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By W. R. Ingalls

During the last two years, and especially during the last six months, a number of important articles upon the new methods for the desulphurization of galena have been published in the technical periodicals, particularly in the Engineering and Mining Journal and in Metallurgie. I proposed for these methods the type-name of " lime-roasting " of galena as a convenient metallurgical classification,'and this term has found some acceptance. The articles referred to have shown the great practical importance of these new processes, and the general recognition of their metallurgical and commercial value which has already been accorded to them. It is my present purpose to review broadly the changes developed by them in the metallurgy of lead, in which connection it is necessary to refer briefly to the previous state of the art.

Jan 1, 1907

By J. F. Nicholas

THE angles between the crystallographic planes in cubic metals were originally given by Bozorth and have been republished many times. Recently, Salkovitz2 tabulated the angles for the hexagonal metals (magnesium, zinc, and cadmium). he most commonly used metal which does not fail into either of these groups is tin, which has a tetragonal structure with an axial ratio of c/a = 0.54558 (99.99 pct purity, 25°C).² ccordingly, Table I has been prepared giving the possible values for the angle, 4, between planes of the types {HKL) and {hkl). The formula used was: Hh + Kk + LI — cos? = —--------------—-----------— A [(H2 + K2 + L2-a2c2(h2 + k2 + r;)] All angles are given correct to the nearest minute as this is sufficient for all practical purposes. Every angle depends in a different way on variations in the value of c/a, but even in the worst cases a variation of about 0.0003 in this ratio is needed to vary an angle by l', which corresponds to a temperature change of 20 °C or can be caused by impurities.

Jan 1, 1952

In accordance with the requirements of our By-Laws I beg leave to submit herewith the report of the Library Committee for the year 1915. The activity shown by the sale of the institute publications during the year continues satisfactory, although not as large as last year. The total sales amount to $6,666.81, distributed as follows: Sale of Transactions...:: :. $4,585.42 Sale of Special Editions 553.17 Sale of Pamphlets and Bulletins 2,028.22 It should-be borne in mind that the sale of special editions was only begun last year,, and most of the members who did not have the special editions immediately bought them for their libraries. This year only a little less than half of the same number have been disposed of, and it is more than probable that from now-on the number will be considerably lessened.

Jan 2, 1916

By D. Swan

Industrial research may be defined as a critical and exhaustive investigation to create new and better ways of doing things. The results of industrial research are new and improved products, processes, and techniques. This broad definition, of course, covers investigation of all subjects by either individuals or groups of people, and this chapter aims to examine the purpose (what research tries to do), and methods (or how research is done) as applied in the mineral industries. Concepts and History The idea or concept of organized research probably originated in the universities of Europe. There, groups of scholars banded together for discussion and application of their particular specialty to a common problem. Publication of the conclusions drawn from such investigations gave scholars in other areas the opportunity to review and criticize the work of their colleagues, and one of the hallmarks of scientific research work is the publication and criticism of the results of the investigation. It was not until the late nineteenth century that the concept of organized research for the profit of industry was recognized. During the late nineteenth and early twentieth centuries, a large number of industrial enterprises sponsored organizations to study the application of the physical sciences with the aim of making discoveries that would result in profit to the sponsoring organization. The tangible benefits accruing from these activities were so great that they, in turn, fostered several other methods for the support of organized research activities. For the large problems involving public interest, United States Government scientific research laboratories were set up. As the demand of smaller enterprises for research activities increased, research institutes and consulting laboratories were organized. In Europe the idea of common industry sponsorship of research centers grew and many large research organizations there were sponsored by associations of manufacturers. Finally, in the United States

Jan 1, 1964

By E. A. Beck

(New York Meeting. February, 1913.) For a number of years many attempts have been made to use thermit in order to do away with piping in ingots. Some of these attempts were successful, while others did not give the expected results. Nearly every plant had its own method of using the thermit, and no special care was taken to study, the results or to find the causes for lack of success. Formerly the principle of the process was to decrease the piping by introducing a can filled with thermit, attached to an iron rod, into the head of the ingot directly after it bad been poured. In this case the thermit reaction took place in the upper part of the ingot, and it was thought that through the heat produced the head would keep liquid longer and piping thus be reduced. In other words, the aim was to keep the head of the ingot open by making use of the heat of the thermit reaction, which would thereby give the gases in the steel sufficient time to escape. This result can be attained by the application of a large enough quantity of thermit, but it would not be economical in general practice, and could only be used for high-grade material. Many steel-makers abroad and in this country have had this experience. The Th. Goldschmidt A. G., Germany, has, therefore, made a special study of this question with the co-operation of a well-known steel company, and has worked out a new method for. the application of thermit for this purpose. The results obtained have been most satisfactory and reliable, and this- process is now used in Germany on a large scale in many prominent steel-works.

