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By W. O. Philbrook

Reduced-scale models have long been used in hydrodynamics, aerodynamics, and heat transfer for studying fundamental flow relations or the performance of prototype designs under prescribed conditions. The pilot plant is a common tool of chemical engineering for investigating process variables and as an integral step in developing a new process. The metallurgical industry was rather slow to recognize the applicability of these techniques to some of its established and rather complex processes, but there has been a rapidly increasing number of applications of the principles of modeling in process metallurgy since World War II. Not only have pilot-scale operations been employed for developing methods of extracting metals that have recently achieved commercial importance, as well as new processes for some of the commoner metals, but models have also been used for engineering studies aimed at better understanding of the controlling, variables of time-honored conventional processes, It appears that the principles of similitude have become accepted as a useful tool, when properly applied, in metallurgy as in other fields of engineering. Much of the work of the Pyrometallurgical Laboratory, Region V, involves study of high-temperature smelting and refining processes for ferrous and related metals in pilot-scale equipment, such as the experimental blast furnace, converter, open-hearth, arc furnace, and rotary kiln. It was appropriate for the work of this laboratory that guiding principles for designing apparatus and interpreting results should be set down and that a bibliography of related work should be available for reference. A summary of the principles of model study and a brief review of some of the more noteworthy general papers have been published elsewhere.3/ Also, the Bureau of mines plans to publish a report of investigations describing its experimental work in this field. The bibliography is presented here as a service to others who may have use for it.

Jan 1, 1958

By Warren E. Morrison

The continuing high-level performance of the domestic mineral and mineral fuels industries during 1966 was sustained by the longest business upturn in the Nation's history. Spurred by consumer demand at home and the defense production requirements of the Viet-Nam war, the rising trend of economic activity during the year was reflected in the upward movements of the major economic indicators. At yearend the gross national product (GNP), representing the value of all goods and services produced, stood at $740 billion, $58 billion greater than in 1965. Corrected for price changes, the real value of GNP in terms of 1958 dollars was $648 billion and represented an annual increase in economic activity of 5.4 percent. Some 74 million persons were employed during the year out of a total population of 196.8 million, while unemployment fell below 4 percent. The Federal Reserve Index of Industrial Production averaged 156 for 1966, up 13 points from the previous year. However a jarring note in the 1966 expansion, and one which affected the mineral industries in particular, was the increasing pressure on prices and the threat of inflation. From 1961-65 economic growth was facilitated by relatively stable wages and prices and only mild inflation. During the period average wholesale prices hardly moved while average consumer prices rose only about I percent per year. But this long run of relative price stability ended during 1966 when consumer prices rose 2.9 percent and wholesale prices were up 3.2 percent from the previous year.

Jan 1, 1967

By F. L. Klinger

CRUDE OIL refining continued to be the foremost industry of Bahrain in 1963. This island, the largest of a group 30 kilometers off the Saudi Arabian coast, is the site of the first petroleum discovery in the Persian Gulf and in the Arabian peninsular region. The island's only oilfield was discovered in 1932; exports of crude began in 1934 and the refinery was built in 1936. Although its crude oil has been less than 1 percent of annual Middle East output in recent years, Bahrain has been an important refining center for many years, processing a substantial portion of Saudi Arabian petroleum as well as all local production. The Bahrain refinery annually accounts for 17 percent 0 the petroleum products produced in the Middle East and 25 percent of the exports. Bahrain's mineral resources consist of oil, gas, and basic construction materials. Petroleum production and refining are the important mineral industries and contribute most of the national income by payments for taxes, wages, and local services including construction and material supply. The petroleum industry has supported a large share of local business and extensive indirect employment, and its early establishment also helped Bahrain to strengthen its position as a trading center in the Persian Gulf. The country's entrepôt trade produces about 20 percent of Government revenue, and Bahrain is somewhat less dependent on the petroleum industry than are the neighboring States to the west.

