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By R. E. Siemens, 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 mmaajjoorr 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 process . 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 ( 5,000 - 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 for 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 reagent recovery .

Jan 1, 1983

By Harold M. Smith

The data in this report were prepared to show how Bureau of Mines routine crude oil analyses could be used to evaluate crude oils in terms of common commercial products . The use of Bureau of Mines routine analyses to determine hydrocarbon - type relationships for the gasoline and gas - oil fractions is demonstrated . For this purpose the correlation index , the aromatic profile and the naphthene profile are used to establish reasonably acceptable values for hydrocarbontype relationships . The derivation and meaning of these indications are discussed . These analytical interpretations are applied to a group of high - sulfur crude oils from the Near East , the Permian basin of West Texas , Venezuela , Colombia , California , and other locations , and the resultant data for gasoline , gas oils , lubricating oils , and asphalt are compared by appropriate tables and graphs . Because the Near East crude oils contain higher quantities of paraffins in the gasoline and gas oil ranges , they will yield good , lowsolvency solvents and good kerosine , jet fuel , and diesel fuels , but straightrun gasoline of inferior quality compared to similar products from either West Texas or Venezuelan high - sulfur oils . The Near East oils also should be good sources of lubricating stock . However , when used as stock for catalytic cracking or reforming , the Near East oils suffer by comparison because they are deficient in naphthenes .

Jan 1, 1964

By Carl L. Bieniewski

U.S. molybdenum production increased fivefold from 18.2 million pounds in 1946 to 90.5 million pounds in 1966, and constituted 87.3 percent of the total free world supply in the 1946-66 period. Mining development in other free world countries in the next few years may reduce the magnitude of the U.S. position, although similar development planned for the United States may counteract some of the relative gains by those countries. In 1966 two-thirds of the reported molybdenum consumption in the United States by end uses was as an alloying element in steel. Molybdenum also has important use as an alloying element in iron and high-temperature alloys. Consumption of molybdenum metal for making fabricated parts has increased in the past few years, especially in the space and nuclear industries. Molybdenum compounds are used mainly for making pigment, catalysts, and lubricants. Based on producer reports of shipments of primary products to domestic customers, U.S. consumption of molybdenum increased from 16.5 million pounds of molybdenum in 1946 to 65.6 million pounds in 1966. U.S. molybdenum reserves are now estimated to be 5.9 billion pounds of recoverable molybdenum, an increase of 2.1 billion pounds above previous estimates. Molybdenum ores account for 71.4 percent of the reserves, copper ores for 22.3 percent and copper-molybdenum, tungsten, and uranium ores for 6.3 percent. Several methods for predicting future demand are illustrated and estimates of demand using these methods were made for 1975. Based on present capacities and announced company plans for future developments, estimates of annual production were made for 1967 through 1975 for the United States, Canada. Chile, Peru, and the free world. These data indicate that molybdenum production in 1975 for the free world is expected to be 246 million pounds with the United States producing 68.2 percent and Canada, Chile, and Peru 30.3 percent.

Jan 1, 1970

By A. Matzick

In its work under the Synthetic Liquid Fuels Program the Bureau of Mines has developed on a 6-ton-a-day-pilot-plant scale a continuous, gravity-feed retort far distilling oil from oil shale. The development work covered by this report was done from January 27, 1950, to January 26, 1952, at the ail-Shale Experiment Station near Rifle, Colo. Over 300 pilot-plant tests were made during the investigation. The basic retort developed has been named the Gas-Combustion retort. In this process, part of the heat for retorting of the shale is generated by burning recycled product gas in a combustion zone within the descending shale bad in the retort. Additional heat is supplied by combustion of the carbonaceous residue remaining in the spent shale after the oil has been distilled. Air for combustion is admitted through an air distributor in the center of the bed at about the mid-point of the retort. Hot gas rising from the combustion zone heats countercurrently the descending raw shale and liberated shale oil by pyrolysis of the shale. After passing through and exchanging heat with the incoming raw shale, the oil is condensed as a fog or mist in the gas, which is withdrawn at the tip of the retort. The cool gas is then piped to an oil-recovery system where the oil is separated from the gas in centrifugal separators or other types of mechanical or electrostatic separators. The hot, spent shale below the combustion zone is cooled by heat exchange with recycle gas, which is a portion of the effluent gas from the oil-recovery system.

