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By R. H. Storch

The work described in this report was part of a Bureau of Mines program to appraise the titanium-mineral resources of Idaho. Part of the program included churn drilling of alluvial deposits that previous preliminary testing, primarily for rare minerals, had indicated to be potential sources of titanium minerals. The first spot churn drilling began in the Deadwood placer area, Valley County, Idaho, in July 1956 to determine both the amount and grade of the ilmenite, FeTi03. Ten holes, ranging in depth from 6 to 40 feet and aggregating 251 feet, were drilled; 54 samples were taken. The samples were sent to the Spokane field laboratory for concentration and visual estimation of the amounts of the more common minerals in the heavy sand concentrates. For specific determinations samples from each drill hole were composited and shipped to the Bureau of Mines laboratory in Albany, Oreg., where petrographic, quantitative X-ray spectrographic, and chemical analyses were made.

Jan 1, 1958

By Louis A. Panek

Tests of mine-roof models in a centrifuge show that the suspension effect due to bolting a horizontally bedded mine roof with frictionless surfaces of contact between beds depends principally on the number of bolted beds and their relative flexural rigidities, provided that sufficient bolt tension is exerted to prevent strata separations at the bolt locations. Strata separations tend to occur in the unbolted roof mainly because the beds have unequal thicknesses. "Suspension effect" refers to the transfer of part of the weight of weaker or thinner beds to the flexurally more rigid beds by roof bolts or by any other means. The factors investigated were number of beds in the bolted unit, bed thickness, modulus of elasticity of beds, length of bolts, spacing of bolts across and along the opening, bolt load, and intensity of roof load. The general principles of behavior of the bolted roof beds are explained by an approximate theory. Model test data are used to validate the theory and to obtain an expression for the "suspension efficiency". As the suspension effect actually observed in the models is smaller than that predicted by the approximate theory, the suspension efficiency in general is less than unity. Mathematical expressions are obtained for (1) the change in roof bending stress due to the suspension effect, which is needed for design of a roof-bolting system, (2) the change of roof deflection due to the suspension effect, which may be useful for evaluating the effectiveness of a roof-bolting system, and (3) the bolt load or pre-load that is required to achieve the desired reinforcing effect.

Jan 1, 1962

Develop a means for estimating vertical stress conditions in or around an underground mine so that appropriate measures for ground control can be taken before hazardous conditions arise. Background High vertical stress in an underground mine could cause or enhance hazardous ground control conditions which might lead to accidents, fatalities, and loss of reserves. An understanding of the vertical stress conditions at the mining level would allow a mine operator to take precautions that will minimize the occurrence of ground control problems. A knowledge of the underground stress conditions prior to mining could be used as an aid in future mine plan development to avoid or minimize ground control problems. Approach The Bureau of Mines developed a computer program for calculating the vertical stress resulting from the pressure of overlying rock masses on a mine or geologic surface at various depths.

Jan 1, 1990

By M. A. Lucas

The Bureau of Mines has developed a computerized mathematical model to predict the distribution of accessory elements throughout a metallurgical process. The model can be used to determine process conditions that effect better accessory element control consistent with continued high primary metal recovery. The model presented is specific for determining the bismuth distribution in lead smelting but can be adapted to most extractive metallurgical processes. Thermodynamic, kinetic, and process parameters form the base for the model. Its logic and structure are described in detail.

Jan 1, 1983

By D. E. Emerson, C. G. Kirkland, E. M. Frost

An apparatus has been developed for determining the helium content of gases containing 40 percent or more helium . It utilizes activated coconut charcoal at liquid nitrogen temperatures to adsorb constituents other than helium in the mixture . Series of analyses have been run where the mean deviation was less than 0.05 percent helium . Twenty or more analyses can be made in an 8- hour day .

