minim; and allied industries. The literature on this subject is so extensive that no attempt has been made to include all published material but only to assemble some of the more outstanding data on several aspects of the subject. Parts II and III will deal with prevention and treatment of dust diseases and some of the economic and legal aspects of dust diseases in industry, with special reference to mining. Dust diseases arc much before the public at present, and there is good reason to believe that the information on the subject available to the layman is extremely meager; even those rated as experts usually have a more or less theoretical conception of the diseases, their causation, remedies, and prevention, rather than actual experience with them. Until recently little attention has been given to prevention, and the usual attitude of the engineer, upon whom the main reliance for prevention ultimately must devolve, has been to let "sleeping dogs lie" or, more definitely, to "let well enough alone." However, the "laissez faire" attitude no longer is tenable, and in the past few years numerous conditions have caused those engaged in industry, including mining, to bring the subject before the public with a view to ascertaining the facts upon which to formulate remedial measures, primarily preventive.

Jan 1, 1935

By M. D. Marshall

A survey showed that there were 24 bin-related fatalities in the 5 year period of 1975 to 1979 in the minerals industry. Only 4 victims wore safety belts and only 1 of these had a second person attending his lifeline, as mandated by Federal safety regulations. Not one victim observed the three main Federal safety regulations governing work in and around bins. A study was conducted on the force necessary to pull victims partially buried in sand and limestone. Recommendations are made on procedures and safety equipment that can minimize bin-related accidents. A Handbook, directed to the plant engineer responsible for bin design and safety, was also issued detailing bin designs and flow-aid accessories as a function of the flowability of the stored material to better maintain material flow from bins. A comprehensive table of the flowability of many materials produced in the minerals industry is presented and simple procedures given for determining the flowability of materials if not available.

Jan 1, 1984

By J. S. Berber

Bastnasite is a natural fluocarbonate of the cerium group and affords an abundant and high-grade source of the lighter rare-earth elements. As part of a broad research program in rare-earth element technology, the Federal Bureau of Mines directed extensive experimental work to separating and purifying the rare-earth elements in bastnasite. By the use of a combination of techniques--classical chemical, ion exchange, and solvent extraction--the processing of a bastnasite concentrate to obtain the individual rare-earth elements, or groups of elements, was accomplished. A bastnasite concentrate, containing about 60 percent rare-earth oxides, was sulfated with concentrated sulfuric acid to eliminate the carbon dioxide, fluorine, and silica. Calcination at 1,200° F. made the gangue matter insoluble, thus permitting the separation of the soluble rare-earth sulfates. Essentially 100 percent of the rare-earth elements were recovered by this procedure. Since the rare-earth sulfate solution contained only trace amounts of nonrare-earth elements, subsequent separation procedures were simplified.

Jan 1, 1960

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 G. Stecklein

This report summarizes the results of research into the areas of the fragmentation and entrainment of Airborne Respirable Dust (ARD). The objectives of this program were four-fold: first, to review the present state of knowledge regarding ARD; second, to expand this state of knowledge through the identification of hypothetical microscopic mechanisms by which the coal is fragmented and the dust becomes entrained; third, to specify the informational requirements to verify or nullify these hypotheses; and fourth, to relate experimental techniques that will produce that required information. Additionally, insights are provided regarding potential methods of extraction and/or treatment which may reduce the concentration of ARD.

Jan 1, 1982

By J. J. S. Sebastian

The process development described in this report was carried out at the Morgantown Station of the U. S. Bureau of Mines in cooperation with West Virginia University. An experimental laboratory-scale pilot unit to gasify coal dust in entrainment was constructed on the Campus of the University in Morgantown. The enormously accelerated demand for liquid and gaseous fuels and utilization of our immense coal resources require that a low-cost process be developed for the gasification of a wide variety of coals. Such a process would be a major factor in lowering the cost of synthetic liquid fuels. None of the proc3sses developed in Germany prior to and during World War II, such as the Winkler process, the H. Koppers dust gasification process, the Wintershall-Schmalfoldt process, etc., meet all the requirements for a low-cost process under American conditions. Nor has any other process designed and experimentally operated at atmospheric pressure during the post-war period in this country appeared to fulfill all of the necessary conditions for a low-cost process.

