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By Raymond W. Henn

The 32nd annual short course ?Grouting Fundamentals and Current Practice? was held at the Colorado School of Mines, June 13-17, 2011. The field demonstration portion of the course was conducted June 16 at Baski Inc.?s yard in Denver, CO. The full-scale field demonstration presents many types of drilling and grouting equipment in operation as well as numerous grouting methods per-formed under various field conditions. As part of the field demonstration, the class was shown the proportioning, mixing, testing and injection of various cement grout mixes into sand columns under controlled and recorded conditions. These sand column demonstrations have been conducted under controlled and measured conditions each year since 1999 as part of the short course. The sand column demonstrations were conducted prior to 1999, but with less quality control and minimal record keeping of the proportioning, mixing, testing, injection pressures and the final permeation results.

Jan 1, 2011

By Anthony H. Tawil

Modern, high-speed machines used in the manufacture of paper require foundations with stringent settlement constraints. To fulfill this requirement, caisson piles, extending into bedrock, were selected to support a paper machine in Baie Comeau for the Quebec North Shore Paper Company (QNSPCo.). This was the fourth machine in an existing paper mill, and its construction was part of an expansion program which included the building of associated structures such as a wood room and chip storage building, and other facilities, Figure 1. The paper mill in Baie Comeau, Quebec, is located in an area which has extensive deposits of sensitive marine clay which are transformed into a viscous liquid when disturbed by external forces such as the driving of piles. Loss of ground and soil disturbance as affected by piling activity assumed considerable importance in the design and construction of the caissons particularly in view of the proximity of existing plant facilities, including another paper machine.

Jan 1, 1987

By A. U. Miller

For many years Illinois has been one of the leading coal producers in the United States and as such its safety record has compared very well with the other large coal producing States , both in tons produced and millions of man -hours of exposure per fatal accident . ( See Table 25 in Bureau of Mines Bulletin 293. ) During the 10-year period from 1917 to 1926 , inclusive , the average production in the United States per fatal accident was 278 , 109 tons . The aver age for the State of Illinois for the same period was 409,249 tons . Illinois produced 450,464 tons per fatal accident, and in 1928 produced 390,630, tons , or an average of 419,721 tons for the 12- year period from 1917 to 1928 , inclusive . In 1927 During the year 1929 , the shipping mines of the State made a decided improvement in their record over any previous year . Table 1 shows the monthly production and the tons produced per fatal accident . During 1928 and 1929 safety work was actively carried on in Illinois . Safety meetings were held with mine officials , representatives of the State. De partment of Mines , and the United States Bureau of Mines . At these meetings mine hazards and accidents were discussed and remedies suggested for : their elimination in the future . It is believed that first - aid training was to a considerable extent instrumental in reducing accidents and in making the good safety records in Illinois during 1928 and 1929. During these years ( as well as in 1926 and 1927 to a somewhat less extont ) en intensive rirst-aid training campaign was con ducted in Illinois by the officials and members of the United Mine Workers of America , coal companies, State Department of Mines and Minerals , and the U. S. Bureau of Mines , Every first -aid class was made a safety meeting ; where accidents and general safety were discussed freely while teaching first aid. During this time , anproximately 25,000 persons were trained in first aid, and 17 coal companies were issued certificates for having 100 per cent of their employees. trained in first aid. Since January 1 , 1926 , more than 40,000 have received first -aid training in and around Illinois mines , and including those who received training previous to this date , it is believed that at least 90 per cent of the miners in Illinois have received first -aid training . This state ment is based on the fact that the labor turnover in Illinois is not large .

Apr 1, 1931

By R. Barany

This report contains the results of experimental work conducted by the Bureau of Mines to obtain the heats of formation at 298.15° K. of analcite, dehydrated analcite, lawsonite, anorthite, hexagonal anorthite, and leonhardite. Thermodynamic data for these minerals have applications in ceramics, extractive metallurgy, and particularly in geochemistry. Except for data on anorthite, no previous similar data existed. The present results will be a substantial aid in deriving the temperature-pressure-equilibrium relationships among these minerals. The heats of formation were determined by solution calorimetry, with hydrofluoric acid as the reaction medium. The results were expressed both in terms of the constituent oxides and in terms of the constituent elements. The heat of formation data were combined with related entropy values to obtain the free energies of formation at 298.15° K.

