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By O. S. North

As recently as the late 1920's there Were few indications that a 15-million-dollar-a-year industry would ever grow out of the mineralogic curiosity vermiculite. Today, it is an important industrial commodity, used primarily as an insulating material and lightweight aggregate, but with a wide range of other applications. The quantity of crude vermiculite produced and used in the United States increased 14-fold in the 17 years between 1935 and 1951. The vermiculite minerals are of secondary origin, formed by hydrothermal alteration of an ultrabasic igneous rock, generally pyroxenite, or by alteration of phlogopite or biotite mica or possibly other similar minerals. According to different authorities, vermiculite may originate either by direct hydrothermel means, by the weathering of biotite or phlogopite, or by a combination of these two agencies. Vermiculites frequently occur at or near the contacts of an acid intrusive rock, especially a pegmatite dike, with a basic or ultrabasic country rock.

Jan 1, 1953

By Floyd JM, Bultitude-Paul J

The development of a process for the extraction of antimony from materials produced by Greenbushes Tin Limited has been carried out based on theoretical and laboratory studies. The materials treated have included concentrates of tantalite and cassiterite containing antimony at levels ranging from 0.3% to 2%. Roasting under controlled atmospheres is required to stabilise Sb203 rather than the low vapour pressure metal or higher oxide. Sulphidising additives such as pyrite, pyrrhotite or sulphur give enhanced antimony removal from tantalite and cassiterite at roasting temperatures of 900¦ to 1100¦C. Substantial elimination of antimony to levels of 0.1% or less was Achieved.

Jan 1, 1986

By L. R. Burdick

Sulfur compounds have long been recognized as damaging pollutants of the air. A number of investigations have been made to determine the amount of such compounds existing in the air of various cities; moreover, some study has been given to the conditions affecting the concentrations. This paper summarizes published investigation and includes a bibliography on the subject. The methods of obtaining data have differed to the type of sampling, analysis procedure, hour of sampling, number of locations, and number of determinations made. Sampling methods include both the continuous type, covering a day or a number of days, and what can considered the ?snap? type, covering very short periods. Continuous sampling has, given data representing the average concentration at the location chosen but no information regarding variations from hour to hour, are none that might be said to represent the average for a city. The snap-sampling method, while not giving a true average for any one location or area, has in some instances made available date regarding variations of concentration during different hours of the day and at various locations or zones within the area chosen. Although the sulfur compounds in the air nay include sulfur dioxide, sulfur trioxide, hydrogen sulfide, and organic compounds of sulfur, most investigators report on the basis of sulfur dioxide. This gas unites with moisture to form sulfurous acid.

Jan 1, 1939

By D. Bienstock

Using a nitrided fused-iron catalyst, the Bureau of Mines investigated the Fischer-Tropsch reaction in the oil-circulation process. The nitrided iron was quite stable and permitted the longest run obtained thus far in the oil-circulation process without the need for reactivating the catalyst--3,700 hours of operation. The effects of several operating variables--temperature, pressure, gas-recycle ratio, space velocity, synthesis-gas composition, and synthesis with and without reflux of oil to the reactor--on the production of oxygenates were studied. The importance of removing reflux oil and of high gas recycle in increasing the oxygenate content was shown. A finished gasoline containing 28 percent by weight alcohols was produced. The research octane number (RON) was 92.9 clear, increasing to 98.5 with the addition of one milliliter of tetraethyl lead (TEL). INTRODUCTION The Federal Bureau of Mines has been engaged since 1944 in a research and development program on the synthesis of gasoline from coal. Gasification of coal with steam and oxygen to yield a "synthesis gas"--a mixture of carbon monoxide and hydrogen--is being investigated at Morgantown, W. Va., and the synthesis of gasoline by catalytically reacting carbon monoxide and hydrogen over iron by the Fischer-Tropsch reaction is being investigated at Bruceton, Pa.

Jan 1, 1960

By Ross Goodman, Jean-Luc des Rivières

The Ohio River Tunnel Project encountered multiple unexpected geotechnical challenges which, continuing to develop over time, hampered excavation completion and impacted the cast-in-place final lining technique and work execution sequence for the entire project. The continued degradation of the excavated hard rock tunnel conditions led to a unique, dynamic, geologic setting that forced the project to innovate new and adaptable measures allowing for a conventional cast-in-place liner to be completed in a safe and timely manner and minimize delay.

