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By Kenneth D. Winters

This Bureau of Mines report presents a Fortran IV computer program for the structural analysis of (1) protective canopies used in underground mines to protect equipment operators from roof falls and (2) rollover protective structures (ROPS) used in surface mines to protect equipment operators during vehicle overturn accidents. The program, entitled PLASTIC CANOPY, permits rapid and inexpensive calculation of the ultimate strength and deformation characteristics of a canopy for a variety of static loading conditions. The structure is modeled as a series of interconnected beam and/or plate elements. Stresses in, and displacements of, each structural element are computed and printed out at the yield strength of the canopy, at several intermediate load levels between the yield and ultimate strength of the canopy, and at the ultimate strength of the canopy. Other features of the program include prediction of buckling of a beam member under combined axial compression loading and bending, plotting of the input geometry of the structure, and plotting of the deformed shape of the loaded structure. Program description, input instructions, program listing, and four example problems are included.

Jan 1, 1979

By D. E. Pollock, Andrew B. Cecala

It has long been known that ventilation is a cost-effective method to lower respirable dust concentrations in all types of mining applications. The National Institute for Occupational Safety and Health has been working on a number of different research techniques that use ventilation as a critical component to lower respirable dust levels at surface and metal/nonmetal operations in the United States. This article presents five such research efforts. The first research area discusses how improving the ventilation flow patterns in an iron ore mill facility lowered respirable dust concentrations by 31 pct throughout the primary grinding area. The second research area examines how respirable dust levels were lowered at a dimensional stone shop by using air cleaning units suspended from the ceiling. A third area discusses how improvements in ventilation at underground limestone mines lowered respirable dust concentrations. The fourth area examines how improvements in dust filtration and pressurization systems significantly impacted the air quality in enclosed cabs of surface mining equipment. The last area presents a newly developed clothes cleaning technique. This technique uses an air spray manifold to blow dust from a worker’s clothing in an enclosed booth, which confines the dust for capture and removal by a baghouse dust collector. These research areas represent an array of different control technologies to lower respirable dust concentrations. Ventilation is an integral part of these control technologies.

By E. P. Buxton, W. P. Yant, G. W. Jones

"Introduction. The data obtained in recent research work by the Bureau of Mines show that the analysis of the gases dissolved in underground waters may be used by the prospector or geologist as an additional aid in discovering new oil or gas fields. The hydrocarbons present in the water serve to indicate whether oil or gas sands exist in the region through which the waters have passed. A portable field apparatus has been developed by the bureau which can be used for removing and analyzing the gases dissolved in the waters. This apparatus and the method of u are described in this paper. Results are given of analyses made on waters from various localities, and the significance of these waters with reference to the detection of oil and gas.Any liquid, with the exception of mercury, if permitted to come in contact with eases or vapors will absorb a definite amount thereof. This action depends on the following factors: (1) The kind of gas; (2) the percentage composition of the eases in contact with the liquid; (3) the pressure of the gas; and (4) the composition and temperature of the liquid. For our present purpose it is only necessary is consider two of these factors - namely, the gas or vapor (natural gas and light petroleum vapor), and the liquid (water).If water of underground origin traverses a gas or oil sand it will absorb a definite quantity of hydrocarbon vapors, and will carry these vapors to the surface when tapped by a well. When the water is exposed to the air at the sur¬face, the eases and vapors will be given off and their place taken by oxygen and nitrogen from the air. Therefore, an analysis of the gases in waters reaching the surface from an underground source should be of value in determining whether these waters have traversed or came in contact with hydrocarbon-bearing strata. With the apparatus herein described it is possible to determine whether the vapors are mainly of natural gas on sition (methane CH1) and ethane (C2H6 ), or are come posed mostly of heavier petroleum vapors (ethane, propane (C3E8) and buttane (C4H10)."

Nov 1, 1923

By Joseph P. DuCarme

The U.S. Bureau of Mines explored new methods and technology for extracting coal from the Appalachian Mountain region of the Eastern United States. These methods were aimed at extracting coal from thin seams and focused on the use of "roof-fall-tolerant" (RFT) mining concepts. These methods could be used on existing, abandoned highwalls or in conjunction with new highwall mining. The research was conducted using small-scale and quasi-full-scale physical models to obtain experimental results. Details are provided on (1) the quasi-full-scale model for cross-ridge mining, (2) the quasi-full-scale model for down-ridge mining, (3) the test results of these models, and (4) recommendations for future research. Significant results include demonstration of the RFT concept, a discussion of expected coal produced from these methods, and recommendations for future research.