Jan 1, 1964

By R. E. Hall

When the criterion for control of scale prevention on the evaporating surfaces is made the conditions in the concentrated boiler water, then this control becomes an exact operation amenable to an accuracy commensurate with all other operations in the boiler room. The responsibility in boiler water conditioning, however, includes more than clean surfaces. Corrosion in feed lines, economizers and the boiler is a function of the condition of the later, and must be controlled. Steam line and turbine blading deposits must be obviated by the system of conditioning. By the chemical treatment employed, the amount and character of noncondensable uses in the steam must be controlled in accordance with the intended use of the steam. All. in all, the responsibility in boiler crater conditioning ends not with the entrance of the water into the boiler but with the passage from the boiler nozzle of steam, the dryness and rarity of which are defined by the uses to be made thereof. A clearer conception of the scope of boiler water conditioning can be obtained by reference to a diagram of the surfaces (Figure 1) at which it functions. Consideration of this diagram leads to the following outline for the problems of boiler water conditioning: (a) Prevention of scale formation on surfaces (1) In contact with water but at which no evaporation occurs. (2) At which evaporation is occurring.

Jan 1, 1926

By Thomas J. Peters

The U.S. Bureau of Mines studied the 63,9SS-acre Hanson Lakes study area, including the Ten Mile-East and part of the Ten-Mile West RARE II areas, plus additional acreage, all proposed at times for Wilderness designation. The study was part of a Idaho Land Assessment Program with the Idaho Geological Survey and the U.S. Geological Survey, to provide minerals information for land-use decisions, and ensure domestic mineral supplies. The area is at the north end of the rugged Sawtooth Range and includes parts of the Sawtooth National Recreation Area which is closed to mineral location. The Copper Mountain. Elk Mountain, and Observation Peak mineralized areas are in the study area, but only Copper Mountain is open to claim location. It is on the trans-Challis fault zone and contains Tertiary granite which is favorable for mineral deposits of gold, beryllium, niobium, REE (rare-earth elements), tin, molybdenum, copper, silver, and lead. Identified resources are 1.9 million tons of flake graphite at Elk Mountain, but much more graphite occurs in the vicinity REE occurs in 18 black sand placer sites along the lower reaches of study area streams just outside the study area, on Cape Horn Creek, Marsh Creek, and lower Valley Creek flood plains, and at one hydrothermal site near Observation Peak. Hydrothermal REE is commonly low in? by-product thorium. a radioactive disposal problem. Many advanced REE applications enhance the quality of life, and future uses in superconductivity may reduce energy consumption. Seventeen lode, one geothermal, and 11 placer prospects were examined. Workings totaled about 20 adits, one shaft, several open cuts, and numerous small pits. Approximately 500 mining claims have been located or relocated in the study area, including a 200-claim block for disseminated molybdenum.

Jan 1, 1992

By A. J. Kraemer

For a number of years the Bureau of Mines has conducted semi-annual survey to determine the changes in the characteristics of the rotor gasoline being sold in the United States. Certain cities have been decided upon as points of origin of samples. Tare choice of these cities has been governed by their situation as the representative of a more or less definitely bounded marketing territory. Samples have been taken on or about the fifteenth day of January and July of each year. In the collection of the samples an attempt has been made to get a representation of the important types of motor fuel being sold, and also to tame into consideration the proportion of tie total consumption that is supplied by the different marketers. It is therefore felt that the survey affords a reliable indication of the quality of the gasoline being sold throughout the United States at the time of sampling. The figures in Table I, below, were obtained by averaging the end points of the least volatile and most volatile samples of gasoline. For example, of 850 samples analyzed in 1919, the 10 per cent (85 samples) having the highest end points, and the 1C per cent having the lowest end points were averaged. These averages are represented in the table as the "Maximum 10 per cent" and the "Minimum 10 per cent", respectively. The same scheme was used in the succeeding surveys.