Jan 1, 1955

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 Ronald S. Conti

The Bureau of Mines conducted a comprehensive laboratory study of the thermal ignitability of various carbonaceous dust clouds with particular emphasis on various ranks of coal dust. The tests were conducted using a new 1.2-L furnace. Autoignition temperatures of dust clouds were obtained as a function of coal volatility and particle size. Dust particles and gas samples were collected by a rapid-sampling system in order to study the reactions involved in preignition and postignition processes. The autoignition temperatures measured in the new 1.2-L furnace were significantly lower and therefore more conservative than those measured previously in the Godbert-Greenwald furnace. The combined effects of thermal and electrical ignition of dust clouds were also studied in the 1.2-L furnace using electrical discharges of varying energies at ambient and elevated temperatures. The minimum spark energy necessary to ignite a dust cloud decreased significantly as the temperature of the dust cloud increased.

Jan 1, 1983

By Fred Leonard

This report is principally concerned with the engineering and economic feasibility of area surface coal mining systems other than draglines. This analysis evaluates shovel/ trucks, shovel/crusher/conveyors, and shovel/rail excavation and haulage systems for an assortment of geologic environments and production rates in the Powder River Basin (PRB) Shovel/trucks, front-end loaders/ trucks, and shovel/crusher/conveyors were studied in a multi-seam, dipping geologic area of the Four Corners Region. The Texas lignite engineering and economic research involved bucket-wheel excavators (BWE), BWE/backhoes, and scraper/backhoe combinations for overburden and coal excavation. The PRE truck/shovel study utilized the most recent computer simulation available in both the design and cost analyses. Detailed engineering analysis, followed by in-depth operating costs (operating and depreciation) result in a complete evaluation of each mining system. Cost comparisons of the different mining systems under similar geologic and production constraints are presented in the report to illustrate the estimated capital investment and production costs per ton of coal and bank cubic yard of overburden.

Jan 1, 1980

By Gary M. Larwood

A study was conducted to determine the amount of transportation equipment required to move 1.2 billion tons of coal in 1985. The Federal Bureau of Mines has investigated a majority of the various practices associated with coal transportation and has gathered information on the regional origin-destination patterns, methods of movement, equipment stocks, rate structures, and operational capacities of the most important modes of coal haulage currently in use. Models employing this information were developed to establish the origin-destination pattern for 1985 coal shipments, estimate practical tonnage capacities for selected coal hauling rivers, develop modal shares for both unconstrained (by river capacity) and constrained cases, and present a range of coal transportation equipment requirements for given sets of constraints. Projected transportation shares for rail ranged from 63.7 to 72.3 percent, and for river, from 8.8 to 16.4 percent. Other coal transportation modes (truck, conveyor, Great Lakes, and tidewater) are expected to retain their historic shares of coal traffic. Equipment estimates were made for 1985 rail and water transportation based on 1973 average and best practice. Average practice estimates ranged from 675,000 to 710,000 hopper cars (100-ton) and 3,100 to 5,940 barges (1,400-ton equivalent). Best practice estimates ranged from 126,000 to 142,000 hopper cars and 1,750 to 3,450 barges. Full implementation of 1973 best practice by 1985 is unlikely.

Jan 1, 1976

Bosworth, T. 0. The Mackenzie oilfield of northern Canada. Petroleum Times, vol. 5, Apr. 30, 1921, pp. 489-491. Jour. Inst. Petroleum Technologists, vol. 7, Oct., 1921, pp. 276-290; discussion, pp. 290-297. Gives location of the field, some of its geology, mode of occurrence and character of the oil. See also Oil Trade Jour., vol. 12, June, 1921, pp. 48-108. Canadian Min. Jour., vol. 42, May 27, 1921, pp. 420-422. Oil and Gas Jour., vol. 20, June 3, 1921, pp. 90-90. Petroleum World (London), vol. 18, June, 1921, pp. 233-2.64, 236-238, 240-241. Bull. Canadian Inst. min. and met., July, 1921, pp. 629-638. Mining and Metallurgy, Oct., 1921, pp. 47-48. Bureau of Foreign and Domestic Commerce. Resources of Balkan and Near Eastern countries. Commerce Repts., Oct. 24, 1921, pp. 488-489. Includes summary of the mineral resources of these countries, mentioning petroleum and allied substances in Roumania, Albania, Anatolia, Mesopotamia, Palestine, Arabia, Persia.

