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By Janet Torma-Krajewski, Pauline Lewis, Paul Gust, Lisa Steiner, Kean Johnson

Since 1990 and the publication of the Ergonomics Program Management Guidelines for Meatpacking Plants by the US Occupational Safety and Health Administration, numerous reports of companies implementing ergonomics program have been published. However, despite these numerous reports, no examples of implementing an ergonomics program in the mining industry have been reported. In 2000, NIOSH initiated a long-term project to demonstrate the implementation of an ergonomics process designed to identify and reduce exposures to ergonomic risk factors found in mining. The mine selected for this project was the Jim Bridger Mine, a surface coal mine located 35 miles northeast of Rock Springs, Sweetwater County, WY. This paper discusses how a large, surface coal mine implemented an ergonomics program and the lessons learned while doing so.

By L. M. Chan, D. H. Carlson, J. H. Johnson

"This paper discusses the evaluation and application of a portable parked-vehicle tailpipe emissions measurement apparatus (EMA). The EMA consists of an exhaust dilution system and a portable instrument package. The EMA instantaneously dilutes and cools a sample of exhaust with compressed nitrogen or air at a known dilution ratio, thereby presenting it to instruments as it is presented to personnel in the surrounding environment. The operating principles and governing equations of the EMA are presented.A computational method is presented to determine the engine operating and performance parameters from the exhaust CO2 concentrations along with an assumed engine overall volumetric efficiency and brake specific fuel consumption. The parameters determined are fuel / air ratio, mass flow rates of fuel, air and exhaust emissions, and engine brake torque and horsepower. These calculated engine parameters are used to characterize engine load when performing EMA in-field tailpipe sampling without a dynamometer, and to detect deteriorated engines.Evaluations of the EMA by comparison of diesel tailpipe measurements with those made using laboratory-grade instruments showed that the EMA measurements are accurate and reproducible. The results also show that the EMA is capable of detecting emission concentration changes resulting from engine faults. Calculated engine operating and performance parameters correlate and compare well with laboratory-measured values.The EMA in-field engine loading and tailpipe sampling procedures for parked vehicles are presented, and results of the EMA field measurements are also presented. Low coefficients of variation for repeat EMA tailpipe measurements on diesel-powered haulage vehicles in four underground mines indicate that the EMA in-field engine loading and tailpipe sampling procedures are reproducible.An analysis of EMA tailpipe measurements for three haulage vehicles in one mine shows that the EMA can: 1) identify haulage vehicles that emit excessively high pollutant concentrations, and 2) provide data needed to evaluate and determine the efficiency and effectiveness of tailpipe emission control devices.Finally, recommendations for a proposed commercial EMA system are presented. This commercial system would overcome many of the adverse features of the prototype EMA used in these tests."

Mar 1, 1992

By Willard L. Hunter

The research described in this Bureau of Minus report was conducted to improve the chromium-iron ratio of offgrade chromite. Two methods were used: (1) Iron was selectively reduced from chromite by carbothermic reduction in an electric-arc furnace, and (2) a mixture of carbon, chromite, and sometimes fluorspar was chlorinated to remove a substantial part of the iron. Chromite concentrate from the Mouat deposit in Montana and from northern California was used in the test work. Chromium-bearing slag and chromite that had been beneficiated by a roast-leach process were each smelted to produce high-carbon ferrochromium. Iron was selectively reduced in a laboratory-scale., electric-arc furnace. Carbon additions to the smelting charges varied from 40 to 100 percent of the stoichiometric requirement, and slag basicities were varied from 0.4 to 1.0 chromium-iron ratios of more than 4:1 were obtained with 89 percent recovery of chromium in a chromium-bearing slag.

Jan 1, 1962

By David D. Rabb

A report on location, sampling, assays, mineral examination, amenability leach tests, and evaluation of certain mine dumps in Mohave County, Arizona. Extractions of greater than 30 percent of the gold and silver were achieved during simulated heap leaching of selected mine dump material. Consumption of reagents was relatively low and results suggest leaching of prepared heaps is technically viable and could be economically attractive.