Jan 1, 1964

By John C. Edwards, Gene F. Friel, John J. Opferman, Robert A. Franks

As the use of deep -rut mining increases, there - expected to be a greater demand for methane (CH,) measurement devices capable of scanning working faces al depths in excess of 10 m to alert mine personnel of hazardous concentrations of CH and to satisfy regulatory requirements. Remote optical devices offer the most promise to satisfy these objectives while the operator remains safely under supported roof. A second¬-generation remote Optical methanomeor (ROM) bas been designed and Is undergoing laboratory evaluation at the National Institute for Occupational Safety and Health. It operates on the principle of differential absorption of the "u;' fundamental absorption band of CH, centered at 3.31 um in the infrared region of the spectrum. The new instrument differs from the previous prototypes by the replacement of the two hand pass differential absorption technique of measurement with a single filter gas correlation technique and a refinement of the amplifier and gating circuitry used within the unit. This results in a more accurate isolation of the CH, spectral absorption band centered at 3.31 um. A specially designed 0.4m-diam variable-length gas mixing tunnel was constructed and instrumented with CH4 sampling capability to calibrate the ROM. Experiments have demonstrated the ability of the detector to respond to various conditions of CH, (pn•m) at distances as great as 12 m. Thermal radiation generated within the instrument is the controlling factor in the drift of the output signal nod, therefore the reliability of the instrument. Several approaches to reduce this extraneous radiation interfering moth the infrared detector, described, such as the installation of a fan in the instrument and thermoelectric coolers on the detector's beat sink. Implementation of this technology will significantly improve the safely of miners.

Jan 5, 1997

By M. J. Brevoort

Research work in the Bureau of Mines cryogenic laboratory requires the use of high-sensitivity galvanometers of the d'Arsonval type in a building that is subject to unusually severe vibrations. A modified form of the galvanometer suspension described by Julius' has damped the vibrations so successfully that a short note concerning it is thought to be desirable. The laboratory is on the site of the Amarillo helium plant near a building that houses gas engines of from 180 to 250 hp driving compressors and electric generators. The distances from the galvanometers to the individual engines range from about 80 to 180 feet. The subsoil, consisting of black clay loam, transmits the impulses without much damping. The usual methods of protecting galvanometers from vibration were tried and proved fruitless. A Julius suspension purchased on the market was carefully installed in the hope that it would overcome the difficulty, but the conditions were too severe even for this elaborate arrangement. Several modifications of the original Julius suspension, which were then introduced, resulted in almost complete elimination of all vibrational effects. These modifications were suggested by careful study of the original idea embraced in the Julius construction. They were designed to give further constraint to motion in any direction other than that parallel to a line from the point of support through the center of gravity of the suspension, This was accomplished by making the suspended frame more rigid and by improving the means of adjusting each of the supporting wires to the same degree, thereby transmitting any impulse symmetrically through the three wires. The result was a suspension that is more effective, particularly for severe vibration, than the form described by Julius; also, it is believed to have advantages in stability, simplicity, and ease of adjustment over the few suspensions for this type of service that the author has found described in the literature.

Jan 1, 1931

By R. E. Chaney

This report summarizes the research on the Strategic and Critical Materials Program tasks conducted at the Idaho National Engineering Laboratory (INEL) between May 1984 and April 1985. The work is divided into two areas: 1. Production Technologies - Tasks directed at developing advanced extraction technologies ? Biologically-Assisted Minerals Processing ? Metal/Gas Reactions and Thermal Plasmas ? Dehydration of Aluminum Chloride Hexahydrate (completed). 2. Conservation/Substitution Technologies - Tasks directed toward establishing the technical processing base which will permit the use of advanced materials ? Joining of Rapidly Solidified Alloys (RSA) ? Joining of Silicon Nitride-Based Ceramics ? Nondestructive Evaluation of Ceramic and RSA Joints and Materials ? Substitute Catalytic Materials for Platinum.

Jan 1, 1985

By Howard M. Stainer

Jan 1, 1963

By Howard M. Stainer

[Cover Page]

Jan 1, 1963

By R. R. Sayers

carbon monoxide mav occur in many places and inhalation of that insidious s is a. frequent and .videly distributed cause of poisoning, ranging in severity from headache and. inefficiency to unconsciousness and death. People are continual­ly being affected by carbon monoxide 1n the home, in garages, around gas and gasoline engines and blast-furnaces, in fighting fires, after blasting in mines and quarries, and after mine fires and explosions; in fact, everywhere there is the possibility of an exposure to the products of combustion of carbonaceous fuels or products, On the other hand, there are arzy' cases reported wherP. ill effects and acci:ients are wro:1gly .ttributed to carbon monoxide. Thus it is essential indeed for doctors, coroners, safety engineers, a.n1 !irst-aid men to be able to recognize this poisoning, not only as reeards giving proper treatment, but to ensure just decisions on claims and to eliminate false illusions and complaints of ·11orkrr.en.

