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By Sidney Katell

Tonnage oxygen plants are or can be made available in sizes ranging from 150 to 1,000 tons per day. Capital requirements are estimated from $5,400 to $14,700 per daily ton, depending upon size of plant, cycle employed, and purity and discharge pressure of the product. Similarly, operating costs before return on investment will range from $4.80 to $10 per ton. INTRODUCTION Several processes4 5/ that can be used to convert coal to synthetic liquid fuels, synthetic pipeline gas, or hydrogen require high-purity oxygen as one of the basic raw materials. Depending on the and product and its specific use, the oxygen required will be of 95 or 99.5 percent purity. The quantity required, in turn, depends on the process for which the oxygen will be used and the size of the processing plant and will range from 150 to 4,000 tons per day.

Jan 1, 1960

By Mattos J. L. C

Drilling and blasting with explosives in mining operations near communities require careful planning to mitigate socio-environmental impacts. Ground vibration, noise emission, flyrock, and dust dispersion are factors that may trigger conflicts with local populations. However, large-scale operations demand high productivity and intense material handling, making it essential to balance operational performance with impact control. The adoption of best practices, combined with advanced monitoring and mitigation technologies, enables sustainable mining even in proximity to inhabited areas. This study proposes the use of double and triple-deck blasting techniques with large-diameter boreholes (12 ¼” – 311 mm), addressing the sizing of charges and decks, as well as measures aimed at reducing noise perceived by nearby communities. The approach seeks to maintain the use of large drilling rigs already present in the operation, avoiding costs related to premature equipment replacement or expensive alternatives, while minimizing environmental and social impacts and promoting a more balanced and responsible mining model.

Jan 26, 2026

By John W. Vanderwilt

The unpredictable behavior of ground movement and subsidence has complicated the problems that attend the extraction of large quantities of ore. Special studies, particularly relating to coal mining, have yielded such a voluminous literature and so many involved controversial theories that a partial review would be difficult. Limited space makes any kind of a review impractical. The features to be considered cover only a relatively small part of the broad problems of ground movement and subsidence, but it is believed that this small part is critical. The practical aspects are important, since they bear directly on safety of mine workings, on recovery of ore and on dilution of ore in block caving and related systems for extracting large quantities of rock. The ground movement to be described occurs outside the vertical boundaries of a caved block in the area that is commonly referred to as being in the "zone of draw." "Draw" is a term that originated in the subsidence problems related to coal mining, and it is defined by a line drawn from the margin of the area caved underground to the most distant fracture at surface on the same side of the caved area as shown in Fig. I.' A line thus drawn is called the cave line, and its angle with respect to the horizontal is the cave angle or angle of draw. It is understood that the line is taken normal to the limit of mining, and in a vertical plane. The prevailing theories as to draw and angle of draw assume that appreciable movement occurred along the cave line, which has been described as a fracture resulting from the shearing action brought about by the weight of the overlying load. Fig. 3 shows diagrammatically the mechanics of ground movement adjacent to an area of subsidence according to the prevailing theory of draw (A, from Royce2) and, for comparison, ground movement observed in the Climax mine (B). The text in Peele's Handbook2 referring to Fig. 2 does not state the meaning of the "original position of top of workable ore" in the rectangular space above "ore in place," and the arrows are not explained. However, this presentation is most concerned with the zones outside the rectangle. According to the prevailing theory, as shown at the extreme left under A, Fig. 2, the vertical tension cracks at surface change at a shallow depth to shear fractures forming the cave line, and it is assumed that appreciable movement takes place along the cave line toward and into the subsiding caved block. The mechanics of ground movement observed in the Climax mine, as shown under B, Fig. 2, does not accord with the prevailing theory, particularly as regards the cave angle and draw. The vertical tension cracks seen at surface die out at depths of 150 to 225 ft. and shear fractures do not develop. Movement is confined at surface to a mantle of rock 50 to roo ft.

