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By C. C. Merrill

Columbium, tantalum, titanium, and zirconium are present in solid waste products generated by the chlorination of rutile used for production of titanium tetrachloride (TiC14). The columbium and tantalum were separated from titanium and zirconium by liquid-liquid extraction techniques using a secondary amine. Salts of these elements are in a leach liquor produced by water leaching of mineral waste from the chlorination of rutile. This waste, produced at the rate of approximately 50,000 tons per year, is about 40 wt pct water soluble. Leach liquors, separated by filtration, were further separated into a solid fraction and a liquid fraction by pressure hydrolysis, The solid fraction containing Cb, Ta, Ti, and Zr was dissolved in HC1-HF and used as a feed solution. Columbium and tantalum were removed from the organic extractant with 1 [N] HC1. A miniature 10-stage reactor showed that the columbium and tantalum present in solution could be separated with a continuous flow.

Jan 1, 1972

By G. L. Oldright

This paper is the first of a series that is to appear on smelting in the lead blast furnace. The objects of this investigation are to determine the conditions obtaining within the blast furnace by direct experimentation, and to correlate the behavior of the furnace at various times with the main factors governing the operation of the blast furnace, and metallurgical losses. ACKNOWLEDGMENTS The writers wish to express their appreciation to the management of the International Smelting Co. at Tooele, Utah, to Mr. J. O. Elton, the general manager, and to Mr. A. B. Young, his assistant, for their broad-gauge policy that has made possible the securing and publishing of these data. For the staff at Tooele, acknowledgments are made to Messrs. B. L. Sackett, general superintendent, Carlos Bardwell, assistant general superintendent, S. Jacobsen, blast-furnace superintendent, H. M. Rockwell, assistant blast furnace superintendent, and J. O. Welsh, superintendent of the general research, for the spirit of cooperation they manifested in carrying out this work. Mr. C. Reish, a member of the research department, was detailed by, the company to assist in this' work and his whole-hearted assistance has been found invaluable.

Jan 1, 1929

By D. J. Bauer

Solvent extraction techniques were used to determine the extraction sequence of yttrium and the rare-earth elements in an amine solvent extraction system. Single-stage extraction with Primene 81-R resulted in separation factors of 3.8 between yttrium and dysprosium and 25 between yttrium and cerium. Yttrium was concentrated in the aqueous phase. EDTA and DTPA, as aqueous phase counterextractants, enhance separation factors in mine-rare-earth sulfate systems. Yttrium separation from heavy rare-earth elements exhibits marked sensitivity to the position of yttrium in the selectivity scale of the rare-earth elements with the sequestrants. Yttrium-ytterbium separation is more effective with EDTA, whereas yttrium-dysprosium separation is more effectively increased with DTPA.

Jan 1, 1963

By Jr. Oitto

A polyester-type resin and deformed-steel reinforcing bars (rebars) were used in to strengthen and to stabilize bolted, fractured wall rock along pas 1:'y. in a western gold mine. Reinforcing bars were placed in boreholes drilled into fractured rock and then were surrounded by resin pumped under pressure into the holes and intersecting fractures until the wall rock was thoroughly impregnated. Pumping and injection equipment and infusion procedures are described. Visual examinations for movement in bonded and adjacent unbonded rock were made for 3 years. Fractured walls containing resin-rebar installations were strengthened. The results suggest that resin-rebar support can be used advantageously and economically in repairing fractured or broken rock when compared with rock bolting or timbering.

Jan 1, 1965

By A. W. Khair, S. J. Jung

"A fundamental study of fragment size distribution and characteristics of fracture pattern is presented for the dynamic penetration of a conical bit into coal block. In this paper, damaged zones during crater formation and fragment size distribution were studied. Bit with a sharper tip angle and a smooth body configuration performed better penetration. Results suggest that in coal cutting the trend should be toward the face cleat direction using a sharper angled tip bits which consumes less energy for an optimum range of penetration depths, thus attaining maximum cutting efficiency and reducing fine fragments.1. INTRODUCTIONMuch research in the past has been done on energy requirements and mechanism of energy dissipation for ideal rock fragmentation in cutting process. However the mechanisms of energy dissipation or failure criteria for rocks in cutting process in order to evaluate the efficiency of energy requirements in specific rock fragmentation is not well understood. The formation of a crater in rock under the impact blow of a bit has been observed experimentally (Hartman, 1959). It is known that directly beneath the edge of the bit the rock is crushed into fine powder, toward the sides of the crater it chips out into relatively large fragments. (Sikarskie & Cheatham, 1973). Singh et al. (1967) investigated the cratering process under the two different conditions of static and dynamic loading. They found that the amount of energy consumed per unit volume of crater is unequal for the two different loading conditions. A complex network of fractures often extends downward and laterally into the rock below the bit. The surface of the specimens showed that the dynamic loading damaged larger area then the static loading."