Jan 1, 1962

By Jose R. Hernandez-Aguilar

"Three models to predict the effect of bubble size (Db) on metallurgical response were tested in a pilot-scale flotation column at Teck Highland Valley Copper mine. The column was fed with slurry collected from the Cu/Mo separation circuit. The first model was the one developed by Gorain et al. (1997), which assumes that the collection zone rate constant (kc) is inversely proportional to Db. The second model was the one proposed by Hernandez-Aguilar et al. (2010), which considers kc as an inverse square function of Db. The third model was the one developed by Yoon and Luttrell (1989) which provides expressions to describe the efficiency of particle collection (E) based on first principles. The results showed a significant bias between experimental and predicted data using the model of Gorain et al. (1997), possibly reflecting the model’s inability to explain the impact of bubble size, bubble rise velocity and flow regime on E. The model of Hernandez-Aguilar et al. (2010) well described the experimental evidence. The model of Yoon and Luttrell gave accurate and unbiased predictions. However, Yoon and Luttrell’s approach calls for a criterion to determine whether the flow regime is potential or intermediate, a subject that requires more fundamental research.INTRODUCTIONParticle collection, i.e., bubble-particle collision followed by attachment, is the basis of flotation. In a quiescent environment (such as the one observed in a column, or away from the impeller in a mechanical cell), a collision event can take place as long as the “degree of turbulence” caused by the rising bubble does not prevent particle and bubble to flow in close proximity. Upon collision, the particle slides on the bubble surface for a period of time. If the particle is hydrophobic, attachment occurs when the “sliding time” is longer than the “induction time”, which is the time required to thin and rupture the intervening liquid (usually water) film forming a three-phase contact angle. While the induction time is largely influenced by the degree of hydrophobicity of the particle, the degree of turbulence is governed by the bubble size. Generally, direct control of bubble size is not exercised by most mineral processing practitioners, in spite of its obvious importance. Studies to model the effect of bubble size on particle collection using fundamental approaches have been conducted (e.g., Anfruns and Kitchener, 1977; Webber and Paddock, 1983; Yoon and Luttrell, 1989; Dai et al., 1999). However, these models have been validated under highly idealized laboratory conditions (micro-scale experiments using single minerals and uni-sized bubbles), far from resembling those existing in practical industrial applications. Fundamental studies to interpret the effect of bubble size on particle collection in industrial environments are largely absent in the literature. Partly because of this lack of practical knowledge, many mineral processing practitioners perceive laboratory “bubble size” studies to be valuable academic exercises, but not something that can be directly applied to daily production issues."

Jan 1, 2011

By Laurance L. Oden

The Bureau of Mines is developing nickel catalysts for converting synthesis gas derived from coal to synthetic natural gas. The present report describes the relationship between the composition of aluminum-nickel alloys in the composition range NiAl3 to Ni2Al3 equilibrated at 840° C and the properties of catalysts obtained from them. Methanation activity was determined in the temperature range of 300° to 360° C in a flowing gas stream containing 1 pct CO, 8 pct H2, and the remainder He. One part per million of H2S was added to the gas stream at 400° C to evaluate the susceptibility of catalysts to sulfur poisoning. The total surface area was measured by the adsorption of nitrogen at liquid nitrogen temperature, and the active surface area was measured by the adsorption of hydrogen at room temperature. Total surface area and active surface area were found to increase with increasing proportion of aluminum-saturated Ni2Al3 in the precursor alloy, but methanation activity and resistance to poisoning by H2S were nearly constant. However, the methanation activity of the catalyst prepared from stoichiometric Ni2Al3 was less than half that of the other catalysts.