Jan 1, 1949

By Michael J. Cruickshank

A workshop to examine recovery systems for selected strategic and critical materials in the U.S. National Seabeds for the National Defense Stockpile in the 21st Century was held in Hawaii September 26-28, 1991, sponsored by the National Science Foundation and the Marine Mineral s Technology Center. The National Defense Stockpile of critical and strategic mineral commodities is presently in a deficit position of more than 7.5 billion dollars. Current domestic reserves of some commodities are limited or nonexistent. As defined by the U.S. Bureau of Mines, "Reserves are select resources . . . which at the time of classification, can be mined at a profit." Occurrences of these minerals have been discovered offshore within U.S. jurisdiction. If the technology could be developed to convert these resources into usable ore reserves, our dependence on foreign ores could be greatly reduced. Preliminary estimates indicate that a ten-year program of ore reserves definition, with appropriate technical developments to demonstrate a recovery system, could cost less than half the amount authorized for stockpile acquisition in FY 1989 alone.

Jan 1, 1991

By Marcos Vieira, Gil Vilela, Wanderson Silvério, Livia Faustino, Pierre Fernandes

New global industry standards and regulatory changes regarding mining tailings management are driving installation of tailings filtration plants to decommission existing tailings dams and implement dry stacking. Target of this project was to reduce ultrafine slime tailings deposition. Previous investigation at Samarco concentrator has showed a 35% decrease in tailings filtration throughput when feeding a mix of 95% flotation tailings with 5% slime tailings (compared with 100% flotation tailings), also worsening geotechnical aspects such as material workability during dry staking. Industrial trials using a proper filter aid at tailings filtration plant feeding a mix of 94% flotation tailing and 6% slime tailing (equivalent to 30% of total slime generation) have provided filtration performance maintenance (throughput and cake moisture), and dry stacking the dewatered material. Results achieved will enable life expansion of existing slime disposal structures, as well as potential life of mining extension. Furthermore, reagent chemistry influence is discussed by the light of geotechnical aspects, which has been showing improved KPIs, such as workability, compressibility and permeability.

Feb 1, 2025

By Gordon E. Frantti

Under the auspices of the Geophysical Committee of Michigan College of Mining and Technology, an investigation was made in Michigan's Upper Peninsula to obtain geophysical data related to the regional subsurface geology in the area covered by Paleozoic sediments. The area surveyed includes that portion of the Upper Peninsula which lies between R18W to R26W and T41N and T49N, covering approximately 1300 square miles. On the index map, Fig. 1, it is represented by the cross-hatched zone west of Munising. Four of the five sites of detailed investigation are indicated by the letters A, B, C, and D. A detailed gravity and magnetic survey had previously been conducted by J. G. Wilson near Perkins, 8 miles north of Rapid River, on a local anomalous area. Results of his work, which showed a large positive magnetic anomaly associated with a gravity anomaly, aroused interest in the possible economic significance of the formations underlying the Paleozoic sediments in this part of the Upper Peninsula.

Jan 1, 1956

By Gopala N. Krishnan

The most promising candidate for the recovery of alumina from non-bauxitic sources is the leaching of clay by HCL acid followed by crystallization of aluminum chloride hexahydrate (ACH) by hydrogen chloride sparging. Hydrothermal precipitation of boehmite ( ?-A100H) from aluminum chloride solution will simplify the process, will reduce energy consumption and will eliminate corrosion problems involved in calcination of ACH to obtain alumina. This report summarizes the results of Phase I of a program to study the precipitation of boehmite from AlC13 solutions. The amount of boehmite precipitation from dilute A1C13 solutions (5 wt%) is . negligible below 200°C. Above 200°C the precipitation increases with increasing temperature approaching 40% at 300°C. Addition of HCl acid to the dilute A1C13 solution even in small quantities drastically reduces boehmite precipitation. Solution impurities such as Fe, Ca, Mg, or Na substantially promote the precipitation of boehmite. No precipitation is observed from concentrated A1C13 solution (30wt%) representing the leach liquor.

