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By E. P. Youngman

By a decree of March 14, 1929,5 the President of the Faitian Repub- lic, considering it to be necessary, until the mining legislation of the Republic shall have been revised, to put into effect the mining law of Decem- Der 4, 1860 (relative to mines, diggings, and quarries), by the authority given in article 55 of the Constitution, declared the law of February 14, 1919, to be abrogated and the provisions of the earlier mining law (December 4, 1050) again to be valid. No concessions were granted under the law of 1919. All citations in this paper, unless otherwise designated, refer to the law of 1930.

Jun 1, 1932

By John A. Breslin

This report summarizes the principal activities and significant results of the Bureau of Mines respirable dust research program since passage of the Federal Coal Mine Health and Safety Act of 1969 and the Federal Mine Safety and Health Amendments Act of 1977. This program has investigated new and improved techniques and equipment to reduce or prevent the formation of dust during the cutting cycle; to dilute, suppress, or collect airborne dust generated during mining, handling, and processing; and to improve the measurement of dust levels for evaluation of engineering controls and for enforcement of Federal dust standards. The report is intended for mining industry dust control specialists and other interested parties. It includes a brief summary of the program to date, a section on future research plans and goals, and a list of publications resulting from the Bureau's respirable dust program.

Jan 1, 1982

By D. E. Wolfson

This report presents 900° C BM-AGA carbonization and related data for coals from the principal beds of Nicholas, Randolph, and Webster Counties, W. Va. Thirty-three samples from nine coal beds in three counties were car-bonized at 900° C in the l8-inch-diameter BM-AGA retort, data from which have been correlated with industrial production. Host of the samples were chemically suitable for metallurgical use, and their coking properties were satisfactory. Except for four of the Lower Kit-tanning samples, the ranges of constituents in the coal seams were 1.8 to 9.0 percent ash and 0.4 to 1.1 percent sulfur, values within the range of accept-ability for metallurgical coals. Coke strength indexes were normal for Appalachian coals of similar rank, and the tumbler stability indexes of the coke ranged from 35 to 57.

Jan 1, 1969

To develop a magnetic levitation transport system that can reduce the cost and improve safety in transporting coal from the face of underground coal mines to the surface. Background Many conventional mining operations use conveyor belts to transport coal from an underground face to the surface of the mine. The Mag-Lev Transport System design replaces conveyor belts with magnetically levitated coal haulage containers moving through a dedicated pipe¬line. Cost estimates, based on current design data, show the Mag-Lev Transport System would have operating and capital costs that are less than or equal to those of an equivalent-capacity conveyor belt system. The safety hazards associated with conveyor belt systems include exposure to moving parts and pinch points, potential fire hazards due to mechanical friction, and the exposure of miners to respirable dust. These hazards would be eliminated or significantly reduced by this novel technology. Approach The Mag-Lev Transport System uses magnetic levitation technology that allows noncontact, frictionless conveyance of a levitated body within a dedicated transit corridor. The mag-lev technology utilizes two types of permanent magnets coupled with an electronic position control system to achieve noncontact levitation. Levitation is provided by neodymium-iron boron (NdFeB) magnets mounted in the base of the haulage containers and inexpensive ceramic-5 magnets located in the bed of the transit corridor. An electronic position control system is used to overcome the inherent instability of the repelling permanent magnets. Proximity sensors, a signal processing circuit, electromagnetic actuators, and fixed ferrous side rails are the major components of the positioning system.

Jan 1, 1994

By L. C. IlsLey

Cooperation between the United States Bureau of Mines and the Safety in Mines Research Board of Great Britain, continuous since 1924, has made possible this and other papers on safety subjects. Grateful acknowledgment is made to representatives of the Board for their assistance in arranging visits to several mine safety stations, and to F. R. Wynne, Deputy Chief Inspector of Mines, for arranging visits to mines in Great Britain and other countries in Europe. During the summer of 1927 the writer had the privilege of visiting the mine safety testing stations in great Britain, Belgium, Germany, and France, in the order named. All of these countries have large coal mines, many of which are rated as gassy. Therefore, when the installation of electrical equipment is contemplated, each of these countries is confronted with the same safety problem as is the United States - the development of electrical equipment that will not ignite gassy atmospheres which through neglect or accident might surround the equipment. The means employed by these countries in safeguarding gassy mines should therefore be of general interest to safety engineers in American coal mines, and it is proposed to give a brief survey for each of the four countries mentioned. The third of these surveys covers conditions in Germany.

