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By B. Yarar

Samples of coal from an adit in the Fording River District of British Columbia showed hydrophilic properties between depths of 0-24.5 m (0-80 ft) and was naturally hydrophobic at greater depths. Laboratory experiments indicated that weathered samples (i.e., those mined at 0-24.5 m) could be upgraded by froth flotation at pH32 following slimes removal. The i.e.p. of samples varied regularly between pH = 1.6-4.1, the weathered fractions being at the lower end of the pH scale. These values followed a pattern comparable with the flotation behavior of samples. A patchwise structure for coal surfaces determining the resultant disjoining pressure which in turn determines flotation-non-flotation relationships is postulated.

Jan 1, 1983

By James Boyd

It is obvious that mining has been influenced to a high degree by political and economic events, many of which are of such a nature that the mining industry has relatively little influence in shaping them. I cannot present too optimistic a picture for the immediate future, although I feel that from the long-range standpoint one need not be pessimistic about the future of the mining industry. The population of the United States is continuing to increase and with it has come an expanded consumption of metals on a per capita basis. With this expansion there has and will continue to come the demand for more goods and in- creased products from our mines and our fabricating plants. World War

Jan 5, 1950

By Cyril Stanley Smith

The following table, which is composed of data given in the author's first paper on the thermal conductivity of copper alloys1, contains tile results which have been obtained by previous workers on the thermal conductivity of the copper-tin, the copper-phosphorus and the copper-tin-phosphorus alloys (the phosphor bronzes). a Dr. Ing. Diss., Aachen, 1909. Quoted by Schenk: Ann. der Phys. (1910) 32, 261. b Beibl. Ann. der Phys. (1906) 29, 178. c Jnl. Inst. Metals (1928) 39, 375. d Jnl. Inst. Metals (192.5) 34, 43. e Ges. Abhand. Kennt. Kohle (1919) 4, 400. Experimental Methods Since the method of obtaining measurements of the thermal conductivity was identical with that described in the author's previous paper

Jan 1, 1931

By Lawrence F. Schubert

Instrumentation is not a stranger to the minerals processing industry. In fact, very few plants now exist that haven't to one extent or another adapted operations to instrumentation. But with the rapid growth of such controls has come the need for effective departments composed of men trained to maintain and repair the instruments; here is where many firms fall short. The importance of the role an instrument department should play is underscored by the omnipotent effects which instruments often exert over an operation. Reserve Mining Co. is an example: while instrumentation at this taconite plant represents approximately 2% of the process equipment cost, a breakdown of instruments may result in the ineffective use (or complete shut-down) of the other 98% of plant investment.

Jan 7, 1966

By R. A. Turpin

Bethlehem Steel's Research Department is developing a set of computer programs as mine-planning tools for Bethlehem's coal mines. Several of these computer programs have been completed and have been in routine use by Bethlehem Mines personnel since early 1975. The production scheduling and ventilation planning programs have been installed on an interactive time-sharing computer. The use of time sharing allows mines in remote locations to access these planning tools through standard phone lines and low-cost computer terminals. The capabilities of the interactive production scheduling and ventilation planning programs are briefly described. The advantages of implementing them using time sharing are discussed. A case study illustrates some of the benefits that planning based on the use of these programs has already provided.

Jan 1, 1977

By G. E. Karantzavelos

Anew flotation process to recover alunite from low-grade alunite ores is described. The process begins with run-of-mine ore, reduced to less than 5 mm (0.2 in.), being preconditioned with the reagents before grinding and alunite flotation. From the preconditioning step, ore particles, impregnated with reagents, form pellets that subsequently disintegrate into the pulp during grinding. The second step is basically a standard alunite flotation step. Pilot plant test results show that an alunite concentrate assaying at least 85% alunite and less than 5% silica can be produced. Laboratory and pilot plant results were in excellent agreement, indicating that the new process is a viable means of alunite beneficiation. Plant results, using the new process, were superior to results from conventional alunite flotation procedure.

Jan 1, 1986

By W. E. Newberry

The Aspen Mining District is situated at the eastern edge of the system of stratified rocks of western Colorado, where this edge meets the ridge of metamorphic granite which divides the State into two unequal parts. In following the valley of the Roaring Fork westward from the continental divide towards Aspen, one passes through a country of granite and gneiss, with no sedimentary rocks until the town is nearly reached. At this point the Cambrian quartzites first make their appearance, lying on the granites, with a dip of from 30' to 45 to the northwest. Beyond these quartzites and conformably upon them lie dolomites, limestones, shales, porphyries and sandstones, gradually flattening in general dip as one proceeds westward, but much disturbed by local foldings and faultings.