Jan 4, 1913

By Richard L. Seal, Allan L. Turner

INTRODUCTION The chapter discusses the procedures and operations starting with the actual training of operations personnel with respect to a grinding mill circuit and a typical check-out and start-up of a grinding circuit before turning over the operating circuit to production personnel. For the purposes of this paper, it will be assumed that the mill circuit installation is at a new location or a new operation at an existing operation. Expansion of an existing grinding facility would probably require less time-consuming and less costly procedures than those that will be outlined here. There are numerous arrangements and types of equipment that can be used for grinding circuits. For example, the grinding could be wet or dry. The grinding mill could be a rod or ball mill or some combination. The circuit could be open or closed. The closed circuit classification could be accomplished with rake classifiers, spiral classifiers, cyclones, stationary screens, or vibrating screens. To limit the discussion, the grinding circuit shown on Figure I will be discussed. The circuit includes a dry ore feed by a belt conveyor (feeder) to a wet ball mill. The ball mill discharges to a cyclone feed pump box and pump. The pump feeds a cyclone type classifier with the cyclone underflow returning to the ball mill feed and cyclone overflow being the required grinding circuit product. For the purposes of this paper, it will also be assumed that the extensive overall preparation necessary for every start-up has been accomplished. These preparations are only outlined here as they have been adequately dealt with in recent papers. (1), (2), (3) The items in these preparations would include. 1. Appointment and indoctrination of the start-up organization. 2. Integration of the start-up into the overall project schedule. 3. Development of the specific start-up schedule. 4. Budget determination and monies appropriation.

Jan 1, 1982

By J. W. Snavely

WITH all the advantages of handling bulk materials by means of belt conveyor also go some problems, one of the most persistent being that of cleaning. When sticky materials are being carried; the build-up of material on the return idler rolls results in difficulty of belt training. Much attention has been given to the problem of cleaning conveyor belts, and a great variety of cleaning devices have been developed. Even the best involve troublesome maintenance, and none can completely remove the fine particles imbedded in the belt cover, which cause rapid wear of the return idler rolls, and at the same time, of the belt cover as well.

Jan 12, 1951

By Kingman, Robert I.

SUFFICIENT testing has been .performed with the Dutch State Mines Cyclone for thickening and desliming flotation feed at the concentrator of the National Lead Co., Tahawus, N. Y., to prove its application for this work. It is the purpose of this article to present some of the test results, operational details and advantages of cyclone thickening and classification. The metallurgy of the mill operation was described by Frank R. Milliken, assistant manager of the titanium division.

Jan 1, 1950

By C. T. Bischoff

DURING the past few years geochemical testing for traces of heavy metals in water, soil, rock, and vegetation has aroused increasing interest. Various techniques for field and laboratory determinations have been described in the literature, as have some of the results of application. However, little information has been published regarding application to glacial terrain. Over 90 pct of the Canadian Shield is overburdened, resulting in high costs for mineral exploration once the outcropping ore deposits have been found. This has been largely responsible for the widespread application of mining geophysics in Canada, permitting concentration of effort on area or zones considered most favorable. However, geophysical interpretation has its limitations, since at least 90 pct of the structures indicated thereby contain no valuable minerals. A more direct approach is therefore highly desirable. If underlying base metal mineralization can be detected by sampling soil or vegetation at moderate cost this should prove of great help in locating new discoveries or extending known ones. A large proportion of Canadian ore deposits contain appreciable copper or zinc, even where these are not the principal economic metals. Consequently the field of application is a broad one.

