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By D. W. Frommer, M. M. Fine

"INTRODUCTION Laboratory mineral-dressing investigations covered by this report show that ores from Montgomery County, Ark., and Morgan County, Mo., are potential sources of barite and zinc. Fine grinding and froth flotation yielded drilling-grade barite from the former and chemical-grade barite and zinc concentrates from the latter.Samples from these deposits were subjected to a laboratory investigation to develop an economic and feasible treatment. The Arkansas ore, submitted by the Husky Refining Co., consisted of an intimate mixture of the economic mineral and quartz. Fine grinding and fatty acid flotation were utilized to effect a good recovery of a drilling-grade product. The other was a zinc-barite ore submitted by the Rocky Ford Mining Co., Stover, Mo. There was no problem in the recovery of zinc (most of which occurred as sphalerite), but the recovery of barite by flotation was complicated by the presence of gangue carbonates. Ultimately, an excellent recovery of barite was achieved with a relatively new type of flotation promoter, petroleum sulfonate.In recent years, barite has become one of the major industrial minerals as an essential ingredient in heavy drilling fluids, pigments, and chemicals. New sources of this important commodity are always interesting; thus, it is the purpose of this report to present information that may permit commercial exploitation of two deposits not in production."

May 1, 1952

By Robert A. Jankowski, J. Drew Potts

In this U.S. Bureau of Mines study, four underground respirable dust surveys were conducted to determine factors affecting belt entry dust levels and how using belt air to ventilate work areas affected dust exposures. Belt entry dust levels on the surveyed longwall and continuous miner sections averaged 0.59 and 0.26 mg/m3, respectively. The stageloader-crusher contributed an additional 0.5 to 0.9 mg/m3 of dust to belt air, while the feeder-breaker contributed 0 to 0.2 mg/m3 of dust. A 1,000-ft increase in belt entry length or a 200- to 500-st-per-shift increase in production resulted in roughly a 0.1-mg/m3 increase in dust. Using the belt entry as an intake entry on the continuous miner section appeared to reduce dust levels by 0.1 to 0.3 mg/m3 during cutting. Belt air was not used to ventilate the face on the longwall section.

Jan 1, 1992

By Paul. E. Pesonen

Since early in 1940 the Bureau of Mines has been concerned with possible means of utilizing manganese-bearing materials from the Missouri Valley manganese deposit. During the period between July 1945 and August 1947, the Bureau of Mines undertook to complete certain phases of the problem by re-evaluating the results of earlier work and supplementing the findings by additional operations and field studies considered necessary to permit drawing of final conclusions. Distinctive discoloration marks the outcrop of the manganese deposit which is exposed on both flanks of the Missouri River Valley and its major tributaries for a peripheral distance of approximately 523 miles in south-central South Dakota. The apparent magnitude of the deposit, judged largely from observation of the outcrop, had led to much speculation as to its actual value in terms of tonnage and grade. Similarly, investigative work aimed at developing a means of winning a usable manganese-rich product from the deposit had reached no conclusion, except that certain methods showed more promise than others for accomplishing the final objective.

Jan 1, 1948

By Raymond B. Ladoo

Deposits of talc are known in many districts in Canada but at the present time active mining operations are reported only in Ontario . Here three companies are now operating, two of which, George H. Gillespie & Co. , Ltd. , and the Anglo- American Talc Co. , are at Madoc . The operations of the former company are probably the largest and best known in Canada . The writer , in his capacity as an engineer of the U. S. Bureau of Mines , was permitted by this company to make an inspection of its mine and mill in June, 1920 , and study the methods employed . This information was desired for comparison with methods employed in the United States . The following description is based on observation made during this visit , supplemented by data supplied by the company .