Jan 1, 1950

By J. R. Thoenen, J. D. Warne

"INTRODUCTION Red-iron-ore deposits in northeast Alabama have been exploited at vari¬ous times for nearly 6o years. About 3-1/2 million tons of ore have been produced in the Gadsden district; but mining activity has been dormant since 1926, and furnaces within this section of the State now suffer a shortage of red ore.To alleviate these shortages, work by-the Bureau of Mines was recommended after preliminary investigations. 4/5/ Diamond drilling, to determine the lateral and vertical extent of ores of known deposits in Greasy Cove and on Shinbone Ridge, was done from August 1946 to May 1947, as Project 9-106, Alabama Red Iron Ore. Three holes were drilled in each area.ASKNOWLEDGMENTSIn its program of investigation of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of domestic mineral resources to the end that they- make the greatest possible contributions to the national security and economy. It is the policy of the Bureau to publish the facts developed by each project as soon as possible after its conclusion. The Mining Division, Lowell B. Moon, conducts preliminary examinations, does the actual investigative work, and prepares the final report. The Metallurgical Division, Oliver C. Ralston, chief, analyzes samples and makes beneficiation tests."

Jun 1, 1948

By T. M. Barczak

Longwall tailgates in coal mines are often subject to severe mining induced loading and deformation. Innovative tailgate supports have been developed over the years to provide safe and economical access and a ventilation pathway at the tailgate. The support capacity and yield capabilities of the supports need to be matched to the loading imposed by the surrounding rock mass. The ground response curve can be used to represent the rock mass response to mining and its effect on support systems. The FLAC finite difference code was used to supplement field results by simulating a longwall tailgate and the associated ground response. The ground response curve is developed by modeling tailgate excavations with different internal support pressures and recording the resulting convergence. Ground response curves are developed for two typical longwalls operating in the Pittsburgh seam with weak and strong immediate roof. An additional model is presented in which the effect of weak overburden strata is simulated. The ground response is shown to be significantly affected by the strength of the immediate roof as well as the main roof. The importance of yield capacity of standing support is demonstrated. Gob height and compaction are found to affect the amount of convergence in the tailgate. The potential exists to develop site specific tailgate design curves by combining model results with field observations.

By S. E. Burton

The White Rock area of the Boiling Springs manganese-iron deposits comprises about 3,200 acres of land in Monroe Township, Cumberland County, Pa. (See fig. 1.) This property was brought to the: attention of the Bureau of Mines by Pennsylvania Geological Survey Bulletin 128, entitled "Manganese Ores of Pennsylvania" by R. M. Foose. It was examined by an engineer of the Bureau of Mines in August 1942 and was further investigated by the Bureau by churn drilling and underground development during the period December 1942 to February 1944. Beneficiation tests were made on samples of the ore. This report describes the work done during the investigation and presents the results obtained.

Jan 1, 1949

By Peter Grandone

"INTRODUCTION The Bureau of Mines, recognizing the importance of knowing the evapor¬ation losses of aviation gasoline as larger quantities of this material must be stored, has made studies at a large refinery in the Texas Panhandle area during the past 13 months to determine the magnitude of the losses, by evaporation, under different storage conditions. Proper storage of aviation gasoline is very important, not only because large supplies are being stored for military use but because the specifications to which his fuel must conform are very rigid. Aviation gasolines that conform present-day specifications are blended from base-gasoline stocks (in some instances relatively pure hydrocarbons), each of which has different physical and chemical characteristics. Consequently, partial loss of any one of the more volatile components from the blended fuel results not only in material loss of the blended fuel but also may affect the characteristics or performance of the gasoline. One characteristic that has considerable influence or the vaporization tendency of gasoline is vapor pressure; and although the vapor pressure of aviation gasoline usually is lower than that of average commercial motor fuel, the quantity of certain components having relatively higher vapor pressure is greater in aviation gasoline, so that under prolonged storage the evaporation loss of these components may be appreciable."

May 1, 1943

By W. W. Roepke

The Bureau of Mines has developed an interactive computer program that enables mine operators and others to identify the effect of cut-ting system changes on relative dustiness at the face. The program, which simultaneously evaluates machine parameters, coal seam parame-ters, and operator-controllable parameters, was developed for use on any microcomputer using BASIC programming language. The program allows the user to change one or more of the cutting system parameters at a time to see how these changes affect relative dustiness. A complete program listing and flowchart are included along with operating in-structions and sample outputs. An example showing how to use the program is also included.

Jan 1, 1985

By K. L. Paciorek

The primary objective of this program was to determine the toxic fume and fire hazard of elastomeric noise abatement materials with a limited effort expended on the evaluation of specific treatments applied to mine timbers. Under the conditions employed, for a dimethyl silicone rubber, formaldehyde presented the major toxic threat; acrolein was the main toxic species for both polyester and polyether urethanes and an acrylonitrile-butadiene-styrene resin; in the case of flame-retardant styrene-butadiene rubber compositions, hydrogen chloride, and in the case of PFA-treated timber, furfural, were the major toxic compounds. Of the materials studied, the flame-retardant styrene-butadiene rubbers presented the greatest toxic hazard. The generated data have been reduced to toxic load tabulations amenable to employment for potential hazard assessment.

