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By W. H. Schiffbauer

The U. S. Bureau of Mines has been investigating methods and technology that, when applied to existing continuous coal mining machines, may improve production and safety. Toward those goals, a microcomputer network has been designed that provides automated control and monitoring of all mining machine systems using a single twisted pair cable (two conductor stranded wire twisted together to provide a level of noise rejection). The network also provides -connections for intelligent sensors and systems for navigation and diagnostics. The flexibility of the network is demonstrated in that features can be added and removed without redesigning the whole system. A general description of the network's integration to a Joy' 16CM, Joy 14CM, Jeffrey 102, and a custom built auger machine is provided. The microcomputer networks for the Joy 16CM and the Jeffrey 102 have been installed onboard the mining machines and have been extensively tested at the Bureau of Mines test facility. The Jeffrey 102 system has also been tested in an actual highwall coal seam. Both systems have performed satisfactorily. The microcomputer networks for the Joy 14CM and the Auger Miner have been tested and await installation on the respective machines.

Jan 1, 1990

By Edmund S. Leaver, A. P. Towne, Jesse A. Woolf

Part of the work of the Precious Metals Section is to conduct oretesting experiments on ores selected as representative of various mining districts or areas . The projects are authorized by the Metallurgical Division , and only those ores in which gold and silver or gold or silver constitute an essential part of the total values are assigned to the Precious Metals Section . Such ores include those containing the precious metals only as commercially important ingredients , as well as those containing base metals such as copper , lead , and zinc along with the gold and silver . In many instances the "ore " may be a tailing product of a grade good enough to warrant retreatment , or a concentrate for which it is desirable to develop a method of treatment to avoid the expense of shipment to a smelter . It is evident that in general the greater part of this ore - testing work is done according to standard testing procedure , such as cyanidation, amalgamation, gravity - concentration , and flotation , or a combination of these methods . The standard methods of conducting such tests have been outlined in previous reports of ore - testing studies . However , since the inauguration of this oretesting program 6 years ago , the ores submitted under authorization have become increasingly more refractory to simple methods of treatment. Consequently, a considerable number of the projects completed during the fiscal year 1941 have required an unusual amount of work and in some instances have developed into real research problems . For such ores more complete microscopic and spectroscopic examinations and more complete chemical analyses

Feb 1, 1942

By R. J. Leary

The Bureau of Mines experimental blast furnace was blown with oxygen-enriched blast in combination with natural gas injected at the tuyeres. The air blast was augmented with oxygen to form an enriched blast containing 24,8 pct oxygen, and tests were run at natural gas injection rates of 4.5, 6.0, and 8.3 pct of the air blast. Similar enrichment to 26.8 pct oxygen was tested at natural gas rates of 7.2, 9.1, and 11,0 pct of the air blast. At intermediate proportions of natural gas to oxygen, (1) the fuel rate and the replacement ratio of coke by natural gas were unaffected by oxygen injections and (2) the productivity increased about 4 pct for each I pct oxygen added to the blast. The higher proportions of natural gas to oxygen were less efficient; in return for a lower coke rate, the fuel rate increased and productivity declined. A deficiency in reducing gas imposed a limit upon lower than normal proportions of natural gas to oxygen. Beyond this limit the formation of reducing gas was insufficient to support the rate of metal production. When this condition was encountered, the coke rate requirement for specification iron was abnormally high and production fell off badly. Adiabatic flame temperature is discussed as a means for proportioning oxygen and natural gas additions.

