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By J. R. Stone, J. T. Roy

ASARC09s continuous tapper for lead blast furnace is described. Its use throughout the company's plants has resulted in higher production rates, lower labor costs, and better working conditions. It has also permitted wide latitude in blast pressures, as well as in charge and slag compositions. The practice of tapping a lead blast furnace has remained essentially unchanged for many years. In principle, it is a batch operation discharging the products from the continuous smelting of lead-bearing materials. As such, it imposes certain restrictions on the proper functioning of the smelting operation. First, it calls for a highly developed sense of timing, and a considerable amount of physical effort on the part of the operator. Dirty and hot working conditions, as well as the hazards of flying metal and slag, usually prevail. These conditions have resulted in higher labor costs, both in rate and in amount. Labor turnover has also been high. Secondly, rigid control of mechanical and metallurgical factors must be maintained. Frequent oxygen lancing of the tap hole is needed to permit tapping, thereby increasing operating costs. Rapid increases in smelting rate, plugged tap holes, or forgetfulness on the part of the operator may permit the molten material to rise above the tuyeies and freeze the furnace. Also, the operator will often blow out the tap hole after draining, filling the area with fume. Composition of charge also vitally affects the tapping. The type of lead-bearing material being smelted will naturally affect the smelting rate, and thus the frequency of tapping. The amounts and types of fluxing materials, which determine the ultimate fluidity of the slag, must be regidly controlled. Finally, the batch tapping of a continuous smelting operation of this type appears to be wrong in principle. The molten material drains into the crucible at the bottom of the furnace where it starts cooling immediately and continues to cool until tapped out. While keeping the lead molten is no particular problem, maintaining a fluid slag at all times is often difficult, and sometimes impossible. These factors all point to the desirability of a method for the continuous tapping of a lead blast furnace. The expected advantages would be more desirable working conditions, lower labor costs, increased production, and a much wider latitude in both blast pressure and charge composition. CONTINUOUS TAPPING Historical. A number of devices, e.g., mechanical tappers, siphons, and lead wells, have been tried in the past in attempting to effect continuous tapping. None proved to be entirely satisfactory for tapping lead and slag simultaneously. It was not until 1955, however, that ASARCO designed and put into operation a successful tapping unit at its East Helena, Mont. lead smelter. This unit is described in detail in U.S. Patent NO. 2,890,951. Continuous Tapping Unit—See Figs. 1 and 2. Fig. 1 is a schematic drawing of the unit in place, showing front and side views. The component parts are identified in the caption. Fig. 2 is an actual photograph, front view, of the tapping unit attached to the base of the blast furnace. Operation. The operation of the tapping unit is quite simple. Essentially it consists of a narrow tapping bay surrounding the furnace tap hole, with a deep notch in the front wall. When the blast furnace is started this notch is open down to the level of the tap hole. Starting the furnace may be accomplished in several ways but the most satisfactory method is to plug the tap hole with clay, permitting metal and slag to build up inside the furnace. Before the liquid reaches the tuyeres, the plug is removed and the furnace is drained to the settler. The blast is then stopped momentarily while the notch in the front wall of the tapping bay is dammed with chrome brick and plastic chrome ore. The blast is again started, and the height of the dam is adjusted so that the liquid in the bay will counterbalance the internal pressure of the furnace. When the desired level is reached the slag and metal will overflow to the settler. It should be noted that the molten material ,is not siphoned from the furnace and that the metal 'acts as a liquid valve controlling the flow of slag through the tap hole. During normal operations the tapping bay is filled primarily with lead, covered with a thin layer of slag. Thus, the heavier lead plays the major role in compensating for variations in furnace pressures. Due to the high specific gravity of lead, changes in the liquid level in the tapping bay will never exceed a few inches. For this reason it is seldom necessary to change the height of the dam due to minor variations in operating conditions. Some turbulence of the liquid in the bay is essential at all times. This indicates that the level of the