Jan 1, 1982

By S. H. Ash

THE MAGNITUDE of the anthracite industry's drainage problem in the Lackawanna River drainage area is realized when it is known that in 1948 the 27 pumping plants in this region pumped over 48 billion gallons of water to the surface from the mines in the Lackawanna Basin of the Northern field. This is almost 92,000 gallons per minute pumped against an average hydrostatic head of over 300 feet for that year. By comparison, Lake Wallenpaupack, the largest artificial body of water lying wholly in Pennsylvania, contains 71 billion gallons of water in its 24-square-mile area: the volume of water pumped from the mines in the Lackawanna Basin during 1948 was approximately 68 percent of that impounded in Lake Wallenpaupack. The Lackawanna. River and its tributaries drain a troughlike area of 345 square miles. The synclinal axis of this trough lies within the coal measures. All surface drainage into the valley must traverse some part of the coal measures. On the basis of 45.03 inches of rainfall recorded by the Scranton station of the United States Weather Bureau for 1948, the runoff from the Lackawanna River drainage area during that period was 135 billion gallons, approximately three times the volume of water pumped by all mine pumping plants in the Lackawanna. Basin of the Northern field during 1948. In other, words because of the pervious condition of the strata overlying the mine workings, approximately one-third of the total runoff in the Lackawanna River drainage area becomes mine water. This report, reveals that less than 7 percent of the 72 miles of pervious stream beds examined between Archbald and Pittston have been unproved.

Jan 1, 1952

Bag stackers who use semi-automated palletizing machines and air slides may be exposed to high concentrations of dust. To reduce dust exposure, use an exhaust ventilation system in conjunction with an envelope of clean air over the bagstacker provided by an overhead air supply. Description of Hazard Mineral processing plants in the United States and throughout the world process material that is finely ground and placed into bags for shipping to the consumer. These bags normally range from 50 to 100 pounds in weight. Once the material is placed in these bags, a bag stacker loads the bags onto pallets. A bag stacker is exposed to a lot of dust that is mainly released by the force from loading the bag onto the pallet. The two main sources are the dust on the outside of the bag and the dust that escapes from inside the bag as it is loaded. The Mine Safety and Health Administration's (MSHA) records indicate the bag stacker's dust exposure is one of the highest of all workers at mineral processing operations. Ways to reduce the dust exposure and strain to the bag stacker are in constant development. Recently, automated systems have been built. These systems range from fully automated, which totally remove the worker from the bag-stacking process, to semiautomated systems, in which the bag stacker still performs some of the functions. This Hazard Control deals with controlling the bag stacker's dust exposure during use of a semi-automated palletizing machine. The worker slides the bags into position on the palletizing machine. Once an entire layer of bags is positioned, the bag stacker operates the controls on the palletizing machine to lower the layer of bags onto the pallet. An air slide is built into the semi-automated palletizing machine so the bags are easier to move. This slide uses a metal table with air jets that exit through small holes at high velocities, similar to an air hockey game. The dust problem occurs because the air slide causes dust to blow up onto the bag stacker, significantly increasing the dust exposure.

Jan 7, 2001

By J. A. Ruppert, P. M. Sullivan

A process was developed on a laboratory scale in which iron contained in galvanizers ' zinc dross and aluminum contained in scrap zinc die - cast alloy were removed simultaneously . Melting both types of scrap together in the proper proportions resulted in formation of solid intermetallic Fe₂ Alg , which was readily removed from the melt by filtration and centrifugation . Recovery was 87 to 92 percent of the available zinc . Refined filtrate contained 0.02 percent iron and 0.20 percent aluminum. Aluminum content was further reduced to less than 0.01 percent by fluxing with zinc chloride . Low temperatures employed and inexpensive equipment requirements make the process commercially attractive .

Jan 1, 1964

By H. E. Powell

The magnetic susceptibility, the geographical source, and associated minerals are given for 44 copper-, 26 lead-, and 19 zinc-bearing minerals. Of the 44 copper minerals/ all had a susceptibility of less than 15 X 10-6 cgs, and about 20 percent of them were diamagnetic. Of the 26 lead minerals, all had a susceptibility of less than 11 X 10-5 cgs, and almost half of them were diamagnetic. And, of the 19 zinc minerals, all except four had a susceptibility of less than 9 X 10-6 cgs, and about one-fourth of them were diamagnetic.