Jan 1, 1967

By Charles J. Haas

The objective of this research was to investigate the interaction phenomena of rock and types of rock bolts to develop design principals for using grouted roof bolts. The investigation was to determine the effectiveness of grouted bolts in resisting lateral displacement and axial separation along fracture planes, and also to determine if grouted bolts eliminate the axial tensile stress near the anchor and the resulting rock fracture. The first year's effort involved defining the post-tensioning response of grouted bars and determining the amount of shear resistance generated by conventional and resin-grouted bolts. A finite-element analysis showed that if the rock and resin grout behave in an elastic manner, the post tensioning of a grouted bar will affect mine roof stability only if movement occurs near the collar. An experimental shear test program revealed that both conventional bolts and resin-grouted reinforcing bars significantly increase shear resistance along fracture or bedding plane when the average normal compressive stress on that plane is low (in the order of 25 psi) and when the bolt is oriented so that the shear displacement tends to lengthen the bolt. An increase in shear resistance is also noted at the higher normal pressure of 250 psi; however, the increase is small compared to the corresponding shear resistance without a bolt. Conventional bolts oriented so that they tended to loosen with shear displacement added no significant shear resistance.

Jan 1, 1974

By R. L. Beatty

IN INDUSTRIAL and domestic daily life carbon monoxide is the most frequently encountered toxic gas. hazardous concentrations of carbon monoxide may be present in the vicinity of many industrial operations, such as metallurgical processes, coke ovens, and fuel- and synthesis-gas producers, and may be encountered in confined spaces, such as dwellings, garages, workshops, vehicular tunnels, and mining operations, in connection with the use of heaters, boilers, internal-combustion engines, after blasting operations, and after fires and explosions. Evaluation and control of the health and safety hazard caused by carbon monoxide depend primarily on the analytical detection of the presence of carbon monoxide and determination of its concentration in air and in various gaseous mixtures. The choice of method of analysis in any particular situation depends on such factors as required accuracy, range of concentration involved, convenience, speed of analysis required, quantity of sample available, qualitative composition of sample or atmosphere to be analyzed, and possible effects of interfering gases. Some of the methods described require only adequate understanding of operational techniques, whereas others require thorough appreciation and skill in applying the principles involved. The instruments and analytical procedures commonly used for detecting and determining carbon monoxide are described in detail, and reference is made to more specialized methods:

Jan 1, 1955

By James A. West

The Quapaw pool is one of the smaller pools in an extensive area of Bartlesville-sand production in the eastern part of Osage County, Okla. (fig. 1). Most of the fields in this area were discovered from 1906 to 1916 and were developed and operated similarly. The Quapaw pool is representative of the area, and much of the developed in studying this pool is applicable to the other reservoirs. This petroleum-engineering study of the Quapaw pool was conducted to provide reservoir data that may aid in more widespread application of the intensive secondary-recovery production methods that have been employed with excellent results in the Bartlesville-sand fields of nearby Washington, Nowata, and Rogers Counties. This study is particularly appropriate because of the intense interest in Osage County fields as areas suitable for water flooding. Water flooding was introduced first into Oklahoma during 1931 in Rogers County, and activity was concentrated in the shallow Bartlesville-sand fields of and Nowata Counties for many years. Although water-flooding projects are now operating throughout the State, the intense activity of the Nowata-Rogers Counties area spread to adjoining counties only during the past few years. Since 1948 the rate of oil production in Washington County (between Nowata and Osage Counties) has increased by 260 percent as a result of water flooding. Currently, leases in eastern Osage County are sought eagerly by water-flood operators, and during the past 2 years the Osage Indian Agency has issued nine permits for water-flooding projects in eastern Osage County. Water-flooding operations are in progress on several projects. Although large oil reserves in eastern Osage County should, be recoverable by water flooding, development and operation of projects will be more expensive than projects in the shallower producing areas to the east. In addition, the Osage County reservoirs appear to be more complex and somewhat more difficult to water-flood successfully. It is hoped that this study will contribute to better understanding of the Quapaw reservoir and, in a general way, to the many similar reservoirs in eastern Osage County.

Jan 1, 1952

By Floyd R. Anderson

Noise control of existing pneumatic drills is difficult and runs into cost, performance and weight penalties. A need exists for a start-from-scratch approach for quiet pneumatic rock drills. The designs based on Leavell Principles which has been successfully used in demonstrating a quiet and vibration free paving breaker, is the concept chosen here. This report shows the feasibility of a quiet stoper for drilling roof bolt holes in coal mines. The work is directly applicable to pneumatic percussive rock drills. The report shows an oscillator based on patented Leavell concepts which results in a vibration free tool and noiseless exhaust. Dynamics of the oscilator is analyzed. Independant rotation of drill rod is provided by an air motor (screw expander) and flushing of cuttings is accomplished by an air ejector in a compact lower housing. The feasibility of no exhaust noise, low drill machine noise, and vibration free casing is discussed.