Jan 1, 1921

By Robert L. Lagace

The purpose of the work reported herein was to investigate whether available telephone multiplexing equipment offered a means to rapidly upgrade the traffic-handling capacity of present mine telephone systems and provide for selective calling for safer and more efficient mine operation. Common sense was used to decide whether or not an item could be termed "available." Since conventional telephone gear is not designed to interface pager phones for example, existing shelf items would require adapters to compatibly interface these two types of gear for independent operation over the present single twisted pair used in mines. These and similar small items were allowed, but if a system required any extensive design work to adapt it for the mines, we ruled it "not available."

Jan 1, 1975

The influence of fuel additives on automobile exhaust emissions was studied using engines currently found in the U.S. vehicle population. The fuel additives used in the experiment were four multifunctional additives and one lead antiknock additive. Experimental work was done to determine both the direct effect of the additive per se on exhaust emissions and the influence of Long-term additive effects on emissions with mileage accumulation. Results showed no significant direct or intermediate effect on exhaust emissions for any additives tested. In subsequent experimental work concerned with the long-term or indirect effects of additives, the detergent-dispersant additives were found to have little influence on emissions when used in conjunction with high-quality oil and motor fuel. The lead (tetraethyl) antiknock additive increased exhaust hydrocarbons approximately 12 to 17 percent during a 4,000-mile accumulation period using a base fuel containing 2 ml of tetraethyl lead per gallon. An unleaded fuel was used during a similar accumulation period with no significant increase in exhaust hydrocarbons with mileage.

Jan 1, 1971

By S. H. Lorain

This paper is one of a series on mining methods and costs being published by the U. S. Bureau of Mines. The operations of the Quartz Hill Mining Co., near Dewey, Mont., afford an interesting example of the cost of mining small bodies of direct shipping ore; they also illustrate the effect of the unavoidable periods of unusually high exploration and development costs in this type of mining upon the cost per ton of producing ore. The importance of skilled geological guidance and the necessity of avoiding unnecessary overhead and capital expense at small mines are shown. Operating conditions at Quartz Hill are typical of those in many other mining districts of southwestern Montana. It is believed that the costs presented here may be of value in the preliminary estimation of costs to be expected by conservative operators under similar conditions elsewhere. The information contained in this paper was obtained during a visit to the Quartz Hill mine in August 1936.

Jan 1, 1937

By William C. McLaughlin

In the deep vein mines of the Coeur d'Alene mining district, rock bursts are a potential hazard to the mine structure and underground personnel. Damage repair costs are estimated by one company to exceed $1 per ton of ore mined. The Bureau of Mines, in cooperation with the mining companies, has conducted research intermittently over the past 10 years to help reduce bursts. Onsite inspections of major rock bursts were conducted, and reports were submitted to mine management; these included the geology and geometry of the affected area. The paper discusses the development and improvement of microseismic and surface monitoring equipment. The underground microseismic network, when operated on a regular basis and the results plotted daily, is capable of detecting stress concentration in certain areas. The surface seismographs record rock bursts, blasts, earthquakes, etc., throughout the district and show approximate location, time, and relative intensity of the event.

Jan 1, 1976

By Joseph M. Kuchta

This Bureau of Mines manual is oriented to the technical needs of an investigation of fire or explosion accidents and includes various practical and theoretical information that is needed in analyzing accidents or evaluating conditions that might lead to an accident. It is applicable to accidents in the chemical, mining, transportation, and other fuel-related industries. Specific procedures for conducting an accident investigation are outlined, and various guidelines are given for developing the fire or explosion evidence. Ignitability, flammability, and physicochemical data are presented for over 500 combustible gases, liquids, and solids; empirical and theoretical expressions are also given for extrapolating the behavior of combustible-oxidant-diluent systems to various environmental conditions. In addition, various data pertinent to damage analysis are summarized to facilitate the task of the investigator in developing plausible accident scenarios.

Jan 1, 1985

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 gas 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 method3/ and a continuous 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 Mines. The helium extracted in the plant is supplied to the Army and Navy, and the processed natural gas is sold to a commercial gas company4/. 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 John C. Machisak

INJURY DATA and experience at, coal mines in the United States for 1953 and 1954 are presented in this publication with a minimum of interpretation and comment because of the numerous tables required to afford detailed comparisons between the 2 years. Corresponding tables for 1953 and 1954 follow in consecutive order under the following general sections: (A) General injury experience: Tables 1 to 11: Contain current data on number of fatal and nonfatal injuries, frequency and severity rates, and average severity and time-loss rates. (B) Selected injury data: Tables 12 to 85: Contain current data on causes of injuries, distribution of injuries by part of body injured, days of disability, extent of hand and machine loading, experience by employment and production groups, and various other operating factors and physical conditions related to the occurrence of injuries at the Nation's coal mines.

