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By J. P. Walker

"INTRODUCTION Sponge iron has been made commercially since 1912 at a Swedish ceramic plant; and the product, known as Swedish disk-type nagger sponge iron, has an excellent reputation as a superior furnace feed wherever high-grade steels are made.The general procedure for making brickyard sponge iron was described frequent in Swedish technical journals before 1932 and at that time consisted in filling clay refractory containers, called saggers, with iron ore plus the necessary quantity of solid reducing agent and then firing in an ordinary ceramic kiln. Two types of sponge iron were made in this way: (1) An inferior, high-sulfur product obtained by mixing the ore and solid reducing agent; and (2) a high-grade, low-sulfur product made by filling the sagger with alternete layers of unmixed ore and reducer, yielding sintered disks of metallic iron particles.Swedish disk-type sponge iron of interest to the steel industry because it has a very low sulfur content, even when made by the use of low-grade, high-sulfur coals for reducing and firing. The Swedish product also contains little siliceous gangue residue and is almost phos¬phorus-free. To those features must be added the high metallic-iron content -90 to 96 percent - and freedom from even small amounts of the metals that are undesirable in steel making.The details essential for successful operation of this procedure are not known, especially as regards improvements said to have been made since 19;2. The Bureau of Mines therefore decided to determine some of these missing details, and this report records the results of the first set of experiments on the manufacture of brickyard or sagger sponge iron."

Sep 1, 1945

By Robert L. Lappi

Volume I of this report described the demonstration of cross-ridge mountaintop coal mining. This document, Volume II, is intended for use as a supporting document to Volume I. This report describes the MATHMINE Mine Simulation System, a modularized software system used to support the demonstration of cross-ridge Mountaintop coal mining. The MATHMINE Mine Simulation System was used to generate mine plans for coal extraction at lowest cost. The functional details, data requirements and output of the software system are detailed here. The computer program was written in FORTRAN. One module which generates resource location data required the use of SAS?.

Jan 1, 1984

By A. E. Sands

This report deals with a portion of the research and development work in the field of synthesis gas purification, carried out by the Bureau of Mines at its Morgantown, W, Va., Station in cooperation with West Virginia University. The Bureau's work in connection with gas purification has been performed with the objective of finding effective, low-cost, processes for removing impurities from synthesis gas to protect the catalyst used in the Fischer-Tropsch process for production of liquid fuels. Synthesis gas used for the production of other chemicals, such as ammonia, alcohols, and methane, requires equally rigorous purification. Although present-day practice in the manufactured-gas industry does not require such a high degree of purification, there is increasing interest in the complete removal of sulfur compounds from city gas. Although the gas-purification work at Morgantown deals with several impurities, major effort has been devoted to organic sulfur compounds in gas; this paper represents a progress report on some of the more important studies in connection with those compounds. Because this is a progress report on the Bureau's experimental work, no attempt has been made to cover the work of others on the subject; references to the literature have been restricted to those bearing directly on the work described.

Jan 1, 1950

By Gary L. Hundley

The Bureau of Mines has devised and demonstrated a process for recovering Ni and Co from low-grade domestic laterites. The process consists of four major steps: (1) reduction roast, (2) ammoniacal leach, (3) solvent extraction, and (4) electrowinning. Several solid-liquid separation steps are required that affect the economics of the overall pro-cess. In this study, two techniques for solid-liquid separation, centrifugation and thickening, were investigated. This report presents the results of (1) laboratory and pilot plant studies to determine parameters for sizing centrifuges and thickeners and (2) an economic study of the two techniques, based on the requirements of a commercial-size (5,OOO-tpd) laterite processing plant. Sizing and other equipment-related recommendations, based on data from the Bureau's studies, were obtained from commercial manufacturers. The costs of thickening and centrifugation, including all the unit operations affected, were determined by the Bureau's process evaluation group. The total operating costs ~or separation using the two techniques (including depreciation on the capital cost of equipment) were found to be quite close: $17.26 per ton of laterite for centrifugation and $18.15 per ton of laterite for thickening. For centrifugal separation, the greatest cost was found to be the initial capital cost for the separation equipment; using thickeners, the greatest cost was for re-agent recovery.