Jun 13, 2023

By R. H. Storch

"A preliminary examination of the Bi-Metallic molybdenum prospect was made in October 1944, as a result of which it was recommended that a trench exploration project be undertaken on the property. This report presents the information obtained from project work done during June 1945.In its program of exploration of mineral deposits, the Bureau of Lanes has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to the national security and. economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director.With respect to this report, special acknowledgment is due S. H. Lorain, chief, Albany Division, Mining Branch, for aid in preparing the report.The property is situated in the NW1/4, sec. 26, T. 39 N., R. 29 E. about 21 miles northeast of Tonasket. Tonasket (population 643), the nearest town, is a way point on a branch line of the Great Northern Railway. The prospect is reached by a good gravel road through Havillah to Vincent's ranch, about 3 miles northeast of Havillah. From the ranch, an abandoned dirt road extends to the portal of the Moly alit, about 1 mile distant. The mine road could be kept open without difficulty if properly graded and surfaced."

Aug 1, 1946

By M. E. Volin

The Smuggler is one of the mines in the Aspen district, located the central part of Pitkin County, Colo. It was first examined in July 1943 by C. R. Wilfloy, former mining engineer of the Bureau of Mines at Salt Lake City, Utah, in, company with the lessees, R. D. Rohlfing of Aspen and J. W. Vanderwilt of Denver. The purpose of this examination was to sample a mineralized breccia zone that appeared continuous along the contact between the Leadville and Weber formations. These preliminary samples showed that the zone contains low but significant amounts of lead and zinc and that the minerals are partly oxidized and thus not easily concentrated. The mine was examined again in May 1946 by the senior author and William Herron, one of the present lessees of the property. This examination reviewed the previous sampling and recommended investigations by the Bureau of Mines. Sampling and drilling investigations were conducted by the Bureau from October 1946 to February 1947 and again from August 1947 to April 1948. Aspen is the center of a famous mining district that produced over $102,000,000 in silver and lead ores from 1880 to 1918, when a dispute closed down the mines (fig. 1). All of the workings below the Cowenhoven tunnel in Smuggler Mountain and the lower Durant tunnel in Aspen Mountain have been flooded since that time. The Cowenhoven portal now is caved, and Smuggler Nos. 1 and 2 tunnels are the only accessible workings in Smuggler Mountain. The only operating mine is the Midnight, situated 4 miles south of town at an altitude of 9,700 feet.

Jan 1, 1950

By Fradd WP

South Australia pioneered metal mining in Australia and was the main source of copper for several decades. Gold discoveries and mining also contributed significantly to the development of the Colony. Across the State can be seen the holes, the mullock heaps and, in some instances, the remnants of machinery of the past era. In this, the centenary year of the discovery of the Teetulpa goldfield, considered by some to he the most significant discovery of gold in the State, it is appropriate that we should present a paper on the history of gold mining in South Australia. South Australia has not been a major producer of gold with recorded production a little in excess of 15 million grams (15 t). This represents about 0.25 per cent of the Australian total and ranks last of the States of the Commonwealth. The outstand- ing feature of gold production in South Australia has been the succession of short periods of rela- tively high production immediately following a discovery, with payable dirt being quickly exhausted, a fact clearly illustrated by the graph of South Australian gold production (Figure 1).

Jan 1, 1987

By Geoffrey G. Huggins

Discussions are presented of the three phases of the noise reduction program on flight-type coal conveyors. The three phases are identification of noise sources, evaluation of potential noise reduction concepts, and implementation of noise reduction which is intended to reduce conveyor noise to less than 90 dB(A) in the underground mining environment. The major noise sources are impacts of the chain on the tail roller and on the top and bottom decks. A total noise reduction of 11 dB(A) was achieved by using techniques which are applicable to retrofit. These are a vibration isolated tail roller and an isolated wear strip on the return deck. A theoretical model of isolation provided by the isolated tail roller is developed. Appendices are presented which contain information on other potential concepts and additional data generated.

Jan 1, 1976

By R. Duncan Gardner

This paper describing the milling practice at the concentrator of the Harmony Mines Co. is one of a series being; prepared by the Bureau of Mines on milling methods and costs in the United States. For the period February 15, 1929, to June 1, 1929, the concentrator treated 200 tons of copper ore per day containing 3.84 per cent copper and recovered 99.2 per cent of the total copper in concentrates averaging 26.61 per cent copper. Milling practice at the Harmony Mines is in most respects similar to the usual practice at the average flotation concentrator producing bulk flotation concentrates. The exceptionally high recovery is due to a number of minor conditions. These minor details will be stressed throughout this paper.