Jan 1, 1958

The Waukon iron deposit comprises about 210 acres situated 2-1/2 miles north of Waukon, in Allamakee County, northeastern Iowa. The deposits have been exploited intermittently since 1899 and have produced about 67,000 tons of concentrated iron ore. From January to May 1943, the Bureau of Mines investigated the deposit to determine the extent of the ore-bearing material and its amenability to concentration, Seventy-one test pits were sunk. Those that indicated are of a grade high enough to warrant concentration tests were sampled. Average grade of ore was indicated to be 37.02 percent iron and 27.78 percent silica on a dry basis. Beneficiation tests indicated that the percentage of recovery might be relatively low.

Jan 1, 1949

By M. J. Ackerman

This study was undertaken to make a comparison between the cost of mining coal under roof bolt and under conventional timber methods of roof support. Studies were made at 14 mines in Pennsylvania, eastern Ohio, and northern and southern West Virginia. At each mine data were obtained for sections of the mine where the physical conditions, mining equipment, and mining systems were similar. Coal, recognized as one of the basic industrial fuels, is very competitive with other fuels, and management, in order to protect and enlarge its market, must be continually alert to find more efficient methods of production. Continuous production of coal is desired by all operators but never obtained. In mechanized mining the performance and production vary with operating time, which can be interrupted by many variable factors, such as condition of the roof, method of roof support, condition of equipment, water, ventilation, power, transportation, efficiency of operating crew, and supervision.

Jan 1, 1961

By J. C. Holtz

Since 1937 the Bureau of Mines has conducted investigations to provide the technical information necessary to guide the safe use of diesel engines underground in the United States. Coincident with the beginning of the technical study, a survey was made of State regulations pertaining to the use of internal-combustion engines underground.3/ At that time it was found that owing to the known hazards of gasoline locomotives, many States had enacted legislation or regulations limiting or prohibiting their use underground. Some of this legislation prohibited, or could be interpreted as prohibiting, the use of any type of internal-combustion engines in underground workings. After World War II diesel-powered equipment was introduced underground in many States, and pertinent questions are received frequently by the Bureau of Mines about the regulations that permit such applications. Because it was known that new and revised regulations had been made effective in some States in the nearly 20 years that have elapsed since the previous survey,3/ the Bureau decided that a review of the latest regulations in the leading mineral-producing States would be a valuable source of information for those engaged in the production of minerals as well as others. Accordingly, where feasible, this report includes abstracts of State laws and regulations as they affect the use of internal-combustion engines underground, particularly diesel engines. The substance of comments from State officials also are included when these appear to be helpful to interpretation of the regulations.

Jan 1, 1957

By Robert V. Spencer

"This report describes an examination and preliminary exploration of the Magnet Cove Rutile Co. property in Hot Spring County, Ark. The company in 1944 was producing titania for use in-the welding-rod and metallurgical industries but later ceased operations. The deposit appeared to contain potential reserves of rutile ore, and the Bureau of lanes in 1945 conducted an examination designed (1) to obtain samples for ore-dressing tests and (2) to gather information regarding the grade, character, and size of the deposit. This report presents the data obtained by geologic mapping, geophysical surveying, churn drilling, and core drilling. Beneficiation tests are being made at the Bureau of Mines Rolla, No. station, on the samples taken and will be discussed in a later report.The Magnet Cove operation had been called to the attention of the Bureau of Mines, and in view of the potential reserve of titanium-bearing material, it was decided to obtain samples for ore-dressing tests. Churn drilling was selected as a means of obtaining representative samples, and geologic mapping and geophysical surveying were done to throw more light on the nature of the deposit. Subsequently, a few holes were core-drilled.The property contains the NE1/4, W1/2 fractional NW1/4 and 82 acres of the N part of SE of sec. 18, and -29 acres of the SW1/4 NW1/4 sec. 17, all in T. 3 S., R. 17 W., Hot Spring County, Ark. The mine and mill are about 1 mile by graveled road northeast of U. S. Highway 270, a paved road connecting Malvern, 10 miles south and Hot Springs, 12 miles west. The area is served by two railroads, the Missouri Pacific, which passes through Malvern and Hot Springs and the Chicago, Rock Island & Pacific,,has a line connecting Malvern and Hot Springs an passes about 2 miles south of the property. A natural-gas pipe line and an electric power line reach the property."

Sep 1, 1946