Jan 1, 1968

By David C. Oyler, Hakan Gurgenli, Gregory M. Molinda

Historically, miners have known that roof rocks originally composed largely of mud were prone to slaking and deterioration when exposed to water and humidity. Mine Safety and Health Administration (MSHA) records show that roof falls are more prevalent in summer and late fall. Field data shows higher bolt loads and increased room convergence in summer months. Laboratory data shows that very high internal pressures can be generated by significant strain in clay-rich rocks. In summer months humidities ranging from 70-100% can cause rock strains up to 7%, and rock pressures of 14,000 psi, more than enough to break apart weak shales and fireclays. The National Institute for Occupational Safety and Health (NIOSH) conducted wet/dry immersion cycling of clay-rich rocks. Results show that the rocks most prone to moisture deterioration are fireclays, claystones, and sandy shales, all of which have disrupted bedding. Of the 7 mudrocks with a weatherability index above 40%, none showed consistent fissile bedding. Black shales were surprisingly resistant to wet/dry water immersion cycling. Generally, mixed rocks (stackrock), typically susceptible to horizontal stress, are more resistant to moisture-deterioration. Mine roof rocks tested with moisture sensitivity ratings above 50% (moisture sensitivity index ranges from 0-100 with 100 being the most sensitive) all came from mines which had roof skin problems and used supplemental support to prevent rock fall injuries. Some roof rocks showed lateral variability of moisture sensitivity values, suggesting the need for more samples in highly varying roof rocks. Swelling strains of mudrocks showed that almost all of the swelling occurred in the first 24 hours after immersion. The wet/dry immersion cycling test used provides an accurate, quick and inexpensive method for estimating the moisture sensitivity of mudrocks. With this information mine operators can begin to anticipate hazardous ground and prepare appropriate roof support.

By Bill Linville

Producing oil, gas, and coal in sufficient amounts to satisfy U.S. demands for fuels, electrical power, and chemicals promises to be one of the country's major challenges during the 1970's. Adding significantly to this challenge is the urgent task of satisfying soaring fuel and power demands without destroying the natural environment or jeopardizing long-range requirements for resources. The Bureau of Mines, U.S. Department of the Interior, is engaged in a comprehensive program of research to help industry meet this challenge. This report reviews the aims of the research program and accomplishments in 1970; the first 11 sections cover coal programs, nine sect ions are then devoted to petroleum, and the concluding five sections deal with oil shale research. Figure 1 shows the nationwide distribution of Bureau of Mines energy research installations; Full addresses are given in appendix A. Many of the publications resulting from the Bureau?s energy research efforts are discussed throughout the report; others are listed in appendix B.

Jan 1, 1971

By J. D. Noll

Elemental carbon (EC) is used as a surrogate for regulating the exposure to diesel particulate matter (DPM) of underground metal/non-metal miners. EC was chosen as a surrogate because EC is selective to DPM and is a major component of DPM. Using EC as a surrogate also gives one the advantages of no sampling artifacts and being able to sample at all locations in the mine. Currently, EC represents DPM well in underground mines. Some control technologies have been shown to possibly alter the relationship between DPM and EC and characteristics of DPM. Therefore, future work will investigate the relationship between DPM and EC as new control technologies are implemented.

Jan 1, 2002

By F. Matanzo

[Nine wire rope terminations were pull tested and fatigue tested to destruction to measure the termination efficiency and relative fatigue life. The terminations were selected on the basis off mine site visits and the specimen were assembled in a manner similar to industrial slings. To measure a termination's sensitivity to poor workmanship, both standard and modified assembly specimen were tested. Lang and Regular construction of the 6x19 and 6x37 class wire ropes were used in diameters of 13 mm (1/2 in.), 19 mm (3/4 in.), 25 mm (1 in.), 38 mm (1 1/2 in.), and 51 mm (2 in.). In static pull tests rope class, construction, and diameter interacted with the termination to influence the efficiency of the termination. In axial fatigue tests using only the 6x19 class rope, the effect of rope construction was negligible since failure was primarily dependent on the termination type. The Swaged Socket, a termination requiring a high capacity hydraulic press, gave the best overall performance in terms of efficiency and fatigue life. The short body length of the Zinc Poured Socket (RR-S-550) was attributed with the short fatigue life of this termination. The use of thermosetting resins as a replacement for zinc was demonstrated successfully for some socket designs. The fatigue life of the termination, expressed as a percentage of the fatigue life of the wire rope, was shown to be a guide for the retirement of the wire in these applications where the wiry' rope is primarily in axial loading.]

Jan 1, 1978