Jan 1, 1929

By A. Gene Collins

This report discusses some of the chemistry and geochemistry of cesium and rubidium. Knowledge of the cesium and rubidium content of oilfield waters aids in resolving the origin of waters and petroleum, exploring for petroleum and other valuable minerals, discovering water pollution sources, and augmenting the knowledge of geologic formations. The methods described in this report permit the detection of less than 0.01 mg/l of cesium and/or rubidium in a complex oilfield brine or water. Solvents possessing high-dielectric constants were evaluated for their ability to extract cesium and rubidium tetraphenylboron from oilfield waters and for their flame emission characteristics. Nitroethane was selected and used for the extraction and flame spectrophotometric determinations because it gave the highest sensitivity. Cesium 137 and rubidium 86 were used to determine the extraction efficiencies, which were about 87 percent and 58 percent respectively using a single 10 ml nitroethane extraction from a distilled water matrix. The standard deviation of the determination was 0.0008 mg for cesium and 0.0007 mg for rubidium in the 0.01 mg range.

Jan 1, 1965

Continuous remote sensing of methane concentration in underground mines. Approach A methane transducer, developed as a fixed point rib-or face-mounted operating device, measures ambient levels of methane and produces a signal that is proportional to the measured concentration. How It Works The methane transducer, developed under contract for the Bureau of Mines, uses a catalytic-type sensor which will detect methane concentration. The transducer is mounted vertically, as shown. This type of mounting minimizes dust accumulation on the sensing element, which might cause degraded operation. The unit must not be located in an area where water can continuously drip or run on It. The transducer generates an electrical signal proportional to methane concentration at the sensor. A sensor failure output indicates the status of the sensing element A circuit within the methane transducer detects whether the sensing element is shorted or open. A high signal (approximately 8 Vdc) on the failure output Indicates the sensor element is operating In Its normal range. A low output (less than 1 Vdc) indicates an element fault. The methane transducer, enclosed in a stainless steel

Jan 1, 1982

By James A. Wasson

This Bureau of Mines report summarizes the application of pilot flooding in the evaluation of a potential waterflood project. Aspects of pilot flooding discussed include choice of pilot location, confined and unconfined waterfloods, operational precautions, and comparison of predicted with observed performance. Summaries of published methods of pilot flood data analysis for determination of full-scale waterflood feasibility are presented and their use illustrated for example pilot flood data.

Jan 1, 1974

By M. B. Bransford

A calculation procedure was evolved by the Bureau of Mines for determining the heat-transfer characteristics of dilute gas-solid mixtures in an externally heated tube. The procedure accounts for differences in gas and particle velocities and covers a range of particle sizes. Heat transfer coefficients obtained by the calculation procedure are compared with values reported in the literature.

Jan 1, 1970

By Charles B. Kenahan

Vanadium is subject to only light corrosion in phosphoric acid at temperatures up to 60° C. and has a moderate corrosion rate in this acid at 100° C. It is relatively corrosion resistant in sulfuric and hydrochloric acids up to 60° C, but corrodes rapidly at 100° C. It corrodes rapidly in dilute nitric acid at 35° C. Vanadium is almost inert in 10-percent solutions of formic, acetic, lactic, tartaric, and citric acids; in 9-percent oxalic acid it corrodes slowly up to 60° C. and rapidly at 100° C. Vanadium is resistant to corrosion in substitute ocean water, tapwater, and in 3-percent sodium chloride and 10-percent sodium hydroxide solutions. It is readily attacked, however, by 20-percent ferric chloride, 20-percent cupric chloride and 5-percent mercuric chloride solutions. Vanadium is protected by contact with magnesium, aluminum, and steel SAE 4130 in substitute ocean water, by magnesium and aluminum in 3-percent sodium chloride solution, and by magnesium in tapwater. Vanadium protects copper in substitute ocean water. When vanadium and stainless steel are coupled in sulfuric acid solutions, both metals are usually unaffected by contact, whereas the corrosion rate of titanium in sulfuric acid is greatly reduced by contact with vanadium.

Jan 1, 1962

By G. S. Baur, J. W. Montoya, S. R. Wilson

Beryllium occurs in the Honeycomb Hills area in volcanic tuff similar to the more extensive berylliferous tuff occurring 20 miles east at Spor Mountain , Juab County , Utah . Samples from the two areas have been mineralogically examined to ascertain whether they have similar characteristics . The Honeycomb Hills samples showed the presence of beta- Be ( OH ) 2 , as well as an amorphous berylliferous substance , whereas in the Spor Mountain tuff the beryllium- bearing minerals are hydrated bertrandite and berylliferous saponite .

Jan 1, 1964

By Paul M. Tyler

The colony of French Guiana ( or Cayenne ) is administered by a governor , assisted by a privy council of five members . A council - general of 16 members is elected by French citizens resident in Guiana, and the colony is represented 3 in the French parliament by one deputy . The area is about 34,740 square miles . French Guiana is the largest gold producer of the French colonies , producing nearly $ 1,000,000 worth annually . Considerable prospecting has been done on the bauxite deposits , which are extensive . Copper , iron , lead , and 4 mercury deposits are also reported . In 1931 , 10,000 prospectors for gold were reported as working . The French Government is taking an active interest and has sent a committee of mining experts to explore the region ; no permits are to be issued to individual prospectors while the committee is in the colony . Plans for development of mining industry include consideration of 4,500 convicts and 2,500 natives already in the colony and available for labor .