May 1, 1922

By D. J. Parker

Du.ring the past two years a number of oases of successful first-aid treatn . .)nt have been reported by or through the employees of the O. s. Bureau of -anes safety cars and stations. Among such cases are the following: At Benbush, w. Va., a boy or 16 years of age who ba.d just started to work in the mines was trained in first-aid by the crew of Bureau of Mines car 8. The local rr.ine superintendent afterwards reported tba.t a few dS¥s later this boy, Melvin Hollingsworht, found droming in a spring a. baby about three years old who bad wandered away fron.. har.e alone. The boy rescued the baby and perf'oxmed artificial re­suscitation upon it, thu.s saving the child's life. The Schaefer method of resuscitation bad bean ta"Ugbt the boy as a routine art of the regular first-aid course.

May 1, 1922

By Lloyd M. Kniffin

[This paper is one of series being prepared by the United States Bureau of Mines on mining methods, practices, and costs in the various mining districts of the United States. It describes the mine of the Hanover Bessemer Iron & Copper Co. at Fierro, Grant County, N. M., which is the only operating iron mine in the southwestern part of the United States. This mine is in a district noted for the great variety of ores that it produces. Within a small area, as shown is Figure 1, there are noteworthy deposits of nearly all the common metals. The ore occurs in lenticular masses dipping at about 50°. An underhand stoping method has been developed that requires but a very small amount of handling of ore. As the ore is very irregular in iron content and also in the distribution of the impurities--chiefly sulphur, silica, and magnesia--a method has to be used that will permit selective mining and will also allow ore and waste to be taken out separately as conditions change. A magnetic cobbing plant raises the grade of the ore shipped about 10 per cent.]

Jan 1, 1930

By Robert F. Chaiken, Alex C. Smith

INTRODUCTION The National Institute for Occupational Safety and Health (NIOSH) at its Pittsburgh Research Laboratory (PRC) is interested in the application of water mist sprays to extinguish diesel fie1 fires in underground mine diesel refueling areas. To this end experimental studies have been carried out on the extinguishment of diesel fuel fires at PRL's large enclosed fire suppression facility (FSP) at its Lake Lynn Laboratory (LLL). Two sizes of shallow fuel pans (3x3 ft and 5x7 ft) contained the fires, and a number of commercial mist spray nozzles (at roof locations) and spray/fire locations were tested (52 fires in all). Visual observations of the pool fire extinguishment process by the overhead sprays with an infra-red sensitive videocom suggests that there are two distinct actions involved in extinguishment due to two different transport mechanisms by which the water droplets can enter the fire plume. First, is a direct injection of water droplets into the plume from overhead. This is believed to involve larger water drops and leads to an extinguishment time of several minutes. Second, is an indirect injection process involving small water drops which are entrained in the sideways air flow that feeds oxygen to the fire. This second process apparently leads to relatively fast quenching of the fire in less than 1 minute - a highly useful attribute for a fire protection system. This paper describes a relatively simple parametric model for the indirect water injection process, and defines the critical spray conditions for achieving rapid quenching of the pool fire. While the model is consistent with the pool fire data obtained to date, the PRL studies are continuing with more complex pool fire scenarios. It remains to be seen if this simple parametric approach applies to these future fire tests. THEORETICAL Critical Drop Size In the two-dimensional representation of figure I, an oil pool fire is considered to be a cone whose base is the vaporizing liquid oil surface having an area n?, above which exists a fire plume diffusion flame) of height, L. The rising plume induces a horizontal air flow into the side of the plume supplying the oxygen necessary for propagating gas phase combustion reactions. Water droplets suspended in the air around the plume will tend to follow the horizontal air flows into the plume. The rate of air entrainment by the plume will be determined by the overall combustion reaction which is assumed to be