Jan 1, 1978

By W. D. Dietzman

In view of the developments and recent interest in recovering heavy oil, this report was prepared to present general information on more than 2,000 heavy oil reservoirs in more than 1,500 fields in 26 states. Information given on each heavy-oil deposit includes the following items: Field and formation, location, average or range of depth, average API gravity of oil, aver- age thickness of formation, areal extent of field, total productive wells drilled in field, discovery date of field, field status in 1963, cumulative production to Jan. 1, 1964, and all known types of secondary-recovery operations initiated (active and terminated) in the reservoirs. The geographical location of heavy oil accumulations in the United States is shown by a map, and a brief discussion of 14 different areas is given in the text. As of Jan. 1, 1964, 75 percent of the heavy oil reservoirs in the United States had produced more than 10 billion barrels of oil and are estimated to contain over 90 billion barrels of oil in place. It is also estimated that if the deposits which have had little or no production history, such as the one in Missouri, were included, the total remaining heavy oil in place would be in excess of 150 billion barrels. To find economical ways of recovering this vast reserve of heavy oil, industry is developing technology in several types of thermal-recovery methods. Some of the general considerations and more suitable limitations in selecting a prospect to study fur thermal-recovery techniques are: Lithology, depth, viscosity of reservoir fluids, gravity of oil, reservoir thickness, oil in place, and permeability and porosity.

Jan 1, 1965

By W. D. Dietzman

In view of the developments and recent interest in recovering heavy oil, this report was prepared to present general information on more than 2,000 heavy oil reservoirs in more than 1,500 fields in 26 states. Information given on each heavy-oil deposit includes the following items: Field and formation, location, average or range of depth, average API gravity of oil, aver- age thickness of formation, areal extent of field, total productive wells drilled in field, discovery date of field, field status in 1963, cumulative production to Jan. 1, 1964, and all known types of secondary-recovery operations initiated (active and terminated) Fn the reservoirs. The geographical location of heavy oil accumulations in the United States is shown by a map, and a brief discussion of 14 different areas is given in the text. As of Jan. 1, 1964, 75 percent of the heavy oil reservoirs in the United States had produced more than 10 billion barrels of oil and are estimated to contain over 90 billion barrels of oil in place. It is also estimated that if the deposits which have had little or no production history, such as the one in Missouri, were included, the total remaining heavy oil in place would be in excess of 150 billion barrels. To find economical ways of recovering this vast reserve of heavy oil, industry is developing technology in several types of thermal-recovery methods. Some of the general considerations and more suitable limitations in selecting a prospect to study fur thermal-recovery techniques are: Lithology, depth, viscosity of reservoir fluids, gravity of oil, reservoir thickness, oil in place, and permeability and porosity.

Jan 1, 1965

A system to continuously measure the concentration of radon in mine ventilating air has been developed and tested in a uranium mine. In use, the air/radon mixture to be monitored is pumped through filters into a scintillation cell where nuclear decay of the radon produces flashes of light. These are electronically counted, giving a quantitative measure of the radon present. Air is continuously drawn from the mine atmosphere into the radon sensor box. This air sample passes through two filters into the detector cell as shown in the schematic diagram. A portion of the radon in the detector cell will experience nuclear decay, producing polomium 218 and an alpha particle. The alpha particles from the fraction that decays strike a zinc-sulfide coating on the inside wall of the cell and produce flashes of light. These enter a photo-multiplier tube which records each flash as an electrical pulse. An amplifier increases the voltage of each pulse, allowing electronic screening to remove noise and other undesirable pulses. The remaining pulses are counted by a conventional data acquisition system.

Jan 1, 1978

By Lowell Stroud

This report is the third in a series presenting equilibrium vapor-liquid data for helium-bearing natural gases. The first two reports contained phase data for the gases processed for helium at the Bureau of Mines Amarillo and Exell, Tex., helium plants. The present report offers similar information for a lower-helium-content (0.75 mole-percent) natural gas to be processed in the Department of the Interior's long-range helium-conservation program. A windowed-cell apparatus was used to obtain 218 samples of equilibrium vapor and liquid phases at 73 experimental conditions ranging in temperature from -100° F to -275° F and in pressure from 100 to 500 psi. From the phase data, the condensation characteristics, helium solubility, and equilibrium-vaporization-coefficient data for helium, nitrogen, and methane were evaluated. The effect of using a. preliminary hydrocarbon trap upon the subsequent vapor-liquid compositions is reported. A brief comment regarding the composition effect of passing the gas through a gasoline-removal unit is also included.