Jan 1, 2010

By Gordon Bath

During the summer of 1946, the Division of Geophysical Exploration of the U.S. Bureau of Mines established several primary magnetic base stations near important iron-producing districts in Minnesota, Michigan, and Wisconsin. Stations were located in groups of four to six in six separate base-station areas, and each position was marked with a concrete monument. Differences in magnetic intensity between stations in these areas, as well as the difference between each area and a magnetic datum at the magnetic observatory of the Coast and Geologic Survey at Cheltenham, Md., were measured with a modified Askania magnetometer. Measurements also were made with a Hotchkiss superdip to study the usefulness of the stations for the calibration of instruments of this type. The work was planned and supervised by F. W. Lee, chief of the Division of Geophysical Exploration, and Edward F. Fitzhugh, Jr., chief of the Minneapolis Division of the Bureau of Mines. Special mention is due Harold B. Ewoldt, Bureau of Mines engineer, for his assistance in the field work, especially in locating and establishing monuments. Special mention also is due Clyde L. Holmberg, of the Bureau of Mines, for the magnetic measurements made with the Hotchkiss superdip. Helpful suggestions were received in the field from H. L. James, of the U. S. Geological Survey. Acknowledgment is made of the cooperation of Stephen Royce, Irving E. Beckwith, Arthur Johnson, and Josiah Royce of Pickands, Mather & Co., and A. E. Matson, of Butler Bros. The U. S. Coast and Geodetic Survey furnished daily magnetograms from the Cheltenham Magnetic Observatory as well as calibration equipment and values of absolute magnetic intensity. Short-term forecasts of ionospheric conditions were obtained from the National Bureau of Standards.

Jan 1, 1951

By Russell J. Gartrell

This report describes the engineering feasibility and economic advantages of using a steep angle conveyance (SAC) system in conjunction with medium and large draglines to transport spoil in a typical Western Coal Mine. The SAC system, including a receiving hopper, a steep angle conveyor and a sticker/spreader, is capable of processing overburden material at the rate of 7,000 tons/hr. The unique feature of this system is the steep angle conveyor which transports the overburden material from the pit bottom to the top of the spoil at angles to 45 degrees. Compared to other means of cross-pit conveyance considered during this study, the SAC system offers the advantage of easier operation, lower conveyance cost and greater mobility. The results of this study have shown that integration of the SAC system into both established and planned new mines would improve the overall mining operation, expand the operating capability of existing equipment and reduce mining end reclamation cost.

Jan 1, 1977

By Russell Griffin

The current state of the art of fire and smoke detection technology is reviewed from the standpoint of suitability for use in under- ground metal and nonmetal mines. Detection modes, fire signatures, and environmental considerations are included. Preliminary results of long- term, in-mine tests are presented.

By Avery H. Reed

ALABAMA'S mineral industry continued to expand. This was a record year for many commodities, with expansion in almost all industries. New records were established for the production of native asphalt, fixe clay, miscellaneous clay, kaolin, bentonite, lime, scrap mica, salt, sand and gravel, crushed limestone, crushed marble, and tale. Among the States, Alabama ranked second in the production of bauxite, third in the production of scrap mica and native asphalt, and fifth in iron ore. The mineral industry of Alabama was dominated by the mining and processing of coal and stone, the manufacture of cement, and the production of crude petroleum, which together comprised 87 percent of the total value of production, compared with 86 percent in 1963. The iron ore industry continued to decline. This was the first year in which consumption of imported iron ore exceeded the consumption of domestic iron ore. The coal industry recovered from the slump caused by the abandonment of red iron ore mining by United States Steel Corp., and production expanded 17 percent, for the best year in coal mining since 1948. During the year, the one-billionth ton of coal was mined within the State.

Jan 1, 1965

By Oliver Bowles

Marble is one of tile most beautiful and enduring materials employed in the construction industries. Because of its diverse colors, decorative patterns, and varying textures, it has furnished material for artistic architectural design for many centuries. The marble industry is described in some detail in Bureau of Mines Bulletin 106, The Technology of Marble Quarrying, which, unfortunately, is now out of print but may be consul ted at most large libraries. Onyx marble and travertine are discussed in Bureau of Mines Information Circular 6751. The purpose of this paper is to describe the main features of a distinctive group of ornamental marbles known as the serpentine marbles or verde antiques.