Jan 1, 1963

By Betty M. Miller

INTRODUCTION In September 1974 the Resource Appraisal Group of the Branch of Oil and Gas Resources, U. S. Geological Survey, was asked to aid the Federal Energy Administration (FEA) in its legal responsibility to generate by June 1975 an independent appraisal of the undiscovered oil and gas resources of the United States, both onshore and offshore. As a result, the Resource Appraisal Group accelerated its ongoing efforts to develop sound appraisal methods and procedures that would permit the systematic collection and evaluation of basic data from petroleum provinces throughout the Nation. The results of this independent appraisal of the Nation's conventional oil and natural gas resources were published by the U. S. Geological Survey as Circular 725, June 1975 (1). The estimates in this report of undiscovered recoverable oil and gas resources for the United States were made: (1) by carefully re- viewing a large amount of geological and geophysical information gathered on more than 100 different provinces by over 70 geologists within the Survey; (2) by applying a variety of resource appraisal techniques to each potential petroleum province; and (3) by application of subjective probability procedures to group appraisals for each petroleum province. These methods provide a range of estimates which are summarized in terms of low, high and mean values for the various provinces and groups of provinces, or regions. The basic data and procedures used are documented and are being incorporated into a dynamic, data- intensive system that can be upgraded, updated and reevaluated periodically. These data are open to public inspection. In this study, the primary emphasis was placed on conventional crude oil and natural gas in the onshore provinces and the provinces on the continental shelf out to water depths of 200 metres; estimates

Jan 1, 1977

By J. D. H. Strickland, K. J. Jackson

IN previous papers' ' details were given of the constructlon and use of an apparatus to study the rate of chlorine consumption and the rate of sul- fate and sulfur production when dilute aqueous chlorine solutions were allowed to react with pyrite and galena in acid solutions at or near room temperature. The reaction with pyrite was very rapid, and hence entirely transport-controlled in its kinetics, and produced only ferric and sulfate ions. The behavior of galena was much more complex and was studied in some detail. Sulfur monochloride could be detected as a reaction product and both

Jan 1, 1959

By R. G. Knickerbocker

A most important research and development item on ferroalloys in the calendar year of 1949 was the increase of interest in the recovery of secondary manganese. Owing to the importance of manganese to the nation's welfare, it is Ferroalloys most necessary that all possible avenues of research and development on the recovery of this vital metal be investigated. The principal objective of this new development is to recover manganese from steel furnace slags. Steel furnace slags contain a total of approximately 772,000 tons of metallic manganese which is compared to the 680,000 tons of metallic manganese as ferromanganese that is estimated to be used by the steel industry, annually, at this time.

Jan 6, 1950

By J. T. Williams

The equilibria in the V-Zr alloy system were investigated by solidus temperature determinations, thermal analysis, dilatometry, electrical resistance measurements, microscopic examination, and X-ray diffraction analysis. There is a eutectic reaction at 1230°C between a compound, V2Zr, and a solid solution containing 10 pct V in ß zirconium. V2Zr decomposes at 1300°C into liquid and a solid solution containing about 10 pct Zr in vanadium. The eutectic composition is probably about 30 pct V. A eutectoid reaction between V2 Zr and a zirconium takes place at 777°C at a very high rate. The eutectoid composition is 5 wt pct V. The limit of solubility of zirconium in vanadium was estimated to be 5 pct at 600°C. No attempt was made to determine the liquidus for the system. THE recent availability of large quantities of high purity zirconium has stimulated the study of zirconium binary systems. The equilibrium diagram for the V-Zr system has received little attention, however. Wallbauml appears to have made the first report concerning the equilibria in these alloys. He reported the existence of a compound, V2Zr, having the MgZn2 ((214) type of structure with a, = 5.277 kX and c° = 8.647 kX. Anderson, Hayes, Roberson, and Kroll2 made a survey of some potentially useful zirconium binary alloys and found that zirconium probably dissolves a small amount of vanadium. They reported the probable existence of a compound between the two elements and suggested that the zirconium-rich solid solution undergoes a eutectic reaction with this compound. Pfeil," in a critical review of the existing information, estimated that the solubility of vanadium in zirconium is less than 4.7 pct and probably less than 1.8 pct. Rostoker and Yamamoto' proposed a partial diagram for the V-Zr system in a survey paper on vanadium binary alloys. Their diagram indicates the compound, V,Zr, a eutectic reaction at 1360°C, a peritectic reaction at 1740°C, and a limit of solubility of zirconium in vanadium of about 3 pct. They obtained no information on the equilibria in the zirconium-rich alloys. In view of the potential utility of the V-Zr alloys and the incomplete knowledge concerning the equilibria in the system, an attempt was made to establish the constitutional diagram. Preparation of the Alloys Raw Materials: The vanadium for making up these alloys came from the Electro Metallurgical Corp. Zirconium came from two sources. In the beginning of the investigation, sponge zirconium from the Bureau of Mines was used in making some of the alloys. Later, iodide metal made at the Westinghouse Atomic Power Development Laboratories became available. This material was used in the preparation of all the dilatometric and resistance specimens and about two-thirds of the solidus temperature specimens. A typical manufacturer's analysis of the vanadium is shown in Table I. No other analysis of the vanadium was made. The metal contained a dispersed second phase and did not have a sharp melting point. Typical results of spectrographic analysis of the Westinghouse zirconium are shown in Table 11. These data indicate a very high purity. The Bureau of Mines sponge metal was probably less pure but had good ductility. Melting: All of the alloys used in the investigation were made by melting pieces of vanadium and zirconium together in a dc electric arc furnace similar to those of Geach and Summers-Smith, craighead, Simmons, and Eastwood," and others. Melting was done in an atmosphere of helium scavenged of residual air by the preliminary melting of a separate charge of zirconium. Each ingot was turned over and melted at least three more times before removal from the furnace to aid in the attainment of homogeneity. Alloys prepared for use in the investigation are listed with the results of solidus determinations in Table III with the exception of the following compositions upon which no solidus determinations were made: 0.29, 0.54, 4.57, and 5.55 pct V. Analysis: The weight of each ingot made from iodide zirconium was within 0.1 g of the total weight of the initial charge, about 90 g. Since each component of each charge was weighed to the nearest 20 mg for amounts less than 10 g and to the nearest 0.1 g otherwise, the gross composition of an ingot could be calculated accurately. Chemical analysis for the vanadium content of several alloys agreed