Jan 1, 1980

By P. M. Ambrose

This report describes an accident, which took place in the Chemical Corrosion Laboratory at the College Park, Md., Station of the Federal Bureau of Mines. The accident occurred while Walter L. Acherman, chemist, was performing a routine manipulation during a corrosion experiment involving commercially pure titanium and red-fuming nitric acid. There was a sudden and very violent reaction, and a large quantity of acid was thrown in the face and over the body of Acherman, causing serious injury. L. B. Golden, chief of the Chemical Corrosion Section, was exposed to nitric acid fumes during the ensuing rescue and first-aid operations and died on January 25, 1954. According to the medical report, the direct cause of Mr. Golden's death was pulmonary edema and confluent bronchopneumonia; the contributary cause, was inhalation of fumes from red fuming nitric acid. The following employees of the College Park Station contributed to this report by supplying information on the accident and assisted in the rescue operation: L. B. Golden, chief, Chemical Corrosion Section; T. E. Green, chemist; Robert Warf field, chemist; L. A. DeVivo, laboratory mechanic; D. W. Chalkley, laboratory mechanic; E. H. Neagle, laboratory welder; and R. L. Heath, laboratory general mechanic.

Jan 1, 1955

By Dmitriy Kim, Natalya Ibragimova, Galina Sedelnikova

Gold and copper are lost in flotation tailings in mineral processing of copper-zinc-pyrite ores. Large resources of precious and base metals have accumulated in tailing ponds of Russian plants. Object of the study is the sample obtained from Ural Mining and Metallurgical Company in Russia. The main constituents in flotation tailings are Au, Ag, Cu and Zn with content 1.4 g/t, 12 g/t, 0.66 and 0.5% respectively. The flotation tailings are a refractory material. Gold, as main metal, is fine encapsulated in sulfides, mainly in pyrite. Gold extraction from tailings is 34.0 and 42.7% at P42 and P90 of 0.074mm particle size respectively. In this work heap bioleaching of tailings was studied for oxidation sulfides (pyrite and chalcopyrite) with using mesofilic and moderately termofilic bacteria in acidic solutions. The tailings had low filtration property (< 0.3 m/day) and pelletization was used before bioleaching. Copper containing converter slags flotation tailings and calcium oxide were used as binding material for increasing filtration property of tailings. Copper was extracted in sulfate solution and was precipitated by cementation after cleaning of bacterial solution from iron. Copper recovery was 56.8% at content 61.4% in precipitate. The biooxidation of pyrite was 80%. Cyanidation, leaching with thiourea and heap leaching by cyanide were tested too. Gold extraction from solid bioresidues was 82, 75.3 and 77% respectively. The results of this investigation were recommended for pilot test.

Jan 1, 2014

By Atta Ur Rehman, Kwame Awuah‑Offei

This paper evaluates the effectiveness of similitude theory in predicting the draft of a rubber tire loader’s bucket during initial penetration. The work uses 1:16 and 1:8 scale models of an 18-t capacity load haul dump, scaled with the Buckingham Pi Theorem, to evaluate the prediction of draft and penetration under different operating and different dynamic conditions. The authors hypothesize that the observed relationships between draft and longitudinal penetration and the operating and dynamic conditions will hold true for an upscaled model. Similarly, the authors hypothesized that the results of experiments conducted with the smaller scaled model should predict the draft on an upscaled model. The results show that the relationships between draft and longitudinal penetration and operating and dynamic parameters are similar for both scaled models. Similarly, the draft on the upscaled model, predicted by using the experimental results of the small model, is similar to the measured draft on the upscaled model. The mean difference between the two is 1.71 N with 95% confidence interval of [-3.51, 6.93], which is very good given the average draft is approximately 330 N. Thus, the work indicates that both hypotheses are true for draft. However, the work shows that scaling muck pile particle sizes using the Buckingham Pi Theorem is not adequate to ensure good predictions of penetration. This work provides insights that will help design engineers to acquire useful data on scaled models and use it for various analyses on heavy machinery.