Jan 1, 1954

By Walter Knox, J. D. Doherty

IN 1939, at the request of The Koppers Coal Co., the Koppers Company Research Department established a Stoker Coal Research Laboratory for the purpose of investigating the performance characteristics of stoker coals in typical domestic stoker installations. Fig. I is a photograph of part of the laboratory. The material in this paper deals with the performance of one coal in a single installation. Presented are details of this installation, mechanical characteristics of the stoker, and the results of a series of burning tests in which adjustments were systematically varied. SUMMARY OF RESULTS Mechanical Features I. A large percentage of the total power consumed by a domestic stoker is used to operate the gear case and motor (Fig. 3). 2. The power consumption per ton goes down with an increase in rate of coal feed (Fig. 4). 3. The automatic air control in this stoker showed advantages over manual control (Fig. 5). 4. The air velocities through the retort tuyeres were uniform around the retort, but varied between the rows of tuyere rings (Fig. 6). 5. The crushing of coal with this stoker increased the minus 1/8-in. from 1 1.6 per cent to 19.2 per cent. There was a noticeable segregation of coal as it came from the retort and distribution was not uniform (Fig. 7). 6. Measurement of air entering over the fire showed that with some not uncommon adjustments this air may he a high percentage of the total air supply (Fig. 8 and Table I). Operating Performance I. The removal of clinker was shown to give a period of poor performance characterized by a high fuel-bed resistance and a high percentage of carbon monoxide in the flue gases (Fig. 10). 2. The fuel-bed resistance was found to decrease as the fuel bed built up in a normal response to heat demand after a prolonged hold-fire (Fig. II). 3. With intermittent operation the burning rate was almost always less than the feeding rate. The wide variations were found to be greatly dependent upon the length of the On period and the length of the intervals between On periods (Fig. 12). 4. The maintenance of a low furnace draft led to less fly ash, better clinker formation, and higher efficiencies (Fig. I3). 5. The maintenance of a minimum of excess air also resulted in less fly ash, better clinker formation, and higher efficiencies (Fig. 14). GUIDING PRINCIPLES In planning the investigations, the following principles were adopted: Selection of Healing Equipment.-Use only standard models of stokers and furnaces representative of those widely used.

Jan 1, 1942

By S. F. Turcotte, B. J. Grierson

At the Q. I. T. ilmenite smelter, nine electric furnaces produce titania slag and iron At high power levels, a furnace requires either a slag or an iron tap approximately once an hour, using rail cars as slag receptacles and ladles for iron. The correct scheduling of taps is an important operational tool due to peak power load and operational considerations. Over recent years, large increases in furnace capacity have imposed severe strains on the product handling facilities. This situation results in loss of production when several taps are bunched, because of an in- ability to handle many taps simultaneously. An on-line computer program has been developed to generate schedules for tapping a single furnace. By improved scheduling, this program can en- large the tonnage of each tap and minimize the number of taps, while reducing traffic congestion and unit cost s. Future plans call for extension of this technique to all nine furnaces with addition of a master scheduling program to optimize the overall traffic flow in the smelter aisle.

Jan 1, 1969

By AIME AIME

Council.* PRESIDENT O. THE COUNCIL. JOHN HAYS HAMMOND NEW YORK, N. Y. (Term expires February, 1909.) VICE-PRESIDENTS OF THE COUNCIL. SAMUEL B. CHRISTY BERKELEY, CAL. JOHN A. CHURCH NEW YORK, N. Y. PEPSIFOR FRAZER PHILADELPHIA, PA. (Term expires February, 1909.) J. PARKE CHANNING NEW YORK, N. Y. FREDERICK W. DENTON PAINESDALE, INCH. JOHN B. FARISH DENVER, COLO. (Term expires February, 1910.)

Jan 5, 1908

By AIME AIME

Council.* PRESIDENT OF THE COUNCIL. JOHN HAYS HAMMOND* New York, N. Y. (Term expires February, 1909.) VICE-PRESIDENTS OF THE COUNCIL. SAMUEL B. CHRISTY BERKELEY, CAL. JOHN A. CHURCH NEW YORK, N. Y. PERSIFOR FRAZER PHILADELPHIA, PA. (Term expires February, 1909.) J. PARKE CHANNING NEW YORK, N. Y. FREDERICK 1V. DENTON PAINESDALE, MICH. JOHN B. FARISH DENVER, COLO. (Term expires February, 1910.)

Mar 1, 1908

Discussion of the paper of THEODORE P. HOLT, presented at the Salt Lake meeting August, 1914, and printed in Bulletin No. 91, July, 1914, pp. 1699 to 1708. F. S. SCHMIDT, Salt Lake City, Utah.-Any furnace that can make a chloridizing roast to yield an extraction of 92 to 93 per cent. and do this at a cost of less than 24c. per ton in a 10-ton unit opens great possibilities for the treatment of certain classes of ores. This cost does not include the salt and will be reduced to about 16 1/2c. per ton in the 35-ton furnace which are now being designed. On a trial run the roaster treated 9.6 ton: of Ontario stope fillings crushed to pass a ¼ -in. opening. The ore is well adapted to chlorination with the exception of insufficient sulphur and occasional days of high lime, but is not adapted to any other process The following is an analysis of the crude ore: Ag, 9.52; Au, 0.029 oz. Pb, 0.71; Cu, 0.11; SiO, 79.4; Zn, 0.57; S, 1.00; Fe, 7.9; Mn, 0.89 CaO, 1.20 per cent. The composition of the mix was: Per Cent. Dry crude ore : 83.4 Moisture 4.4 Salt 8.3 Coal dust 2.3 Pyrite, 70 per cent. pure 1.6

