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By Jorge Alberto Soares Tenório, Romano Espinosa, Felipe Fardin Grillo, José Roberto de Oliveira, Denise Crocce

"The aim of this work was evaluation of the recovery of Zn and Fe of the EAFD added to the hot metal in the form of briquette at temperature of 1500°C. The EAFD was agglomerated by cold briquetting and introduced in the hot metal. This study utilized a bench-scale equipment to melt, during this process to kept a flow rate of inert gas above the bath. Were collected periodically metal samples and the samples were analyzed for determination of the content of total silicon and carbon by chemical analysis. Zinc oxide, zinc ferrite and other oxides were reduced and were volatized and collected by a cleaning system of dust (baghouse) located on top of the oven. More than 98% of iron were recovered from EAFD during the test. It was possible to produce a dust containing about 68% zinc by means of adding of EAFD.IntroductionIn the first semester of 2010, steel production was about 706 million tons, 27.9 % more than in the first half of 2009. Not a significantly increase if 2010 data is compared with the first semester of 2007 (only 7.2 % higher), before the world’s economic crises. Steel production is divided into two main routes. The first one, and most used, is the Basic Oxygen Furnace Process (BOF process), which in 2008 accounted for approximately 67.1 % of steel production. The second route is carried out in the Electric Arc Furnace (EAF) that in 2008 represented 30.6 % [1 ].Electric arc furnace dust (EAFD) is a solid waste generated during the steel making process. It is classi?ed according to NBR 10004 as dangerous solid waste-class I, because the elements Pb e Cd leach in water exceeding the maximum limits permitted by the NBR 10004 [2 ]."

Jan 1, 2012

Additional Attractive Force Between Alumina Particles Due to Low Solubility of Dicarboxylic Acids

Sep 13, 2010

By André Vervoort

After the systematic closure of Europe’s coalfields in the late twentieth century, the emphasis is now clearly on industry’s environmental legacy. One aspect of the latter is the longterm surface movement above abandoned coal mines. The analysis of satellite data shows that the subsidence lasts longer than generally assumed. However, a few years after the flooding of the abandoned underground coal mines, a new phenomenon was observed, i.e., the direction of the surface movement was reversed. The phase of upsidence has already lasted for several decades, and only future measurements will tell how long it continues. A key conclusion is that the regions with maximum subsidence do not necessarily correspond to the greatest upsidence. In other words, buildings and infrastructure are subjected to a different loading from this upsidence than during the subsidence phase. The longterm surface movements have an impact on vulnerable structures in the densely populated regions of the former deep coal mining areas in Europe. These movements create additional damage. This new knowledge is also relevant for mines that are still in operation or future mines that are planned.

Feb 1, 2024

By C. K. Leith

(San Francisco Meeting, September, 1915) IN 1911, we published in the Transactions a brief account of the lateritic alterations of serpentine in eastern Cuba, producing the important iron-ore deposits of the Mayari and Moa districts.1 The special feature of that article was a quantitative treatment of the alterations, based on analyses, to show just what had happened in terms of chemical, mineralogical, and physical changes. Professor Kemp has published an interesting account of these ores, containing additional quantitative observations of his own, tending essentially to confirm the nature of the changes that bad been worked out.2 His discussion suggests to us the desirability of publishing certain additional quantitative data which were not included in our previous article. This seems especially desirable because quantitative measurements of lateritic alterations are rare, and this particular case may be regarded as typical of a fairly wide range of alterations of this kind. At the time of our examination of Mayari and Moa, deposits 29 complete analyses were supplied us by the chemists of the Spanish-American Iron Co., representing a graded series from the unaltered serpentine rock below to the ore at the surface. These analyses are given in the accompanying table. The mineralogical composition of the ores and rocks is comparatively simple and can be easily calculated from the analyses. In Fig. 1 the mineralogical changes from the serpentine rock below to the lateritic iron ore above, based on the analyses, are expressed in terms of weight, assuming alumina to have remained constant during the alteration. It is not easy by mere inspection of this table of analyses to determine what the progressive chemical changes have been in development of the ore. In order to bring this out clearly, the analyses have been graphically represented in Fig. 2 in such a fashion as to show the progressive additions and losses of substances during alteration.