Jan 1, 1956

By G. S. Hume

Production of petroleum and natural gas increased in Canada in 1939 principally because of new wells in Ontario and Alberta. Turner Valley The Turner Valley field, Alberta, yielded 7,456,000 bbl. of petroleum in 1939 in comparison with 6,703,548 bbl. in 1938, an increase of 11 per cent. Turner Valley now supplies 96 per cent of all petroleum produced in Canada (Table 1). The Turner Valley field (Table 2) has reached a position where it call supply much larger volumes of petroleum than the Prairie market is capable of consuming. The allowable production is under the jurisdiction of the Petroleum and Natural Gas Conservation Board of Alberta and the daily rate is set from time to time as warranted by the demand. During June the allowable reached a maximum of 27,000 bbl. a day. This, however, was a temporary situation due in part to the completion of a new British American Oil Co. refinery in Calgary capable of processing 5000 bbl. a day and with a storage capacity of about 100,000 bbl. The maximum consumption was reached during the harvest season with

Jan 1, 1940

By G. S. Hume

Production of petroleum and natural gas increased in Canada in 1939 principally because of new wells in Ontario and Alberta. Turner Valley The Turner Valley field, Alberta, yielded 7,456,000 bbl. of petroleum in 1939 in comparison with 6,703,548 bbl. in 1938, an increase of 11 per cent. Turner Valley now supplies 96 per cent of all petroleum produced in Canada (Table 1). The Turner Valley field (Table 2) has reached a position where it call supply much larger volumes of petroleum than the Prairie market is capable of consuming. The allowable production is under the jurisdiction of the Petroleum and Natural Gas Conservation Board of Alberta and the daily rate is set from time to time as warranted by the demand. During June the allowable reached a maximum of 27,000 bbl. a day. This, however, was a temporary situation due in part to the completion of a new British American Oil Co. refinery in Calgary capable of processing 5000 bbl. a day and with a storage capacity of about 100,000 bbl. The maximum consumption was reached during the harvest season with