Jan 1, 1938

By T. L. Joseph

The Bureau of Mines gas been studying the blast furnace for a number of years and has published detailed reports on various phases of its investigations. Inquiries frequently received for information of a more general character than that given in the detailed reports have promoted the preparation of an information circular to cover in a general way the important features of the Bureau of Mines blast-furnace investigations. SHAPE AND DIMENSIONS OF FURNACE The modern blast furnace approximate a refractory-lined steel cylinder about 90 feet in height and 25 feet in diameter. It actually consists of a number of cylinders and truncated cones superimposed upon each other. The shape and dimensions of a modern furnace are shown in figure 1. The bottom section, commonly referred to as the hearth or crucible, is a cylindrical section about 12 feet high. Liquid metal and slag collect in this part of the furnace and are withdrawn at regular intervals; iron is removed at a level about 2 feet above the bottom of the furnace and slag at a level about 5 feet higher. Depending upon on the size of tie furnace, 40,000 to 75,000 cubic feet of preheated air per minute is introduced through from 10 to 16 tuyeres equally spaced around the periphery of the hearth.

Jan 1, 1934

By S. H. Ash

THE INVESTIGATION of barrier pillars in the Southern field is part of the comprehensive study of the mine water problem in the anthracite region of Pennsylvania by the Federal Bureau of Mines (1, 2, 5, 6, 7, 8, 9, 10, 11, 12, 15, 16, 18).4 Tim Southern field is in Carbon, Schuylkill, Dauphin, and Lebanon Counties, in eastern Pennsylvania; has an area of 200 square miles; is 70 miles long from Mauch Chunk on the east to the Susquehanna River on the west; and is 1 to 6 miles wide. In the Southern field are 37 underground water pools containing 37312 billion gallons of water (5). Most of these pools overflow to the surface because the barrier pillars controlling them are effective under existent, conditions. Abandonment of mines in the Southern field has resulted in the hooding of 34 percent of the field. The largest tonnage of reserves of anthracite lies in this field, where mining conditions are most difficult. Large reserves of anthra¬cite underlie the abandoned mine workings, and before a great part of these reserves can be developed and extracted, the abandoned workings must be unwatered and kept drained (5).

Jan 1, 1953

By G. R. Smith

Critical and strategic metals are often present in small quantities in low-grade domestic ores. When these ores are leached, the resulting solution usually contains the metals in very dilute quantities. Selective electrowinning from dilute electrolytes was investigated by the Bureau of Mines. A metal deposit containing 84 pct nickel was electrowon from the leach solution of a complex domestic ore bulk flotation concentrate originally containing approximately 2 wt-pct nickel. Key to achieving accelerated deposition rates, in the case of dilute solutions, is the rapid movement of the electrolyte through the electrowinning cell. Pure, synthetic nickel electrolytes were used to establish deposition parameters, and to optimize electrolyte velocity or mass transfer rates. Hydrodynamic and electrodeposition parameters for both the synthetic and leach electrolytes are presented and the experimental research described. Selective electrowinning appears to offer a viable alternative to physical separation methods to obtain separate metal "concentrates" from low-grade ores.

Jan 1, 1983

By C. R. Sponsler, O. C. Blade

"INTRODUCTION This report on the properties of motor fuels sold through service stations in the United States is a continuation of a series of reports made in accordance with a cooperative agreement between the Coordinating Research (CFR) Committee of the Coordinating Research Coouncil (CRC) 4/ and the Bureau of Mines of the United States Department of the Interior. The first of these reports presented data on motor gasolines sold during the winter of 1935-36. 5/ Further reports were issued describing motor gasolines sold during the succeeding summers and winters to and including the summer of 1941. 5/ reports were made on motor gasolines sold during the winter of 1941-42 and during the summer of 1942. However, starting with the winter of 1942-43, the semiannual reports were resumed. 5/The present report presents analytical data for samples, representing the products of approximately 100 companies. Most of the samples represented in this report were obtained during December 1)55 and January 194o. As in previous surveys, the companies covered by the survey include both large and small suppliers. Conforming to former reports, the data cover three groups of samples - regular-price, premium-price, and third-grade gasolines.As the number of analyses submitted for samples of third-grade gasoline are not considered adequate to represent this type of motor fuel, data for the analyses have not been averaged, but the individual items are tabulated. The number of samples, items, and brands comprising each group is as follows:Regular-price, 1,958 samples, 317 items, and 96 brands; premium-price, 1, samples, 292 items, and 85 brands; third-grade, 58 samples, 22 items, and 14 brands. The meanings of these terms as used in the surveys are as follows;"