Jan 1, 1984

By D. Harrington

Metal-mine fires in the United States are not of frequent occurrence and relatively for of those that do occur result in loss of life, although many cause heavy property loss or are costly to extinguish. Over a span of years, however, more lives are lost in metal Trines from fires than from any other of the untoward occurrences which afflict metal mining, such as electrical storms, floods, cave-ins, magazine explosions, or strikes. In perhaps more than 90 per cent of the fires. in metal mines' there is no loss of life; hence, the general public, even the general mining public, seldom hears of these fires, though the property loss frequently reaches hundreds of thousands of dollars; on the other end, in some instances the property damage from an underground metal-mine, fire has been negligible and the loss of life comparatively high. In any comprehensive study of metal-mine fires, ventilation is certain to be found a vital factor. The influence of ventilation on fires and the influence of fires on ventilation are of vital importance. In metal-mine fires very few persons meet death from actual contact Pith heat or flame; nearly all fatalities are duo to asphyxiation or suffocation. A well-planned, well-installed, and well-operated mechanical ventilation system is unquestionably one of the best available present-day protections from loss of life and property in case of fire in a metal mine; that this is true is attested by the usual helplessness of mining officials in trying to handled underground fires in a mine that has not had the foresight to install mechanical equipment to control underground air flow. On the other hand, the establishment of high-velocity air currents without sufficient day by day attention to such details as the method of coursing, or controlling, or confining them most certainly tends to increase dangers from fires rather than to aid in the avoidance or elimination of these dangers; the truth of this latter statement is shown by the fact that the greatest, loss of life in metal-mine fires during the past 20 years has been in relatively well-ventilated workings, and in every case the life loss has been due to some more or less trivial or easily remedied defect in the Ventilating system - usually a defect that has had some reference to doors used or supposed to be used to deflect or control air currents.

Jan 1, 1933

By S. H. Ash

The coal-mining districts of Washington are mainly situated west of the Cascade Mountains. The eastern boundaries of Whatcom, Skagit, Snohomish, King, Pierce, and Lewis Counties, shown in Figure 1, form the backbone of the mountain range. The mines are on the foothills of the slope and extend to the shores of Puget Sound in the central and northern portions. The subbituminous fields of Lewis, Thurston, and Cowlitz Counties extend into the valleys west of the mountains. The Roslyn field, a small but important area, Lies on the eastern slope of the Cascade Range. If western Washington is divided into three areas from north to south the bituminous coal fields and most of the active mining operations will be found largely in the central area. In the southern portion there are large areas of subbituminous coals of varying quality extending from Centralia to the Columbia River. In the northern portion, mining is at present practically restricted to one mine which is working a subbituminous bed near the city of Bellingham.

Jan 1, 1931

By Rudolf E. Greuer

This report contains a theoretical study on the usefulness of fighting mine fires with inert gases. Four introductory chapters review the role of fires in the mining industry; the conventional fire fighting techniques, the influence of inert gases on the burning of gases and solids, and the well established inert gas fire extinguishing systems for buildings and machinery. A large chapter describes the use which inert gas has found so far for fighting mine fires in major mining countries. More applications have occurred than generally expected and the inert gas method has in the last years become routine in Czechoslovakia and the USSR. This chapter is based on an evaluation of the extensive literature as well as on personal information obtained from leading experts.

Jan 1, 2012

By S. H. Lorain

This paper briefly describes the principal known commercial and near commercial deposits of gold-bearing gravel end the principal placer mining operations of Idaho County, Idaho. It is one of a series of similar papers on western mining districts. The data used in writing this paper were gathered during the summer of 1937. Information concerning gold-bearing gravels was obtained from prospectors and operators, while operators supplied most of the data on mining operations. No attempt was made actually to test the gravels. The principal object of the examination was to indicate placer areas worthy of further investigation by prospective operators.

Jan 1, 1938

By R. W. Courtney

The objective of this study is to make a critical evaluation of the magnitude and extent of electrostatic hazards in typical U.S. mining operations and to assess the adequacy of techniques, materials, and equipment for detecting and minimizing these hazards. This was accomplished with an incident/accident survey, mine visits, literature search, and engineering analysis. It was concluded that it would be desirable to (1) utilize ground fault interrupters to minimize stray current from electrical utilities, (2) decrease the current and electrostatic sensitivity of electric detonators used in areas with a high incidence of lightning strikes or troublesome stray currents, (3) institute quality control and test standards for blasting material and protective devices, (4) establish an electrostatic monitoring program for loading ANFO in plastic lined holes, and (5) establish a risk criteria for operator exposure in mines.