Jan 1, 1890

By A. Mitchell, M. Etienne

VARIOUS'-3 reports on the electroslag remelting process refer to the "thin skin of slag" existing around the slag pool and the solidifying ingot, but none considers the various mechanisms by which this layer forms and thus influences the surface quality of the ingot. A vertical section4,5 of the Cao-CaF2-Al2O3 diagram is shown in Fig. 1 between CaF2 and 6Al2.CaO3 From this, it is seen that a typical "70:30" CaF2:A1a3 slag will solidify to produce 6Al2O3.CaO primary phase in a eutectic matrix. The commercial slags contain sufficient CaO to produce* this composition by both the

Jan 1, 1969

By Philip Lindstrom

T he Radon mine is in the north end of the Big Indian mining district in San Juan County, Utah. Hecla Mining Co. operated the mine from early 1955 to early 1964 through an operating agreement with Federal Resources, Inc. Development consisted of a 3-compartment, 690-ft shaft, 4 main levels driven on the ore horizon and a haulage level below the ore. Evaluation of physical and economic factors showed that this flat-dipping ore occurrence could be mined by a low-cost coal mining method. The value of the deposit was high and unusual pre¬miums were possible by clean mining. Complete extraction without loss of ore pillars, minimum ore dilution and high production per man were obtained by longwall mining.

Jan 12, 1964

By M. Hayri Erten

In this research the possibility of pelletizing high grade fluorsoar fines or flotation concentrates with the use of calcined colemanite as binder is investigated, and the room temperature and elevated temperature strengths of these pellets are compared with those of pellets which are obtained by using bentonite as binder. Pellets of 10-12 mm. size and having 10% calcined colemanite showed a much higher room temperature strength than those containing 5% benonite, both being endurated at 1000°C for 15 minutes. However, when the same batch of pellets were tested at elevated temperatures of 250º to 500°C, bentonite gave better results. X-ray tests showed that in the pellets endurated at 1000°C for 15 minutes the original crystal structure of fluorite mineral is preserved.

Jan 1, 1977

By Milton C. Neul

As recently as the mid-1930's, steam and rail haulage were still the primary means of moving large quantities of rock. However, 2- to 5-ton standard on-highway trucks were beginning to be used in the mining industry's efforts to lower haulage costs. It was quickly obvious that rubber-tired equipment was more flexible, faster and more maneuverable. The trend towards haulage trucks had begun. Now while savings were being realized, the severe operating conditions encountered in open pit operations proved too much for the lightly constructed frames, gasoline engines and highly inflated tires. As a result, a few years later, the first 10 to 15-ton, two-axle heavy duty trucks were designed specifically to operate under off-highway conditions.

Jan 3, 1966

US 4,183,899 - Flow process for chlorinating ilmenite. A laminar flow of a mixture of ore, a carbonaceous reductant, and chlorine gas or other chlorinating agent is passed through a reaction zone maintained at a temperature of 1350 to 1950°C and a product stream Including titanium tetrachloride is withdrawn from the zone. The atomic ratio of carbon to oxygen in the feed mixture is greater than 1:1, and the molar ratio of chlorine to titanium solids In the product stream is between about 0 5.1 and 2:l. Titanium chlorides and metallic iron are recovered separately from the product stream. J.P. Bonsack, assigned to SCM Corp, Jan. 15, 1980 21 pp. (423-79). Filed. 3-10-78 (885,442).

Jan 1, 1982

By H. Nakazawa, I. Iwasaki

Galvanic contact, occurring between electrically conducting minerals in flotation pulps, may affect the nature of mineral surfaces and influence their floatabilities. Rest potential and galvanic current measurements were made on an electrode combination of pyrite and pyrrhotite under nitrogen, air and oxygen aeration conditions. The results were correlated with their oxygen-consuming characteris- tics and flotation behaviors. The galvanic contact improved the floatability of pyrrhotite, but adversely affected that of pyrite. Auger electron spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy indicated that the formation of hydroxide or oxide and sulfate species of iron on pyrrhotite decreased, whereas that on pyrite increased when these minerals were held in contact. An electro- chemical mechanism was proposed for the observed behaviors.

Jan 1, 1986

US 4,192,852-Precipitation of iron values as a jarosite from a sulfate solution obtained as a byproduct in the hydrometallurgical processing of zinc sulfide ore The solution is cooled, partially neutralized, and clarified. The clarified solution is heated to a temperature of 80 to 100°C in the presence of sodium, potassium, or ammonium ions to precipitate substantially all of the ferric iron as jarosite The precipitate is thickened, filtered, and washed The residual solution may be processed for zinc or other nonferrous metal values R V. Pammenter and C J Haigh, assigned to Electrolytic Zinc Co of Australasia Ltd. Mar. 11, 1980. 16 pp. (423-42) Filed: 5-8-78 (903,524). Priority- Australia, 5-9-77 (PD0030) (Drawings below.)

