Search Documents

By R. E. Heithecker

In Kansas, almost every oil well drilled into a limestone formation is treated with hydrochloric (muriatic) acid upon completion. This is done to increase the potential capacity of the well and thereby increase its "daily allowable" production (see p. 9 ), to shorten the time required to produce the recoverable oil, and to increase the quantity of oil recovered ultimately from the reservoir. The porosity and. permeability of limestone formations seldom are uniform throughout the proved area, consequently the production capacities of completed wells vary considerably. Acid treatment of wells tends to increase production capacity and to equalize potential capacity. If offset wells already have been treated with acid, new wells usually are treated to protect the property on which they are drilled against drainage. Even though competitive conditions do not exist in a field, it

Jan 1, 1939

By R. E. Heithecker

In Kansas, almost every oil well drilled into a limestone formation is treated with hydrochloric (muriatic) acid upon completion. This is done to increase the potential capacity of the well and thereby increase its "daily allowable" production (see p. 9), to shorten the time required to produce the recoverable oil, and to increase the quantity of oil recovered ultimately from the reservoir. The porosity and. permeability of limestone formations seldom are uniform throughout the proved area, consequently the production capacities of completed wells vary considerably. Acid treatment of wells tends to increase production capacity and to equalize potential capacity. If offset wells already have been treated with acid, new wells usually are treated to protect the property on which they are drilled against drainage. Even though competitive conditions do not exist in a field, it

Jan 1, 1939

By Constantine C. Popoff

During 1946 several high-grade limestone deposits in western Washington were examined by the Federal Bureau of Mines. The purpose of the examinations was to disclose new sources of industrial limestone and to indicate the commercial potentialities of little-known and undeveloped deposits. These examinations were part of a long-range program of investigation of mineral resources of the Pacific Northwest. The following report on the Whitechuck travortine deposit is one of a series prepared in the course of the investigations.

Jan 1, 1949

By David Allen Jones

A depleted county gravel pit was rehabilitated by contracting an artist to convert it into sculpture, rather than using traditional reclamation methods. The sculptor's ideas were generally implemented as designed, but problems arose because of a faulty survey and severe weather. Public reaction was critical. A design symposium was presented by retaining six artists to prepare designs for varied sites. A public forum was offered and video-documented for broadcast. A new art-reclamation project grew out of this project.

Jan 1, 1981

By Larry R. Powell

As part of the Bureau of Mines effort to establish a comprehensive subsidence data base for subsidence technology development, subsidence and related data are being compiled for various mining, geological, and environmental situations. This publication presents data for two longwall mining operations in the Northern Appalachian Coal Region. Vertical displacements and relative face positions are tabulated for 104 subsidence monuments. Brief physiographic and geological descriptions of the mining sites are presented along with a general account of the mining and subsidence monitoring methods.

Jan 1, 1981

By LaMar G. Evans

The rapid determination of uranium in ores by radiometric means was investigated by the Bureau of Mines. Among the various procedures and schemes tested, two showed most promise. They were the ratio scheme developed in the Bureau's Tucson, Ariz., laboratory and the equilibrium method developed by the Canadian Department of Mines and Technical Surveys. The ratio method is a simple, empirical procedure for classifying the state of equilibrium in ores by measuring their radioactivity by means of a Geiger-Muller counter under three different conditions, using filters. The principal merit of the method is in providing a clue as to the reliability of equivalent uranium determinations.

Jan 1, 1958

By C. W. Owings, F. E. Cash

"Transportation of explosives in mines is extremely hazardous, and where electric haulage is employed the danger is intensified. Insulated mine-car couplings have been adopted by at least five companies in Alabama and Pennsylvania - and undoubtedly in other States - to prevent an electric current passing from a mine locomotive to a car or between care joined by this coupling. The need for such protection is recognized in the report of an explosion.""Four hundred kegs of black blasting powder had been loaded into four mine cars at the railroad, to be hauled to the magazine, upgrade, by a trolley locomotive. On starting, the motorman put sand on the rail and a grounded circuit passed through the hitchings and so exploded the powder. No insulation was used between the locomotive and cars."" When used on man trips the insulated coupling further serves the purpose of guarding the men against shock. Four couplings are described so that a clearer understanding may be obtained of the details of construction.ConstructionThe general principles of construction are similar in all insulated couplings. The piece containing the hole for the coupling pin is made of steel and the steel parts are separated by an insulating material, such as fiber or wood. The coupling is either rigid or semirigid to prevent the bumpers of the mine cars from coming in contact and to keep the cars insulated from one another at all times."