Jan 1, 1925

By H. E. Powell

Over 5 million lb of chromium, 1 million lb of nickel, and 90,000 lb of molybdenum are lost annually in the dusts generated in the production of stain-less steel. Additional losses of these metals in the form of mill scale and grinding swarf may be double the dust losses. This Bureau of Mines report describes a process for recovering these and other metals in the form of an alloy steel suitable for recycling. Zinc and lead, when present in the wastes, are recovered as byproducts in the form of oxide fumes. The laboratory-scale process (10-to 25-lb charges) recovers up to 95 pct of the chromium, 100 pct of the nickel, and 100 pct of the iron. The resultant alloy contains from 10 to 20 pct chromium, 6 to 12 pct nickel, and 55 to 65 pct iron, with lesser amounts of molybdenum and manganese. The alloy is essentially free of zinc, lead, and sulfur. The zinc-lead fume obtained from the treatment contains about 40 pct zinc and 20 pct lead and represents essentially complete recovery of these metals.

Jan 1, 1975

By Kyei-Sing Kwong

The U.S. Bureau of Mines investigated the synthesis of advanced ceramics (SiC+AlN, SiAlON, SiC+A1203, and Si3N4+AlN) from natural clays (kaolin, halloysite, or montmorillonite) by an intercalation and heat treatment method. This process includes the steps of refining a clay, intercalating organic chemicals into its layered structure, drying the intercalated mixture, firing the treated structure at certain temperature ranges in controlled atmospheres to form desired compounds, and grinding the loosely agglomerated structure. Focus of this research is to economically process advanced ceramic structures from abundant natural resources. The advanced ceramic phases produced in this simple treatment are homogeneously distributed at the nanostructure level, and may potentially lead to cost effective manufacturing processes. The intercalation of clay was confirmed by X-ray and BET analyses. The evolution of chemical compositions during carbonization reactions and carbothermal reduction was investigated. The characteristics of refined clays and synthesized powders were studied. Advanced ceramic composites/solid solution have been produced from intercalated clays, without the presence of other compounds.

Jan 1, 2010

To improve safety by making speed and direction control of a tracked vehicle simpler and instinctive. Approach A joystick control (which determines vehicle speed and direction of movement as well as the direction of any turning or pivoting) was developed and tested on a loading machine during a long-term underground demonstration. How It Works The control box actuated by the joystick lever contains two multiposition, multideck rotary switches. Fore-aft movement of the joystick rotates one switch through five positions to provide a neutral position and two speeds of travel in both

Jan 1, 1978

By D. A. Doughty

The Bureau of Mines developed two methods for determining iron II and iron III in 2- to 5-mg samples of coal using electron paramagnetic resonance (EPR) spectrometry. One method used solid coal samples; the other method used aqueous solutions. The method using solid samples was more simple, technically, but required the use of X-ray fluorescent analysis, or another independent method, for determining total iron in the samples, and the results were subject to some uncertainty. The method using aqueous solutions appeared capable of greater certainty and did not require additional methods of total iron analysis but was more involved procedurally. The coals analyzed were found to contain much more iron II than iron III.

Jan 1, 1973

By Steven R. Davis

Dear Interested Party: Subject: Notice of Intent to Solicit Outside Opinions Regarding Amendments to the Rules Concerning the Leasing of State Owned Lands for the Mining of Metallic Minerals The Department of Natural Resources, Division of Minerals, is seeking outside opinions concerning the leasing of state owned lands far the mining of metallic minerals. Enclosed for your information in a copy of the Notice of Intent to Solicit Outside Opinions Regarding Amendments to the Rules Concerning the Leasing of State Owned Lands for the Mining of Metallic Minerals.

Jan 1, 1994

By Manuel Gomez

The mean and the standard deviation were used to describe general sulfur and ash populations as well as specific populations of these variables from one coal seam. Both the mean and the standard deviation were incorporated in the exploration process to determine the number of drill cores necessary for seam evaluation and to guide the sequential drilling plan. Probability regions were computed to establish a basis for predicting probable ranges of average sulfur and ash concentrations that may be expected upon continued or future drilling. A computerized plot program was utilized to interpolate sulfur and ash concentrations between grid points. The plot program, which is essentially a moving average technique, permits a rapid evaluation of sulfur, sulfur forms, and ash spatial distributions as a drilling program progresses sequentially. This information, in the form of contour plots, can be made available to both the mining engineer and the fuel technologist in advance of mining to outline reserves, to improve selective mining, and to anticipate preparation facilities.