Oct 6, 2021

By James Westfield

Uranium activity has introduced a comparatively new hazard to United States mining. In addition to the hazards common to all mines, uranium mines have a complex health problem of radiation damage. Like many new processes, radiation and nuclear energy can be made to serve man in many useful ways when properly understood and handled; but, like fire, gases, and electricity, their potential dangers must be known and respected, and appropriate precautions must be taken or death may result. Since 1950 the Public Health Service has been conducting basic investigations on exposure to radon and its daughter products and the effect of exposure upon the health of miners in uranium mines of the Western States. The Bureau of Mines assisted in several of these investigations, especially in mines on Indian lands. The studies have shown that a serious health hazard exists from radioactive exposure that might cause lung cancer if continued over a number of years. The Public Health Service report, Control of Radon and Daughters in Uranium Mines and Calculations on Biologic Effects,6/ shows that 55 percent of the uranium mines employing 64 percent of the miners had atmospheric concentrations more than five times the working level now accepted as reasonably safe for industrial exposures. Extensive control measures are necessary to reduce these concentrations to the suggested working level of less than 300 micromicrocuries of total radon daughter products per liter of air.

Jan 1, 1958

By E. C. Lane

This report on properties of commercial motor fuels is the twelfth in a series made in accordance with a cooperative agreement between the Cooperative Fuel Research (C.F.R.) Committee and the Bureau of Mines of the United States Department of the Interior. The first report contained data on motor gasolines sold during the winter of 1935-36.V The -present report, covering the summer of 1941, presents analytical data for 1,857 samples, representing the products of approximately 135 companies. As in previous surveys, these companies include both large and small suppliers. In addition, the Pacific coast is represented by data averaged by the Pacific Coast Technical Group before being submitted, and these data are published exactly as they were received. Conforming to previous surveys, the data cover three groups of samples -- regular-price, premium-price, and third-grade gasolines -- and each group has been aver aged separately. The number of samples, items, and brands comprising each group, exclusive of those of the Pacific coast, are as follows: Regular price, 1,010 samples, 291 items, and 86 brands; premium price, 577 samples, 263 items, and 78 brands; third-grade gasoline, 270 samples 159 items, and 74 brands. The meanings of these terms as used in the surveys are as follows: Sample: The individual supply of gasoline obtained at the filling station and analyzed in the laboratory.

Jan 1, 1942

By Reilly L, Worner H. K

The EnvIRONment process has been developed to treat steel works dust and organic wastes simultaneously. A pelletised feed is fed into a special DC electric furnace, the pellets becoming immersed in a molten slag above a carbon saturated bath. The iron oxide in the pellets is reduced and carburised whilst the organics are broken down to carbon monoxide, carbon dioxide, hydrogen and water vapour. Volatile metals are vapourised and collected in the baghouse. Over two years of trials in a 100 kg DC electric are furnace has brought the process to the stage where it is ready for commercialisation.

Jan 1, 1995

By I. Gombköto, G. Mucsi, S. Nagy, F. Kristály, Á. Rácz, R. Szabó, B. Egyed

"Present paper deals with the investigation of a Hungarian pumice. Grinding experiments were carried out in a stirred media mill for various residence time. Ground samples were tested with laser particle size analyzer to determine and calculate the material fineness (particle size distribution and specific surface area). The lime adsorption capacity was measured to monitor the reactivity. Alkali activated cement paste was prepared using ground pumice with various alkali activators. Cube shaped specimens were produced from the paste and the uniaxial compressive strength was measured at the age of 7 days. The resulted alkali activated material structure was investigated by XRD and FTIR. The results of the experiments show that pumice fineness has strong impact on its hydraulic activity, hence on the compressive strength and the structure of the resulted binder. Relationships between grinding fineness, material structure and strength of the raw and mechanical activated material as well as the alkali activated cement were revealed. INTRODUCTION Pumice is a natural pozzolan which can be used as raw material for cementitious materials in limited portion owing to its low reactivity. Furthermore, due to its mineralogical composition it can be used for developing a new environmental friendly binder, namely alkali activated cements (AAC) which are inorganic alumina-silicate materials with good cementitious properties (Almalkawi et al., 2017; Özodabas and Yilmaz, 2013; Najimi et al. 2018; Yadollahi et al., 2015). Despite being a rather recent research topic, many papers and books have been published focusing on various aspects of alkali activation. There is great variety of raw materials that can be utilized for AAC production. However, primary raw materials are very expensive and secondary materials are heterogenous in composition. Therefore, a more homogeneous and low price silicate would help to balance the properties and cost of resulting cement and easing the way for commercialization of AAC. However, the control of its reactivity is of great importance which can be realized using mechanical activation by grinding (Juhász and Opoczky, 1990; Djobo et al., 2016; Mádai et al., 2015). The goal of present paper is to investigate the effect of mechanical activation of pumice on the properties of the resulted alkali activated cement."