Jan 1, 1982

During fiscal year 1966 the Bureau of Mines published 99 scientific and technical papers and engaged in 67 research projects on petroleum, natural gas, and oil shale. A basic appropriation of $3.4 million was supplemented by $1 million in cooperative funds from other Governmental agencies and industry groups. Petroleum conservation was advanced by development of scientific knowledge and improvement of technologic methods in both the extraction and utilization of petroleum, natural gas, and oil shale. Experimental work was carried out at research centers in Bartlesville, Okla., and Laramie, Wo., and in laboratories in Morgantown, W. Va., and San Francisco, Calif. ACHIEVEMENTS IN FISCAL YEAR 1966 Bureau of Mines--Petroleum Research in fiscal year 1966 (July 1, 1965- June 30, 1966) was involved in many public issues--air pollution, peaceful uses of nuclear explosives, utilization of oil-shale resources, computerization of recovery-stimulation techniques, and fuels for supersonic airplanes. Scientific contributions included compositional studies of petroleum and oil shale, determination of thermodynamic properties of petroleum compounds, development of analytical techniques, and correlations of petroleum properties with geologic occurrence. Technologic advances included rock-fracturing research, in situ combustion studies, waterflood techniques, use of radio-tracers to study stability of petroleum fuels, and hydrogenation as a tool to prepare shale-oil products.

Jan 1, 1968

By Charles L. Parsons

Early in 1912, from information received by the Bureau of Mines, it became evident that quantities of valuable radium-bearing ore from Colorado were being exported for manufacture in foreign countries and that at least part of the manufactured product was being returned to this country and sold at a price entirely incommensurate with that received by the miner and the prospector. Consequently, in line with its efforts to increase efficiency in the mining and treatment of mineral resources, the Bureau of Mines undertook an investigation of conditions. Results of this preliminary investigation were published, in the summer of 1913, as Bulletin 70,a which gave an outline of the radium deposits of the West, the conditions of mining, the wastes involved, and the status of the production of radium from its ores. At about this time newspapers and medical journals were publishing statements regarding the value of radium in cancer therapy. These reports, although many of them were exaggerated, brought out clearly the remarkable virtue of the gamma rays for the treatment of cancer and other malignant growths. In view of the fact that the largest known supplies of radium ore in the world are in the States of Colorado and Utah and on the public lands of the United States, it was deemed highly important for the Bureau of Mines to study the production of radium in detail. Such study, it was hoped, would enable the prospector and miner to obtain a fairer price for the ores and would furnish information necessary in case Congress appropriated funds to develop methods for extracting radium from ore on the public lands under Government supervision, to be supplied at cost to the hospitals of the Army, Navy, and Public Health Service.

Jan 1, 1915

By W. G. Pariseau

A two-dimensional finite element program has been modified and extended to account for some of the rock mechanics complexities associated with single entry development of longwall coal mine panels. Program capability includes arbitrary assignment of element properties without regard to element ordering, anisotropic elastic, plastic and brittle rock properties that may be time dependent (aging), arbitrary mining sequences and provision for the effects of artificial support on the adjacent strata. Failure is according to an extended von Mises criterion that may be linear or quadratic in form; flow rules are obtained from the yield function taken as the plastic potential, but brittle behavior is treated as a discontinuous process of material properties change with deformation. In either case the extent of failure is calculated from the external boundary conditions. Application of the program to essentially two-dimensional problems resulted in lose agreement between calculated displacements and field measurements in the double entry system. Bleeder entries were stable in one locality and not in another. Artificial support had little influence on stability.

Jan 1, 1978

By N. O. Johnson

This is one of a series of-Information Circulars dealing with mining and milling methods and costs at mines in various districts in the United States. The Hog Mountain gold mining district is of the northern edge of Tallapoosa County, in the east central part of the State of Alabama. The district is equally close to Goodwater and to Alexander City, both stations on the main line of the Central of Georgia Railroad. From Alexander City the mine is reached by 13 miles of graded road, traveling in a northeast direction. In dry seasons the road is good; in wet weather it is bad but passable. Improvements are being made constantly on the road, so that in the near future the gravel road should be good under all weathered conditions.

Jan 1, 1936

By Zsuzsanna Zborovszky

A circuit is considered intrinsically safe when any spark or thermal effect produced normally (that is, by operating the equipment in its correct operational manner to fulfill its purpose) or accidentally (caused by short circuit, earth fault, defective components, breaking the wiring, etc.) is incapable under prescribed test conditions of causing ignition of a prescribed gas mixture. The test conditions and gas mixture should be at least as hazardous as the true parameters of the environment where the circuit will be operated. According to present practices, the question of whether or not a circuit is intrinsically safe is decided upon experimentally. The circuit is inspected first for mechanical soundness and a survey is made to determine what faults should be considered as probable. Then the individual branches are connected, in sequence, to a test apparatus called 'breakflash" which acts as an opening, closing contact and thus draws sparks from the circuit. This test is repeated a given number of times in the presence of the prescribed gas mixture under specified conditions (electrode configurations, gas parameters, etc.). The equipment will be regarded as intrinsically safe if during testing no ignition has occurred.