Jan 1, 1940

By McDowell Graves, Joseph Jensen, W. D. Goold, M. L. Gwin

During the present year the Santa Fe Springs field has proved to be the most important oil field under development in the United States. Its production will exceed that of any other field. Without it, production within the United States would have been almost in even balance with consumption. The field has forced to the fore and compelled, more than any other single factor, serious consideration of the need of conserving the gas resources of the State of California. It has also contributed much to the development of new drilling equipment and important features in petroleum engineering, and has required the development of a new cement for use in deep wells because of high temperatures. It is the only oil field in the country where wells 8000 ft. deep have become so common that they are no longer given special attention. The field covers a little less than 1400 acres of land. In it 196 producing deep-zone wells have already been drilled since August, 1928, and 224 wells are still drilling. More wells may be drilled. This indicates that probably more than 450 wells will be drilled in the present campaign. In hardly a year's time it has caused the outlay of nearly $50,000,000 for drilling, and within the year 1929 it will have returned practically an equal amount of revenue. In contrast to conditions during 1923, when this field was once before an important and disturbing factor, the California oil industry has not been forced to refinance to meet the situation presented by such a large production of oil. There has been practically no unit selling and no stock selling, nor any unnecessary development far beyond the limits of the field. Production is now about 275,000 bbl. per day and gives every promisc of remaining at this figure or increasing to nearly 300,000 bbl. Six months from now the field should still be capable of producing more than 200,000 bbl. per day. Obviously, the need for conserving gas that would be blown to the air, incident to the production of so large a volume of oil, represents a problem in conservation deserving of the most serious attention of the oil industry and of the State of California.

Jan 1, 1930

Map

Jan 1, 1941

By Bernard S. Borie

THE U-A1 binary system has been studied by Kaufmann and Gordon.' They have shown that three intermetallic compounds occur in the system: UAl², UAl², and a third compound tentatively identified as UA15. UA1³ is simple cubic, a, = 4.26A. Its unit cell contains one formula weight, and it is iso-morphous with AuCu³. UA1² is face-centered cubic, a, = 7.72A, with eight formula weights per unit cell. Rundle and Wilson have shown that it is iso-morphous with Cu²Mg.² A Debye-Scherrer pattern of the Al-rich compound indicated a more complex structure than either UA1² or UA1³. The following is a report of an investigation of the crystal structure of this compound and a determination of its stoi-chiometric formula. A melt of uranium (99.9 pct pure) and aluminum (99.9 pct pure) was prepared which contained about 25 pct U by weight. It was cooled from 950" to 650°C at a rate of 500" per hr and then taken from the furnace and air cooled. An X-ray diffraction pattern of the ingot showed only lines of aluminum and the Al-rich compound. Filings from the ingot were reacted with a solution of sodium hydroxide, producing a fine black powder, the diffraction pattern of which showed no traces of aluminum. A comparison of the Debye-Scherrer pattern of our sample with the data published by Kaufmann and Gordon1 showed that it is identical with the Al-rich phase which they reported. Single crystals were obtained by cooling the melt more slowly (about 50°C per hr). After reaction with sodium hydroxide, the crystals appeared as small black needles attached to the ingot surface. Cell Size, Space Group, and Uranium Positions A series of Weissenberg photographs for rotation about two of the crystallographic axes, taken with copper radiation filtered through nickel foil, revealed an orthorhombic cell of dimensions: a = 4.41 ± 0.02A b = 6.27 ± 0.02A c = 13.71 ± 0.03A Reflections of the type hkl were observed only if: h + k + I = 2n, of the type hkO only if: h = 2n and k = 2n, of the type h01 only if: h + 1 = 2n, and of the type Okl only if: k + 1=2n. Hence, the cell is body-centered with an 001 glide plane. The evidence for the existence of the glide plane is the observed extinction of 23 possible re- flections of the type hkO with at least one index odd. There are only two space groups consistent with these data: C"" — I2ma and D28 2h — Imma.³ he possible sets of atomic positions for these space groups are: 12ma: (0 0 0; ½ ½ ½) + 4: (a) x 0 %; x % % (b) x ¼ z; x ¾ Z 8: (c) x y z; x y z; x, ½ + y, Z x, M - y, z Imma: (0 0 0; ½ ½ ½) + 4: (a) 0 0 0; 0 ½ 0 (b) 0 0 ½; 0 ½ ½ (c) ¼ ¼ ¼; ¾ ¼ ¼ (d) ¼ ¾ ¾ ; ¾ ¾ % (e) 0 ¾ Z; 0 ¾ z 8: (f) x 0 0; x 0 0; x 1/2 0; x ½ 0 (g) ¼ Y ¼; ¾ Y ¾; ¾ y ¼; 1 y ¼ (h) 0 y z; 0; ;; 0, ½ + y, z; 0, l/2 - Y, Z (i) x 1/4 z; x ¾ z; ¼ z; x ¾ z 16: (j) xy z; x y z; x y z; x y z; x, ½ + y, Z; x,½ - y, z; x, ½ - y, z; 11 1, + y,Z Though density measurements on different samples were found to vary somewhat, they were all within the range 5.7 * 0.3 g per cu cm. If it is assumed that the unit cell contains four formula weights of UAl,, it is 6.5 g per cu cm. If there were as many as eight uranium atoms per unit cell, the

