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By H. Shafick Hanna, Carl Rampacek

Wastes generated by the mining, mineral processing and metallurgical industries now total about 1.8 billion tons annually. The wastes include gases, dusts, solutions and a variety of massive solid mineral materials such as tailings and slags all of which now must be disposed of with a minimum of environmental degradation and at an acceptable cost. Some of the metal and mineralconstituents have potential economic value and their recovery can augment our primary mineral and metal resource supply base. The resource potential of wastes generated by the iron and steel, aluminum, clay, phosphate, copper, coal mining and processing, nonmetallic, and selected secondary metals industries is identified. Information on current efforts being made to recover these resources and the technology now employed or under consideration are presented.

Jan 1, 1980

By Chandler Morse

RENEWABLE VS. NONRENEWABLE NATURAL RESOURCES Nonrenewable resources, such as minerals, are the inevitable center of attention in discussions of depletion and exhaustion. Nevertheless, it may well be proper to regard some nonrenewable resources as not subject to exhaustion, and renewable resources may sometimes be treated as if they were finite stocks. Thus, the availability of nonrenewable resources is not and probably never will be known completely Chap. 2.5A, and therefore is not subject to firm predictions concerning exhaustibility. Moreover, because exploration and discovery are more or less continuous processes it is often appropriate to regard mineral supplies as flows, and to treat the estimated reserves as working capital, an inventory, continually depleted by use and augmented by discoveries.23 The aggregate economically exploitable stocks of a given mineral are seldom estimated (or estimatable) with precision, as Chap. 2.5A shows, and even when they are, forecasts concerning years of remaining life can be and often are falsified by changes in one or more of the multidimensional conditions of supply and demand; or the productive services formerly derived from an exhausted stock may continue to provided without material impairment by one or more substitutes b Conversely, the renewable resources are all subject to depletion when the rate of use exceeds the natural or induced rate of replenishment, and cases of exhaustion or near exhaustion, as through soil erosion, overcuttmg of forest lands, and overfishing, are rather common c Where exhaustion is a clear possibility the resource may either be exploited on a consciously adopted "sustainable yield" basis or be treated as an exhausting asset." In some cases, conscious treatment

Jan 1, 1976

Jan 1, 1951

NEW MEMBERS The following list comprises the names of those persons who became members during the period of June 10, 1918, to July 10, 1918. ALLPORT, JAMES H., Cons. Engr Barnesboro, Pa. ANDERSON, G. E., Engr., Exploration Dept., American Smelt. & Refin. Co.,Tucson, Ariz. BAKER, HARRY A., Capt., Co. M, 53d Pioneer Infantry, Camp Wadsworth, Spartanburg, S. C. BEALL, ROBERT STEPHENS, Supt., Empire Zinc Co. (of Colorado), Canon City, Colo. BLAYLOCK, SELWYN GWILLYM, Mina & Met. Engr., Asst. Gen'l Mgr., Cons. Min. & Smelt. Co. of Canada, Ltd., Trail, B. C., Canada. BOTTERILL, THOMAS CLARK, Min. Engr., Belmont Surf Inlet Mines, Ltd., Surf Inlet, B. C., Canada. BOWMAN, MAURICE Asst. Supt., New Idria Quicksilver Min. Co., Idria, San Benito Co., Cal. BROOKS, EARL W Chief En r. Inland Collieries Co. Harmarville Pa. BROWN, DEWITT W Chief Chem., Prime Western Spelter Co., Iola, Kansas BUISSON, ARTHUR Min. Engr., Dept. of Mines, Sussex St., Ottawa, Canada. BUNYAN, F. W Chem., Southern Pacific Railway Co., Sacramento, Cal. BURNETT, ARCHIBALD Supt., Swansea Lease Inc., Swansea, Ariz. BURTON, GEORGE E., Resident Geol., Empire Gas & Fuel Co., Varsity Shop Bldg., Norman, Okla.

Jan 8, 1918

At a special inaugural ceremony in Blue Hill, Maine on August 3rd, Governor John H. Reed detonated the first blast to signify the beginning of development work on a new copper-zinc mining venture that seems destined to focus increased interest in the mineral potential of that State. The property which is the first new base metal mine to be discovered in the northern Appalachians in 30 years, is owned by Black Hawk Mining Co., a subsidiary of Denison Mines Ltd. of Toronto. When it goes on-stream in 1966, it will join Ducktown, Tenn., as the only active copper producing region, east of the Mississippi River. According to official reports submitted by the Company to Robert G. Doyle, Maine's State Geologist, Black Hawk has found ore reserves totalling 4.5 million tons. Assays show 2.8 million tons of 2.0'; copper and 0.4 oz. of silver per ton; 1.2 million tons of 16.75% zinc and 0.58% copper; and 0.5 million tons of 6.75% lead with 4.25 oz. of silver per toil and some zinc.