Jan 1, 1977

By Rolland L. Blake

Petrographic and mineralogical studies were made on unoxidized samples from the Cuyuna and Mesabi districts to study occurrence and properties of the iron phyllosilicate minerals . Examination of 96 thin sections from the thinbedded facies of the main iron - formation of the Cuyuna district indicates that the most abundant minerals are Mn - Mg - siderite , stilpnome lane , and minnesotaite . Reconstitution and recrystallization of minerals has occurred along certain beds , and textures indicate that some minnesotaite apparently formed at expense of stilpnomelane . Three samples of stilpnome lane and one of minnesotaite were concentrated from fracture - fillings within iron- formation . Results of chemical , optical , spectrographic , X- ray diffraction , and differential thermal analyses on these samples are reported . The detection of ammonia in stilpnome lane samples is the first such occurrence reported , and its significance is discussed . New mineral data are presented on greenalite and probable septechamosite from the Mesabi district .

Jan 1, 1964

By C. E. Arrington, A. C. Rice

"Part 1. REDUCTION AND USE OF OXIDANTSSUMMARYA study has been made of the volumetric determination of molybdenum by reduction in the Jones reductor, receiving the reduced solution in a mixture of ferric alum and phosphoric acid, and titrating with standard oxidizing agents. In addition to potassium permanganate, which has long been utilized for this titration, potassium dichromate and ceric sulphate have been found to be applicable. The latter oxidants have been found to be especially useful in the form of dilute solutions for the determination of small amounts of molybdenum. The tests revealed that certain internal indicators give excellent results in these titrations.Reason for These ExperimentsThe following study was initiated with the hope of providing the mining and metallurgical industries with an accurate and rapid technical method for the determination of molybdenum in such low-grade materials as ores, rocks, tailings, steels, and alloys containing less than 0.3 percent molybdenum. Although the experimental work was designed with this purpose in mind, many of the results are applicable to material containing a higher percentage of molybdenum.While the Bureau of Mines had an experiment station in Colorado, considerable analytical work was done on what were then (up to about 1923) classed as rare metals. One of these was molybdenum; and in Bulletin 212, Bonardi's (1) 3/ 60-page chapter covered all methods for the analysis of molybdenum."

Apr 1, 1939

By C. O. Anderson, W. M. Meyers

Since 1922, when a brief report3 on the production and utilization of garnet was issued by the Bureau of Mines, there have been a number of interest—in developments in the technology of that mineral. Greater activity has been displayed in mining, new mills have been erected, and more attention has been paid to improvements in milling so that a more efficient and economical recovery of garnet has been possible. These activities have resulted in larger production; therefore, attempts are being made to broaden the market for garnet abrasives, and to find new uses for the unusual combination of physical properties than this mineral possesses. The writers have recently completed a field study of the occurrence, methods of mining and milling of garnet, and the manufacture and utilization of abrasive garnet products. This preliminary report indicates the most important sources of garnet, the methods by which it is recovered, and the manner in which it is recovered, and the manner in which it is utilized.Chemical and Physical Properties.The term ""garnet"" is applied to a closely related group of minerals which crystallize in the caste forms and possess similar physical properties, although their chemical composition may exhibit greater variation. The chemical composition of the garnet group may be represented by the general formula 3R"" O.R""' 203.3S102, in which R represents the bivalent elements calcium, magnesium, in the manganese state and ferrous iron, R"" represents the trivalent elements, ferric iron, aluminum and chromium in the chromie state. An account of the amorphous substitution of the different bivalent and trivalent elements, specimens whose composition may be represented by a definite formula are rare, the composition of any given specimen generally exhibits treat complexity.