Jan 1, 2018

By N. V. Ramana Murthy

Utilisation of Low-Grade Iron Ore Fines after concentration not only helps in conservation of the mineral wealth, but also substantialsly improves the economics of iron ore mining. There has been need to develop suitable beneficiation process for upgradation of low-grade iron ores towards their rational utilisation. Presently the circuit adopted for processing iron ores has limitations in reduction of alumina. The depletion of high-grade reserves, utilisation of low-grade reserves coupled with in-creasing market pressure for improved product quality necessitates re-examination of the process flow sheets and evaluate alternative or supplemental processing routes. The main objective of the Process amenability studies for utilisation of Low-Grade Iron Ore Fines (-10mm) is to get Pellet grade concentrate with +65% Fe (min), SiO2 1.8% (max), Al2O3 1.8% (max) and other proportionate constituents by adopting suitable beneficiation techniques and to collect the relevant data (Quality and Quantity of the Products) for the process development. In an effort to formulate a conceptual process flow sheet, the Process amenability studies for utilisation of Low-Grade Iron Ore Fines (-10mm), which is lying at a mine site in India, samples were collected and taken up for the study. The efforts of R & D of NMDC are discussed in this paper. Low-Grade Iron Ore Fines (-10mm) sample assayed 60.10% Fe with 3.48% SiO2 Aland 4.48% 2O3from 40 microns to 300 microns. The sample consists of hematite as the chief ore mineral followed by minor amounts of maghemite. The gangue minerals include quartz and ferruginous clay in which quartz occurs as medium grained where as ferruginous clay occurs as fine to sub microscopic size mineral. The economical processing route evolved out of the studies finally could yield a final concentrate constituting 58.63% by weight along with Iron unit?s recovery of 63.51% assaying 65.10% Fe with 1.48% SiO2 and 1.85% Al2O3route that adopted comprises the following operations. Making slurry in a sump pump followed by grinding in close circuit with 48mesh size Screen. The -48 mesh size product was subjected o the Cycloning to remove slimes. The Cyclone Underflow product was subjected to Floatex Density Separation (FDS) to separate fine heavy minerals from the gangue minerals. The FDS Underflow was collected as concentrate. The FDS Overflow product was further subjected with Wet High Intensity Magnetic Separation (WHIMS) to recover more Iron units as magnetics. A conceptual process flow sheet was evolved, which may become the prelude to the subsequent finalisation of the process flow sheet for commercialisation.

Jan 1, 2014

(Under this heading will be published notes sent to the Secretary of the Institute by members or other persons introduced by members) Member, Graduate Colorado School of Mines. Four years&apos; experience in West and Northwest. Two years with American Smelting and Refining Co. Wishes to join field party on geological work, mining or areal, where opportunity will be given to be of direct assistance to chief of party in solution of field problems. Age, 26. Unmarried. At liberty June 1. No. 342. Member, technical graduate, aged 30, with&apos; 7 years&apos; experience in concentrating and mining, desires a position of authority with reliable company. At present employed. No. 343. Member. Ambitious, energetic, tactful engineer, college graduate, married, aged 30, desires location with a large coal mining organization. Seven years with present employers -n middle west; has had broad experience in the past eight years on examination, development and construction; successful record in handling men. Position must carry responsible work and a future. Will go anywhere for proper opportunity. Exceptional references as to reliability, character and capacity for work. No. 344.