Sep 1, 1920

By J. B. Gayle

The Bureau of Mines studied the effects of air oxidation on the recovery of float coal. Both batch-and continuous-type tests were made on six bituminous coals, representing the range in rank of coals now commercially used for carbonization, and on one anthracite coal. The effects on flotation recovery of oxidation at 1000 C for periods up to 50 days were investigated using an alcohol-type frother and a kerosine-pine oil reagent. Two series of release analysis tests were made, using one medium-volatile bituminous coal. Float coal recovery was adversely affected by oxidation in all tests where the alcohol-type frother was used. Conversely, a small degree of oxidation improved recovery with kerosine-pine oil frother for some of the coals in continuous tests. Prolonged oxidation (beyond about 14 days) adversely affected float coal recovery for all coals, the effect being more pronounced for batch-type tests and for tests using alcohol-type frother. Reagent selectivity for the rejection of both ash forming and sulfur bearing minerals was reduced by oxidation. Severe reduction of reagent selectivity required only about 3 days' oxidation for alcohol-type frother but more than 10 days' oxidation when the kerosene-pine oil reagent was used.

Jan 1, 1965

By John E. Husted

Quantities of kaolin in Georgia in-contiguous or single bodies had been established by previous work to be sufficient for an alumina industry. The need for characterization of this kaolin to determine its suitability as an ore of aluminum resulted in the studies described herein. It was determined in an area roughly 7 x 27 miles, known as the Wrens district that approximately 5.9 billion short tons of kaolin averaging 35.55 percent A1203 exist in an essentially continuous clay body. The Macon-Sandersville district consists of discontinuous kaolin bodies averaging 35.28 percent A1203 with an average thickness of 28 feet. Tonnages for this district are not available. One hundred and twenty core samples of kaolin were analyzed for K20, CaO, MgO, Al203, T102, Cr203, Fe203, Si02, P205, and F. The P205 and F were analyzed by wet chemistry methods and the others by electron microprobe. Seventy-nine of the samples were from the Wrens district forty from the Sandersville-Macon district and one from the Andersonville district. Emission spectroscopic analyses were also made to qualitatively determine all elements present for each core. X-ray diffraction studies were made of each core to determine mineral species present. Scanning and transmission electron microscope pictures also are given for each I' core sample. Elevations, overburden thickness, and kaolin thickness are given for each core site as well as map locations. Isopachs for over-burden and kaolin thickness are given for the Wrens district.

Jan 1, 1983

By X. B. Starnes

"INTRODUCTION The Eva Tanguay property is in Crittenden County, Kentucky, about 1 mile south or the village of Mexico, and can be reached from Marion, the County seat, by travellng south on State Highway 91 for 6.8 miles and then turning southwest on State Highway 70 and traveling 2 miles farther.Although the property lies between the Huffaw and Pigmy properties, which together have produced 200,000 tons of fluorspar ore, production from the Eva Tanguay has been estimed at only 1,000 tons. Geological factors on the property indicated the likelihood of an ore occurrence, and the author examined the property in April 1944. Shortly thereafter, the U.S. Geological Survey wrote a report on the property, which was not published. A drilling program was initiated by the Bureau of Mines November 1, 1944, and continued until eight holes totaling 3,137.5 feet were drilled.The holes showed that the Tubb fault system on the Eva Tanguay property is composed of three members, all of which contained commercial ore. The line dividing the Haffaw and Tanguay properties crosses the vein outcrops, causing a part of the ore indicated to be on each property.The mineral rights, which are leased by Robert Frazer of Marion, are owned by Mrs. O. S. Denny and W. C. Bohn, both of Marion."

May 1, 1947

By Joseph S. Coffman

To determine the availability of manganese for metallurgical purposes from selected world resources, the Bureau of Mines evaluated the potential production of contained manganese in concentrates based on the demonstrated resources of 23 foreign and 8 domestic mines and deposits in 9 market economy countries. All but 2 of the 23 foreign deposits are operating mines; none of the domestic deposits are in operation. The demonstrated resources of the mines and deposits used in this study represent an in situ ore resource of approximately 2.2 billion tons," containing 780 million tons of manganese with a total recoverable production potential of 514 million tons of contained manganese in concentrates. The analyses of mines and deposits in this study indicate that about 213 million tons of the contained manganese (41 pct) is potentially available at a January 1981 constant dollar long-run total cost of up to $1.50 per long ton unit (22.4 lb, or 10.15 kg contained Mn), approximately 428 million tons (83 pet) is potentially available at a cost of about $1.75 or less, and 491 million tons (95 pet) is available at less than $3.30. The remaining 23 million tons, which is potentially available at much higher costs (about $8 to $35 per unit), represents the U.S. deposits. On an annual basis, with a cost range of up to $1.75 per long ton unit, the availability from currently operating mines would last at least 80 years based on 1980 world production data. Total manganese production costs are estimated to comprise mining-8 pet, beneficiation-3 pet, transportation-26 pet, and smelting-63 pet.

