Search Documents

By F. D. Dietiker

After determination of the requirements for a given application, proper selection of a belt conveyor is made from tables and formulas commonly used by conveyor designers. Belt conveyors, which are universally accepted as a means of transporting bulk materials, also perform the important functions of stockpiling and reclaiming.

Jan 1, 1978

By Clarence O. Babcock

A simple robust rock bolt load gage was tested in the laboratory to define its characteristic behavior and to obtain a measure of its performance. The gage uses three vibrating wire sensors crimped 120 (2.09 rad) apart into the outer surface of a hollow cylindrical steel, tube. The resonant frequencies of the wires change as the gage is loaded. This change is read with a Creare meter developed for the Bureau of Mines on a previous contract to read borehole stress gage results. A statistical analysis of data obtained defines the variables influencing results. A U.S. patent (3,914,992) assigned by the author to the Dept. of the Interior was granted Oct. 28, 1975.

Jan 1, 1978

By L. Bombardieri, H. F. Mills

Iron King mine, producing gold-silver-lead-zinc-ore, is 10 miles east of Prescott, Ariz. At present the 1806 level is being developed. The echelon pat tern of ore deposit continues at depth but is less pronounced, and the orebody is now more or less continuous over 2600 ft of strike length, with widths 5 ft to as high as 26 ft where overlapping of lenses occurs in one section of the mine. Better continuity of ore at depth has encouraged systematic mining and improved plant facilities to offset higher operating costs. With favorable persistence of ore at depth, the three-compartment No. 6 hoisting shaft appeared inadequate to handle increased tonnage from greater depths, and in 1952, a four-compartment steel and concrete shaft was started. This is now at a depth of 1906 ft, and shaft pockets and loading cartridges are being installed on the 1806 level. Ore from the new shaft, hoisted in 5 ½ -ton Jeto bottom dump skips, is dumped into a 500-ton shaft bin, from which it is fed to a 16x30-in. gyratory crusher and conveyed 415 ft through an undersurface concrete gallery to the secondary crusher and conveying system supplying the 900-ton mill. Lead, zinc, and pyrite concentrates are floated, and the flotation tailings are cyanided after desliming. Waste from the new shaft is dumped into a 250-ton surge bin, fed from this bin to a 24-in. conveyor, and discharged into the glory hole above the block cave. The new shaft is served by a double-drum 400-hp hoist used for ore and waste; the No. 6 shaft conveys men and material.

Jul 1, 1956

US 4,192,851-Recovery of elemental sulfur and the metal values from a complex sulfide ore containing two or more of the metals zinc, lead, copper, silver, gold and/or other metals. A mixture of ore and sulfuric acid and/or spent electrolyte is flowed at optimum temperature and pressure in a quiescent zone to dissolve selected metals and sulfur and coalesce the sulfur. The coalesced sulfur and unreacted sulfides are separated by flowing the leach slurry with an upward velocity component The separated materials are discharged and further processed by conventional methods as war- ranted. H.E. Hirsch, J F. Higginson, EG. Parker, and G M Swinkels, assigned to Sherritt Gordon Mines Ltd. Mar. 11, 1980. 6 pp. (423-28) Filed. 3-14-78 (886,368). Priority. United Kingdom, 3-15-77 (10800/77).

Jan 1, 1982

By Eugene P. Pfleider, Jared Scofield

During the past ten years, the trend on the Mesabi Range has been toward the establishment of integrated operations which mine, concentrate, and pelletize the large reserves of magnetic taconite. However, since the supply of open-pit ores of acceptable quality is by no means inexhaustible, it has been proposed that it be supplemented by developing the magnetic taconites that extend down dip past the economic limits for open-pit methods. In Phase I of a long range study, Pfleider and Yardley1 collected information on the general character of the Mesabi iron formation at depth and proposed that an underground lane-and-pillar mining system be considered to extract those high grade layers where they might exist over a considerably areal extent. An approximate cost estimate was included initially, with the thought of later developing a feasibility study as time permitted.

Jan 9, 1967

GENTLEMEN : It is my privilege to transmit herewith the reports for the calendar year 1932 of your Treasurer and the Chairmen of the following Standing Committees: Finance, Admissions, Membership, Papers and Publications, Library, and Mining and Metallurgy. To these reports you are referred for additional details of the year's activities. Finances.-Continuation of depressed conditions in the mining industry (in common with other industries) caused the income of the Institute to decline from $168,274 in 1931 to $138,331. However, economies were effected so as to reduce expenditures from $171,198 to $135,977. As a consequence the net result of the operations for the year was a-surplus of income amounting to $2,354 compared with a deficit of $2,924 in 1931. This gratifying result is accounted for in large measure by the foresight of the Finance Committee in anticipating a substantial decline in income and preparing the budget accordingly. Incidentally, the tentative budget for 1933 has been balanced at $125,000.