Jan 3, 1917

THE shipments of high-grade manganese ore, con-taining 35 per cent or more of manganese, from the mines in the United States in 1926 were slightly less than half as large as similar shipments in 1925, accord-ing to the United States Bureau of Mines, Department of Commerce. The shipments in 1926 by 45 producers amounted to 46,258 long tons as compared with 98,324 long tons by 42 producers in 1925. This decrease was due to the falling off of the shipments from Montana. The domestic production of metallurgical ore in 1926 was 26,530 tons; that of chemical ore, 19,728 tons. Montana was the largest shipper with 5713 tons of metallurgical ore and 17,904 tons of chemical ore. The largest individual shipper of metallurgical ore was the Crescent Mine in the Olympic Mountain Region, Clallam Co., Washington, from which the shipments for the year were 3162 tons. The mine was operated by lessees and reverted to the owners in July, and thereafter to the close of the year no .ore was shipped.

Jan 6, 1927

By Kazuya Koyama

We are studying the hydrometallurgical recycling process of indium from an Indium-Tin-Oxide(ITO) target. For this process, it is necessary to remove Sn(IV) ions from the aqueous hydrochloric acid solutions containing In(III). In this study, the removal of Sn(IV) ions by a potentiostatic electrolysis method was examined. The polarization measurements and potentiostatic electrolyses were carried out under a nitrogen atmosphere. In the Sn(IV) solution, current begins to rise at the cathode potential of -0.26 V vs. SHE, and increases with a reduction in the cathode potential. In the In(III) solution, current begins to rise at a cathode potential of -0.43 V vs. SHE. Metallic tin was electrodeposited without indium electrodeposition at the cathode potentials of -0.30 and -0.40V vs. SHE. More than 98% of the Sn(IV) was removed at the cathode potential of -0.40 V after the electrolysis for 3hrs. Both tin and indium were electrodeposited at the cathode potential of -0.50V vs. SHE.

Jan 1, 2006

By William H. King

The Mercur Dome mine is in the Camp Floyd mining district, Tooele County, Utah (fig. 1). The property lies between 6,000 and 8,000 feet altitude on the southwesterly slope of the Oquirrh Mountains, a short distance west of Mercur, the district settlement. Mining began in the Mercur area in 1870. Operations at the Mercur Dame mine were started in 1937 after several claims had been consolidated into one group. Preliminary examination of the ground by F. H. Gunnell, a Bureau of Mines engineer, disclosed the presence of vanadium in a carbonaceous shale horizon. Rocks near the Mercur Lame property are chiefly sediments of Carboniferous age, including the Madison and Deseret limestones. The main shaft penetrates the Deseret formation to a point a few feet above the 1,000-foot level where it enters the Madison limestone. The flat-lying vanadiferous shale horizon is exposed on the 1,000-foot level near the top of the Madison limestone. The Bureau of Mines development program, consisting of diamond drilling, auger hole drilling, and sampling, was planned to determine the extent and assay value of the vanadiferous bed. Seven diamond-drill holes totaling 300 feet were drilled from the 1,000-foot level of the mine. Eight hand auger holes were drilled in the back of the drift on this level (fig. 2). Assay determinations were made on 74 samples from the drill holes and supplemental channel samples and are tabulated in this report. The concluding section embodies results of metallurgical tests.

Jan 1, 1949

By H. P. Hamlin, W. A. Grosh

Samples of clays , shales , and argillites from 21 locations were subjected to preliminary bench- scale tests for bloating properties , and several samples were tested for ceramic properties . Samples showing favorable bloating properties were further tested in a pilot - plant - scale rotary kiln . Physical characteristics and concrete -making properties of the bloated products were determined . The Decorah shale from one area made a suitable material for a lightweight aggregate ; however , the limestone layers in the formation must be eliminated or the resulting activated lime must be controlled by quenching .

Jan 1, 1963