Jan 1, 1982

By H. M. Strong, R. A. Oriani

THE technological interest attaching to light, age-hardening alloys for structural uses has been pointed out to one of us.1 A potentially interesting alloy would be titanium-rich Ti-Mg alloy, provided that sufficient solid solubility exists. or could be induced at high pressure. and provided also that age hardening can be induced by proper temperature and/or pressure annealing. It was decided therefore to explore the feasibility of producing a Ti-Mg alloy in the high-pressure apparatus. Experimental. Three high-pressure runs have been carried out. In each case the geometry of the sample was that of a cylinder of titanium of commercial purity, into which a narrow hole had been drilled along the axis; this hole was filled with magnesium wire,

Jan 1, 1967

By Dale A. Augenstein, S. C. Sun

A primary concern in the solution of any solid waste disposal problem is the characterization of the material. In the past, available methodology for the determination of coal refuse characteristics has been severely limited by the inseparable combination of organic and inorganic matter of which the refuse is comprised. The recent development of an electronic, low temperature asher which removes the organic material without alteration of the inorganic constituents has opened new areas of coal and coal refuse research. This study deals with the development of methodology for the characterization of Pennsylvania anthracite refuse through utilization of the low temperature asher. Seven samples of anthracite refuse were examined for verification of the methodology developed and information concerning the characteristics of the refuse.

Jan 1, 1975

By Helen L. Cannon

BOTANICAL methods of prospecting for metalliferous ores are based on the premise that deposits at depth may be reflected chemically in surface vegetation. For the past several years, on behalf of the Atomic Energy Commission, the U. S. Geological Survey has investigated on the Colorado Plateau the application of botanical methods to uranium prospecting. Results suggest that orebodies may be found under a considerable cover of barren sandstone through the absorption of uranium and associated trace elements by plants growing at the ground surface. Plant physiologists have demonstrated that uranium is a necessary nutrient for plant growth and therefore is present in all plants.' The amount present is small but measurable. The absorption of uranium by plants growing over ore deposits forms

Jan 1, 1955

By S. Chander, D. W. Fuerstenau

Hallimond tube flotation, contact angle measurements, electrokinetics, and electrode potential measurements have been used to investigate the natural floatability of molybdenite. The effect of surface pretreatment and the role of hydrogen, hydroxyl, molybdate, and calcium ions on the flotation of molybdenite has been studied. The surface potential of molybdenite has been suggested to be controlled by HMoO[ ] and MoO4= surface species whose properties are strongly influenced by pH. Calcium ions, which appear to be specifically adsorbed, are able to reverse the zeta potential of molybdenite. The experimental results have been analyzed in terms of the Derjaguin model of wettability, namely in terms of van der Waals and electrical double layer interactions and hydration effects at interfaces.

Jan 1, 1973

SULFURIC ACID U.S. 4,070,260 - Sulfuric acid leaching of willemite, hemimorphite, or other zinc silicate ore. Ore is leached with at least a stoichiometric amount of a IN to 6N sulfuric acid solution at a temperature near its boiling point to form a gelatinous mass of hydrated silica and zinc sulfate, the water in the mass partially evaporated to crystallize all of the silica, the mass treated with hot water to dissolve substantially all of the zinc sulfate, the suspension filtered, and zinc values recovered from the filtrate by electrolysis. N. Dreulle, assigned to Compagnie Royale Asturienne des Mines. Jan. 24, 1978. 3 pp. (204-119). Filed: 2-10-76 (656,966) . Priority: France, 2-14-75 (75/04594) .

Jan 1, 1979

By D. A. Dahlstrom

(A. C. Richardson and Charles C. Boley, presiding) W. E. BROWN*—In the operation of the cyclone, what factors have you found that will affect its results as far as efficiency goes; for example, if you have coming through the cyclone a pulp of 20 gpm, that has, say, 25 or 30 pct solids, and then from operational characteristics this pulp changes to 35 pct solids but it is still maintaining the same ratio of flow. HOW does that affect the cyclone;) D. A. DAHLSTHOM (author's reply) —It has a definite effect, as you know from Mr. Sutherland's paper,l3 in that as you increase the solid concerltration of your inlet slurry, you will naturally have an according effect on the overflow concell-

Jan 1, 1950