Jan 1, 1980

By W. W. Adams, V. E. Wrenn

"Production of explosives in the United States during the calendar year 1935 decreased 2 percent from 1934, according to reports covering all companies engaged in the manufacture of explosives during those years.Reports from manufacturers showed a total production of 308,381,250 pounds of explosives; this quantity included 39,170,016 pounds of permissible explosives 5/ 200,323,559 pounds of high explosives other than permissibles, and 68,887,675 pounds of black blasting powder of which 34,222,625 pounds were granular powder and 34,665,050 pounds pellet powder.Coal mines consumed 89 percent of the total production of blasting powder, 99 percent of the total output of permissible explosives, and 11 percent of the output of other high explosives.The metal mines of the United States used 28 percent of all high explosives other than permissloles, less than 1 percent of all permissibles, and 1 percent of all black powder produced.Quarries and nonmetallic-mineral mines consumed 17 percent of the high explosives other than pormissibles, less than 1 percent of the permissible., and 3 percent of the blasting powder.Construction work required the largest quantity, 40 percent of all high explosives manufactured during the year. Less than 1 percent of the permissibles and 6 percent of the black powder produced during 1935 was used in construction work."

Nov 1, 1936

By H. C. Ko

As part of the Bureau of Mines effort to provide thermodynamic data for the advancement of mineral technology, the standard enthalpies of formation for ZnO?2ZnSO4 and COS04-6H20 were determined by HC1 acid solution calorimetry. The values are -550.31 ±0.28 and -641.33 ±0.15 kcal/mot, respectively.

Jan 1, 1982

By L. A. Haas

S02 reduction with CO was studied in an integral flow reactor at a nominal flow of 0.5 liter per minute. Reactant gas contained 3 percent SO2, 6 percent CO, and the balance He. SO2 conversion was determined for three different types of catalysts. The first consisted of 16 commercial catalysts used for various chemical syntheses. Only the commercial catalysts which contained transition metals in alumina removed more than 30 percent 80a at temperatures below 510° C. Two other types of catalysts were prepared in the laboratory either by pelletizing equal amounts of powdered alumina and transition metal oxides or by impregnating commercial alumina tablets with transition metal ions. Regardless of preparation techniques, Cr and Fe in alumina were the two best catalysts. The observed results suggest that an intermediate (SCO) is formed by the interaction of surface metal sulfides and carbonyls. Alumina then catalyzes the interaction of SCO with S02 to form the end products (sulfur and carbon dioxide). Over 80 percent S02 was removed at 460° C with 2 grams alumina impregnated with 2.5 percent iron.

Jan 1, 1972

By H. Stuart Auvil

Twelve samples of run-of-oven coke were taken at coke plants in the United States and Canada. Sampling procedure was directed toward obtaining the highest possible degree of uniformity in the gross samples, so that variations in results caused by sampling variations were at a practical minimum. Under these conditions the standard deviation of the screen analysis test on 500-pound samples is found to range from 1.2 percent for the 1-inch screen to 4.5 percent for the 5-inch screen. At present, the A.S.T.H. standard method of test requires that results be reported to the nearest 0.1 percent. This implies a higher than actual degree of precision, and revision of the report required by the method is suggested. Much larger Samples than are generally tested are required to reduce normal testing errors to a point where they are not appreciable fractions of the total variations found in a smoothly operating plant. For example, it is deduced that over 100,000 pounds of coke must be screened to determine if ordinary day-to-day variations in screen analysis have appreciable effects on the performance of a blast furnace.

Jan 1, 1950

By William A. Beck

The K.T. Dome Mine in Owen and Henry Counties, Ky., has been operated intermittently under several different owners since the early nineteen hundreds. No record of total production is available, but it is said that during 1943 and 1944, while being operated by the Twin Valley Mining Co., 30 cars of zinc concentrates and 10 cars of lead concentrates were shipped. The vein can be traced for about 10 miles along the strike from Lockport, Henry County, to Big Twin Creek in Owen County. It pinches and swells both vertically and horizontally and is reported to average 20 inches in width. In order to develop additional reserves on the property, the Bureau of Mines drilled four holes on the south extension of the vein. Drilling disclosed that the vein dips to the west on the south side of the Kentucky River and is continuous along the strike and in depth. However, the extent of mineralization in the vein varies widely.