Jan 9, 1964

By John Griffen

THEORY HYDRAULIC classification as explained by Rittinger and others was largely restricted to conditions wherein the free-falling velocities of the particles were conceived as governing the separations effected (see chapter 9). The laws governing classification under free-falling conditions have been summarized by Chapman and Mott as fo1lows:l Nomenclature r represents, in a particle of irregular shape, the round-hole screen through which the particle would pass, or some other linear dimension of the particle equivalent to d, the diameter of a sphere. s, the specific gravity of the particle. 1, the specific gravity of the water used as a medium. K, a constant. W, the velocity of the water. In an Upward Current of water 1. A particle will move upward if [V > K dr(s - 1)] and, by suit- ably regulating the speed of the water current, the larger and heavier particles may be made to fall downward against the current, leaving the smaller, lighter particles in suspension in the current. 2. Particles such that [- = -] cannot be separated in an upward- current classifier with any one velocity of current. Coal particles having a specific gravity of 1.35 cannot be separated from refuse particles of [2.5 - 1 2.5 sp. gr.] unless the ratio of diameters is less than [ 4.3 to 1, 1.35 – 1] and the raw coal must be screened to size limits within this ratio if they are to be separated. Cone-shaped vessels or vessels of other shapes that allow the use of different velocities of current at different points in the flow are used to modify this limitation.

Jan 1, 1943

By E. T. Hunter

Surrounded by the 13,000-ft high peaks of the San Juan Mountains in southwestern Colo., the town of Silverton is the site of the extensive development operations initiated 20 months ago by Standard Metals Corp. Appropriately termed the Silverton Project, Standard's operation has now passed the half-way point in its program to reopen two mines that were once sizeable producers of copper, lead, and zinc ores.

Jan 1, 1961

By Eli T. Conner

My connection, under a commission from the Councils and Board of School Control of the city of Scranton, Pa., with a recent investigation of mine-caves and the resultant damages to surface-improvements, has led to the preparation, at the invitation of our Secretary, of the present paper. It is notorious that there are, in the anthracite-fields, frequent subsidences of the surface, due to the removal of the coal beneath. No particular attention is paid to such occurrences, unless they happen to injure surface-improvements. Many caves have happened in Scranton and its viciuity, which hare excited but little remark, since they have generally caused no serious damage. In August, 1909, a cave occurred in the Hyde Park section of the city, generally known as the West Side, which nearly destroyed school-house No. 16 and considerable adjacent property. Fortunately, there were no pupils in the building at the time; but the thought of the possible result, had the usual number of pupils and teachers been present, aroused the public to the gravity of the situation; and the School Board employed engineers to investigate the case. Two reports were made by separate sets of engineers, which differed in some particulars. These differences were pointed out in the public press and magnified, and the consequent agitation of the subject was taken up and greatly exaggerated by some of the metropolitan newspapers, giving to uninformed people the very erroneous impression that the whole city of Scranton was in danger of sinking into the bowels of the earth. All this tended to affect the credit of the city and to depress real-estate values. The matter was considered at a joint meeting of the Board of Trade, the Councils, and the School Board. The Hon. J. Ben. Dimmick, a former Mayor, suggested that it

Jan 1, 1912

By Y. L. Yao

The solubility limit of oxygeu in a titanionn at 850°C has been determined by magnetic measurements as 12.5 + 0.5 pct (29.0—30,9 at. pct). Also in the susceptibility-co~centmtion curve, there is n distinct but not sharp maximum at 19.0 * 0.5 z~t pet (40.5--42.1 at. pct), which indicates the presence of the 6 phase. The magnetic susceptibilities of the alloys of the titanium-oxygen system were determined byEhrlich in 1939.' is alloys were prepared by sintiring mixtures of titanium and its oxide at high temperatures. On the titanium-rich side, despite the fact that the alloy compositions he measured crossed two phase boundaries, the limited results obtained