Jan 1, 1932

By T. M. Olson, B. G. Lewis

The adsorption of selenite on bentonite, kaolinite, and an iron--coated illite was studied to determine the importance of several soil variables on selenite removal from uranium mill tailings pond seepage. Adsorption capacities of the clays of selenite varied by orders of magnitude and decreased in the following order: illite > kaolinite > bentonite. Maximum adsorption of selenite on the clays was observed between pH 2.5 and the clay's zero-point-of-charge. Substantially less selenite was adsorbed on these clays in actual mill tailings solutions than in model systems. Virtually all selenite was removed from the tailings at pH 7. The principal removal mechanism at this pH is suggested to be the adsorption of selenite on freshly precipitated metal hydroxides. It is concluded that selenite can be removed from tailings seepage in soil or in clay liners in the presence of kaolinitic clays and iron oxides. Selenite would also tend to be removed from tailings seepage in calcareous strata.

Jan 1, 1984

By George C. Reynolds

INTRODUCTION The overall importance of the minerals industry during the next 20 years was highlighted In "The Global 200 Report to the President" (Barney, 1982) in the following terms: "The industrial and agricultural processes that are taken for granted today would be severely disrupted of any one of dozens of critical minerals ceased to be available in dependable, reasonably priced supply. Supply in turn has become highly energy intensive and international In scope ...... because resources are not uniformly distributed geographically, political considerations (also) become an Important determinant of price and trade patterns." In attempting to determine Australia’s contribution of bauxite raw materials to the world of the future, this paper necessarily also concerns itself with the alumina and aluminium industry to which it supplles the raw material. It is an industry which is energy intensive, International in scope and heavily influenced by political considerations. The aluminium industry has shown a remarkably rapid growth during the past 20 years (Fig. 1).

Jan 1, 1982

By Clemens Catesby Jones

The substance of this paper, now amended and altered in form for its present use, was the basis of a private report prepared under professional engagement.* A private report is necessarily objective, and deprived of the scope and technicality of a scieintific treatise—which accounts for the prevalence of drawings and succinct mathematical statements rather than full descriptive details in a paper reproduced from data, of which all the original working-notes have been destroyed. In a practical sense the Hudson river valley clay-deposits owe their present existence to the protection afforded by the rock-formations on which they are supported, and, instead of being uniform in depth or continuity, are subject to the irregularities of the rugged masses which preceded and are now concealed by them. The only available information concerning these deposits contained in previous public reports or maps furnished at best a mere photograph of the surface, and as now apparent this was misleading or unreliable. It was the object of this investigation to determine in a practical manner the location, form and extent of all the clay-deposits at present existing in the lower Hudson river valley, and to ascertain with a

Jan 1, 1900

THE annual winter meeting of the A.I.M.E., which is to open in New York on Feb. 14, will be charac-terized by a number of novel features. The most important is that the technical sessions will be dis-tributed over four days instead of three as heretofore. This makes it possible to reduce the number of conflicts between sessions and also will enable each member to attend a larger number. At the same time the ses-sions are so arranged by groups that those interested only in one or more that are related can, if necessary, cover all in that group in three days as heretofore. The general excursion to which the fourth day has, for some years, been devoted has been regretfully given up, mainly because of the uncertainties of the weather in New York in February. In its place a series of group excursions are being offered at various times during the meeting, arranged, so far as possible, so as not to con-flict with any technical session likely to be of interest to those taking part in a particular excursion. Among the places to be shown the visitors are: the construction work on the Eighth Avenue subway, a real mining job; the Vehicular Tunnel, the world's greatest ventilating project; the manufacture of 42-in. conveying belts; one of the largest and most modern steam plants; a coal terminal; manufacture of mining equipment; a cable-making plant; an oil terminal and refinery. Other en-tertainment features include a smoker Monday evening with a real chance to get together and talk; an informal dance and entertainment given by the Woman's Auxiliary on Tuesday evening; the dinner-dance at the Waldorf Wednesday evening, with no long speeches; a general session Thursday evening when the Petroleum Division will present a series of important reviews of the year. An extensive program has been arranged for enter-taining the ladies, and members are urged to bring their wives. There will be dinners, teas, theater parties, shopping and sight-seeing excursions as well as the dances. The usual general luncheons for members, guests and ladies will be served each day at headquar-ters, and various committees and groups will hold lunch-eons, dinners, and round table conferences as indicated in the schedule on the page opposite. The Mining and Metallurgical Society of America and the American Society of Steel Treaters are participat-ing in this meeting and their members will be welcome as guests at any session or function. A joint conference of the Mining and Metallurgical Society and the A.I.M.E. has been arranged for Tuesday afternoon, under the chairmanship of Clinton H. Crane, at which the whole matter of the mineral reserves of this country is to be up for discussion.