Apr 1, 1933

By D. Harrington

"In at least three out of every four working faces in metal mines there is no attempt made to cause air circulation other than by use of compressed air, and in at least nine cases out of ten the compressed air is released merely by opening, or partly opening, the valve and allowing the compressed air to escape through open air hose used to convey the compressed air to the drilling machines. Usually no blowers are in use during periods of drilling, as the exhaust from the drill provides cool, comparatively fresh air for the driller; however, in some instances, the compressed-air line is provided with a tea connection, which permits taking air for the drill from one side of the tee, and air for ventilation through a separate hose used as a blower, simultaneously with drilling.Table 1 contains temperature and humidity data as to compressed-air blowers from open end of air hose at 36 working places in eleven metal mines of four States, embracing the mining of gold, silver, copper, lead and zinc ores, and at horizons ranging from 500 feet below the surface to as low as 4900 feet.It is noticed that the ordinary air surrounding the worker at the face gives an average wet bulb temperature of 81.7° F. for the 36 working faces, with 84.7° F. dry bulb and 87.2 per cent relative humidity. The average wet bulb tem¬perature of 36 readings at these working faces of compressed air at the end of the,hose as the air issues from the hose was 67.4° F., or 14.3 degrees lower than the average wet bulb readings of the air of the working places; however, the average dry bulb temperature of the 36 readings of compressed air as it issued from the end of the hose was 79.7° F., or only 5 degrees less than that of the general air (84.7°); the relative humidity was 51.1 per cent as against 87.2 per cent for the surrounding air. Readings were taken in five raises, seven crosscuts, ten drifts and 14 stopes.It will be noted that the velocity or movement of the general atmosphere at each of the entire 36 working faces, was found to be practically imperceptible; this might readily be inferred since compressed air is rarely used on blowers if there is adequate circulation of the general air of the place. Where rook temperatures could be obtained readily, they are shown; it is noticeable that the dry bulb temperature of the air of the working place varies little from the rock temperature, and that the dry bulb temperature of the compressed air as it issues from end of air hose varies only a few degrees from the temperature of the surrounding rock; in some instances the dry bulb temperature of the compressed air as it issued from the end of the air hose was higher than the rock temperature or the dry bulb temperature of the surrounding air."

May 1, 1921

By Robert J. Anderso

Few elements have received more attention and developed greater interest in the last ten years than titanium. The substantially pure metal has been din...ie. cult to isolate, and so far has been little employed oommercially, but the use af alloys and chemical compounds of titanium has increased markedly in recent years. The earlier attempts at preparing pure titanium resulted in various impure forme which, from their metallic appearance, were always mistaken for the metal. Hunter in 1910 isolated pure titanium by the reduction of titanium tetrachloride with sodium. This brief statement is issued by the Bureau of Mines in response to numerous inquiries which have been received concerning titanium. More complete in. formation on the metal may be had by consulting the referenpes appended. The Literature is voluminous and only the more important references are Riven. It has been drawn upon freely in preparing this report; also information was supplied by M. g. Hunter, Arthur Braid, M 1. Schmid, C. M. Johnson, N. B. Hoffman, and de Courny Browne. The pioneer investigator in titanium is A. IL Rossi.

Oct 1, 1922

By Jeffrey H. Welsh

This report presents a study on the use of computerized, continuous remote monitoring systems for fire and explosive atmosphere safety in underground coal mines. The effects of these systems on the safety level in mines are investigated, and the relationship between mine safety regulations and computerized, continuous, remote monitoring is analyzed.

Jan 1, 1982

By D. E. Hirsch, J. W. Davis, Norman G. Foster, F. G. Schwartz

This investigation was undertaken to identify nitrogen , oxygen , and sulfur compounds (polar components ) found in catalytically cracked distillate fuel . It is significant that these compounds concentrate in the sediments and gum that form when the fuel is stored . The polar components were divided in three portions by elution from a chromatographic column filled with alumina . After the hydrocarbons were washed through the column with pentane , a benzene eluted extract was removed followed by an ether eluted extract and then an alcohol desorbed fraction . These extracts were individually distilled in a molecular still and the fractions were analyzed by gas chromatography , mass spectrometry , infrared spectrometry , and elemental and functional analyses . Naphthalene and its homologs , phenanthrene and its homologs , and other compounds such as methyl indene , C₂ quinolines , phenyl indan , and the benzothiophenes , appear in the benzene extracts . Quinolines are the major components of the lower boiling fraction of the ether extract , although carbazoles , acridans , and indoles are present in some concentration . Elemental and functional group analyses of the alcohol fraction indicated 10 percent of the distillate portion was nonhydrocarbon , and in this portion the average molecule contained more than one nonhydrocarbon element . Compounds of such complexity are not well known , and standards for positive identification are limited .