Jan 1, 1960

By Ralph Hultgren

FEW phase diagrams of alloys composed of two transition metals have been adequately studied, probably because of the high melting points involved. Transition metals are the elements that have inner shells incompletely filled with electrons. They comprise groups IIIa to VIIIa of the periodic table, including more than half of all metals. We have chosen to study two systems whose comparatively low melting points allowed the alloys to be melted in a molybdenum resistance furnace. The nickel-palladium system proved to consist of a simple series of solid solutions, but iron-palladium manifested several remarkable features. The main characteristics of the latter diagram were decisively established, but lack of time prevented precise determination of phase boundaries. The gamma to alpha transformation in this system is unusual and warrants further study. Grigorjew1 determined the liquidus and solidus of the iron-palladium system by thermal methods. He found a minimum melting point, but no eutectic. He also found that palladium lowered the gamma to alpha and raised the gamma to delta transformation temperatures of iron, with a complete series of solid solutions existing between gamma iron and palladium. His measurements also indicated a compound or super-lattice near the composition FePd3. Jellinghaus2 found that annealing at 500° C. greatly increased the magnetic coercive force of an alloy of composition FePd. X-ray dif-fraction photographs showed that a tetragonal ordered phase had formed during the anneal.

Jan 1, 1939

By Robert D. Pehlke, Robert G. Blossey

The solubility of nitrogen in liquid iron alloys containing chromium and nickel has been measured in the temperature range 1550° to 1700°C at nitrogen pressures to 1 ah. The solubility surface has been determined for the iron corner of the liquid metallic ternary to 21 pct Cr and 11 pct Ni. The nitrogen solubility increases markedly with increasing chromium concentration. The effect of nickel and the bilinear effect of chromium and nickel are less pronounced. The solubility data are presented, and interaction coefficients are determined from them. THE solubility of nitrogen has been determined in liquid Fe-Cr-Ni binary and ternary alloys. The work in this laboratory has been directed toward a relatively limited composition range, that is to 20 pct Cr and 10 pct Ni. Humbert and Elliott1 studied the entire ternary; but their investigation was, understandably, limited in this region. The region considered here is of the greatest commercial interest. Knowledge of the solubility in these alloys is important for accurate control of the nitrogen levels in various stainless alloys. Also, the solution behavior is of theoretical interest because of its deviations from ideal dilute solution rules at moderate chromium levels. The nitrogen solubility in the iron binaries has been reviewed extensively by Pehlke and Elliott,2 particularly with respect to the dilute solution interaction parameters. More recently, there has been some interest in accurate descriptions of solute interactions in non-dilute solutions. Most of the investigators have adopted a power series fit to accommodate any non-linearity of the data. The Taylor series expansion is adopted here, using Scimar's notation3 for the interaction coefficients. An alternate method, instead of requiring higher-order expansions, is to restrict the range of the composition variables. A planar solubility surface may be fitted to the data and its range of validity determined. If the axes of this region are displaced from the usual origin—the solvent pure iron—a change in standard state is required for the solution reaction. The standard state for nitrogen in iron is commonly taken as the hypothetical 1 wt pct solution of nitrogen in pure iron. However, for an alloy of appreciable solute concentration, e.g., 13 pct Cr or 18 pct Cr-8 pct Ni, it would be convenient to use that base composition as the solvent and redefine the solution reaction in terms of that particular solvent. A brief derivation follows, defining the free energy of solution in an alloy solvent. Following the treatment by Darken and Gurry,4 for a nitrogen pressure of 1 atm: N (pure component) = N (1 wt pct in solvent) [l] AG=RT ln100/ wt pct N in solvent Taking this reaction for an alloy solvent less the same reaction for a pure iron solvent the relation between nitrogen in pure iron and an alloy is: N (1 wt pct in Fe) = N (1 wt pct in alloy) [2] AG = RT[ln(wt pct N in Fe) - ln(wt pct N in alloy)] Adding ½ N2(g) to each side and subtracting N (1 wt pct in Fe) = ½N2(g), the total free energy for solution of nitrogen in an alloy, referred to nitrogen at infinite dilution, is given by: ½N2 (g) = N (wt pct in alloy) L3] AG°3 = -RT ln(wt pct N in alloy )PN =1 atm Interaction parameters have their usual meaning when ?G°/RT is differentiated with respect to the proper composition coordinate. If desired, the dilute alloy treatment may be utilized with the new reference composition as the solvent. This has. indeed, been done by Small and pehlke5 in their analysis of nitrogen solution in liquid 18-8 alloys. The Sieverts' technique was used for this investigation on an apparatus previously described.6 The materials used in this program were: Ferrovac-E iron, 99.95 pct, Crucible Steel Co.: chromium, 99.95 pct, Union Carbide Metals Co.; nickel, 99.9 pct, International Nickel Co. Recrystallized alumina crucibles were used with no evidence of crucible-melt reaction. RESULTS The locations of the ternary compositions investigated are shown in Fig. 1. The data of Turnock7 and small8 have been alluded to in other papers.5'6 There were no departures from Sieverts' law observed for