Jan 1, 1989

By G. H. Hopkins

Like most industries, the refining industry has in recent years been confronted with the problem of a decreased martin of profit, due both to a general lowering of prices and to rising costs. This has resulted in accelerating a program of increased efficiency an evidenced by improved methods and the installation of equipment designed to affect a number of economies hitherto regarded as unimportant. Perhaps the most important of these has been that of fuel economy for, as is not often realized, a refinery consumes about one-tenth as much fuel as it produces. A recently completed canvas., made by the Bureau of Mines for the purpose of determining the trend of fuel consumption at refineries in the United States, showed the following outstanding points, (1) a decrease in the use of oil for fuel in 1926 of approximately 4,000,000 barrels as compared with 1925; (2) a small decrease in the use of coal; (3) a material increase in the use of gas, both natural gas and refinery gas; and (4) a considerable increase in the use of petroleum coke.

Jan 1, 1927

By Edward W. Parsons

The explosive-expansion center-hole anchor was designed and developed for the specific purpose of use as a component of an instrument system that measures differential ground movement within a small drill hole in rock. Such anchors should have an unobstructed center hole, should be installed without a twisting action which could tangle connecting wires, and should be capable of being installed at depths in excess of 100 feet. The anchor has a thick-walled center tube and a thin-walled outer tube. Low-energy detonating cord, wrapped around the center tube and detonated with a mild end primer, expands the outer tube to produce anchorage. The explosive-expansion center-hole anchor can be installed easily in drill holes of any inclination but cannot be installed under water. Centering of the anchor is critical with regard to its subsequent holding power. The anchor is safe to make and handle.

Jan 1, 1965

By P. Yant, A. C. Fieldner

"IntroductionIn its investigations relative to reducing the hazards of carbon monoxide poisoning, the Bureau of Mines recently had its attention drawn to a compound2a sold under a trade name for which claims are reported to have been made regarding its efficacy in reducing that type of poisoning in automobile garages. Accordingly, some of the product was obtained and analyzed for its power to absorb, oxidize, or destroy carbon monoxide; and the results are herein reported.Description of ""Compound"" (quoted from manufacturer's circular)While the circular does not actually state that the ""compound"" protects against carbon monoxide, the inference is therein, because each of the two following quotations is below these respective headings; ""Carbon-Monoxide Poisoning,"" and ""Chronic Gassing Among Garage Workers.""The ""compound"" holds chlorine and oxygen gases in solution with formaldehyde, which unites with the hydrogen to form hydrochloric acid., giving an over-supply of oxygen which burns up carbon just as a piece of wood is burned in the fire. The formaldehyde in the composition of the ""compound"" is a great affinity for ammonia and hydrogen sulphide."

Apr 1, 1924

By Will H. Coghill

Titanium is a well-known component of bauxite ores, sometimes occurring in sufficient quantity to mace its recovery worth considering. This question has been raised by some of the companies lixiviating bauxite ores. At the East St. Louis plant of the Aluminum Ore Co., a subsidiary of the Aluminum Co. of America, the waste sludge discharged daily contains over 75,000 pounds of Ti02. The sludge is all through 20-mesh, and a large proportion is slime. A supple of the waste was deslimed so that a gravity-concentration test of the "sand" could be made. The Aluminum Ore Co. cooperated in the work and made the chemical determinations In order to anticipate the results of table concentration a series of specific gravity fractions (float-and-sink) was made with heavy liquids. Acetylene tetrabromide was used for a density of 2.95, methylene iodide for 3.33, and thallium formate for 3.78, and the double salt of thallium formate-malonate made the separation at slimed sample appears in Table 1.

Jan 1, 1928

By R. Pakalnis, Richard P. Curtin, Lewis A. Martin

Instrumented cable bolts developed at the Spokane Research Laboratory of the National Institute for Occupational Safety and Health were used in conjunction with existing ground control to monitor rock mass loads at various field sites (T.G. Soda Ash, Getchell, Meikle, SSX, K-2, and Stillwater). Axial and shear loads were determined by strain gages to levels of instrument accuracy of ±5 N or ±5 microstrain as these loads were transferred to the instrumented cable bolts. These gages were 12.5 mm long and embedded into a remanufactured king wire that replaced the conventional king wire. Cable bolt performance, quality of grout, and installation techniques were also assessed. By using instrumented cables, a mine operator can determine axial load along the cable at predefined gage locations. By monitoring load on and displacement of the rock mass, more effective ground support can be selected and installed, which will lead to safer working conditions for miners.