Jan 7, 1915

(The following list contains the names of those members of the Institute of whose connection with military service we have only recently become acquainted; it also includes the names of a few who have recently been promoted or transferred, indicated by a *. A complete list was published in the Year Book, issued as a supplement of the Bulletin for March, 1915.) ADAMS, ARTHUR K., Lieut., Co. 2, E. 0. T. S., Camp Humphreys, Va. AMIDON, CLAUDE E., 11th Training Co., Casual Camp, Camp Cody, N. M *BARBOUR, P. E., Capt., Engineer Corps, U. S. A. *BENHAM, W. M., Master Engr., Headquarters Dept., 115th Engrs. A. E. F., Care Postmaster, N. Y. BICKNELL, H. L., Pvt., Co. D, 27th Engrs., Camp Leach, D. C. *BLANDY, S. H. B., Lieut., Royal Horse Artillery, B. E. F.

Jan 10, 1918

(The following list contains the names of those members of the Institute of whose connection with military service we have only recently become acquainted; it also includes the names of a few who have recently been promoted or transferred, indicated by a *. A complete list was published in the Year Book, issued as a supplement of the Bulletin for March, 1918.) ANDERSON, AMIL A., Co. A, 309th Regiment Engineers, 84th Div., American E. F., Care Postmaster, New York. ARMSTRONG, HAROLD K., Pilot, Naval Aviation, U. S. Naval Air Station, Miami, Fla. BASSETT, ARTHUR F., Co. 6, -E. 0. T. S., Camp Humphreys, Va. BEDDALL, THOMAS H., Adjutant, 1st Battalion, 1st Gas Regiment, American E. F. BERNARD, CLINTON P., Candidate, 12th Observation Battery, F. A. C. 0. T. S., Camp Taylor, Ky. BROOKE, LIONEL, 50th Co., 13th Battalion, 5th Replacement Engineers, Camp Gordon, Ga. BROWNING, EDWARD, Corp., 1st Regiment Engineers, Co. D, American E. F. BUGBEE, EDWARD E., S. A. T. C. Headquarters, Raleigh N. C. BUTTERFIELD, G. BRUCE, CO. C, 605th Engineers, American E. F. CADOT, J. J., 1st Lieut., U. S. Air Service, American E. F., Care Post- master, New York. CARLOCK, J. B., Major, 2d Battalion, 1st Gas Regiment, American E. F., France.

Jan 12, 1918

(The following-list contains the names of those members of the Institute of whose connection with military service we have only recently. become acquainted.) ADAIR, ARTHUR C., Corporal, 4th Co., 1st Tr. Bn., 154th D. B., Camp Meade, Md. BATCHELOR, STILLMAN, 1st Lieut., Co. 6, E. 0. T. S., Camp Humphreys, Va. BATES, BENNETT R., 1st Lieut., Engineers, Co. 3, E. 0. T. S., Camp Humphreys, Va. BJORGE, GUY N., Co. 3, E. 0. T. S., Camp Humphreys, Va. BOAS, Ross, H., U. S. A. BRADLEY, . H., JR., Capt., 408th Engineers, Camp Cody, N. M. BRINTON, OWEN F., Capt., Engineers, U. S. A. BROWN, HAROLD C., 2d Lieut., A. S. A.P.

Jan 1, 1919

By Shimi Tzobery, Jay Davenport, Raymond Henn, Sam Bandimere

Over the past several decades, the use of cement-based grouts using ultra fine cement as a replacement for portland cement has begun to gain acceptance as an alternative to chemical solution grouts used in permeation grouting. The amount of information currently available on grouts made with ultrafine cement is limited. The authors used a previously developed field testing program to perform additional tests to evaluate the permeation performance of portland and ultrafine cement-based grouts. For the first time, the 2003 testing program included an attempt to determine the 28 day compressive strength of the sand permeated by the grout.

Jan 1, 2005

By Phillip R. Mulligan, Catherine Johnson, Edward Kinzel, Cody Lough, Jason Ho

A shaped charge is an explosive device used to focus detonation energy in a desired direction. Shaped charges have numerous applications in several industries such as oil extraction, weaponry and demolition. The focusing of the detonation energy is the result of the Munroe Effect, which greatly increases the penetration properties of the explosive due to a void in the explosive’s volume. The void in the explosive is lined with a metal substrate that becomes a super-heated projectile when the explosive is detonated. Additive Manufacturing (AM) can allow greater design freedom and geometric complexity for the liner portion of the shaped charge. Specifically, hierarchical structuring and functional grading can potentially provide greater velocity, directionality, and efficiency. By utilizing AM, the conventional use of shaped charges can be greatly expanded upon and may open new possibilities. In this work, selective laser melting (SLM) was used to explore different conical shaped charge (CSC) liners made out of stainless steel 304L. A series of liners were tested that had varying densities and were compared to conventional liners. The CSCs were filled with the high explosive Composition C-4 and detonated to evaluate performance. The blast events were recorded using break wire screens to calculate the velocity of the jet through steel target plates over a standoff of 6 times the charge diameter. A high-speed camera recorded the blast event to calculate the velocity of the jet through the air. The depth of penetration into the steel target plates was also used as a measurement of the effectiveness of the CSCs. The aim of this work is to show the potential for advanced shaped charges produced using SLM.