Jan 1, 1949

By Charles B. Carpenter

When a drilling well strikes a horizon in which there is a large volume of petroleum or natural gas under high pressure, danger of a blowout with disastrous results is imminent unless proper precautionary measures are taken. The history of oil-swell drilling has been marked by many blow-outs and wild wells, some of which-have caught fire and burned for long periods. Such incidents nearly always make headline news, but ordinarily few persons realize that what to them is an interesting newspaper item may entail great financial loss to the operator and frequently loss of life or personal injury to members of the drilling crew and others in the vicinity of the well. The blow-out, wild well, and crater are dreaded specters to every thoughtful person in the oil industry because of danger to life and property, underground damage to surrounding wells, dissipation of reservoir energy, and waste of irreplaceable natural resources that blow to the air or migrate to barren formations. Every operator drilling in high-pressure fields must be on the alert always to forestall any conditions that may lead to a blow-out, and his vigilance must not cease until a well is completed and oil, gas, or both are flowing to storage or market.

Jan 1, 1937

By Charles Findlay, Stephen Krickovic

A methane emission rate study was conducted in 1969 on a longwall section of a Lower Kittanning coalbed mine in central Pennsylvania. The longwall face was mined with a drum shearer between developed headings on the head end and headings on the tail end that were driven with a ripper-type continuous miner as needed. The study was conducted over 22 consecutive shifts (7-1/3 days). The average methane emission rate from the Lower Kittanning coalbed during mining at the face and developing the headings at the tail end of the face was 34 cfm. Caving of the gassy overlying strata as the result of mining at the face increased the methane emission to rates ranging from 702 to 1,049 cfm.

Jan 1, 1971

By Ann C. Kim

This Bureau of Mines report summarizes the methods and results of many of the laboratory studies on spontaneous heating of coal published in the last 50 years. It includes a brief description of experimental methods, indices of combustibility, and important contributing factors. Adiabatic calorimetry, isothermal calorimetry, [0], sorption systems, or temperature differential are the most frequently used experimental methods. Indices of combustibility include various heating rates, crossing point temperature, ignition temperature, and CO index. Factors that affect the spontaneous heating of coal include air flow rate, changes in moisture content, particle size, rank, temperature, pyrite content, geological factors, and mining practice. Experimental conditions and results from 20 papers are summarized in an appendix, and the bibliography contains 45 references.

Jan 1, 1977

By E. L. Garton

The Bureau of Mines for a number of years bas been conducting an investigation of crude petroleum from producing fields in the United States and the Western Hemisphere and has published a series of reports on these fields. Analyses of crude-oil samples from many oil fields of Oklahoma are given in Bulletin 2915. Analyses of 21 representative crude oils from various producing zones of the Oklahoma City field are given in this report. A close study of the analyses reveals very few differences in the general characteristics and chemical properties of these oils.

Jan 1, 1932

By Catharine T. Fogg

The U.S. Bureau of Mines investigated the availability of platinum, palladium, and rhodium from 16 deposits in four market economy countries (MEC's). Major recoverable products include 164 Moz of platinum, 80 Moz of palladium, 13 Moz of rhodium, 24 Moz of ruthenium, 4 Moz of Iridium, 2 Moz of Osmium, and 10 Moz of gold. The 12 deposits in the Republic of South Africa are estimated to account for 96.7 pct of total recoverable platinum. The base-case scenario estimates the long-term cost of production including recovery of capital, but provides no return on the investment or O-pct discounted cash-flow rate of return (DCFROR). The total production costs in January 1990 U.S. dollars ranged from $325/oz to $1,288/oz of platinum compared to an average January 1990 price of $492/oz. Approximately 83 pct of total recoverable platinum was economic at a cost level of $4S0/oz or less. At the IS-pct DCFROR, only 26 pct of total recoverable platinum was economic. For platinum-group metals (PGM), attention has been focused on the ratios of the three primary metals: platinum, palladium, and rhodium. Sensitivity analyses were performed to determine the impact long-term rhodium price increases could have on the total cost of production for platinum and palladium.

Jan 1, 1993

By W. T. Westbrook

This Bureau of Mines report contains methods for analyzing iron are for total iron, ferrous iron, metallic iron, silica, manganese, aluminum, calcium, magnesium, phosphorus, titanium, carbon, sulfur, moisture loss, and ignition loss by wet chemical methods. Some are modifications of standard umpire methods; others have been developed by the Bureau of Mines to provide a com-bination of speed and accuracy. They are suitable for a high volume of samples and/or control situations, and for situations in which instrumental results must be verified. These methods have been used to analyze taconites, native ores, some foreign ores, and metallurgical products.