Apr 1, 1928

By B. J. Dalton

The Bureau of Mines Helium Research Center has as a long-range objective the development of an equation of state for helium that will allow all of the thermodynamic properties to be calculated within the accuracy with which they are known. If this objective is to be realized, a method of calculation must be known. This report gives the principles of the method we use in such problems. A computer program was developed for predicting these properties, including those at the critical point, that is perfectly general and applicable to any equation of state. To demonstrate the efficacy of our method, this computer program was used to evaluate thermodynamic properties of a Redlich-Kwong fluid in the two-phase region. Expressions for calculating various thermodynamic functions specific for this particular equation of state are derived. Numerical values are tabulated and graphs are presented for all functions calculated. It is shown that for a Redlich-Kwong fluid there are finite discontinuities in (1) the second temperature derivative of the Gibbs free energy or chemical potential at the critical point, (2) the second derivative of the vapor pressure curve with regard to the temperature on passing through the critical point, and (3) the measured heat capacity at constant volume on passing through the critical temperature when the calorimeter is filled to the critical density. It is also shown that the heat of vaporization is infinite for a Redlich-Kwong fluid at absolute zero.

Jan 1, 1969

By Stanley K. Haines

This Bureau of Mines publication comprises 19 tables of data concerning domestic barite production and consumption, imports, and world production for the years 1880 to 1976. Barite is vital to the petroleum industry, with 90 percent of domestic consumption used in drilling muds. Domestic production has traditionally fallen short of consumption: in 1976, 41 percent of the 2.2 million tons consumed was imported. World production of barite increased from 269,000 tons in 1923 to 5.2 million tons in 1975 but is in danger of falling short of future demand. The compiled data provide a comprehensive base of information.

Jan 1, 1978

By E. L. Sweeney

The mine and mill of the Davis-Dunkirk Lines, Inc., are about 16 miles by road south of Prescott, Ariz., which is the nearest railroad point for receiving mine and mill supplies and for shipping concentrates to smelters. A good trucking road reaches within 2 miles off the property, but from that point the grade is very steep. Outgoing loads are limited to 2 tons. The topography near the mine is exceedingly rugged, and the area is slightly wooded. The climate is mild excepting in a few winter months, when the snowfall is heavy. Electric power is secured by way of a 4 1/2-mile, high-tension line connecting with the main line of the Arizona Power Co. The concentrator was intended to treat 60 tons or more daily of gold-silver-copper ore and make a single gold-silver-copper concentrate for shipment to a copper smelter.

Jan 1, 1933

By H. K. Sacks

The Bureau of Mines has improved a mine dust incombustibles analyzer originally developed at the Bartlesville Energy Research Center (BERC). This analyzer provides quick, accurate analysis of the percentage of incombustible material present in dust samples taken from mine ribs, roof, and floor so that costly overdusting may be eliminated while still maintaining a proper level of incombustibles. The changes being effected on the present design of the BERC model IV rock dust analyzer should simplify its operation and calibration procedures, resulting in increased accuracy.

Jan 1, 1976

By Will H. Coghill

Recent work on beneficiation of the .Alabama red iron ores and ferruginous sandstones has brought out interesting new facts on particle-size reduction that axe a valuable supplement to what is already known.4/ The work was done by the Southern Experiment Station of the Bureau of Mines in cooperation with-the University of Alabama, University, Ala., on two samples from the Birmingham district. One was an oolitic red iron ore containing about 35 percent iron; the other was a ferruginous sandstone containing about 25 percent iron, particularly attractive because of its low phosphorus content. In both samples rounded quartz (sand) grains were embedded in an oolitic, "onion skin" matrix of hematite. The hematite carries varying amounts of clay, which limits the grade of concentrate that can be made. The clayey hematite is soft, so that the rock crumbles readily under pressure. The sand grains shell out like corn,, and without much exaggeration the mill used for differential grinding might be called a "sheller,"

Jan 1, 1940

By Will H. Coghill

Recent work on beneficiation of the .Alabama red iron ores and ferruginous sandstones has brought out interesting new facts on particle-size reduction that axe a valuable supplement to what is already known.4/ The work was done by the Southern Experiment Station of the Bureau of Mines in cooperation with the University of Alabama, University, Ala., on two samples from the Birmingham district. One was an oolitic red iron ore containing about 35 percent iron; the other was a ferruginous sandstone containing about 25 percent iron, particularly attractive because of its low phosphorus content. In both samples rounded quartz (sand) grains were embedded in an oolitie, "onion skin" matrix of hematite. The hematite carries varying amounts of clay,-which limits the grade of concentrate that can be made. The clayey hematite is soft, so that the rock crumbles readily under pressure. The sand grains shell out like corn,, and without much exaggeration the mill used for differential grinding might be called a "sheller,"

Jan 1, 1940

By E. J. Kloos

Two self-contained breathing apparatus of the closed-circuit compressed-oxygen type were evaluated for performance at 32° to -25° F. Low-temperature effects of oxygen and carbon dioxide concentration, visual properties of the facepiece, and mechanical operation of the apparatus were studied. Although operation varied with the wearer, his breathing rate, the apparatus precooling time, and the temperature, results suggest that general use of currently approved compressed-oxygen closed-circuit breathing apparatus be limited to temperatures above 32° F.