Jan 1, 1952

JUST as I have told you that it is impossible to give an exact rule for the bell scale, so I say the same concerning the clappers. Yet, if one wishes the bell to sound well, it is necessary that it have a proportioned blow; for if it is struck with a clapper that is lighter than it should be, it will not give out all the sound that it contains, and if it is struck with a heavier one than it can support, it is forced and the sound is made crude and harsh, in addition to the danger of breaking the bell. Therefore-the clappers must be made so that they bear a certain proportion to the bell, and in order not to proceed by chance, I have diligently tried to find the method as well as possible. I have found that experienced masters [99] have given to bells weighing ten pounds a clapper of one and a half pounds [and, to larger ones, clappers as tabulated on the next page].* Larger numbers than these I have not found because, in truth, few of the extraordinarily large ones are made in our regions. In my opinion, the masters should not be limited to these rules for the differences in clappers but should proceed according to the kind of bell, using a certain discretion for it is not possible to give a definite rule.

Jan 1, 1942

By Charles E. Locke

PROSPERITY of the gold miner has continued with attendant construction of numerous plants, many of them small but some of good size. Many new mills have been erected in Canada and in the Philippines, end one should mention the new mill at Cripple Creek, Colo., a custom plant allowing a choice of flotation, cyaniding, or roasting and cyaniding. Flotation is a feature of many of the new plants and some existing mills have been remodeled to use flotation in place of amalgamation and cyaniding. The Utah Copper Co. has re- opened its Arthur mill and operations are being resumed in the big Ray, Chino, and Inspiration copper mills. Examples of new construction are the Mountain City 300-ton copper flotation mill in northern Elko County, Nevada; the Star zinc mill and one or two other mills in the Coeur d'Alene district of Idaho; and the 500-ton mill for the Buena Vista mine at Stewart, B. C. The last-named is to be installed underground, following the example of the zinc mill at Gilman, Colo., and he small Doyle jigging plant in the Wisconsin zinc fields.

Jan 1, 1937

By H. E. Crum, W. E. Hubbard

This review covers the northern 32 counties of the Texas Panhandle, an area 180 miles square. The westerly three-fourths of the district lies wholly within that great area known as the Llano Estacado or "staked plains." Six of the counties produce oil and gas and three produce gas alone. All of the production is associated with the Amarillo arch, a huge anticline superimposed upon a buried mountain range which is undoubtedly a continuation of the Wichitas of southwestern Oklahoma. Oil Production The production of the Texas Panhandle up to Jan. 1,1930, was slightly over 157 million barrels, 90 per cent. of which came from Hutchinson and Gray counties. About 33,000,000 bbl. was produced during 1930. Though this was about 9 per cent. above the 1929 production, it was over 8,000,000 bbl. less than was produced during the peak year, 1928. The present daily production is slightly over 40,000 bbl., which is the allowable production under state-wide proration. The assumed potential for the purpose of proration is 124,500 bbl. and the actual capacity of the wells probably would be in the neighborhood of 100,000 barrels. The total initial production of the oil wells completed in 1930 was 157,289 bbl. from 308 wells, or 511 bbl. per well, as compared to a 734-bbl. average from the 350 oil wells drilled during the preceding year. The completions in Gray County numbered 232, with an average initial of 614 barrels. Completions During 1930, 526 wells were completed in the Panhandle as compared to a total of 503 during 1929. Of the year's completions, 308 were oil wells, 169 produced gas and 49 were dry holes. Of the 3027 wells drilled in the Panhandle to date, 2780 have produced oil, gas or both, making the ratio of dry holes to producers about 1:11.3. Ignoring the 63 dry holes drilled in nonproductive counties, the ratio becomes 184:2780 or 1:15.1 which is slightly less favorable than that which obtained at the end of 1929.