Jan 1, 1984

By P. Comba

The U.S. Bureau of Mines investigated a hydrochloric (HC1)-calcium fluoride (CaF2) leaching procedure to treat domestic manganese (Mn)-bearing silicate resources. The proposed process is an alternative to high-temperature and energy-intensive extractive techniques. Single-stage leaching with a stoichiometric amount of HCl and a F-Mn mole ratio of 0.2 extracted 96 pct of the Mn when the leach conditions were 50° C, 3 h, and 35 pct solids. Ninety-eight percent of the Mn was extracted during countercurrent leaching at similar conditions. A process flowsheet was developed that incorporated HC1-Cab leaching, excess leach acid utilization, fluoride (F) recycle, and Mn recovery. When the domestic manganese silicate ore was processed, 98 pct of the Mn was extracted, 99 pct of the Cab was reclaimed, and a leach residue was produced that passed the Environmental Protection Agency (EPA) Extraction Procedure (EP) Test for nonhazardous waste.

Jan 1, 2010

By Lung Cheng

The Bureau of Mines conducted laboratory tests to investigate the ease of frictional ingition with frozen (nonrotating) conical bits cutting into sandstone. The number of strikes with a new bit to obtain ignition of a combustible methane-air environment was measured. Tests were made with bits tipped with both tungsten carbide and steel at several bit attack angles (angle between bit axis and sandstone surface) and initial tip angles (included angle at the tip of the new bit). Carbide-tipped bits required more strikes for ingition than steel-tipped bits, by a factor of 7 to 10. With a carbide-tipped bit, the number of strikes for ingition increased by a factor of about 3 if the bit attack angle increased by 10° or if the initial tip angle decreased by 10°. During use, abrasive wear of the frozen bit caused a flat surface to form at the tip of the bit, thereby decreasing the tip angle. As the attack angle increased, however, the new bit involved a smaller wear-flat area whereby, abrasive wear was decreased.

Jan 1, 1987

By R. Carson Dalzell

The use of nuclear fission for chemical process heat offers the special advantage of high temperature, limited only by materials of construction. The process heat may be supplied economically at elevated pressures, since no compression of combustion air is required. For the initial effort in developing a high-temperature reactor, the indirect cycle, using helium as the heat-transfer medium, was chosen. The major problems are the design of high-temperature fuel elements, construction of an exchanger to transfer heat to process streams in the range of 2,500° F., and development of compressors capable of recycling helium at 1,000° F. and above. A conceptual design of a nuclear reactor to furnish process heat for coal gasification has been made. Spherical fuel elements utilizing a graphite structure, impregnated with uranium carbide fuel, were chosen, as spheres offer the possibility of easier loading and unloading of the reactor. Calculations of pressure drop and gas-pumping power for the system are included.

Jan 1, 1959

By V. H. Gottschalk

Sponge iron is a product resulting from the reduction of an iron oxide below the temperature at which the product melts. Commercial grades usually contain 80 to 95 percent metallic iron, 2 to 5 percent unreduced iron oxide, and an amount of siliceous gangue material depending on the pur.ity of the are used for reduction. The reducing agent may be gaseous or solid, and a large variety of procedures have been proposed for bringing the reducing agent into reaction with the iron oxide. Of the proposed procedures, the one that has the distinction of having been in continuous commercial operation for the longest time, from 1911 to date, was developed at a ceramic plant in Hoeganaes, Sweden, and yields? a product that has an enviable reputation as furnace feed wherever special, high-quality steels are made.