By J. E. Zeilinger

The technical feasibility of using energy from explosive ignitions of coal dust to pump water was .demonstrated in an exploratory investigation. Ignition of small amounts of pulverized coal that were dispersed in air over columns of water pumped up to 5.3 gallons of water per cycle when operated against a head of 30.75 feet. Water displacement was accomplished by either manual or automatic operation through a single cycle, and by automatic operation through a continuous series of cycles of I-minute duration. Operating through single cycles, slurries containing up to 3 pounds of coal and 4.6 gallons of water were also pumped. Possible uses of an efficient coal-fired pump would include pumping water for irrigation purposes, removing water from mines, transporting coal from mines in the form of a slurry, and pumping water to elevated reservoirs at electric powerplants so that it could be used to generate electricity during peak periods of demand.

Jan 1, 1966

By Charles L. Kimbell

Available statistics on 1989 worldwide consumption of selected nonfuel minerals shown in table 5 show increases for 11 of 14 listed nonfuel mineral commodities with 1 unchanged from the 1988 level, a departure from the pattern of the past 2 years, in which each of the listed commodities registered gains. The 1989 results, however, were better than those for 1986 when only seven listed nonfuel mineral commodities recorded gains with one un- changed from 1985. Consumption of the two ferrous metal raw materials listed advanced as functions of increased output of pig iron and crude steel. The increase in iron ore consumption exceeded the increase in iron ore output, suggesting a slight drawdown of world iron ore inventories. The estimated in- crease in iron and steel scrap consumption was slightly greater than the minuscule increase in world steel production, but it is believed that there was little change in the ratio of iron ore to scrap in steel plant feed on a global basis.

Jan 1, 1992

By Benjamin Petkof

Production quarry blasts in three rock types were photographed with a high-speed camera. Analysis of the films showed that step increases sometimes occur in the horizontal velocity of the broken rock. These step velocity increases were observed only in the first foot or so of rock movement. This observation indicates that the gaseous products of the explosion do additional work on the rock after it is crushed and cracked by the initial compressive-stress pulse and the reflected tensile-stress pulse. The observed initial fly-rock velocity is compared with the calculated fly-rock velocity for reflection spalling. A mechanism possibly causing the velocity increases is discussed. INTRODUCTION When a small concentrated charge of explosive is detonated at the bottom of a drill hole near a free surface, two modes of rock failure have been observed; both are associated with the stress pulse generated in the rock by the detonating explosive. The first mode of failure is the crushing and radial tensile cracking associated with the initial passage of the compressive-stress pulse as it propagates outward from the explosion. This type of rock failure is usually confined to the immediate vicinity of the charge hole. The second mode of failure is the tangential and radial tensile cracking associated with the tensile-stress pulse that is reflected from the free surface. This mode of failure is commonly called scabbing or spalling and has been shown to be a primary cause of rock failure in crater formation at one free surface. (3).4

Jan 1, 1961

By R. V. Lundquist

The specific conductance of solutions of sodium hydroxide and of sodium aluminate was directly proportional to the temperature. The specific conductance of sodium aluminate solutions with identical sodium ion concentration and at constant temperature decreased with increase in aluminum concentration. The aluminate ion population in solution was shown to consist of a mixture of monovalent and polyvalent ions. Aluminate ions did not influence the temperature dependence of pH in caustic solutions containing sodium aluminate. The density and viscosity of a solution was inversely proportional to the temperature and directly proportional to the concentrations of sodium and aluminate ions.

Jan 1, 1965

By I. D. Shah

Thermal decomposition of copper (II) sulfate (CUS04) and copper (II) oxy-sulfate (CuO?CUS04) are important steps in the overall oxidative roasting of covellite (CuS) and chalcocite (Cu2S). Nonisothermal thermogravimetric techniques were used to investigate the decomposition reactions in flowing Na and air. Thermal decomposition of CUS04 and CuO?CUS04 followed "linear" kinetics with an apparent activation energy of 55±2 and 66±3 kcal per mole decomposed, respectively. These apparent activation energies comply with those previously reported when isothermal kinetic techniques were used. The addition of oxygen decreased the rate of decomposition, while small amounts of iron which were admixed with CuO?CUS04 did not have a significant effect. Neither oxygen nor iron had any appreciable effect on the apparent activation energy of the decomposition reaction.