Jan 1, 1931

By O. C. Wheeler

The principal interest in the oil situation in Colombia during the year centered around the enactment of the new petroleum law and the applications for concessions subsequently made by various interests. The year was a comparatively uneventful one from the standpoint of actual operations of drilling and development. There was a falling off both in exploratory work and in the development of producing properties; and as a result of curtailment of production, the output of oil from the country dropped to the lowest level since the completion of the looping of the Andian pipe line to the coast in 1927. Legislation Law No. 371 of 1931, with its Regulatory Decree No. 1270, was enacted during the year and marked Colombia's attempt to encourage more extensive exploration and development of the prospective oil resources of the country. Some of the outstanding provisions of the law are as follows: Tracts may be acquired by a concessionnaire directly and by transfer ranging from 5,000 to 100,000 hectares, except in certain reserved territories east of the summit of the eastern cordilleras where the maximum is increased to 200,000 ha. A security deposit of $1 per hectare, minimum $25,000, is required on government grants, and is returned to the concessionnaire only upon the fulfillment of stipulated terms of the law. Rentals, increasing progressively from 10c per hectare per year the first two years to 50c per hectare the sixth year, are required up to the start of the production period (beginning of development). The concession terminates 30 years after the beginning of the production period and can be extended for 10 years more at the option of the contractor. Wells must be produced at no less than 25 per cent of their maximum capacity. Royalties on oil from national lands vary from 2 to 11 per cent of the gross product, depending on the distance of the concession from the port of loading. Petroleum from private property is subject to a governmental tax varying from 1 to

Jan 1, 1932

By Eugene McAuliffe

THE Coal Division undertook its most ambitious program this year at the New York meeting, with six full' sessions and a luncheon on Monday which had a record attendance and at which the newly elected officers for the Division were announced. Eugene McAuliffe, president of the Union Pacific Coal Co., Omaha, Neb., was unanimously selected as Chairman; J. B. Morrow, preparation manager of the Pittsburgh Coal Co., as Vice-Chairman; and H. E. Nold, Ohio State University, Secretary. During the past year two new and interesting activities were conducted by the Division directed at stimulating the interest of junior and student members. Reports were presented at the luncheon meeting by the chairmen of these commit¬tees. J. B. Morrow. chairman of the paper prize awards, and H. N. Eavenson reported on the work of the mining machinery manufacturers fellowship, the work on which was completed the first of the year. Several excellent papers are expected from these two groups for the next meeting of the Division to be held in Pittsburgh some time in the fall. The regular six-session program was filled from start to finish with interesting papers and much discussion, but unfortunately not enough time for the latter. The papers covered the field of prospecting, mining methods, preparation, utilization, mechanization, and safety, and all through the program we were constantly reminded of the value and need of research in the coal industry.

Jan 1, 1936

By R. F. Mehl, G. T. Horne

Diffusion coefficients and mobilities were determined as functions of concentration in the a phase of the Cu-Zn system. Use was mode of incremental diffusion couples to determine the Kirkendall effect at various concentrations. Darken's analysis was used to calculate the individual diffusion coefficients and mobilities from these data. The general diffusion coefficient is a single-valued function of the concentration in this system to within the limits of accuracy of the experimental methods used. The form of the various functions (diffusion coefficients and mobilities) of concentration is the same in every case: it is essentially the same as the usual D vs c curve. AS Darken' has pointed out, the knowledge that the movements of different atoms diffusing in the same lattice need not proceed at the same rate is old. Ionic lattices are the classical examples; application of the generalization to lattices with metallic bonding was much more slowly accepted. It remained for Kirkendall'' to show clearly that metallic diffusion need not be symmetrical with respect to both species. Several investigators" have confirmed the initial observation of a "Kirkendall effect:" marker movement accompanying diffusion. They have extended it to other systems and conditions. The theoretical interpretations have been many; ne of the first and simplest of these is that of Darken"' which is essentially mechanism independent. Darken has shown that the Kirkendall experiment permlts a calculation of the individual diffusion coefficients and, coupled with activity data, offers a means of measuring the mobilities of the separateatoms in a binary diffusion process. There is no published information on the effects of concentration and temperature on the individual diffusion coefficients or on the mobility values in binary solid solution; this paper provides such information for zinc and copper in a brass. For purposes of clarity, the overall D value obtained, for example, from the Boltzmann-Matano solution to Fick's law, will be designated as the "general diffusion coefficient;" and the diffusion co- efficients for the separate diffusing species will be designated as the "individual diffusion coefficients." Experimental Procedure The authors have accepted Darken's analysis and have measured mobilities on this basis. The findings of da Silva and Mehl are accepted: that the Matano interface, defined as the origin of coordinates for the Boltzmann-Matano solution to Fick's law, coincides with the original weld interface; that the "shift" of a marker is the distance between the Matano interface and the marker; that the observed porosity is too small sensibly to affect this result; and that the shift is a linear function of the Matano area, the area defined as the absolute magnitude of the area on either side of the Matano interface. Alloys: The a-phase of the Cu-Zn system was chosen for investigation. The measurements were made on incremental couples for two separate reasons: l—it has been questioned whether D, the general diffusion coefficient, is a single-valued function of concentration (a comparison of the D-values for couples with small concentration range, e.g., 10 vs 20 pct Zn, against those from a wide concentration range, e.g., 0 vs 30 pct Zn, will answer that question); and 2—on the Darken analysis, the mobility can be determined only at the concentration at which the marker is observed to lie (this is but one concentration in a single couple) but choosing a series of incremental couples in the range between 0 and 30 pct Zn provides mobility values at several concentrations, thus giving mobility as a function of concentration. Four alloys were chosen; nominally, pure copper, copper with 10 pct Zn, copper with 20 pct Zn, and copper with 30 pct Zn. This allowed six different types of diffusion couples to be prepared, promising mobility determinations at six different concentrations, but having a minimum range of 10 pct Zn. The copper was an especially prepared pure copper supplied through the courtesy of the Ameri-