By F. M. Goodwin, John Campbell, G. W. Jones

"INTRODUCTION In previous reports 5 results were given of a manhole investigation carried out over a period from June 1929 to July 193C in cooperation with the Edison Electric Illuminating Co. of Boston. Mass., and during 1931 in cooperation with the Edison Electric Illuminating Co. of Boston and the Boston Consolidated Gas Co., to determine the general hazards of combustible gases and vapors in manholes and other underground openings owned by the Edison Electric Illuminating Co. and to develop methods of eliminating these hazards. These investigations have demonstrated that the detection, control, and elimination of combustible hazards in manholes can best be obtained by a close cooperation of the interested parties through a systematic and continuous inspection of manholes, under proper supervision.The investigation carried out during 1932 has been along lines similar to those conducted during 1929, 1930, and 1931 test crew consisting of two men, one an employee of the Consolidated Gas Co. and the other an employee of the Edison Electric Illuminating Co., was continuously employed during the year in the testing of gases in manholes served by the Edison system. The test crew was under the direct supervision of John Campbell, superintendent of the special service department of the Edison Electric Illuminating Co., and F. M. Goodwin, vice president of the Consolidated Gas Co.As in the previous investigations, all tests were numbered. The test-data sheets, on which the information regarding the tests was recorded, were prepared in triplicate, ono copy going to the Edison Co., one to the gas company, and the third to the Bureau of Mines at Pittsburgh, Pa. These test-data sheets were then filed (1) according to the town, (2) the street location, and (3) the manhole number; in this way a complete record of each manhole tested was immediately available. A typical test-data sheet was given in the 1931 report. These data sheets were found to entirely satisfactory and no changes were made during the 1932 investigation. The procedure of sampling manhole atmospheres, shipment of the samples to Pittsburgh, and method of analysis has been the same as that described in the 1931 report and need not be repeated here. Likewise, there has been no change in the method of calculation of explosibility of the samples analyzed or the use of charcoal filter tests given in appendix A."

Jun 1, 1933

Objective The Roof Monitoring Safety System (RMSS) introduced in late 1997 has been modified to improve durability and simplify the measurement of roof or rib movement. Greater knowledge about the stability of roof and rib rock is expected to result in safer conditions for the mine worker. Developing safety tools and methods is part of NIOSH’s mission to prevent work-related injuries and deaths. A mining operation with a proactive approach to control ground conditions is in a better position to make essential decisions related to mine development and take remedial actions in the event of roof or rib falls. Background Falls of roof and rib rock are responsible for a high number of mining injuries and fatalities. Visual inspections and the sound of breaking or cracking rock are often relied upon to indicate unstable roof conditions. In some mines, roof bolt holes are checked for separations or gaps with a scratch tool; this provides further information about the stability of the roof. Monitors such as the RMSS can confirm roof movement that was surmised only by eye or ear, or potentially detect movement that was missed by these means. An added safety feature of the RMSS is the capability of locating the measurement station at a distance from where the monitor is placed in the roof. Stone and other industrial minerals are the basic raw materials used in construction. Continuing economic growth and highway building in particular have resulted in record demand for stone. This high demand, coupled with increasing constraints on surface mining, have caused many new .stone mines to be developed underground. These new mines in many cases will be employing new and inexperienced miners who may not have the ability to recognize unstable ground conditions using just sight and sound. From the initial introduction of the RMSS, it was anticipated that improvements and modifications would occur. We correctly assumed that, once miners and operators were exposed to the monitor. suggestions would evolve. In one case, the RMSS was used to determine if an impact hammer used on a mechanical scaler was causing or increasing instability of roof rock. The test showed little or no movement resulted from this method of scaling under the particular conditions at this mine. In another instance, an operator needed to monitor the stability of a haulageway in a benched area that had very high ceilings. The RMSS requires a 2-in-diam hole for installation; however, only roof bolt holes of a smaller diameter were available, and it was impossible to drill new holes at that height. The operator attached a 2-in collar at the roof line and was able to install the RMSS. These examples illustrate the potential for further enhancements of this tool. NIOSH continues to seek additional candidate sites for use of the RMSS. As usage increases, we anticipate further refinements and additional applications. How It Works The new RMSS, cable, and read-out box are shown in figure l. The read-out box has a green light that stays lit until battery replacement is needed. The red light is set to conic on to indicate movement. The red light can he adjusted for increments of movement as low as .010 inches. The RMSS red light should not be considered as a primary or only means of determining the stability of roof or rib. It is intended to serve as a supplement to existing methods or procedures for determining stability. An overview of the RMSS components is shown in figure 2. Movement of rock layers within the mine roof is measured relative to a fixed-point calibration at the monitor housing. The housing contains a potentiometer, roller switch, plastic rack, and spur gear. Movements are detected by the transfer of electromotive forces

Jun 1, 2000

To reduce operator exposure to noise from vibrating screens at coal preparation plants. Background Hearing loss is one of the most common occupational illnesses in the United States. In the U.S. mining industry, hearing loss is 2.5 to 3 times greater than what is expected for the average population that is not exposed to occupational noise. Furthermore, studies by the National Institute for Occupational Safety and Health (NIOSH) showed that by age 50, 90% of coal miners have a hearing impairment versus only 10% of the population that is not exposed to occupational noise. A NIOSH cross-sectional survey of coal preparation plants showed that 43.5% of employees were overexposed to noise. The study also found that vibrating screens were one of the top five loudest types of equipment at these plants?as well as the most numerous?making them a key noise source to address.