Jan 1, 1969

IN discussing the art of the goldsmith, it is apparent that it is an art requiring skill. He who wishes to be acclaimed a good master therein must be a good universal master in several arts, for the different kinds of work that come to his hands to be done are infinite. Those who work in gold and silver must outdistance all other craftsmen in learning and achievement to the same degree that their materials outdistance other metals in nobility. Therefore, it is necessary first of all to be a good designer, because design is the key that opens the doors not only to the goldsmith's craft but to all others. Then it is necessary that he understand melting and that he know well how to work with a hammer and how to use flat gravers and burins in engraving, as well as files and chisels. He must also possess certain secrets that are needful to the art, which in truth are parts of alchemy, such as softening gold when it is brittle and raw, coloring it when it has little color, soldering, enameling, working in niello, blanching, gilding, and an infinite number of things which must all be known in detail. But above all he who wishes to do this art well must be very patient in working, must know how to mould and how to proceed with the melt and with the file, hammer, chisel, or other implements for bringing his gold or silver work to the final state which he plans. He must also have good judgment in gems and know well how to recognize every [134v] good or defective quality they possess, and to distinguish the false gem from the true, either when set or when unmounted, as there is need; also how to value them both in buying or selling and in satisfying others who seek his appraisal. He should also be experienced not only in the technique of melting but also in the methods of assaying, parting, refining, cementing, and the like, and still many others. But if I wished to tell you of every part

Jan 1, 1942

By W. C. Ellis

NONFERROUS alloys upon which desirable properties can be conferred by heat treatment are becoming of increasing industrial importance. The alloys of copper with a constituent which has a solubility varying with temperature are materials of this character. Some of the constituents which are effective in producing a change in the mechanical properties of these alloys upon heat treatment are, according to Corson,1 nickel and silicon, iron and silicon, cobalt and silicon, and chromium and silicon. In addition to these elements, Gregg2 states that the combination of beryllium and silicon is effective in producing age-hardening characteristics in copper. The effect of these elements, however, as dispersion-hardening constituents in the copper alpha solid solutions does not seem to have been studied in any considerable detail. This paper deals with the heat treatment and properties of three alpha brasses containing 3 per cent. of nickel plus silicon in the proportion necessary to form the compound nickel silicide, Ni2Si. Some information of a preliminary nature in regard to the hardening by heat treatment of phosphor bronze containing the same percentages of nickel and silicon is included. The method of hardening the alloys, which is effective in increasing the tensile strength and proportional limit, is similar to that used in, the case of duralumin type aluminum alloys. It consists of a quench from a temperature at which the hardening constituent is in solid solution, followed by an aging at a lower temperature to precipitate the dissolved constituent in a dispersed condition. This results in an increased resistance of the alloy to deformation with an attendant improvement in the tensile properties.

Jan 1, 1929

By A. S. Keh, H. A. Wriedt

The Precipitation of nitrides in quenched Fe-N alloys, aged between 25° and 200°C, was studied by transmission electron microscopy. Different dislocation substructures were introduced into the materials by recrystallization, cold working, and by Phase transformation prior to the introduction of nitrogen. It was found that the precipitated nitrides, tentatively identified as Fe16N2, have (100) habit planes. Nucleation takes place Preferentially at dislocations and at subboundaries. It sometimes occurs in the matrix, probably on vacancy clusters, but rarely on high-angle boundaries. The process of nucleation on dislocations and subboundaries is very temperature dependent. At room temperature there is no particular orientation relationship between the dislocations involved and the (100) planes on which the nitride Particles formed. With increasing temperature, the nucleation sites tend to become restricted to those dislocation segments lying in (100) planes. The change of yield stress of the 0.022 and 0.043 pet N alloys during quench aging can be correlated semiquantitatively with the change in particle distribution. Strain aging in quenched alloys can be separated into two stages. The early stage is attributed to nitrogen segregation to dislocations and the later stage is associated with precipitation. When previously quench-aged specimens were strained and aged, no additional Precipitates could be seen, although a considerable amount of strain aging occurred. DURING the past two decades, the precipitation of nitrides from a iron has been extensively studied by various techniques. It has been established that two types of nitride exist. The stable nitride, Fe4N, forms at temperatures above 250oC and Fe16N2, the