Jul 1, 1946

By Robert M. Becker

This investigation (in five parts) extends the theory of sample reliability from a sample consisting of a fixed number of items to a sample consisting of a fixed amount of items. Examples of a fixed amount of items per sample are samples consisting of a fixed weight or a fixed volume of unequal size particles. The extension of the theory is confirmed by experimental laboratory sampling using standard procedures. The probability distribution functions (the binomial, hypergeometric, multinomial, generalized hypergeometric, and those here called the compound binomial and compound multimomial functions) are developed from fundamentals. Their distributions are generalized to include some measured characteristic of the items. Infinite population moments are derived from moment-generating functions, and finite population moments are developed from corresponding infinite population moments using a newly defined mathematical operation. The first three experimental moments in laboratory sampling to given weights of particles are compared with the theoretical moments of their corresponding compound mult.inomial distributions. The agreement is striking. The study is divided into five parts. Part 1 deals with probability or random sampling to n items and with all sampling to n items per sample from some one probability distribution. This is the area of sampling covered by well-known theory. Accordingly, the procedures may be different but many of the results are well known.

Dec 1, 1964

By Allen S. Smith

Analysis of the helium content of a natural gas presents more than the usual difficulties encountered in applying the thermal-conductivity method because of the relatively small amounts of this inert as present and the wide variation in the other constituents. However, the numerous advantages of this method and its adaptability to Continuously recording and control instruments make it worthy of consideration. A specific application of the method described yields quantitative results only when used with gas mixtures of known qualitative compositions which Vary within predetermined limits. Periodic analyses for the helium content of a producing gas well may be conveniently made by an absorption method, and a continuums analytical method is not necessary for this purpose. Natural gas containing 1.75 to 1.90 percent of helium produced from Government-owned wells is processed in the Amarillo (Texas) Helium Plant of the Bureau of lanes. The helium extracted in the plant is supplied to the Army and Navy, and the processed natural gas is sold to a commercial gas company. As complete recovery of the helium in the raw material is not economically practicable, the processed gas contains 0.1 to 0.3 percent of helium, depending upon conditions of operation. Production is checked against the helium removed from the gas, which before the installation of the thermal-conductivity apparatus was calculated from the analysis of a cumulative sample of the processed gas. As conditions of operation affect the residual helium content to a large extent, a composite sample was an uncertain index of the efficiency of the process.

Jan 1, 1934

By Shail J. Butani

In 1986 the Bureau of Mines conducted a probability sample survey, Mining Industry Population Survey, to measure such employee characteristics as occupation; principal equipment operated; work location at the mine; present job, present company, and total mining experience; job-related training during the last 2 years; age; sex; race; and education. The population estimates are necessary to properly analyze the Mine Safety and Health Administration (MSHA) injury (includes illness and fatality data) statistics; that is, to compare and contrast injury rates for various subpopulations in order to identify those groups that are exhibiting higher than average injury rates. This report uses the survey's results to characterize the U.S. nonmetallic mining workforce from March through September 1986. Similar reports have been prepared for the metallic, stone, and sand and gravel mining industries, as well as for the entire metal and nonmetal mining (includes metallic, stone, sand and gravel, and nonmetallic industries) sector and the cool mining sector.

Jan 1, 1988

By W. E. Tournay

In accordance with a cooperative agreement between the Bureau of Mines, United States Department of the Interior, and the Linde Air Products Co., an investigation was made at the Bureau Explosives Testing Station, Bruceton, Pa., to develop suitable test methods for evaluating the performance and sensitivity characteristics of liquid-oxygen explosives. This report presents the results of the investigation. The unique nature of liquid-oxygen explosives necessitated both modification of standard techniques and development of entirely new test methods. The latter requirement was due to the fact that differences exist in the kind of information that must be developed for studying relative safety and performance properties of these explosives compared to that of fixed explosives.