Jan 1, 1972

By L. G. Austin

"This paper is based on the development of the Maza-Austin technique for characterizing thousands of coal particles by approximate analysis of the major inorganic constituents Ca, Al, Si, K, Na, Fe and S in each particle. The technique has sufficient sensitivity to work on small volumes, is fast enough to handle large number of particles within a reasonable period of time, and consists of scanning electron microscopy combined with energy dispersive x-ray spectrometry (SEK-EDS). A computerized SEK-EDS system that allows the automated analysis of hundreds of coal particles per hour' is described. The analysis is based on the location and tracing of coal particles embedded in a polished specimen, the selection of sampling points on the traced particles, the collection of an x-ray spectrum from each sampled point for a defined period of time, and the processing of the x-ray intensity to calculate point composition using ZAF corrections. Procedures for correcting for dead time, background, detector efficiency and spectrum overlap are described. These corrections are essential if reasonably accurate analyses are to be obtained from unknown complex mixtures of the elements in a coal or fly ash particle. Examples are given. INTRODUCTION Coal is a complex mixture of organic and inorganic materials. The inorganic fraction is referred to as mineral matter (Gluskoter, 1978) but can occur in three modes: (i) an observable mineral species; (ii) as cations held by ion exchange to carboxylic groups; and (iii) in chelate complexes. The mineral matter content normally represents a significant proportion of a coal, with an average value of about 15% for US coals (Gluskoter, 1975). The standard methods of analysis of the mineral matter in coals are performed on a sample selected to represent the whole coal as closely as possible, and give the overall inorganic composition in the coal. Such analyses are of limited use for solving problems originating from the behavior of individual coal particles, whose compositions vary widely from the average value. This is particularly true in pulverized coal combustion, where the current methods of predicting the slagging and ·fouling potential of a coal are based on the bulk ash composition, but the fly ash particles which create the deposits originate from coal particles with large differences in mineral compo1ition. Some examples can be found where, in a comparison between two coals, the one with the smaller slagging potential according to the mean ash composition was the one that behaved worst in the furnace (Moza et al., 1980; Koza and Austin, 1983). The u1e of gravity fractionation to assess the slagging potential of pulverized coals has shown that conventional ASTM analysis is not sensitive to differences in the distribution of mineral matter when comparing coals (Borio and Narciso, 1979). Bryer (1979) concluded that coals should be examined for fouling and slagging potential by analyzing gravimetric and size-fractionated coal, preferably pulverized· and ground to the size expected at the mill outlet."

Jan 1, 1989

By W. J. Wenger

Analytical, geographical, and geological data on 67 samples of crude oils from Utah are presented, along with some correlations and interpretations. Most of the, geologic formations that produce oil in other areas are also productive in Utah; and as in many other locations, the Permian, Pennsylvanian, and Mississippian formations account for the major amount of the total oil produced in the State. Some anomalies and unusual phenomena are noted. Although most Utah oils are low in sulfur, a sample containing the highest percentage of sulfur ever recorded by the Bureau of Mines is among the oils discussed in this paper. Most of the oil from the major producing formations in Utah is low in sulfur; the same formations produce high-sulfur oils in adjoining Rocky Mountain States. Some Utah oils are both waxy and asphaltic, an unusual combination of characteristics. Correlation index curves for some oils are shown suggesting compositional differences in oils from different producing formations. Production statistics trace the rapid rise of oil production in the State after the first commercial discovery in 1947 and indicate a decline in amounts produced since 1959, the year of peak production in Utah.