Jan 1, 1972

By M. M. Tilman

The Bureau of Mines investigated the precipitation strengthening of lead¬-base alloys containing 0.5 through 4 weight-percent combined Cd plus Sb. The Cd and Sb were alloyed in a 1-to-1 atomic ratio which maintained compositions along the quasi-binary section Pb-CdSb. Tensile properties, creep rates, and stress-rupture values were obtained on alloys in the aged condition. The highest tensile strength was observed in an alloy of Pb-3 CdSb, After aging for 6 months at 90°±3° F, this alloy had a mean tensile strength of 8,950 psi with 15-percent elongation. An aged alloy of Pb-1 CdSb exhibited a steady state creep rate of 1.2 X 10-3 percent per day at a stress of 500 psi and a temperature of 90°±3° F. Times to rupture at stresses up to 4,000 psi and at a temperature of 90°±3° F were obtained for some compositions.

Jan 1, 1970

Provide respiratory protection for escape in a toxic or oxygen-deficient atmosphere with a device small and light enough to be belt-worn. Approach Combine a 10-minute, belt-worn respirator with a stored, larger, long-duration (60-minute) attachment that can be plugged into the 10-minute unit without removing the mouthpiece. How It Works The 10-minute device will be carried by the miner at all times, and the 60-minute canister or attachment will be stored near the miner. In the event of a disaster, the 10-minute device would be donned immediately. The miner would then proceed to the stored 60-minute unit and plug it into the 10-minute unit. For the 10-minute unit, a breathing circuit was developed in which air is passed through the KO2 bed twice per respiration. The 60-minute canister differs from the 10-minute unit in that air is drawn only once through the chemical bed per respira-

Jan 1, 1981

By J. A. Organiscak

Enclosed cabs are a primary means of reducing the silica dust exposure of equipment operators at surface mines. The National Institute for Occupational Safety and Health (NIOSH) has investigated various factor effects on enclosed cab air filtration system performance. Factors experimen­tally investigated were intake filter efficiency, intake air leakage, intake filter loading (filter flow resistance), recirculation filter use and wind velocity effects on cab penetra­tion (inside to outside cab concentration ratio). Adding an intake pressurizer fan to the filtration system was also investigated. Results indicate that the intake filter efficiency and recirculation filter were the two most influential factors on cab penetration. Use of a recirculation filter significantly reduced cab penetration over the intake air filter by itself due to the multiplicable filtration of the cab interior air. Cab penetration was also affected to a lesser extent by intake filter loading and air leakage. Adding an intake pressurizer fan notably increased intake airflow and cab pressure while providing only minor changes to cab penetration.

Jan 1, 2008

Reduce the dust exposure to the operator of a longwall shearer with a novel foam spray system. Approach Discharge foam through the nozzles of a shearer drum so that foam and coal are better mixed. How It Works Bureau of Mines research showed that two very important principles for successful application of foam are: (1) moisture distribution and (2) degree of mixing. Foam can distribute a given quantity of moisture much more evenly over a large surface area. Successful Bureau tests of foam for dust control always involve a high degree of mixing between the foam and the material, Mixing, permits a greater distribution of foam throughout the mined product. The most suitable location of foam application would be at the point where the dust is generated, before the dust becomes airborne. Foam nozzles located in the cutter drum (pick face foaming or ejecting foam through scroll sprays) will suppress dust close to its source.

Jan 1, 1989

By Lloyd A. Morley, Alan M. Christman

Introduction A wealth of information exists which deals with electrical grounding, both from a general viewpoint and from a specifically mine-oriented approach. Many parameters must be investigated in order to thoroughly cover all of the variables which govern the performance of electrical grounding systems. The emphasis of this work on open-pit practices re- presents a new development in the field of grounding research, and an exhaustive review of the relevant historical documentation is especially desirable. Grounding System Purposes What purposes are served by a grounding system? The answer is four-fold and may be summarized as follows. First, it must limit potential gradients between conducting materials in a given area (56). When a phase conductor comes into contact with a machine frame, current flows through the equipment, which tends to become elevated above ground by an amount equal to the voltage on the conductor. If a man were to touch the machine while he was simultaneously connected to ground in some manner, his body would also tend to become elevated in potential, possibly to a lethal extent. Thus, the grounding system should provide a low- resistance path for the fault current to return to the source. The maxi- mum potential to which a man could be exposed when touching a machine frame is equal to the voltage drop along the ground conductors inside the power cable, as shown in Figure 1 (54). The ground conductors, therefore, (page # 96 is missing from the original document)

Jan 1, 1976