Jan 1, 1930

By Desmond M. Levins, Reginald K. Ryan

"Removal of radium from uranium tailings would substantially lessen their environmental impact because it would eliminate, or greatly reduce, the hazards arising from radon emanation, leaching of radium, dust dispersal and gamma radiation. A process is described to extract radium from tailings by leaching in 3M Nael solution. The radium can be rapidly leached at ambient temperatures by either multi-stage contact in agitated vessels or washing on a tailings filter cake. Extraction efficiencies ranging from 80 to 94% have been measured for tailings derived from a number of Australian ores.Methods for radium recovery from the leach solution by precipitation, ion exchange and adsorption have been examined. Precipitation as barium/radium sulphate appears to be the most suitable approach. A possible flow diagram for the process is proposed which involves recycle of the saline leach liquor.IntroductionDisposal of mill tailings is the most contentious environmental issue facing the uranium mining industry. The conventional approach to managing tailings is to store them in a dam above ground. Attempts have been made to stabilize some tailings piles by physical or chemical methods. In a few cases, the tailings have been covered with earth and revegetated. However, most tailings piles from abandoned mills are in a neglected state and subject to the erosive and dispersive forces of nature. The cost of remedial action is high. The United States Department of Energy (DOE) has estimated that it will cost up to $130 million to rehabilitate abandoned mill sites in the U.S .A..Environmental authorities are now insisting that uranium mining companies improve their methods of tailings disposal. In the United States, the preferred approach is burial, either in mines or in specially excavated pits. Tailings retention systems as operated in Canada are regarded as storage facilities until an acceptable method of disposal is found. In Australia, the Fox Commission recommended that tailings from the Ranger project should be returned to the open-cut mine. Returning tailings to the mine has considerable merit, but it is not always a viable option. In many underground operations, it is not physically possible to fit all the tailings in the worked-out mine. In other cases, the groundwater hydrology of the mine may be unfavourable."

Jan 1, 1980

By Albert L. Toenges

[During the past few years there has beer trend away from locomotive haulage of coal from the loading point to the preparation plant of bituminous-coal strip, miner to motorized. haulage. The question has arisen whether this is always economical, and the purposes of this investigation is to determine, if possible the economic limit for motorized haulage. The operators of strip coal mines and of open-pit ore mines have shown great interest in this problem, and it is thought that the findings of this investigation will. Provo helpful to them.]

Jan 1, 1938

By W. G. Diamond

Lightweight aggregates have become increasingly important to the construction industry. From 1953 to 1960, the quantity of the aggregates used in concrete block, precast and prestressed concrete, and monolithic structures increased about 92 percent. The present study was conducted in Bureau of Mines Area IV which encompasses the South-Central States of Arkansas, Kansas, Louisiana, Mississippi, Missouri, Oklahoma, and Texas. This is an administrative area and does not delimit a market area or imply an economic unit. Because of the increasing importance of metropolitan areas in evaluating economic growth, significant data showing relationships between growth of the metropolitan areas and the lightweight aggregate industry are included.

Jan 1, 1964

By Jim Sarvinis, Mark Berkley, David Clarry, Jason Berzansky

"Technologies developed to sequester CO2 or use CO2 for enhanced fossil fuel recovery are currently being utilized across the globe. Taxation regimes and CO2 credit trading are becoming drivers for a number of projects. Some mining companies have also identified ancillary opportunity to sequester CO2 in their by-products; recent work in the alumina industry is a prime example. In addition to process plant emissions, mining companies are becoming increasingly aware of their overall carbon footprint, including CO2 generated during the production of utility power. New power plant designs, in various stages of development, include CO2 separation and sequestration techniques. This paper summarizes the state-of-the-art for these technologies; including integrated gasification combined cycle (IGCC) power plants. A concept to use the gasification products as reductant in metallurgical processes is also described. The relevance of technology from power plant designs with post-combustion capture to the processing of off-gas generated in metallurgical facilities is also reviewed.IntroductionGlobalization and international economic growth have led to an increase in energy demand worldwide, and a corresponding increase in greenhouse gas (GHG) emissions. In 2005, 81% of global energy supply came from fossil fuels [1]; and while alternative energy technologies are emerging, it will require many decades to curb society’s fossil fuel dependence. Given the global concern of climate change and its scientific relationship with anthropogenic carbon dioxide (CO2), there is at present great interest in the development of techniques to reduce emissions of CO2. While most of these efforts are related to power generation and energy efficiency, the development of technologies for CO2 capture may offer opportunities in reducing emissions from industrial processes."