Jan 1, 1968

By D. D. Bolstad

This report describes the construction and use of a direct-reading azimuth protractor (DRAP) by the Bureau of Mines for measuring fracture orientations in mines, tunnels, or other excavations having a magnetic environment. The DRAP allows a rapid and simultaneous measurement of dip and azimuth of dip of a fracture plane. The instrument is rugged, lightweight, and easily constructible from standard hardware items. The DRAP can measure dip to within ±0.5° and azimuth of dip to within ±5° of corresponding values obtained with a Brunton compass.

Jan 1, 1974

By Irvin Pritts

This report describes the design, fabrication, and testing of a prototype instrument which demonstrates the feasibility of determining respirable coal dust concentrations by light reflectance photometry. Coal dust is collected on a filter and the quantity collected is continuously monitored by reflectance-photometry. Light emission and detection is accomplished by reflective object sensors, which have both light source and detector in one chip. The use of a pulsed light source insures low drift characteristics of the measuring circuitry. The collection of the respirable coal dust on filters facilitates accurate calibration and also allows measurement verification, if desired, by well-accepted, gravimetric methods.

Jan 1, 1981

By L. W. Higley

It is estimated that well over 20 million lb of chromium and 8 million lb of nickel, plus other metal values, are diverted annually to furnace dusts, mill scale, and contaminated swarfs in the domestic stainless and other specialty steelmaking industry. Little inroad has been made toward the in-plant recycling of these wastes to reclaim the metal values. The Bureau of Mines has devised a process for recovering about 90 pct of the chromium and molybdenum and well over 90 pct of the nickel and iron from stainless steelmaking furnace dusts, swarf, and mill scale. Other metals such as manganese are also recovered. Initial laboratory results were confirmed and expanded to include a wide variation of stainless steelmaking waste mixtures. Later experiments have included specialty steelmaking wastes other than from stainless steelmaking. Significantly, the ease of technology transfer has been demonstrated by a number of industrial-sized (19-ton) commercial electric furnace heats, in which the pelletized wastes represented some 10 to 20 pct of the furnace charge, replacing part of the normal scrap charge. Results of these successful large-scale trials are presented. Some information is also presented on incorporation into the pellets of chromium-bearing particulate wastes originating from other than steelmaking production. Cost evaluation indicates the process is economically attractive.

Jan 1, 1982

By Joel N. Van Sant

An investigation was conducted to study possible sources of Utah refractory and structural clays that could be used for the manufacture of refractories and light or buff burning heavy-clay products. A field study was made and the clay samples tested to determine their firing characteristics. Results of the Bureau's work indicate many small noncommercial deposits of hypogenic clay occur in igneous rocks. Commercial hypogenic deposits are mostly halloysite clay developed by hydrothermal replacement of limestone. The high firing shrinkage of halloysite precludes its use as a refractory, however, halloysite produced at the Dragon Mine south of Eureka, is used for making oil catalysts. Clays and shales suitable for low heat duty refractory products are found in the Manning Canyon shale, in shales associated with coal bearing rocks, and in the Dakota formation. Some of the clays from the Dakota formation are also suitable for high-duty refractory products.

Jan 1, 1964

By S. H. Ash

For several years considerable activity has been devoted to economic and social factors affecting California metal-mining operations as they relate to accidents and their cost. The reason for this intense interest is that accidents cost this industry annually over $1100,000 in industrial insurance premiums for mines insured by insurance carriers only; during 1924-32, inclusive, they amounted to $3,616,9115. There are several reasons for this high cost, the most important of w rich are the consistently .high frequency and severity rates of injuries occurring in the industry. Coordination of effort, appreciation of a mutual problem, and widespread education are essential if accidents and their cost are to be reduced.

Jan 1, 1935

By Forrest T. Moyer

The safety record of the coal-mining industry in 1968 worsened appreciably .in fatality experience but was slightly better in nonfatal-injury experience. Work fatalities in 1968 totaled 311 and occurred at a frequency rate of 1.33 per million man-hours or worktime. The fatality total was 89 higher, and the rate of occurrence was 45 percent higher than the corresponding figures of 222 fatal injuries with a frequency rate of 0.92 in 1967. The worsened fatality record in 1968 resulted primarily from two major disasters (a single accident which results in the death of five men or more) which killed 87 men, nine in one and 78 in the second. The total of 9,639 nonfatal injuries was the lowest annual figure in complete records back to 1930. The frequency rate of 41.12 nonfatal injuries per million man-hours of worktime for 1968 was the second lowest annual rate of occurrence. The severity rate of all injuries, 10,513 days lost or charged per million man-hours, and the average severity, 248 days lost per injury, in 1968 were the worst annual data in the series started in 1944. Total worktime of 234.4 million man-hours and coal output of 553.3 million tons in 1968 were, respectively, 3 and 1 per- cent lower than in 1967.

Jan 1, 1972