Jan 2, 1927

By J. J. Arps, T. G. Roberts

Since the introduction of the relative permeability concept in the middle thirties1,2 various investigators have shown3,10,11,12,15 how the basic equations for the flow of oil and gas through porous media can he utilized to compute the recovery from depletion type or solution gas drive type reservoirs under certain conditions, when the necessary physical data pertaining to the reservoir rock and its reservoir fluids are known. In the study by Muskat and Taylor" in 1945, the effects of viscosity, gas solubility, shrinkage, and the permeability-saturation characteristics of the producing formation on the production histories and the recovery of gas drive reservoirs were analyzed. Each parameter was varied a limited number of times, while keeping the others constant. The work was not carried to the point where the data could be used directly to estimate the primary recovery in those cases where certain rock and fluid characteristics were known or could be assumed. Since the publication of this classic study, the work by Beal in 194616 and Standing in 1952'" has established general correlations of oil viscosity and shrinkage with gas solubility and oil gravity. In addition. a considerable number of relative permeability relationships for different types of reservoir rocks has been published2,5,13,17,19,20. Also, the burden of the numerical work required in the solutions of the differential equation has. during the last few years, been greatly reduced with the availability of modern electronic computing facilities. The purpose of this paper is therefore to present the results of a large number of such recovery computations covering the normal range of variation of the main parameters such as the type of rock, the API gravity of the oil, and the amount of gas in solution. As is to be expected, the ultimate recovery is found to increase with the oil gravity. except for the higher solution gas-oil ratios. Within the normal range of solubilities, the ultimate recovery generally appears to decrease with the amount of gas in solution for the higher oil gravities, and to show a slight increase for the lower oil gravities. Intermediate oil gravities seem to fall between the two trends. The type of reservoir rock, as identified by its relative permeability relationship, appears to have a very pronounced effect on the ultimate recovery. In general, sands and sandstones show higher recoveries than limestones and dolomites, although certain intergranular limestones seem to show a higher theoretical recovery than unconsolidated sand. The recovery from sands and sandstones generally decreases with increasing cementation and consolidation, while the recoveries from limestones and dolomites are highest for the intergranular type and lowest for the fracture type porosity.

Jan 1, 1956

By Arthur G. Levy, Henry M. How

The purpose of the investigation on which this paper is based is to determine whether the structural change which occurs in the slow cooling of steel below the transformation range has an important effect on its engineering properties. We recognize two distinct things which occur in steel when it is brought from above to below the transformation range, first, the transformation proper, that is, the breaking up of the austenite or solid solution of the cementite in the remainder of the iron, and the liberation of its components as undissolved cementite and as ferrite or alpha iron; and second, a structural change consisting in the gradual coalescence of the ferrite and cementite respectively into larger and larger separate masses. Let us distinguish these from each other by speaking of them as " the transformation " and " the structural change " respectively. If the cooling is at all rapid the unevenness of contraction induces severe stress; so that in a sense a slow cooling has a third influence, the prevention of such stress. This transformation from austenite to ferrite plus cementite can complete itself only below the transformation range; and, because this structural change is a change in the structural arrangement of the products of that transformation, it too can complete itself only at temperatures below that range, say below 725°; and of these temperatures it is only those between 600° and 725° that give the metal sufficient mobility to permit this structural rearrangement to progress with ally rapidity. The transformation is now known to be rapid, but the structural change is relatively slow. The transformation, the liberation of the dissolved cementite from the state of solution in the austenite to a free state, leaves the steel structurally in the

Jan 1, 1913

By W. S. Landis

IN brief, this is the story of an attempt to Americanize a process originally developed in Europe. The story will be recited in two sections, the first dealing with the process as developed by the European engineers; the second containing the improvements and modifications of American origin, together with some details of the operating results of the unit as finally assembled. Developments in other directions in this same field have not, up to the present, pointed out an economic future for the process, therefore our record here is largely a report of development progress. Whether some particularly favorable location will be found at some future time for a commercial installation cannot as yet be fore-told. The project is now at a standstill. The peculiar tools of the electrometallurgist should be of great interest to the zinc smelter. The low thermal efficiency of the zinc retort, its comparatively small-scale unit and its intermittent cycle as it stood in 1925, should make this art a particularly fertile field for the electric fur-nace. Yet in spite of years of work recorded in volumes of literature, and an expenditure of large sums of money, there is not a single electrothermic zinc smelter operating anywhere in the world. In this industry the electric furnace plays only a secondary part today.