Jan 1, 1971

By W. M. Myers

Water has been commonly used as a collecting medium in many instruments employed in the sampling of dusty atmospheres in mines** add industrial plants, and for this purpose has much to recommend it, particularly the following factors:1.,Water is a very efficient dust collector.2.,Distilled water of great purity may be readily obtained at slight expense. The analytical error introduced by the extremely small amount of foreign matter in carefully distilled water is very small,3.,Water is a very convenient medium with which to work as all the analytical operations of diluting, aliquoting, and filtering are readily and speedily carried out. Water has therefore been used extensively in such instruments as the Palmer apparatus, the Greenburg-Smith impinger, and the dust collector recently described by Drinker, Thompson, and Fitchet. The Bureau of Mines has conducted investigations in many metal-mining districts of the country, determining of dust the nature and amount of dust present in working places, its effect the health of workers, and what precautions may be taken to decrease the hazard of exposure to dangerous dusts. The Bureau is therefore interested in any factor that affects the accuracy of dust sampling.

Nov 1, 1923

By T. M. Nasiatka

This report sterns from a study undertaken by the Federal Bureau of Mines to determine the possibility of reducing filter-cake moisture by applying radiant heat. Suitable laboratory equipment was set up to study the effect of heat, heating time, proximity of the heater to the filter cake, cake thickness, and other variables related to the final filter-cake moisture. A minus-48-mesh coal slurry and application of heat for 60 seconds resulted in filter-cake moistures 5.6 to 13.2 percentage points lower than could be accomplished by filtration alone at 24 inches of Hg for 1-1/4-and 1 1/2-inch cake thickness, respectively. The moisture reduction can be attributed to the combined effect of lower fluid viscosity and evaporation.

Jan 1, 1959

By David Hoadley, Kenneth R. Maser, Ashok B. Boghani, James E. Billar, D. Randolph Berry, Mackenzie Burnett, Robert H. Trent

1, Introduction This report is submitted in fulfillment of the requirements of USBM Contract No. J0255017, "Development of Emergency Escape Systems Guidelines for Underground Metal and Nonmetal Mines" Under this contract the history of past mine fires was studied. Representative metal and nonmetal mines were surveyed and escapeways, refuge chambers, life support, and emergency hoist requirements were studied to determine the problems in complying with the proposed regulatory standards and their enforcement by MESA Mine Inspectors. In addition, a computer program was written to evaluate mine evacuation performance. The completed program is included in the appendix. 1. 1 Historical Review of Metal and Nonmetal Mine Fires Early records of mine fires are poorly documented because there was no statutory provision for reporting fires to the Bureau of Mines. The survey of representative mines during the course of this contract indicated that many small fires still go unreported even though they are now required to report all fires A recent report survey approximately 80 disasters in metal and nonmetal mines, (6 ) Table I is a summary of some of these fires. Historically most metal and nonmetal mine fires have been caused by electrical problems. Spontaneous combustion and the use of welding equipment are the other major causes of mine fires(14) Although not documented, many mine personnel agree that 30 percent to 40 percent of underground metal and nonmetal mine fires have their origin from cigarettes and other smoking related materials. The number of fires related to spontaneous combustion is decreasing and equipment fires are on the increase. The reduction of spontaneous combustion fires can be attributed to the use of sandfill in more mines and the increase in equipment fires to the increased use of LHD equipment.

Jan 1, 1976

By M. M. Hassan

This report describes the analysis tools developed at West Virginia University which can be implemented to optimally design coal mine electrical systems. The basic analytical tools for all power systems are the load-flow and short-circuit analysis. Well known programs have been developed for analysis of ac transmission and distribution systems, but they are not applicable to a system which has combined ac/dc distribution, such as a coal mine power system. Furthermore, the topology of a coal mine electrcal system changes continuously due to the movement of the locomotives on the track. In the first section of this report, algorithms for carrying out load flow and short-circuit analysis of a coal mine electrical system are described. Results from the study of a typical coal mine system are presented. In the second section a method is described to optimally size power cables for cyclic loads. The method is based on the development of a thermal-electric model for a low-voltage power cable. Results from experimental verification of the model are also presented. These techniques are useful in the safe, efficient, reliable and economical design of the coal mine electrical power systems.

Jan 1, 1979