Jun 1, 1925

By E. Lee Bray

"Editor’s note: The editors thank those who make this annual issue possible. A special thank you goes out to the Industrial Minerals Annual Review editor, to the Industrial Minerals & Aggregates Division Technical Committee chair and vice chairs, and to the authors of the individual commodity profiles.Jim Norman, member SME, of Tetra Tech Geo, is the industrial minerals annual review editor. Edgar Blanco, member SME, of Freeport- McMoRan, is chair of the Industrial Minerals &Aggregates Division’s Technical Committee.The technical committee vice chairs include:• NickTushar Gupta and Sallie Gaillard, of the USGS, members SME, agricultural materials.• Abhishek Choudhuryand Xihui Yin, members SME, of Montana Tech and Kemira, repectively, ceramic and refractory materials.• Bobbi Strange and Riddhika Jain, members SME, of Outotec, Martin Marietta and Outotec, respectively, chemical raw materials.• Snehamoy Chatterjee, Alyssa Kendir and Alind Chandra, members SME, of BMT, Universityof Kentucky and Michigan Tech, respectively,construction aggregates.• Subham Verma, Gauran Soni and Freddy Sime, members SME, fillers and pigments.• Kaiwu Huang, Thomas Hilderbrand and Ricardo Santander members SME, of Virginia Tech, Thiele Kaolin and Carbo Ceramics, respectively, sorbents, filters and process aids.• Rhaghay Dubey and William Rapier, members SME, of Outotec and a consultant, respectively, specialty minerals.On behalf of ME readers, the editors thankTwo U.S. alumina refineries produced an estimated 1.5 Mt (1.65 million st) of alumina from imported bauxite in the United States in 2018. The 500-kt/a (550,000-stpy) refinery in Burnside, LA, owned by Almatis Inc. produced specialty alumina used in the abrasives, ceramics, chemical and refractory industries. The 1.2-Mt/a (1.32 million-stpy) refinery in Gramercy, LA, owned by Noranda Alumina LLC produced alumina mostly for use in aluminum smelters but also produced specialty alumina. An upgrade project at the Gramercy refinery to convert 200 kt/a (220,000 stpy) of capacity to produce more profitable specialty alumina was completed in the first half of 2018, and another project to increase capacity was started but a completion schedule was not available. The amount of new capacity was not disclosed, but it would be used to produce nonmetallurgical grade alumina. The 2.3-Mt/a (2.5 million-stpy) refinery in Point Comfort, TX, which was temporarily shut down in March 2016, remained closed throughout the year."

Jul 1, 2019

By B. W. Clyburn

"Coals from the Corporation's Lingan and No. 26 mines are classified as high-volatile A bituminous, with a very low inherent ash and containing a/l essential properties to provide metallurgical coal, with the exception of a high sulphur content. Only through proper cleaning at low specific gravity can the pyritic sulphur fraction of the coal be liberated to an extent where final sulphur meets coking standards. This first section of the paper deals with the operation of a Dutch State Mines heavy-media cyclone circuit to achieve an actual separation in the region of 1.30 specific gravity. A discussion of the parameter of control which must be applied along with an appraisal of the results obtained is included in the paper.IntroductionVery high fluidity and unusually low ash are the outstanding characteristics of coal from Devco's mines in the Harbour seam of the Sydney coal field.However, sulphur content, mainly pyritic, ranges from 1 to 2.5070. To obtain the low and consistent sulphur level required in metallurgical coking coals, preparation at low specific gravity is required .Metallurgical coke is used as the fuel in an iron blast furnace. Its sulphur content largely determines the quantity of slag required to remove it and therefore influences furnace productivity and unit costs.Typical data on the various coal properties of importance in the production of coke are included in Table I. Necessity of Low-Gravity SeparationThe design of any coal preparation plant requires the study of washability properties of the coal to be treated to determine the quantity and quality of coal produced at a given specific gravity along with the difficulty in accomplishing that separation.Their low ash content allows the important washability aspects of Harbour seam coals to be represented by sulphur! specific gravity curves (Fig. I). This particular example indicates that a yield of 54.5% is attained, at a sulphur content of 1.20%, for a perfect separating device operating with a 1.29 S.G. cut point.Material rejected from this separation still contains usable coal, which is recovered as middlings by separating at a higher gravity."