Jan 1, 1975

"It is evident that the incidence of coal worker's pneumoconiosis (CWP) or black lung disease varies in different coal producing regions of the United States. Many people have hypothesized about the reasons for the differing occurrences. Because underground coal mining involves many mining methods under changing geological conditions, several factors may be involved in contracting CWP such as: the amount of quartz in the respirable dust, the trace elements in the respirable dust, the rank of the coal that produced the respirable dust (bituminous, anthracite), the amount and size of respirable dust, etc.Recognizing the uniqueness of underground coal mining and CWP, research investigations involving seam characteristics, mining system and worker position are being conducted in the center to establish standard procedures for characterizing some coal properties that may be involved in workers contracting CWP. This has been accomplished by the in-mine sampling of airborne dust at various worker locations and mining system configuration and by performing laboratory analyses of mined material (coal and rock) taken from the mines. (FIGURE 49 and 50)The investigations includes a method of classifying coal seams according to their potential to generate respirable dust. It includes statistical analyses of the size and locational variations of the elemental compositions of respirable coal mine dust in operating underground mines from seams located in the eastern, midwestern, and western United States, and is currently completing research which is investigating the relationship between the elemental compositions of respirable dust sampled near a continuous-mining machine and a laboratory-produced respirable dust."

Nov 1, 1988

By Sabri Ergun

This report gives the result of investigations of coals of different rank, coal com¬ponents, chemically and thermally treated and irradiated coals, and sedimented organic matter. In most studies the arbitrary parameters obtained from the usual quantitative profile analyses are not given largely because they lack physical meaning. Instead comp interpretations are offered. X-ray patterns of high-volatile bituminous and lower rank coals are not self¬-sufficient for structural interpretation by the methods of analysis developed to date. The patterns of hydrogenated and dehydrogenated coals indicate that the basic change in the structure of bituminous coals with increase in rank is the conversion of alicyclic structures into aromatic layers. In low-rank anthracites the aromatic layers are about 10 A in size. The increase in rank is the result of coalescence of layers. High-rank anthracites have layer sizes of 25 to 40 A and exhibit the development of three-dimensional (hkl) reflections of graphite, indicating ordering of adjacent layers. In meta-anthracites the layers are > 1000 A and the basic structure is that of defective crystalline graphite. The well-known petrographic components in low-rank coals have different structures; the differences dissappear in low-volatile bituminous and higher rank coals. The patterns of sedimented organic matter, except impsonites, differ from those of coal hydrogen contents are high, and their X-ray patterns are consistent with those of structures. In contrast to normal coals, the patterns of uranium-bearing coals show increased diffuseness with decrease in hydrogen content. The diffuseness is accompanied by increase in the uranium content of the coal. It is very likely that high uranium-bearing coals have predominantly tetrahedral structures.

Jan 1, 1968

By J. R. Thoenen

[For several years the Bureau of Mines conducted tests on ground vibration t emanating from quarry blasting in an effort to determine an index of destruction for different types of structures. Results of these studies have been published in four Bureau of Mines Reports of Invitations as well as in several articles in the trade and technical press.5/ The first paper (3)6/ discussed the subject in general and gave results s of a few blasting records. Some tentative theories also were advanced. The second paper (4) discussed results s of records made from blasting in a number of quarries.]

Jan 1, 1940

By F. D. DeVaney

Metallurgists and coal-washing engineers have used heavy liquids for years in studying the characteristics of ores and coal. By such means true separations can be made between the various specific-gravity increments in the materials examined. To use of heavy liquids has permitted determination of the possible grades of tailings and concentrates by specific-gravity methods on any particular size, and therefore the size to which the ore must be crushed to free the valuable material. The simplicity of float-and-sink separation and the high degree of efficiency attained in the laboratory are factors that commend the method for commercial concentrations.

Jan 1, 1940

By F. D. DeVaney

The low-grade deposits of manganese ores along the Missouri River near Chamberlain, S. Dak., are known to contain one of the largest reserves of manganese in the United States. Manganese occurs as concretionary nodules ranging in size from 13 inches in their longest dimension to particles finer than 65-mesh. The nodules are embedded in soft, wet shale, which contains little manganese. The removal of nodules from the low-grade shale is a simple mechanical problem; the question is primarily to determine the lowest-cost method of separation. This report purposes to present data acquired by experimenting with samples of the ore, which form a basis for suggesting methods of concentrating manganese nodules.

Jan 1, 1942