Jan 1, 1948

By Jr. Reistle

The tests reported in this paper were made in the East Texas field in the summer and fall of 1932 as a part of the Bureau of Mines study of the operation of flowing wells and reservoir performance; and to determine, if possible, the minimum reservoir pressure necessary to produce the wells in this field by natural flow through different sizes of flow strings. The minimum reservoir pressure that would be required to Maintain natural flow through 2 1/2-inch tubing was determined experimentally for the existing energy conditions in the East Texas field. With the present available data, however, it is impossible to predict accurately or to determine by calculation the necessary energy requirements for maintaining the vertical flow of oil and gas mixtures under all conditions. Although some valuable data were obtained which seem to have application to the solution of problems involving vertical flow, this important research of the petroleum industry is so involved that more study of the complicating factors influencing the flow of oil-gas mixtures through vertical pipes is required.

Jan 1, 1933

By Thomas E. Popplewell

This paper is one of a series being prepared for and published by the United States Bureau of Mines describing the mining and treatment methods and costs obtained in sand and gravel plants throughout the United States. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total costs. It is recognized that publication of total costs might in many instances cause embarrassment to individual operators as well as to the industry as a whole. On the other hand operating costs are essential to the technical discussion and study of the methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue.

Jan 1, 1932

By A. S. Moore

The Bureau of Mines is doing research and development work on removing acid-gas impurities from synthesis gas made directly from coal. Since conventional gas scrubbers, packed towers and bubble-cap columns, are expensive to construct and difficult to operate with viscous solutions, one aspect of the work was developing a compact, agitated, gas-liquid contactor for use with concentrated absorbents. The efficacy of the agitated contactor for absorbing carbon dioxide in diethanolamine increased with increasing solution rate, turbine speed, diethanolamine concentration, and carbon dioxide concentration in feed gas, and with decreasing liquid-gas ratio. It was unaffected by pressure between 200 and 300 p.s.i.g. and little affected by temperature between 115 and 190° F.

Jan 1, 1961

By Walter K. Utt

The U.S. Bureau of Mines conducted research to develop an accurate, real-time, position monitoring and warning system for the vehicles used in surface mining. The product of this research will be technology to reduce accidents and injuries associated with the operation of surface mining haulage equipment. The position monitoring system should reduce accidents related to vehicle position and also increase the efficiency of haulage operations. This research was conducted in preparation for development of an accurate, real-time position monitoring and warning system, which notifies equipment operators when they deviate from a known safe course and are approaching a fixed hazard. A radar positioning system designed for marine applications was evaluated and a series of tests was run to determine the accuracy of the radar positioning system when used in a land vehicle. The radar position determination was compared to surveyed values. Both static and dynamic (moving vehicle) tests were conducted. The static test results were marginal and the dynamic test results were not accurate enough for the position monitoring and warning system. Although a promising technology, the system tested needs to be modified to meet the accuracy requirements of mobile mine equipment.

Jan 1, 2010

By Oliver Bowles

Since 1922 when the Bureau of Mines issued a report2 covering the slate industry in detail, changes in technology have taken place which have an important bearing on the industry. The present paper comprises a record of these changes. Though the value of slate, for roofing, structural, blackboard, sanitary, and electrical uses is generally recognized, it has many competitors. To meet this constantly increasing competition producers are promoting economies in manufacture, and improving processes, thereby lessening costs of production, and are placing on the market products of the highest possible quality, thus creating satisfaction and confidence on the part of the user. This endeavor to place the industry on a better basis, both as regards processes and products, is shown in the recent developments in technology which are presented herein. Valuable assistance in obtaining data for this paper was given by W. S. Hays, secretary of the National Slate Association, N. M. Male, president of the National Slate Association, and Robert Notvest, consulting engineer, Cleveland, O.

Jan 1, 1926

By Y. Miron

Previous studies at the Bureau of Mines outlined the hazards of ammonium nitrate-fuel oil (AN-FO) mixtures in the presence of pyrite-bearing ores. The recent trend in the mining industry to strengthen AN-FO by the addition of aluminum metal raised the question regarding the effect of aluminum in AN-FO in the presence of pyrite-bearing ore. Laboratory work, similar to that done previously, demonstrated that the temperature of a self-sustaining reaction in the presence of AN-FO ore-aluminum is not lower than that for a comparable AN-FO-ore mixture. However, as might be expected from known thermochemical data, once initiated, the resulting reactions between AN-FO, aluminum, and pyrite are much more vigorous than those observed for AN-FO and pyrites alone. The temperature required to produce a self-sustained reaction for the combinations tested in this study is 250°±20° F while in the previous Bureau study, reactions were noted, in some instances, at 150° F. The different pyritic ores may be the cause of this variation.