Nov 1, 2009

Although the Stamler feeder/breaker has been used for coal crushing in underground mines for many years, it has only recently been applied to other crushing operations. Two companies presently using Stamler feeder/breakers for rock crushing were contacted regarding their experiences with the units in actual field use. In both cases information was obtained directly from the individuals responsible for field operation and maintenance of the units. White Pine Copper Co. has been using Stamler feeder/breakers for over two years to crush copper ore. They now have fourteen 450-ton-per-hour units on line. The ore has a compressive strength of from 18,000 to 28,000 psi and is extremely abrasive. Maintenance is performed on a tonnage basis. The breaker shaft is replaced every 250,000 tons (requiring about 4 hrs) and picks are replaced about every 1500 tons by the operator (requiring about 2 min per pick). Very little unscheduled maintenance has been required. Crushing costs are fairly high (estimated at 13 to 15t per ton including maintenance and operation) because of tale extreme abrasiveness of the material. A new Stamler feeder/breaker with Ultramet wear surfaces was put or line in June 1976. Ultramet was found to increase the life of belt transfer station surfaces by up to 400 percent and it is hoped that it will do the same for the feeder/breaker. At this time it is still too early to evaluate the performance of the Ultramet unit. If it does improve abrasion resistance, crushing costs could be greatly reduced. White Pine is very pleased with the units and the service provided by Stamler.

Jan 1, 1976

Objective: To enable mine operators and mine inspectors to make quick and accurate measurements of the explosible nature of coal and rock dust mixtures.

Jul 1, 2008

Over and above the technical support arid consulting work described in the preceding Parts of this Volume, ADL staff also provided a wide range of additional technical assistance to the Bureau on an ad hoc basis over the course of the contract, and particularly in 1973. Some of these assignments were on tasks that temporarily assumed a high priority at PMSRC, requiring a fast response, while others were more suited to conventional schedules but on communication and location topics less directly related to those in the preceding Parts. Chapter I briefly describes some of the diverse short-term assignments while Chapters I1through V treat assignments on the other topics. I SHORT-TEXM ASSIGNMENTS A sampling of short-term, fast-response assignments undertaken on mine communications and miner location for PMSRC during 1973 are given below. These assignments included technical reviews, discussions and recommendations related to the theory, experimental data, designs, and hardware implementation of experimental CW and pulse miner location EM transmitters; preparation of technical performance specifications for a miniaturized preproduction prototype CW electromagnetic location transmitter; review of specifications for a seismic signal detection experimental study; participation in technical discussions and experiments with PMSRC and equipment suppliers regarding the UHF radio/radiax-cable communications installation in the Bruceton mine; participation in an informal conference to discuss mine communication and monitoring needs and preferences with representatives of the Bureau, mine operators, and equipment manufacturers; participation in technical discussions with representatives of a U.S. mine operator and CERCHAR* concerning the characterization of faults on trolley lines and means of improving their rapid detection;** recommendation of simple signal, noise, and ground fault measurements on mine phone lines; review of an inexpensive automatic telephone dialer; preliminary discussions regarding the feasibility of adapting and assembling a collection of available telephone industry carrier equipment for installation and test in an operating coal mine; evaluation of a proposed call alert mine paging system; review of hardware designs and future experiments for a mine communication sled; design critique of a proposed six-channel narrow-band FM voice modem for carrier communication on the mine phone line; preparation of technical performance

Jan 1, 1974

Wires leading to or from underground facilities can develop hazardous voltages because of lightning exposure. The locations of many mine portals are particularly susceptible to lightning effects. The application of protective devices to limit this potential danger is necessary.

Jan 1, 1975

By Charlie Wyche

Principal mineral products in the Dominion of Fiji were gold, silver, pit and quarry construction materials, and cement. In the years 1978-79, the combined total value of these commodities accounted for some $15 million,2 or 85% of the total mineral output. Production of cement, sand and gravel, and quarry products increased substantially, but gold and silver output from Fiji's only operating metal mine continued the down-ward trend of recent years. Mineral exploration by several international mining companies as well as by local prospectors was being carried out over much of Fiji, and a number of interesting prospects were discovered. One of these, a medium-size porphyry-copper prospect in the Namosi area of Viti Levu, W88 at a mining feasibility study stage. At Mount Kasi on Vanua Levu, an extensive program of geological sampling and mapping W88 being conducted, and surface sampling and drilling W88 taking place at some base metal prospects in the south-central parts of Viti Levu. Also, high gold values in surface samples were reported at Vuda in western Viti Levu.

Jan 1, 1981