Jan 1, 2019

By D. W. Collins

Several organic and inorganic substances are widely used to control deposit structure and morphology during the electroprocessing of copper. Methods for monitoring the levels of thiourea, glue and guar gum during electrorefining and electrowinning have been successfully developed under the trade names of Reatrol and CollaMat. Other instrumental methods have been developed for additives and decomposition products associated with the electroplating of copper and other metals. Generally, these methods have been found to be either insufficiently sensitive or lacking in the desired selectivity for some or all of the additives. These procedures have mostly employed DC techniques; i.e., cyclic voltammetry, Tafel analysis, etc. In this work, chronopotentiometry (CP) and AC voltammetry were used to examine the interaction of glue, guar gum, thiourea and chloride during the electroplating of copper onto a platinum electrode. In addition, the interactions between the additives have been explored. It was found that glue in pure electrolyte (H2S04 and CuS04 only) had no effect on the chronopotentiogram. Glue was only active if chloride ions were present. The addition of thiourea resulted in several different chronopotentiograms depending on the presence of either chloride or chloride and glue. Thiourea used in conjunction with glue and chloride showed a significant increase in the polarization during copper deposition when compared to the electrolyte containing only glue and chloride. The use of a modified channel electrode further increased the sensitivity of CP. The use of AC voltammetry was explored as a technique to monitor some of the additives. AC voltammograms have more spectral detail then their DC counterparts and it is possible to monitor some of the additives at very low concentrations with AC techniques.

Jan 1, 1999

By Caio Moreira, Saulo De Rezende, Nelly Ruíz

The present project sought alternatives for this material through the Mining Lab Beginnings program, which was developed by Nexa in partnership with Escalab to find solutions for the company's highly complex challenges. Through the program, several solutions were evaluated, with additives for the construction market being the most prominent. Tests were conducted to confirm the efficiency of jarosite in the mixture that composes this material. With successful laboratory tests, the technology was tested on an industrial scale, where it also demonstrated its technical and economic viability. The project is now moving into the operational phase, demonstrating that circular economy is the best solution for disposed tailings.

Sep 29, 2023

By Leandro Seixas Bicalho, Wagner Cláudio da Silva, Kelly Laranjeira Nunes, Lívia Marques Faustino

Seeking to implement the Global Industry Standard on Tailings Management to improve the safety of their tailings facilities across the globe, mining companies are motivated to invest in new technologies to recover valuable minerals from tailings. One solution being evaluated is the use of magnetic separators to concentrate ultrafine tailings. However, this approach is energy intensive as it requires high magnetic fields to recover ultrafines, and usually results in low mass yields. Additives that modify pulp rheology and surface properties, or selective flocculate ultrafine particles, were tested to enhance the performance of magnetic separation. Promising results in laboratory scale testing different types of additives confirmed that it is possible to increase the mass yield, keeping the selectivity of this stage.

Feb 1, 2024

By C. RAMADINI, F. NURJAMAN, A. SHOFI, B. SUHARNO

In this work, the selective reduction of lateritic nickel ore was carried out using sodium sulfate, sodium carbonate, and sodium chloride as additives. The 5 wt% of anthracite coal, which contains 60.35% of fixed carbon and 1.9% of sulfur, was used as a reductant. All raw materials were mixed homogenously prior to the pelletization process into 10–15 mm of diameter. The reduction process was carried out to 50 g of pellets at 950 °C, 1050 °C, and 1150 °C for 60 min in a muffle furnace at atmospheric pressure. It continued with a wet magnetic separation process to separate ferronickel (concentrates) and impurities (tailings). Iron and nickel grade analysis was performed using XRF, while phase transformation and microstructure were analyzed with XRD and SEM–EDS. The results showed that the sodium sulfate was superior, resulting in the highest nickel grade in concentrate, i.e., 15.06%. The sulfidation mechanism, which could inhibit the metallization of iron, effectively increased the nickel grade in concentrate than decomposition of carbonate and chloridization process. The sulfur content in the reductant also influenced the selective reduction process. It promotes more sulfidation of iron, thus increasing the nickel grade in concentrate.