Jan 1, 1956

By M. D. Hassiallis

The claim is made in a number of patents1'2'3'4 that some compounds of the class known as aryl sulphides have collector properties. One of these patents generalizes the claim to include all aryl sulphides, whose generic formula is R-S2-R' (where x = 1,2, . . . ), with the restriction that if the aromatic radicals R, R' contain substituent groups these groups may not contain nitrogen or oxygen. Moses, Hess, and Perkins cite as evidence for their claims the results of flotation tests on Anaconda and Miami copper ores using diphenyl sulphide, ditolyl disulphide and dinapthyl disul-phide as collectors. The use of alkyl sulphides as collectors has also been reported5 with the conclusion that the alkyl sulphides are better collectors than the corresponding aryl sulphides. The experimental work cited appears to confirm this contention. In order to test these claims with respect to diphenyl sulphide, a sample, purchased from the Eastman Kodak Co., was tested against Anaconda ore. The procedure followed. was that of Moses, Hess, and Perkins. A sample of ore weighing 500 • grams was placed in a laboratory ball mill. To this was added 220 grams of water, 0.06 grams of commercial diphenyl sulphide (1/4 lb. per ton of ore), and 0.8 grams of lime (3 lb. per ton of ore). The material was ground until 93 per cent passed a 65-mesh screen. This pulp was diluted to 16 per cent solids. A sample of the diluted pulp was placed in a Minerals Separation type of laboratory flotation cell. After a a-min. agitation period, pine oil was added and the froth collected for a period of 15 min. This test recovered 68 per cent of the copper, with a ratio of concentration of 6.8:I. The tailing assay was 0.3 per cent Cu. Moses, Hess and Perkins attained a recovery of 75 per cent, with a ratio concentration of I2:I. Although these results do not compare too well with those of Moses, Hess and Perkins, subsequent tests showed an improvement, as judged by vanning of the tails. It is concluded, therefore, that the patent results are confirmed. Contact-angle Tests In order to study the response of the various minerals, found in Anaconda ore, to commercial diphenyl sulphide, some contact-angle tests were made. Polished particles of bornite, chalcodte, chalco-pyrite, pyrite and quartz were conditioned for 15 min. in a suspension of diphenyl sulphide in water. The concentration of this suspension was 0.284 grams per liter, this being the concentration of this reagent in the ball mill. The conditioned particles were rinsed with water (not rubbed with filter paper or boiled linen) and then tested against an air bubble in the bubble machine, with the following results: born-