Jan 1, 1976

By S. R. Rannels, D. E. Rannels

"I. IntroductionThe alveolar surface of the lung is covered by two populations of pneumocytes, type I and type II epithelium. The type I cell, which accounts for most of the alveolar surface area and provides a highly specialized barrier for gas exchange (Rannels et al., 1991), is poorly understood. Although approaches to type I cell purification have been discussed, they have not been applied widely because of the lack of phenotypic markers to monitor isolation procedures (Dobbs et al., 1988; Danto et al., 1992). In contrast, the type II cell has been studied extensively, largely because of the development of reliable procedures for its isolation and primary culture. Investigations based on the use of purified populations of cultured type II cells have provided convincing evidence to support a role for the pneumocytes both in the maintenance of normal lung function and in the response of the lung to injury (for review, see Rannels and Rannels, 1989).While type II cells can be isolated by a variety of approaches, the protocols used most commonly are modifications of the gradient method of Dobbs and Mason (1979) or of the panning method of Dobbs et al. (1986). Purification of the cells based on density gradient centrifugation is reliable and consistent, with yields of 30 to 40 X 106 type II cells per rat of 230 g body weight. Isolation procedures applied to a minimum of three to four rats provide the best results, as lower cell yields are common with the use of fewer animals. The protocol below is designed to obtain a maximal cell yield from the lungs of six rats.II. Materials and InstrumentationMaterialsCalbiochem: DNase I (Cat. No. 260912); Corning: culture flask, 75 cm2 #25115; Costar: culture plate, 24-well #3424; disposable serological pipette #4101; Elastin Products Inc: elastase #E-134; Falcon: cellulose nitrate membrane filter, 0.22 µm, #7105; conical tube, 50 ml, #2070; culture dish, 100 mm, #3003; culture plate, sixwell, #3046; Fisher: BaS04 , #B68-500; NaCl, #5271-3; NaHC03 , #5233-50; Fort Dodge Laboratories: pentobarbital, #1206-lE; Gibco: Dulbecco's minimal essential medium (DMEM), #430-1600EC; Hanks' balanced salt solution (HBSS), #310- 4185AG; Joklik's modified Eagle's medium (JMEM), #410-2300EC; HyClone Laboratories Inc: fetal calf serum (FCS ), # A-1115-L; I CN Biochemicals (Flow Labora tories): amphotericin B, #16-723-48; newborn calf serum (NCS), #29-121-54; try pan blue, # 19 5 5 32; Na/gene: Erlenmeyer flask, # 100-4116C; Pharmacia: Percoll, #17-0891-01; density marker beads, #17-0549-01; Sigma: gentam1cm sulfate, #G3632; penicillin/streptomycin, #P3539; trypsin inhibitor, #T9128; Tetko: HC- 160 nylon mesh, #3-160-53."

Dec 1, 1995

By John C. Edwards

To have the capability to predict the development of localized spontaneous heating within a porous coalbed that is subjected to forced air ventilation or in an otherwise quiescent environment in which buoyancy develops, the Bureau of Mines developed three time-dependent mathematical models, which were used to calculate the temperature increase associated with chemisorption of oxygen by the coal. In each model, spontaneous heating is driven by an Arrhenius first-order reaction between the oxygen and coal. Two models are two-dimensional, and one is one-dimensional. In the first two-dimensional model, a constant-velocity forced convection airflow is specified; and in the other, buoyant flow is allowed to develop in the absence of forced convection. The third model evaluates the airflow from Darcy's law and a specification of the pressure at the surface of a one-dimensional porous coalbed. Numerical computations demonstrated how each model could be used to predict the onset of spontaneous heating when the porous coalbed was subjected to constraints of an imposed internal heat source or a high- temperature airflow. The effects of particle size and coalbed compaction upon spontaneous heating were examined with the third model.

Jan 1, 1990