Jul 7, 2021

By C. RAMADINI, F. NURJAMAN, A. SHOFI, B. SUHARNO

Nickel demand is increasing along with the rising need for stainless steel and other alloy steel/iron. The small addition of nickel in such materials can improve impact strength, ductility and corrosion resistance. Nickel is generally obtained from nickel sulfide ores (nickel associated with sulfur) and nickel laterite ores (nickel associated with iron and magnesium silicate). Almost 60 percent of nickel is now produced from sulfide ores, despite its existence in sulfide ores being less than in laterite ores. However, the depletion of sulfide ore reserves makes the mastery of nickel laterite ore processing of important and immediate concern. Selective reduction followed by magnetic separation has been in development in lateritic nickel ore processing to overcome the issues of high energy consumption and pollution associated with conventional pyrometallurgy methods such as blast furnace and rotary kiln electric arc furnace (RKEF).

By R. Das Gupta

Variations in the characteristics of bentonite, magnetic taconite concentrate and system water have been examined to show their effects on pelletizing. Chemical methods have been tried to alter the clay or the system water so as to obtain pellets with desired properties. Those methods include ion exchange and the use of supplemental binders (organic and inorganic).

Jan 1, 1978

By C. B. Huntress

"We have ourselves to blame in the steel industry for our condition." These words were addressed twelve days ago by James A. Farrell, President of the United States Steel Corporation, to his "comrades" at a meeting of the American Iron and Steel Institute. They carry a note of challenge to all industry, and particularly to the coal industry, where they point the way to the pressing need for operators everywhere to get their feet under one table. It is that note which I would stress to all producers. You have yourselves to blame for your condition. True, there are inter-district competition and competition of substitute fuels, but they'll always be with us, more or less, and the only sensible, sane course is to remove the evils within our respective districts, which can be done only by constructive effort along cooperative lines. It's the same story in Alabama, the same in Illinois and elsewhere. The larger number of the men gathered here are at the front, as it were, in the business of mining coal. They are the men who are doing a remarkable operating job. And naturally, the sessions of this annual meeting treat of news from the front, of technical problems. But, as in actual warfare, those at the front are often uninformed of developments in the rear. They keep on fighting without fully sensing the significance of a disaster at headquarters. You've played your eighteen holes today and evidenced the efficiency of your technique in the, production of coal. It is not amiss to take advantage of this moment, the nineteenth hole, to ponder over what it's all about. After all, what do improvements in the art of mining mean if business policies engulf you in red ink? To the extent that mechanization is a factor in increased overhead, which in turn increases the pressure to produce regardless of market demand, it only aggravates our troubles unless there is the controlling influence of coordinated effort.

Jan 1, 1931

By J. V. W. REYNDERS

NOT only is your toastmaster silver-tongued in his references 'to myself, but he is also quite in the habit of "saying it in silver." I have analyzed with some care his statistics of the world's silver production, which have been distributed here along with the menu, although frankly from the point of view of most of us, the distribution rather than the production of silver is of immediate concern. Unlike the performers by whom we have been entertained between courses, the rest of us on the program will have to do without costume or musical accompaniment, which as my friend Rains can testify puts an artist under severe strain. I am entitled by right of office and of precedent to receive your attention for ten minutes. The Governor, who appears on the program as a speaker; however, has asked me for five minutes of my time, and Senator Thomas has insinuated that he would appreciate one-half of the remainder, wherefore, I must ask your close attention to the very brief remarks that I am able to make under such restricted circumstances. To begin with, I want you to believe that I am approaching the task set by your toastmaster with misgivings. In looking over the Institute records relating to the Salt Lake City meeting of 1914 for some precedent as to what I ought to say, I found but one reference-and that of the following indefinite char¬acter-" and Friday night there was a hilarious banquet to 350 members and guests."