Jan 1, 1943

By M. D. Hassialis

THE claim is made in a number of patents1,2,3,4 that some compounds of the class known as aryl sulphides have collector properties. One of these patents generalizes the claim to include all aryl sulphides, whose generic formula is R-S¬R[=]-R’ (where x = r,2, . . . ), with the restriction that if the aromatic radicals R, R' contain substituent groups these groups may not contain nitrogen or oxygen. Moses, Hess, and Perkins cite as evidence for their claims the results of flotation tests on Anaconda and Miami copper ores using Biphenyl sulphide, ditolyl disulphide and dinapthyl disulphide as collectors. The use of alkyl sulphides as collectors has also been reported5 with the conclusion that the alkyl sulphides are better collectors than the corresponding aryl sulphides. The experimental work cited appears to confirm this contention. In order to test these claims with respect to diphenyl sulphide, a sample, purchased from the Eastman Kodak Co., was tested against Anaconda ore. The procedure followed was that of Moses, Hess, and Perkins. A sample of ore weighing 500 grams was placed in a laboratory ball mill. To this was added 220 grams of water, 0.06 grams of commercial diphenyl sulphide (1/4 lb. per ton of ore), and 0.8 grams of lime (3 lb. per ton of ore). The material was ground until 93 per cent passed a 65mesh screen. This pulp was diluted to 16 per cent solids. A sample of the diluted pulp was placed in a Minerals Separation type of laboratory flotation cell. After a 2-min. agitation period, pine oil was added and the froth collected for a period of 15 min. This test recovered 68 per cent of the copper, with a ratio of concentration of 6.8: 1. The tailing assay was 0.3 per cent Cu. Moses, Hess and Perkins attained a recovery of 75 per cent, with a ratio concentration of 12: 1. Although these results do not compare too well with those of Moses, Hess and Perkins, subsequent tests showed an improvement, as judged by vanning of the tails. It is concluded, therefore, that the patent results are confirmed. CONTACT-ANGLE TESTS In order to study the response of the various minerals, found in Anaconda ore, to commercial diphenyl sulphide, some contact-angle tests were made. Polished particles of bornite, chalcocite, chalcopyrite, pyrite and quartz were conditioned for 15 min. in a suspension of diphenyl sulphide in water. The concentration of this suspension was 0.284 grams per liter, this being the concentration of this reagent in the ball mill. The conditioned particles were rinsed with water (not rubbed with filter paper or boiled linen) and then tested against an air bubble in the bubble machine, with the following results: born-

Jan 1, 1943

By M. D. Hassiallis

The claim is made in a number of patents1'2'3'4 that some compounds of the class known as aryl sulphides have collector properties. One of these patents generalizes the claim to include all aryl sulphides, whose generic formula is R-S2-R' (where x = 1,2, . . . ), with the restriction that if the aromatic radicals R, R' contain substituent groups these groups may not contain nitrogen or oxygen. Moses, Hess, and Perkins cite as evidence for their claims the results of flotation tests on Anaconda and Miami copper ores using diphenyl sulphide, ditolyl disulphide and dinapthyl disul-phide as collectors. The use of alkyl sulphides as collectors has also been reported5 with the conclusion that the alkyl sulphides are better collectors than the corresponding aryl sulphides. The experimental work cited appears to confirm this contention. In order to test these claims with respect to diphenyl sulphide, a sample, purchased from the Eastman Kodak Co., was tested against Anaconda ore. The procedure followed. was that of Moses, Hess, and Perkins. A sample of ore weighing 500 • grams was placed in a laboratory ball mill. To this was added 220 grams of water, 0.06 grams of commercial diphenyl sulphide (1/4 lb. per ton of ore), and 0.8 grams of lime (3 lb. per ton of ore). The material was ground until 93 per cent passed a 65-mesh screen. This pulp was diluted to 16 per cent solids. A sample of the diluted pulp was placed in a Minerals Separation type of laboratory flotation cell. After a a-min. agitation period, pine oil was added and the froth collected for a period of 15 min. This test recovered 68 per cent of the copper, with a ratio of concentration of 6.8:I. The tailing assay was 0.3 per cent Cu. Moses, Hess and Perkins attained a recovery of 75 per cent, with a ratio concentration of I2:I. Although these results do not compare too well with those of Moses, Hess and Perkins, subsequent tests showed an improvement, as judged by vanning of the tails. It is concluded, therefore, that the patent results are confirmed. Contact-angle Tests In order to study the response of the various minerals, found in Anaconda ore, to commercial diphenyl sulphide, some contact-angle tests were made. Polished particles of bornite, chalcodte, chalco-pyrite, pyrite and quartz were conditioned for 15 min. in a suspension of diphenyl sulphide in water. The concentration of this suspension was 0.284 grams per liter, this being the concentration of this reagent in the ball mill. The conditioned particles were rinsed with water (not rubbed with filter paper or boiled linen) and then tested against an air bubble in the bubble machine, with the following results: born-

Jan 1, 1943

Jan 1, 1935