Jan 1, 1980

By D. E. Redmon

Exploration of hidden mineral deposits becomes increasingly important as known ore reserves are depleted. The primary objective in any exploratory program is to obtain enough reliable information to evaluate accurately the potential of the mineral deposit. Constant improvement in equipment and technique has established drilling as one of the most valuable methods of exploration. This paper presents the results of studies of several drilling methods currently used in the search for uranium deposits in sedimentary formations from surface drill sites. Also presented is a description of drilling with wire-line equipment from an underground location in metamorphic rocks. The studies were conducted in the Colorado Plateau area and in northwestern New Mexico and Wyoming. Statements of a general nature pertain to conditions or situations existent in those areas.

Jan 1, 1960

By Richard E. Beane

For several decades, the minerals industry has used leaching techniques to extract metals from rocks whose grade was too low to be treated profitably using conventional metallurgical techniques, and, as of 1972, about 15% of domestic copper production was derived using leaching methods (Beall 1). Increasing interest is currently being directed toward solution mining, particularly with respect to copper, for basically two reasons. In the first place, geological exploration has outlined several copper deposits of large tonnage and 1m', grade which are buried at sufficient depth to preclude open-pit mining which would make such mineral deposits ore deposits. Nevertheless, these occurrences provide significant potential if they could be treated by chemical leaching in situ. Secondly, the porphyry deposits of the western united States, which provide by far the largest percentage of domestic copper, do not terminate geometrically with sharp borders. These large disseminated bodies commonly decrease in grade laterally away from volumes of rock containing ore grade metallization, and the distinction between ore and waste is strictly economic. In order to extract ore grade material from the ground, a significant amount of rock containing sub-ore-grade copper must also be removed which, when placed on dumps, is amenable to solution mining. These two considerations clearly indicate the reasons for the growing interest in solution , leaching techniques--namely the ability to exploit deeply buried low grade deposits and the expansion of reserves in deposits currently under production.

Jan 1, 1977

By Andrew F. Conn

This report summarizes the results from the first year of an anticipated multiphase program to develop improved coal mining equipment which utilize the CAVIJET? cavitating water jet method. This laboratory parametric study demonstrated the advantages of cavitating jets over non­cavitating jets in cutting coal, by producing comparable slot depths at one-fifth of the operating pressure, at better than one-half of the spe­cific energy. These results suggest that CAVIJET-augmented mining devices can be developed with compact, low-pressure pumps. Thus, CAVIJET should be capable of operating with safer, lighter support equipment, while providing all of the advantages (reduction of dust and sparks, reduced damage to cutters) of conventional hydraulic mining methods.

Jan 1, 1976

The hydraulic backfilling of mine tailings has proven very successful at the Homestake Mine in Lead, South Dakota. It allows greater versatility, selectivity and safety in mining. It has also minimized surface subsidence and underground rock movement. The tight filling also eliminates underground fires. This paper explains the hydraulic backfill method used and the problems encountered by so doing.