Jan 1, 1963

By W. W. Adams

"The eighth National Safety Competition, that for 1932, conducted by the United States Bureau of Mines, was participated in by 322 mines and quarries operating in 34 States. Tables 2 to 6 show the relative standing of the various plants. Bronze trophies, known as the 'Sentinels of Safety,' which were provided by The Explosives Engineer magazine to be awarded annually by the Bureau of Mines, were awarded to five companies, each company having established the best accident-prevention record within one of the five classes into which all companies were divided, - namely, anthracite-mining companies, bituminous-coal-mining companies, metal-mining companies, operators of nonmetallic-mineral mines other than coal mines, and quarries or open-cut mines. The trophies are awarded for one year and are then transferred to the winners of the succeeding year's contest.The trophy for bituminous-coal mines, which has been in New Mexico for the past year, was won by a mine in West Virginia. The metal-mine trophy goes to New York State for the first time in the history of the contest. Previously it had been won by mines in Minnesota, Michigan, Kansas, and Oklahoma. The trophy for nonmetal mines remains for another year at Retsof, N. Y.; that for quarries and open-cut mines is transferred to a quarry in Michigan. The trophy for anthracite mines, of course, remains in Pennsylvania, as all anthracite mines in the contest are in that State.In determining the relative standing of the various companies enrolled in the competition, all mines and quarries were graded according to their accident-severity rates, - that is, according to the number of days of disability of employees on account of accidents in proportion to the number of man-hours of work done by all employees at the plant. Reports of accidents and of man-hours worked were furnished by the companies to the Bureau of Mines. These reports were carefully examined and classified to insure uniform weighting of accidents according to the number of days of disability to be charged and to insure uniformity of methods of calculating the accident-severity rates for the various mines and quarries. When the relative standing of all plants had been determined in this way, a summary of the records of the companies having the lowest accident-severity rates in their respective groups was sent to the members of a committee of award for examination in accordance with the rules governing the safety contest. The members of the committee of award were W. H. Cameron, managing director of the National Safety Council; William Green, president of the American Federation of Labor; James F. Callbreath, secretary of the American Mining Congress; T. T. Read, Vinton professor of mining engineering of Columbia University; C. B. Huntress, executive secretary of the National Coal Association; A. J. R. Curtis, assistant to the general manager of the Portland Cement Association; and A. T. Goldbeck, director of the bureau of engineering of the National Crushed Stone Association. When two or more mines within the same group operated without an accident during the year, the contest rules provided that the trophy for the group should be awarded to the plant whose record showed the largest number of man-hours worked."

Jul 1, 1933

By Matthew S. Sanchez, Richard J. Lee, Matthew D. Zock, Drew R. Van Orden, Yumi Kamiya, Edward B. Ilgren

In many developing countries, asbestos is still used for friction products, insulation, and asbestoscement products. However, there is very limited modern data evaluating the airborne concentrations of asbestos fibers in operating asbestos plants. We have conducted an Industrial Hygiene survey, using state of the art PCM and TEM analysis, of a Bolivian asbestos cement plant that uses crocidolite during the production of roofing shingles and water tanks. The study is the first to use modern analytical measurements in an uncontrolled asbestos environment. Thus, this study offers insight into the historical airborne exposures at asbestos plants operating before modern dust control measures were introduced or airborne fiber levels regulated. The results suggest that fiber concentrations are far in excess of those for which current models would predict the onset of asbestos disease and mesothelioma. Significantly, the plant and community do not have an elevated incidence of asbestos disease or mesothelioma. Airborne fiber levels during comminution and fiber sizing ranged from 100 to as much as 1,000 f/cc. Fiber levels in the mixing, forming and finishing areas ranged from 0.5 to 9 f/cc. Based on the number of overloaded samples and estimates of their concentration, historical estimates of exposure may be underestimated by an order of magnitude. Also, an excellent correlation (1:1) between the PCM and TEM fiber concentrations (for fibers _0.25 um diameter) were obtained, raising questions about the conventional wisdom that the PCM systematically undercounts fibers. The results of this study further indicate that current models may overestimate the risk of asbestos disease and mesothelioma.