Jan 1, 1962

By L. F. Marek, G. W. King, A. Bogrow

THE purpose of this paper is to present the data and some interpretation of the results of a laboratory study of the reduction of iron ore and the deposition of carbon from the reducing gas mixtures in such reductions. One major object of the study was to determine the effect of gas pressures on these chemical processes. Effort was made to approximate the conditions of temperature, gas composition, linear and mass gas velocities, pressure range, and extent of reduction prevailing in commercial blast furnaces. The results show that the reduction of Fe203 proceeds by two steps, largely consecutive under the conditions used herein: reduction of Fe203 to FeO, and reduction Of FeO to Fe. Unless the gas has a CO/CO2 ratio greater than 2.1 only the first step occurs under these conditions (850°C) but the following generalizations apply to either step or to the combination. The rate of reduction of relatively fine ore particles at any time is proportional to the mass rate of supply of CO (provided some of it is thermodynamically available) the rate therefore is proportional to the linear velocity at constant pressure, or to the pressure at constant linear velocity. Thus, the rate of reduction may be increased without increase in linear velocity f the reducing gas by increasing the mass velocity of the gas and increasing the pressure correspondingly to avoid any increase in the linear velocity. The rate "constants"-i.e., the efficiency of conversion of the "available" CO supplied-is not actually constant but decreases as the reduction proceeds, and is a function only of the state of the ore; i.e., of the amount of reduction already accomplished and hence of the amount of CO passed. The particle size Of ore used in nearly all the experiments was relatively small (8 to 14-mesh). The rate of reduction in run 16 with 3 to 8-mesh ore particles is within experimental error the same as with the finer ore. Although this would indicate an absence of effect due to particle size in this range of ore particles, it is desirable to have more data on other ore sizes and on ore of different densities before arriving at any generalizations on this point. Although it is possible to extend the analysis of these results to consideration of the more detailed kinetics and mechanism of iron oxide reduction, such extension is beyond the scope of the present paper. From the experiments on carbon deposition, it was evident that if carbon deposition is increased at all by the application of pressures up to 10 psi ga., such increase appears to be less than the experimental and analytical error. It appears safe to conclude that at top pressures on the order

Jan 1, 1947

By Paul F. Kerr

Uranium mineralization occurs in the footwall of the Sunshine vein from the 2900 to the 3700 level. Veinlets of uraninite associated with pyrite and jasper have been so extensively divided and recemented that units more than a few feet in length are seldom observed. The wall rock is St. Regis quartzite of the Belt series. The age of the uraninite, on the basis of isotopic analyses, is 750 t- 50, which agrees with geological data suggesting that phases of the Sunshine mineralization are pre-Cambrian.

Jan 5, 1953

Jan 1, 1919

Jan 1, 1936

By O. W. Ellis

THE writer has dealt with the effect of various methods of melting copper upon the gas content of the metal.1 The copper referred to in his in his earlier paper was melted in the foundry both in the oil furnace and the electric furnace. As the metal, did not measure up to conductivity FIG. L -INGOT OF OVERPOLEP COPPER. standard, the term "casting copper" was applied to the material in the title of the paper. It was thought that some information in regard to the gases in a sample of overpoled copper might also be of interest, and through the courtesy of C. R. Stevens, superintendent of the copper mill of the Westinghouse Elec. & Mfg. Co., such a sample was obtained. The metal was chill-cast in the form of an ingot about 7 in. long, 2 ½ in. deep (from the base to the raised surface of the ingot) and from 1 3/8 to 1 7/8 in. wide. A photograph of part of the ingot is shown in Fig. 1. The effect of overpoling on the surface of the metal is here quite clearly shown.

Jan 1, 1929

Executive.. CHARLES F. RAND, Chairman. JAMES F. KEMP, JOSEPH W. RICHARDS. ALBERT R. LEDOUX, BENJAMIN B. THAYER. Membership. BENJAMIN B. THAYER, Chairman. WALTER R. INGALLS, JOHN H. JANEWAY, Jr., JOHN D. IRVING, HERMAN A. PROSSER. Finance. EDWARD L, YOUNG, Chairman. KARL EILERS, JAMES GAYLEY. Library. JAMES F. KEMP, Chairman. JOHN HAYS HAMMOND,3 E. GYBBON SPILSBURY,2 ALES. C. HUMPHREYS 4 BRADLEY STOUGHTON.

Jan 7, 1913