Jan 1, 1963

By Maria I. De Rosa

The U.S. Bureau of Mines performed experiments to determine the hydrogen cyanide (HCN) concentrations and smoke particle characteristics during the combustion of flexible polyurethane foams and other nitrogen-containing materials, for the development of a test parameter. The experiments were conducted in an approximately 2O-L furnace at set furnace temperatures of 250° and 1,000° C for a 14-min duration, with an airflow through the furnace of 10 L/min. The variables studied as a function of time were the gaseous and aerosol HCN concentrations, the smoke particles average diameter (dg) and particle concentration (no), and the product of the smoke particle diameter and concentration (dgno). Carbon monoxide, carbon dioxide, and oxygen concentrations, sample mass weight loss, and furnace temperatures were also studied; analyses of nitrogen and cyanate content of the material were carried out. Results show that dgno correlates directly with the HCN concentrations, which depend on the nitrogen and cyanate contents of the material.

Jan 1, 2010

By Jean M. Kenney

Frequencies of haulage-related accidents in metal and nonmetal surface mines for the years 1988 through 1990 were investigated and compared with those of non-haulage-related accidents. This study was part of the U.S. Bureau of Mines program to improve mining haulage safety. Data were obtained through the U.S. Bureau of Mines Accident Data Analysis (ADA) program. The chi-square test was used to compare frequencies of haulage-related and non-haulage-related accidents for each of the following variables: degree of injury, age, total number of years of mining experience, and shift time. Significance was determined for degree of injury between haulage-related and non-haulage-related accidents. Age of injured did not vary significantly between haulage-related and non-haulage-related accidents, but total number of years of mining experience was found to be significant. Shift time for the accident proved to vary significantly between haulage-and non-haulage-related accidents. Events causing injury for haulage-related accidents were tabulated, and the most frequent determinants of haulage-related accidents were identified. Accident descriptions for both fatalities and permanent disabilities were studied, and the primary causes of these accidents were identified. These findings suggest that haulage-related jobs are among the most dangerous when considering accidents experienced by all workers in the metal and nonmetal surface mining work force.

Jan 1, 1993

By W. E. Webb, R. H. Church, W. G. Hopkins

The development of systems for location of miners who have become entrapped following a mine disaster has been one of the major research goals in the Bureau of Mines. This study details the preliminary development of such a system. Current technologies for locating trapped miners from the surface are either simple direction, finders or time difference pulse systems that have accuracy Limitations. Developing technologies using full vector field measurements at several receiving points are currently being studied. The necessity of measuring field strength with great accuracy can be a drawback in these systems. A system that operates with continuous wave radio signals, whose phase differences can be measured accurately even in weak signal conditions, greatly improves the location accuracy. A microcomputer would be used, in conjunction with the system, to gather and manipulate the data to automatically pinpoint the location of the trapped miner. Comparison of this system with existing technology indicates a favorable accuracy/complexity ratio for the phase difference of arrival technique.

By Irving Hartmann, John Nagy

As part of a program designed to promote safety in industrial operations , the Bureau of Mines has been investigating the explosibility of numerous powdered products and dusts and studying means for the prevention of dust explosions . In a previous paper the results of a study of the inflammability and explosibility of metal powders were published . This report summarizes a similar study which has been made on various powders used in the plastics industry. The work was undertaken to provide information for a subcommittee of the Dust Explosion Hazards Committee of the National Fire Protection Association, which was charged with preparation of a code for the prevention of fires and dust explosions in plants producing or processing synthetic resins and molding compositions . The production of powders and generation of inflammable dusts are inherent in one or more steps of the manufacturing process of many resins and molding compositions, and control of the dust hazard is a major problem in the plastics industry . In the preparation of phenolic resin molding powders, for example , the solid synthetic resin is crushed and pulverized , and then blended with ground wood flour , cotton flock, or other fillers , as well as with coloring pigments . This raw mix is then passed through compounding mills , from which it emerges in the form of homogeneous sheeted stock, which is crushed , ground , and graded to form the molding powder . The number of major dust explosions in the plastics industry has been limited, but numerous small explosions have occurred, and in view of the ever -increasing volume of production the potential explosion hazard must be considered a very real one . Fortunately, this fact is realized by several manufacturers of plastic compounds , as well as by insurance companies , who are taking precautionary measures against possible accidents and during the past year or two have submitted numerous powder samples to the Bureau of Mines for explosibility tests .

May 1, 1944