Jan 1, 1973

By M. Ralchenko, C. Samson, M. Svilans, C. Walsh

"Through-the-Earth (TTE) radio has been proposed as a means of emergency communications in mines. The propagation of a TTE radio signal depends chiefly on the subsurface conductivity distribution. Robust forward models of signal propagation can be computed based on a realistic conductivity estimate. These models can be used, for example, to optimize frequency, estimate signal range, identify zones of anomalously strong or weak signals, or to optimize the position of the above-ground TTE radio unit. A method was developed to determine the conductivity distribution of a mine overburden using TTE radio transmission data. At multiple locations in an underground test mine, we recorded a wideband electromagnetic signal, spanning a frequency range of approximately 500 to 8,500 Hz, transmitted from a vertical magnetic dipole at the surface. Using a finite-difference time-domain forward modeling code, a layered Earth conductivity model that accounts for topography was fitted to the observed data, which minimizes the difference between the calculated and observed attenuations for each transmitter-receiver pair, for each frequency of interest. Introduction and objectiveThrough-the-Earth (TTE) radio has been proposed for emergency underground communications. The most common type of TTE radio is based on the transmission and reception of signals by electromagnetic induction. These signals are in the extremely low to very low frequency range — in practice, between 400 and 9,000 Hz. This technology was historically developed for mine safety, although recently other applications have been suggested, such as communications in civilian infrastructure like high-rise buildings or tunnels, in the military, and even for wireless detonation and activation. In a coal mine, which is a setting of particular importance for TTE radio due to the higher risk of accidents, day-to-day communications can be done through a wired link. High-frequency line-ofsight systems, whose signals cannot penetrate rock, are also used for communications from nonfixed points. Another option is a leaky feeder system, which is a permutation of a line-ofsight system and a wired link, where a partially shielded coaxial cable allows the signal to “leak” (Delogne, 1982). In an incident such as a mine collapse or explosion, a TTE radio system can still provide a communication link, as wired systems can be severed, and line-ofsight systems cannot penetrate through collapsed portions of the mine, or to the surface (Forooshani et al., 2013; Yarkan et al., 2009)."

Jan 7, 2018

By W. B. Boggs

The Noranda smelter was built by Noranda Mines, Limited, from the designs of A. E. Wheeler, consulting metallurgist, New York, for the reduction of ores and concentrates from the Horne mine, and to treat, on a custom basis, ores and concentrates from other mines in the Rouyn district. The smelter is situated at Noranda in western Quebec, about 330 miles directly north of Toronto. Ground was first broken for construction in November, 1925, before the completion of the branch railway into the district, which was not finished until October, 1926. After many difficulties and delays due to the Jack 'of transportation and the severe weather during the winter months, the smelter was started in December, 1927, and the first blister copper was poured on December 17th. The smelter was built throughout in two duplicate units, each with a rated capacity of 500 tons of ore per day. Operations were started with only one unit, and after several months it was found that one unit alone would smelt 1,000 tons of ore per day. At this time only one shaft, No. 3, existed, and its hoisting capacity and the capacity of the original crushing plant were insufficient to supply ore for two units at the increased tonnage. Accordingly No. 4 shaft was sunk and a new crushing plant provided to handle the ore hoisted there. This work was completed in the latter part of November, 1929, and since that time both smelter units have been operating.

Jan 1, 1930

By James Westfield

A brief résumé follows of some of the most recent activities of the Division of Coal-Mine Inspection that have had a favorable effect. on health, safety, and injuries at coal mines: 1. There were approximately 8,510 active coal mines in the United States during 1955. In all, 82,389 regular Federal inspections of coal mines have been made since Public Law 49 became effective in May 1941; 9,823 of these inspections were made during 1955. 2. The Bureau of Mines introduced the revised Coal-Mine Accident-Prevention Course for Supervisors in the coal-mining industry on March 1, 1948. Since that date, 19,455 supervisors and those aspiring to official positions have completed such training conducted by personnel of the Division of Coal-Mine Inspection.

Jan 1, 1956

By Thomas J. Peters

In 1988, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied the 34,310-acre Diablo Mountain (Additional) study area (OR-001-058), in order to evaluate its identified mineral resources and occurrences. The study area lies along the east shore of saline Summer Lake in Lake County, OR, about 145 miles southeast of Bend and 45 miles northwest of Lakeview. The climate is semiarid and temperate, and the study area is almost treeless. Geologically, the (Additional) study area is in a region of fault block-formed mountains and basins, characterized by interior drainage. The area is mainly underlain by unconsolidated Quaternary and Pleistocene lake and playa sediments, which may include subsurface evaporite mineral deposits and resources. Near the center of the eastern margin of the study area are an occurrence of dolomitic limestone of unknown extent, and an area of basalt outcrop totaling 1.5 square miles. A veneer of windblown sand covers about one-half the study area.

Jan 1, 1989