Jan 11, 1914

PRESIDENT GEORGE OTIS SMITH, District 4 WASHINGTON, D. C. PAST PRESIDENTS SAMUEL A. TAYLOR, District 3 PITTSBURGH, PA. E. DEGOLYER District 0 NEW YORK, N. Y. FIRST VICE-PRESIDENT W. H. BASSETT District 1 WATERBURY, CONN. TREASURER KARL FILERS NEW YORK, N. Y.¬ SECRETARY H. FOSTER BAIN NEW YORK, N. Y.

Jan 1, 1923

By J. David Lowell

For the first time in several years, Chile is again opening its doors to foreign investment. In its new investment code, the Chilean government has announced its willingness to become a partner in joint Chilean-foreign projects for a number of government-controlled porphyry copper deposits at the developed, semi-developed, or prospect stage; and, that it will allow privately owned deposits or deposits discovered by new exploration to be developed with up to 100% foreign ownership. Three deposits of particular interest are: El Abra, with at least 300 million mt of +100% Cu; Los Pelambres, with at least 428 million mt of 0.78% Cu and 0.03% Mo; and Andacollo, with 350 million mt of 0.70% Cu and 0.015% Mo. (El Abra is almost entirely government- controlled; but both Los Pelambres and Andacollo are mostly under private ownership.)

Jan 11, 1974

By Walter Nummela

This acronym may be readily deciphered, and it represents the programming theme for the SME Sessions at the Centennial Meeting of AIME in New York in 1971. The Concentration Committee thus charged out to grab, to induce, and to accept volunteered papers within that framework. The program for the Concentration sessions is in and hopefully all deadlines will be met as specified in the instructions to authors. Without spelling out what is to be seen and heard in New York, how well did the Committee satisfy the theme described in the title? Perhaps it was by virtue of the international makeup of the Committee (Member Dan Pickett is with the Mines Branch in Ottawa) that an international slate of authors was assured. Four countries are to be represented-Bolivia, Canada, Italy, and the United States.

Jan 1, 1970

By R. H. Thorpe

Longwall working in Britain developed to overcome problems arising from depth of seams causing roof and ventilation difficulties. This system became very widespread particularly in the thicker seams, where faces of up to one mile in length were not uncommon. In the thinner sections, in order to remain competitive, the longwall undercutting machine was developed. Following the development of the coal cutter, every other aspect of the face operation was examined and mechanized as it became a bottleneck to output and efficiency. The face system itself was modified and workings concentrated with the same objectives.

Jan 1, 1977

Discussion of the paper of P. B. LIEBERMANN, presented at the St. Louis meeting October, 1917, and printed in Bulletin No. 127, July, 1917, pp. 1051 to 1062. P. B. LIEBERMANN.-As mentioned in my paper, a special investigation was made on the effect of dirt on the track, for the -express purpose of educating mine operators to the advantage of keeping their tracks clean. As to the benefit of clean tracks to the saving in battery consumption, that can be easily determined if the rate of discharge is known under existing conditions, that is, on dirty tracks. The tests have shown that tracks covered with coal dust cause an increase in draw-bar pull of about 30 per cent. The battery discharge table will show the capacity corresponding to the new rate of discharge and will thereby disclose the possible saving in battery consumption. The difference between dirty tracks and clean tracks will be found large enough to have an appreciable effect on the size of the storage-battery locomotive, and for a locomotive of any given size it may mean

Jan 1, 1918

By Reynold Q. Shotts

Chemical methods, based on the relative rates of oxidation of fusain, bright coal, and dull coal by nitric acid, have been devised to determine these coal components.1-4 Results obtained by oxidation methods for fusain have been checked against results obtained from microscopic methods on duplicate samples of the same coals, but to the author's knowledge this has not been done for bright and dull coal components. For this reason it is not certain that the two methods of analysis identify essentially the same chemical or physical units. It would be highly desirable to see results of the application of both methods to duplicate samples, but in the absence of any such data the author has attacked the problem indirectly. From the U. S. Bureau of Mines samples were obtained of three Alabama coals which the USBM had analyzed optically and reported on over the past 30 years. These samples were subjected to analyses by oxidation rate methods. Results of this work, and comparisons with the USBM analyses, have been published. This was the first indirect approach to the problem. The present report attempts a second indirect approach by way of internal validation.

Jun 1, 1955