Jan 1, 1972

The principal activities of the Bureau of Mines Explosives Research Center from July 1, 1962, to June 30, 1963, are described briefly in part 1. Part 2 gives short abstracts of publications that appeared during fiscal year 1963; in general, the research reported in these publications antedates the report period.

Jan 1, 1965

By E. E. Ungar

The ways in which noise is generated and radiated by chutes and screens are described and corresponding noise control concepts are discussed. The amounts of noise reduction produced by applicable noise control means are delineated and generally cost-effective means are recommended. Available noise control materials and their applications are discussed. The results of field measurements, laboratory experiments, theoretical analyses, and studies of data provided by suppliers are summarized.

Jan 1, 1975

By D. Harrington

The primary objective of this paper is to discuss the hazards and furnish a list of recommendations for the safe operation of quarries and related works. They have been compiled from Bureau of Mines publications covering the safety experience of engineers before and during the year in the mineral industry,5 from a publication of the National Safety Council, Inc.,6 from explosives recommendations made by various explosives manufacturers,7 and from suggestions obtained from quarries visited. The second objective is to describe and illustrate safety devices, practices, and quarrying methods. The quarrying and related industries of the United States had a lower accident-frequency rate than either the metal- or coal-mining industry as reported for 1942.8 However, the quarry industry ranked eleventh in 15 major industries during 1942 in lost-time accident fre¬quency; metal mining ranked fourteenth and coal mining fifteenth.

Jan 1, 1950

By Alexander E. Morrow

Oxygen breathing apparatus for use in mines was introduced to the United States in 1907. Despite their intended purpose of safeguarding lives, the apparatus led to the deaths of many men because of inherent or developed defects in the equipment, lack of training,, physical shortcomings of wearers, and improper procedures. The Bureau of Mines pioneered in research and training to curb logs of life among users of such apparatus and promoted development of safer equipment and procedures. As a consequence, deaths have been far less frequent. In 1944 the Bureau issued Information Circular 7279, Loss of Life Among Wearers of Oxygen Breathing Apparatus. That publication listed the case histories of 26 deaths that had occurred since the introduction of such equipment to American mining. The author, the late G. W. Grove,3/ asserted that further loss of life could be avoided if good equipment were used, teams were properly trained, and the basic principles of safe procedure were followed. This publication is a sequel to I.C. 7279 and contains information on eight deaths among wearers of oxygen breathing apparatus that were overlooked in the original compilation. It also describes the single death that occurred since I.C. 7279 was published.

Jan 1, 1959

By C. K. Eilerts

Knowledge of the phase relations of the fluids that exist in the porous spaces of rocks constituting natural petroleum reservoirs and of the behavior of these fluids under various field conditions of operation is essential to the conservation of petroleum and natural gas and to their efficient recovery. The problem of determining whether these fluids axe in the liquid or gaseous state send of recognizing the transitions that may take place as the material in the reservoir is subjected to different conditions of pressure and temperature confronts many producers today, especially in certain fields. The subject has grown rapidly in importance since the discovery of and production from deeper reservoirs that have correspondingly higher pressures rind temperatures as compared with shallower

Jan 1, 1938

By E. G. King

An earlier Bureau of Mines report4 provided low-temperature heat-capacity and entropy data for three sodium vanadates. This report continues the study of vanadates by presenting analogous data for three crystalline calcium vanadates - calcium metavanadate (CaV206), calcium pyrovanadate (Ca2V2O7), and calcium orthovanadate (Ca3V208). No similar data for these compounds have been published previously. MATERIALS All three vanadate samples were prepared by the Bureau of Mines by heating stoichiometric mixtures of reagent-grade calcium carbonate and vanadium pentoxide.5 Calcium metavanadate was prepared at 610° to 660° C. A stoichiometric mixture was heated for 17 days with intervening grindings, mixings, and adjustments of composition, as shown necessary by chemical analysis. The final analysis gave calcium oxide, 23.48 pct. (theoretical, 23.57 pct.) and vanadium pentoxide, 76.32 pct. (theoretical, 76.43 pct.). The sample also contained 0.11 pct. acid-insoluble matter. The X-ray diffracton pattern showed no lines of free calcium or vanadium oxides. No X-ray diffraction patterns were found in the literature for any of these substances.

Jan 1, 1961