Jan 1, 1925

Dr H. J. van Eck (Honorary Life Member): "Mr President, I regard it as a signal honour that I was invited to address the South African Institute of Mining and Metallurgy on its 75th Anniversary. I also wish to add my congratulations and good wishes to the many you have already received on this memorable occasion. Seventy-five years is indeed a good age and the achievements of your Institute certainly justify this special celebration. South Africa owes her present prosperity largely to the technological ability and determination of her own people. Members of the Institute contributed in large measure to this great development of our country and through the years have upheld their high reputation for scientific integrity, dynamic enterprise and dedicated service. It was their knowledge which provided the key to unlocking the mineral wealth which lay dormant for countless ages. The history of world mining dates back many centuries. We know of the mercury mines of Spain, the tin mines of Cornwall and the zinc mines of Poland, but it was not until colonization of the western hemisphere started in about 1500 that mining of any consequence began in North America. It is true that the peoples of South America and Mexico had accumulated wealth out of gold and silver, but industrialized mining was not a feature of these agrarian cultures. The mining wealth that eventually developed in North America was based on advances in the technology of processing minerals and served as an incentive to people in other new countries. Big mines were opened elsewhere in the world. From Canada, Mexico, Venezuela, Brazil, Peru, Chile, Bolivia, Rhodesia, Australia, Burma and India, to name but a few, there has been a steadily increasing production of an expanding range of minerals and metals. By the middle of the 20th century the trend was to increase the production and use of such comparatively uncommon metals as cobalt, nickel, titanium, and others, and a great mining rush started to search for, and develop, the deposits of uranium, and related radio-active minerals. It is worth pausing a few minutes to reflect that most of early mining was based on the recovery of virgin metals like gold and silver or easily treated high grade ores of copper, tin and zinc. Today, much of this type of mining would be regarded as picking the eyes out of the mine. With the development of improved ore separating, ore concentration and recovery processes, we developed into bulk mining and bulk treatment and in South Africa we have some very big mines, also outside the gold mining industry at Phalaborwa, for instance. Mining techniques are applied which compare with the best in the world. These large mines could only develop because of the perfection of new concentrating techniques and, of course, because of the development of markets. We have mentioned nickel and cobalt. These names were given to those mischievous mining sprites called nickels and kobolds to whom the suspicious miners ascribed their inability to smelt copper from copper nickel or arsenious copper ores. In South Africa, the presence of minerals was known to the modern Western world as far back as 1497 when Vasco da Gama found the native 'strandlopers' at the St. Helena Bay wearing copper rings. In 1669, after the British East India Company had formed their settlement, they employed miners and assayers in prospecting for minerals and in 1685 found traces of copper in the copper mountain of Namaqualand where some 170 years later a rich deposit of copper was to be opened up. This deposit also had a chequered

My predecessor in the office of President of the Institute started a custom of visiting the various local sections, thus obtaining their points . of view and their ideas as to how the Institute can best serve the interests of its members. Exceedingly valuable- exchange of ideas was thus brought about. I am following this custom as far as the limited amount of free time at my disposal will allow me, and I trust that my successor in office will appreciate the benefit to be derived from following the custom thus initiated and will continue the swing around the circle of the local sections. The activities of the Institute are increased by the prestige gained from large numbers and I trust that every member of this local section will consider himself a member of the committee on increase of membership and will see if he is not able during the coming year to gain at least one new member for the Institute. This is a perfectly possible proposition for, although the membership of the Institute is at present approximately seven thousand, I feel sure there are at least seven thousand more men in the United States who are interested in mining, metallurgy or geology from the metal-mining point of view who would make admirable members or associate members of the Institute. The first consideration of the Institute as a body, and of each member as an individual, is to win the war and defeat the Huns. In order to accomplish this, the Institute, as a body, has cooperated with the other national engineering societies and the great bureaus of the Department of the Interior, the United States Geological Survey and the Bureau of Mines in forming committees to study and advise the Government on pressing problems of vital importance.

Jan 5, 1918

The Institute is at present in sound condition professionally and financially. During the past year 546 new members were elected, the total membership now numbering 5,221. The Treasurer's Report shows that the expenses of the Institute are met by its income. Your Directors have thought it wise to issue a referendum to the members asking for a vote upon the suggestion that the annual dues be raised from $10 to $12. This moderate increase is proposed not because the Institute needs it at present but to insure a continuation and increase in its activities and usefulness, and to provide a reserve fund for future emergencies. In well-conducted organizations, such as clubs, it is a wise and safe course to so adjust the clues of members that the total receipts from this source will about equal the annual expenditures, the initiation fees being used for reserve purposes. Our dues alone do not at present meet the expenses. This, I think, is the whole situation, so far as this question is concerned. Expenses might be reduced in some measure, but they cannot be materially reduced without affecting the integrity and usefulness of your Institute. Nothing of consequence in our internal affairs has occurred during the past year except, perhaps, the establishment of the Arizona Section and the prospect now assured of a Nevada Section. During recent months there has been a marked change in the relations of the Institute to its fellow societies and to the Government of the United States. That change is one of cooperation. The Secretary of the Navy has appointed two of your members to the Naval Consulting Board to cooperate with members of 10 other scientific organizations. This Board is now organized, and through its work your Institute is brought in close touch with the activities of the other societies and with the United States Navy. The President of the United States has requested us to recommend to the Government one of our representatives in each State in the Union to act in collaboration with a member in each State from the. American Society of Civil Engineers, the American Society of Mechanical Engineers, the American Institute of Electrical Engineers and the American Chemical Society, thus organizing a directorate of engineers for each State, that will conduct, through the members of each of the five societies referred to, living in each State, a campaign of industrial preparedness. No more important step than this, it seems to me,

Jan 3, 1916