Jan 1, 2012

The contract objective was to evaluate sources of airborne quartz and research control methods that would assist underground mine operators in complying with respirable dust standards which have been reduced because of quartz in the dust exceeding five percent. The work involved: Phase I -evaluate sources of quartz dust at the roof bolter work location; Phase II -evaluate the relationship between the quartz content of the coal and adjoining rock strata and quartz exposure at the roof bolter and continuous miner locations Phase III -conduct laboratory tests to determine performance parameters for roof bolter dust collector systems. The underground surveys for Phases I and II determined: (1) the continuous miner typically is the greatest source of quartz exposure for the miner and roof bolter operators when single-split ventilation is utilized, (2) a statistically significant relationship be­tween quartz content in face material and operator exposure was not determined and data suggested mining equipment and procedures may be more critical. The Phase III lab tests indicated the use of dust hog-type bits, filter cartridges, maximized collector airflow, and reduced bit rpm should be utilized to minimize dust liberation at the roof bolter.

Jan 1, 1985

By Juan Oswaldo Alfaro, Angel C. Nuñez, Hildebrando A. Cóndor

Se ha desarrollado un software para facilitar la evaluación del proceso molienda-clasificación en plantas concentradoras. Se ha modelado en UML-Lenguaje Unificado de Modelado; los datos e información se almacenó en SQL Server; se programó en Java (Programación Orientada a Objetos). Investigación Aplicada y Cuantitativa obteniendo como resultados un Software para Circuito de Molienda-Clasificación (Directa e Integral).

Sep 1, 2017

As a result of early experiments in underground mine illumination, the Bureau of Hines recognized the need for additional experience with the underground lighting of coal mines having low seam thicknesses. There was already experience with tile illumination of coal mines having higher coal seams, and this contract with Ocean Energy Inc. (OEI) was undertaken to contribute to the "low coal" experience. For the purpose of this contract, a "low coal? mine is defined as one having less than 45 inches of overall headroom in the working places. As a practical limit, 26 inches was the minimum coal seam thickness to be encountered in this program. In one instance, the maximum coal seam thickness was eight to ten feet, however, this particular work was at the direction of the Technical Project Officer (TPO) by virtue of the unique type of lighting arrangement that was to be evaluated which would be useful for low coal. At the outset of the contract, three major tasks were established. The first two tasks involved the installation of permissible fluorescent lighting equipment at two low coal mines. The intention was to illuminate mining sections in each case consisting of one or more machines. The third task was to illuminate a variety or mining equipment including a longwall. For the purpose of this report, the fol-owing identifies the particular installations associated with each task.

Jan 1, 1976

By E. J. (Kirk) Conway

Thirty-five years ago underground coal mining equipment consisted of simple but rugged machines powered by electric motors and hydraulics. The machines were maintained by maintenance personnel armed with a basic knowledge of hydraulics, electricity, and mechanical design. Over the years the the machine has been transformed into powerful complex mining systems. The maintenance burden has also increased. During this period significant advances have been made in maintainability engineering and system design techniques. Many of these innovations and techniques are applicable to the design of underground mining equipment. The objectives of this project were to; (1) determine the extent to which maintainability design concepts and principles have been applied to the design of underground coal mining equipment, (2) try to assess the impact of equipment design for maintenance on productivity and safety, and (3) develop a maintainability design guideline to enhance the design of new or rebuilt equipment. An equipment design review was completed at ten operational coal mines. Interviews were also conducted with mine management, safety, and maintenance personnel to identify machine specific design advantages and problems. Visits were also made to six original equipment manufacturers to discuss the design of their equipment for maintenance. Volume I presents an overview of the protocol used and a summary of the findings. Volume II includes the maintainability design guide for underground mobile mining equipment.