Jan 1, 1936

By H. T. Mulryan

For the producer of industrial rocks and minerals, marketing is often the only means of survival. His material must be sold. There is little of the impersonal force of the market regulating supply and demand. No commodity exchanges facilitate his efforts to dispose of the material he produces, and the success or failure of his business depends primarily on prompt and correct response to market needs and requirements. This response is particularly vital where materials of low unit value must be shipped to distant consumers owing to a relative rarity of suitable deposits. The advantage of positive response to change can best be illustrated by hypothetical cases showing how problems can be turned into opportunity through marketing ingenuity. Three such cases dealing with materials of unit values in the range of $5 to $100 per ton are outlined below.

Jan 7, 1969

By Junichi Sato, Takash Suzuki, Tatsuo Imamura, Mamoru Hojo

INTRODUCTION Hitachi Refinery of Nippon Mining Co., Ltd. was constructed in 1911. The refinery began early to recover by-product metals and to manufacture copper products. Today, the refinery recovers gold, silver, selenium, platinum and palladium as by-products of the copper refining process and manufactures copper powder, copper foil, wire bars and chemicals for plating. In 1969, the capacity of the Hitachi Refinery reached 6,000 tons/month. (T/M). Because, at that time, the forecast was for the demand for copper in Japan to increase, planning for the expansion of the Hitachi and Saganoseki refineries was begun. A new 10,000 T/M capacity tank house, a new electrolyte purification plant and a enlarged anode slime treatment plant were planned for the Hitachi Refinery. Construction at the Hitachi Refinery began in December, 1970, and was completed in April, 1974. The development of new machines and processes has resulted in an efficient refinery with a production capacity of 16,000 TIM. This paper is a report on the new anode slime treatment plant at the Hitachi Refinery, and especially on the copper removal process in that plant, the Ferric Leaching Process.

Jan 1, 1976

By L. I. Hewes, Joseph W. Roe

A graphic solution of Kutter's formula for the flow of water has been worked out by Dr. L. I. Hewes in connection with his course in Graphic Computations, given in the Sheffield Scientific School, Yale University, which may be of interest to those who deal with canals, flumes and streams. 1.811 0.002811 , 41.66+ -n+-S- I Kutter's formula, V= - n 0 .00281 78- 1+(41.66 + 0.00281)7B781 is probably the most accurate of those proposed determining the flow of water. But it is extremely cumbersome, and if many calculations are to be made their solution becomes drudgery. The purpose of this chart, Fig. 1, is to furnish a rapid solution, sufficiently accurate to be well within the limits of the observed data. The chart consists essentially of three parallel scales, one for the mean velocity, V, one for the hydraulic radius, R, and one for the slope; a diagonal line, not graduated ; and a set of curves for the various values of n, the factor which involves the na-

Jan 1, 1910

By William Campbell

The structure of iron and steel, though the object of so much study and research for the past 25 years, is by no means thoroughly understood. In the first place, we have three or more distinct iron-carbon thermal diagrams, each with its own supporters, and each representing a theory of the structure and constitution of cast-iron. In the second place, by reason of the fact that austenite, the solid solution of carbon in iron, decomposes in the solid state into ferrite, or pure iron, and cementite (Fe3C), and that quenching from above this transition-range, no matter how rapid, cannot entirely prevent the change and thus preserve the austenite by itself at ordinary temperatures, it happens that under the microscope we find, in addition to the ferrite, Fe3C, and austenite, which the thermal diagram of steel requires, a series of transition-products with distinctive structures, to which have been given the names martensite, troostite, sorbite, etc. Now these transition-products, in addition to the solid solution, austenite, have been the source of much controversy, at times very bitter. One side would insist that, say, troostite was an entity, which the other side would deny, pointing out that it must be a transition-mixture, with a particular structure. That austenite was a solid solution of carbon in iron has been denied by one school; we have been told that Fe24C dissolved both Fe3C and Fe, and thus gave rise to a whole series of quenching-pro-ducts—all this in spite of the fact that no matter how the thermal diagrams differ in regard to cast-iron, they all agree in regard to the solid solution, austenite, for Fe24C finds no place on the diagram. Thus it happens that while the authorities fight both in regard to the iron carbon diagram and the structures met with in hard-