Jan 1, 2008

By T. T. Campbell

A survey of the literature eras made covering the use of aqueous non-aqueous, and fused-welt systems for the electrowinning or electroplating of molybdenum metal. The survey was prepared in order to provide background for further investigations directed toward the electrodeposition of pure molybdenum metal from either aqueous or nonaqueous mediums. While a thorough effort was made to cover all available references, a critical review was not attempted nor does this survey pretend to be exhaustive in nature.

Jan 1, 1955

By B. J. Moore

This publication contains analyses and related source data for 256 natural gas samples from wells and pipelines in 17 States. All of the samples were obtained and analyzed during calendar year 1977 as a part of Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free market economies. This survey has been conducted in the United States by the Bureau of Mines since 1917. In late 1965, the survey was expanded to include foreign gasfields. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus, which are described in Bureau of Mines Bulletins 4862 and 576.3 The results of the investigation of the occurrences of helium are published annually to make the information available as soon as possible to the gas industry and the public in general. Nineteen previous publications have presented the results of 11,317 gas analyses prior to 1977. The first three, Bulletins 486,4 576,5 and 617,6 contain analyses and related source data on 5,218 gas samples collected from 1917 through 1960. The other 16

Jan 1, 1978

By Charlotte Abena Benyarku, Albert Buabeng, Eric Stemn

The abstract highlights the increasing use of mobile equipment in mining and its contribution to accidents. The research analyzes injury narratives from Ghanaian surface gold mines to understand the involvement of mobile mining equipment in injuries and explore the use of injury narrative data as a human factors tool. The study identified priority human factor issues, such as operating mobile mining equipment, part removal/installation, and the operator's cabin. The use of Sankey diagrams for multivariable analysis effectively identified specific operator-centered issues that warrant further investigation for improved safety interventions.

Mar 29, 2022

By Charles Will Wright

The purpose of this paper is to present briefly certain preliminary results of the study of mining methods by the United States Bureau of Mines; to show the relative importance of each method in terms of tonnages mined and man-hours consumed; to give to the mining engineers and particularly to the young student of mining a better understanding of the principal mining methods; and to indicate changes now in progress and to present suggestions for improvements in the art of mining. Questions of mine development and details of underground practice such as drilling and blasting, loading, hauling, hoisting, ventilating, pay systems and mine management are omitted, as these have been or will be discussed in other bureau publications.

Jan 1, 1931

By Robert B. Parsons

"With several hoots of the whistle, Canada's fiscal engineers are once again cranking up the income tax locomotive, in an effort to inject new stimulus into a stubborn economy. And once again, additional gears, wheels, levers, and other mysterious part s are being added to the already complex machinery in order to accommodate the new push.This time, a significant new mechanism involves a major overhaul and expansion of the investment tax credit system.Although the shiny new devices have considerable appeal to a certain group of potential passengers, one wonders if all of the renewed chugging and huffing is on the right track.IntroductionAs indicated in Tax Notes in the July 1983 issue of CIM Bulletin , the April 19, 1983 federal bud get introduced a number of new measures which would permit investment tax credits and research and development deductions to "" flow through "" from a corporation to another taxpayer."

Jan 1, 1984

By J. Bootle

Marrow vein deposits will continue to be an important source of valuable minerals. Productivity per manshift is not keeping pace with operating costs. Increased mechanization of stoping operations must be obtained to create greater productivity at a reduced cost per ton. This application of mechanization may be to either present methods or to newly developed concepts. The total mine unit operations will be effected by increased productivity. Two approaches to increasing the mechanization of narrow vein stoping were studied with the intention of increasing stope productivity and decreasing stoping costs. A method of bringing efficient rubber-tired equipment into narrow cut and fill stopes was designed. It proposes to provide stope access by way of a ramp constructed on the stope fill. Impact breaking equipment was studied and specific applications proposed.

Jan 1, 1977