Jan 1, 1949

Prier to the date of this contract, Ocean Energy had developed and demonstrated a high efficiency fluorescent caplamp which operated from a standard 4 volt miner's caplamp battery. This unit produced about five times the light output of the standard incandescent miner's caplamp. The Company believed that the major market for this unique caplamp was in the industrial and municipal applications. Because of the additional safety requirements for coal mining use, and in conjunction with the much smaller market in the mining industry, the additional expense and difficulty of modifying this caplamp to comply with the Federal and State coal mine regulations were not considered at that time. Recognizing the potential of this lamp for improving illumination conditions for underground coal mining, the US Bureau of Mines contracted with Ocean Energy to make the required modifications to this lamp to bring it into compliance with the Federal and State of Pennsylvania regulations, and thereby, make this lamp available to the anthracite and bituminous coal mining industry. At the outset of the contract, the injection molds for the caplamp housing were being completed, and only prototype, hand fabricated, units were available for tests. The Bureau evaluated these prototype units and formulated a performance specification for the miner's version. Light level and distribution, weight, size, angle of tilt, and operating duration were all specified. In addition, it was required that the caplamp be com¬patible with existin charging equipment at the mines and that the final design be in full compliance with MESA Schedule 6D and he ultimately approved by MESA, Approval and Testing, as well as by the Pennsylvania Bureau of Deep Mine Safety. The scope of this contract covered the modifications required to achieve these objectives. It was agreed by the Bureau that all rights to the lamp, including design, material combinations, circuitry, etc. would remain with Ocean Energy. The charger/adapter system and components, which were developed under contract funds, are disclosed hero and become public knowledge and property. Patent applications have been filed by Ocean Energy to protect the mechanical and electrical design aspects of the lamp. It should be noted that this report contains details, designs and data which may be covered by one or more Ocean Energy patent applications, and disclosure herein is made only to provide better understanding of the contract results.

Jan 1, 1975

By A. B. Cecala

It has long been known that ventilation is a cost-effective method to lower respirable dust concentrations in all types of mining applications. The National Institute for Occupational Safety and Health has been working on a number of different research techniques that use ventilation as a critical component to lower respirable dust levels at surface and metal/nonmetal operations in the United States. This article presents five such research efforts. The first research area discusses how improving the ventilation flow patterns in an iron ore mill facility lowered respirable dust concentrations by 31 pct throughout the primary grinding area. The second research area examines how respirable dust levels were lowered at a dimensional stone shop by using air cleaning units suspended from the ceiling. A third area discusses how improvements in ventilation at underground limestone mines lowered respirable dust concentrations. The fourth area examines how improvements in dust filtration and pressurization systems significantly impacted the air quality in enclosed cabs of surface mining equipment. The last area presents a newly developed clothes cleaning technique. This technique uses an air spray manifold to blow dust from a worker?s clothing in an enclosed booth, which confines the dust for capture and removal by a baghouse dust collector. These research areas represent an array of different control technologies to lower respirable dust concentrations. Ventilation is an integral part of these control technologies.

Jan 1, 2006

By T. G. Carnahan

In-place leaching is being actively utilized to extract uranium, copper, and evaporites from low-grade and difficult-to-mine ores. The purpose of this report is to discuss in-place leaching technology, its advantages and disadvantages, and to give an overview of past, current, and envisioned in-place leaching operations in the U.S.A. Application of in-place leaching to uranium ores has been particularly successful because the conditions for leaching are nearly ideal. The ores are generally in highly permeable sandstone aquifers bounded above and below by impermeable shales. The uranium ore minerals are easily leached with oxidizing acid or base solution and the pregnant solutions are amenable to ion exchange concentration and purification prior to conventional solution neutralization for recovery of yellow cake. Copper is routinely recovered from sub-grade rock by dump leaching at most major copper mines. Acidified ferric sulfate is either sprayed on the surface of the dumps or is ponded on top of the dumps. The leaching solution migrates down through the rock and dissolves copper. The solution is collected from the base of the dumps and copper is recovered by solvent extraction-electrowinning or by cementation on detinned steel cans. True in-place copper leaching is being practiced in the caved stopes of an exhausted underground copper mine. Other innovative in-place copper leaching techniques have been tested commercially and laboratory- and pilot-scale experiments have been conducted to investigate proposed in-place leaching techniques for extracting copper from difficult-to-treat chalcopyrite ores. Solution mining of evaporites is being conducted commercially for the extraction of sodium chloride and potassium chloride. A large-scale experimental project for solution mining of trona has been undertaken.

Jan 1, 1982