Jan 1, 1913

By L. C. De Jong, J. F. Shirley, M. L. Campbell

The Toquepala concentrator of the Southern Peru Copper Corp., located approximately 720 miles southeast of Lima near the Chilean border, processes 36,500 tons of ore daily containing between 0.50% and 3.00% copper. The molybdenite content in the ore also varies greatly, ranging from essentially nothing to as high as 0.15%. The 1966 yearly averages were approximately 1.20% copper and 0.03 % molybdenite. The three basic problems that plague the opera- tion of any molybdenite recovery plant are all present at Toquepala in large measures. Both the quantity of plant feed and the quantity of molybdenite contained in the plant feed are continuously changing. Even more detrimental to an efficient operation is the fact that the copper mineralization in the feed frequently changes once in every 24 hours and occasionally once a shift. From the point of view of the molybdenite plant metallurgist, there are four distinctive chalcopyrite concentrates and, at least, an equal number of chalcocite concentrates treated in the molybdenite recovery circuit. The various types of concentrates are distinguished mainly by their mineral content and how effectively the copper minerals are depressed by the different reagents used in the circuit.

Jan 9, 1967

By Robert E. Allen

The organized curtailment of California oil production is not yet one year old but during its first year it has accomplished so much that it is now firmly established as an agency of economic efficiency. The principle of cooperative curtailment has been adopted by other states and it is safe to say that the principle will continue as long as the demand for petroleum is notably less than the potential production. It' is interesting to note that this same principle of regulating supply to meet demand is now being urged for other industries, such as agriculture and mining. Since Oct. 31, 1929, when curtailment was instituted by the oil producers of Santa Fe Springs and Long Beach in an effort to avert the disaster of ruinously low prices which confronted them, there has been a constant and increasingly effective curtailment program in California. Prior to that time a notable effort toward the restriction of oil production was made under the direction of F. C. Van Deinse during the early summer months of 1929. A considerable reduction of oil output was recorded as the result of this effort, but because of incomplete cooperation and the discovery of still deeper zones at Santa Fe Springs the effort was abandoned; flush field production became unrestrained and prices soon fell to low levels. This initial curtailment movement was educational and experimental. It showed all operators a way out of their overproduction difficulties and developed the principles followed in later curtailment efforts. Thus it was that only a few days after their oil had been reduced to 60 c. per barrel, the operators of Santa Fe Springs got together and agreed to restrict their current production of more than 270,000 bbl. daily to not more than 150,000 bbl. daily. The operators at Long Beach followed the same course a few clays later and agreed to limit their production to not more than 110,000 bbl. daily. The Santa Fe Springs operators chose H. P. Grimm as umpire and director of their proration program. Neal H. Anderson was chosen umpire for Long Beach. Since that time, as the need for curtailment has increased, practically every field of the state has come under the curtailment of these two umpires. Curtailment of the Elwood and

Jan 1, 1931

By Wm Price

THE object of this paper is to present a survey of some of the physical properties of sheet nickel silver when subjected to cold rolling and when annealed at temperatures extending from 350° C. throughout the commercial annealing range. A number of alloys were taken from stock and analyzed. Four of these, representing low nickel and high nickel both with and without lead, were chosen for the tests. The analyses were as follows: ALLOY COPPER, LEAD, IRON, NICKEL, MANGANESE, ZINC, PER CENT. PER CENT. PER CENT. PER CENT. PER CENT. PER CENT A 64.68 Trace 0.194 - 6.73 0.06 remainder B 65.82 1.27 0.227 6.17 0.06 remainder C 65.44 Trace 0.345 17.83 0.08 remainder D 65.60 1.08 0.238 17.77 0.06 remainder These alloys were rolled in accordance with regular mill practice to approximately No. 6 B. & S. gage. The bars (which were then coiled) were annealed together in a mill muffle and afterwards pickled in a 10 per cent. sulfuric-acid solution and cold rolled in stages of approximately .one number (B. & S.) at a time to No. 18 B. & S. gage. After each stage, suitable samples were set aside for physical tests. Additional samples were chosen for tests after the bars were rolled to Nos. 8, 10, 12, and 14 gage. These samples were annealed together in the mill muffle and, after pickling, were finished on 0.050-in. gage, yielding a series of specimens 2, 4, 6, and 8 numbers hard for the subsequent annealing tests. Tensile test pieces 9 by 1 in. (22.9 by 2.5 cm.) were cut from both lots and the central portion was milled to give a test section 2 ½ in. long by ;Z in. wide. A distance of 2 in. was marked off on the edge of each specimen with light punch marks. In the case of the annealed alloys, Erichsen test pieces 4 by 2 1/2 in. were also taken.

Jan 10, 1920