Jan 1, 1989

By F. W. Clark

At the present time, when lixiviation versus amalgamation is being so thoroughly discussed by practical men, and published information is so meagre, the following tests, made by students in the mining laboratory of the Massachusetts Institute of Technology, may be of interest to others. The ore experimented upon was obtained from the Sombrerete mines near Zacatecas, Mexico. A careful analysis of the dried sample resulted as follows : Per cent. SiO2,............62.79 S.............13.86 Al2O3............4.39 Fe,............11.26 Zn,............1.57 CaO.............2.91 MgO,........... 0.06 Cu,.............0.12 Pb,.............0.40 Sb and As,..........trace CO2,............2.35 Ag,.............0.16 99.87

Jan 1, 1886

By P. J. Brereton-Stiles, C. J. Hockaday, I. J. Barker, M. S. Rennie

This paper reports on studies that have been done on the electrical conduction in silicon, ferro silicon, and charge chrome furnaces. A system has been developed that can distinguish between normal resistive conduction and arcing, and this was used to quantify in particular the relative amount of arcing that takes place in these furnaces. It was found that silicon and ferro silicon behave similarly and exhibit a relatively large amount of arcing. Charge chrome on the other hand exhibits considerably less arcing, and the extent of this arcing is highly correlated with the tapping of the furnace. The arcing measurements can also be used online in the control of the furnace, both for the electrodes and electrical circuit, and for the raw materials.

Jan 1, 2007

By John T. Whetton

"FROM 1850 when the annual production was around 50 million tons, coal output in Great Britain expanded rapidly to 225 million tons in 1900 and 287 million tons in 1913. However, during the First World War, countries which had previously bought large quantities of coal from Britain sought other sources of sup-ply or developed their own coal re-sources. Thus from the record figure of 73 million tons exported in 1913, Britain's coal exports declined until in 1938 they stood at 39 mil-lion tons. An important reason for this was the development of oil engines for marine propulsion. Today, nearly all the navies and mercantile shipping in the world have turned to oil engines. Sometime in the future, however, it is reasonable to expect nuclear power to replace oil.During the Second World War, coal output in Great Britain and manpower at the mines were reduced considerably and in 1.945, 175 mil-lion tons were produced by 709,000 miners. Exports were meagre, only 8.""7 million tons went to foreign consumption. During the severe winter of 1947, inland demand for coal exceeded production and exports were prohibited. Even importation of coal was required to meet inland demand. These were years when the coal industry of Great Britain made immense efforts to secure maximum output irrespective of economy. The energy needs of Great Britain appeared insatiable; but had it been possible to export, the nationalised mining industry could have made huge profits as there was a world shortage of coal. However, home needs were considered to be the priority and many overseas markets were lost. Other producers moved in and secured long-term contracts. Not only was the British export market lost, but also the nationalised industry had to sell the imported coal at the same prices as home-produced coal and suffered losses up to of:3 per ton. Bence, at a time when the National Coal Board might have ac-cumulated a reserve fund to cope with less prosperons times, it was having to spend large sums of money securing sufficient coal for inland consumption. This was a time when intensive efforts in the mining industry, comparable with those of many industries and establishments inclusive of the armed services during the war, would have produced a greater amount of coal and have been of immense value to the country as a whole."

Jan 1, 1960

By Robert Jakiel

The following paper is being presented to provide a basic understanding of the equipment and procedures used in multi-auger deep soil mixing as part of the program for the Deep Foundations Institute (DFI) Deep Soil Mix Seminar. The paper is written as a summary of the author's experience using multi-auger deep soil mixing equipment while working with SMW Seiko, Inc. on several east coast projects in the United States, particularly the soil-cement mixing for the soil stabilization of the Fort Point Channel area in Boston, Massachusetts, one of the largest and most difficult soil mixing projects completed thus far in the United States. The summary provides a brief summary and insight into some of the operational aspects of the equipment and procedures, and some of the important considerations when using multi-auger deep soil mixing. This paper is intended for use by both the contractor and the designer involved in selecting appropriate soil mixing equipment and procedures for various types of soils, depths or applications, or for a better understanding of the operational aspects, potential benefits, and impacts that the performance criteria may have on the operational capabilities of the soil mix equipment, when specifying multi-auger soil mixing for a particular project. Prior to reading this article it is important to become more familiar with the various acronyms and terminology used in soil mixing technology. A Definitions section has been provided at the end of the paper that will help the reader become more familiar with some of the terms used throughout this paper.

Jan 1, 2001