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By Euzébio Bernabé Zanelato

A incorporação de resíduos proveniente de indústrias na construção civil é uma prática cada vez mais comum, pois além de diminuir a quantidade de material descartado no meio ambiente, pode ainda melhorar as propriedades dos materiais empregados na construção civil. A incorporação de resíduos em cerâmica já é realizada com sucesso em incorporações adequadas, inclusive em telhas onde a qualidade exigida pelo produto é superior. Dentre os resíduos com necessidade de destinação encontra-se o resíduo da indústria de papel. O objetivo deste trabalho é avaliar a incorporação do resíduo de papel na fabricação de telhas cerâmicas, foram utilizadas incorporações de 0%, 10%, 20% e 30% para comparação dos resultados. Os materiais utilizados na pesquisa, argila e o resíduo foram caracterizados pelos ensaios de granulometria, análise química e densidade real dos grãos. Para avaliar o melhor teor de incorporação foram confeccionados corpos de prova e realizados os ensaios de resistência à flexão, variação linear e absorção de água. Os resultados indicaram que é viável a utilização da incorporação de 10% de resíduo, apenas por questões econômicas e ambientais, já que as propriedades pouco se alteraram nesta incorporação.

Oct 30, 2017

By Frank S. Wartman

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Jan 1, 1927

By W. Geo. Waring

THE growing need of better methods for the recovery of zinc and other elements from complex sulfide ores has suggested an inquiry respecting a possible group separation of the elements by the aid of volatilization at more or less elevated temperatures. It 'is evident that if the zinc content of such ores can be completely separated, for instance, as pure oxide, by a volatilization 'method, there should be no difficulty in recovering the other elements by smelting and refining. Zinc burning" as applied to zinkiferous ores has advanced but little in practice since the invention of the wetherill grate-furnace process in 1852, as may be seen by reference to papers on the subject.' In other words the thermochemical reaction employed in effecting the volatilization of the zinc is essentially one of reduction by means of carbon, whether the ores treated contain their zinc in an oxidized form, or as the sulfide. The zinc vapors, liberated from the ores at a temperature above that required for the reduction of ZnO by C (about ,1100° C.) or for the volatilization of ZnS per se, (about' 1300°-1400° C.) are subsequently burned to ZnO or to ZnO + SOz, by contact with' atmospheric ,oxygen in the upper or posterior parts of the furnace chamber, or in a so-called "combustion chamber" after leaving the .furnace proper.

Jan 1, 1925

SOUTHERN CALIFORNIA LOCAL. SECTION Executive Committee SEELEY W. MUDD, Chairman C. COLCOCK JONES, Vice-Chairman FREDERICK J. H. MERRILL, Secretary-Treasurer, 631 Higgins Bldg., Los Angeles, Cal. RALPH ARNOLD A. B. CARPENTER In. order to make the meetings of the, Section more interesting and fruitful, the Executive Committee has formed a sub-committee on programs for. Section meetings, which announces for the coming autumn and winter season, four dinner meetings, at intervals of two months, in which the co-operation of all Section members is urgently. requested. The subjects chosen for discussion at these meetings, with the proposed dates, are as follows: Sept. 28, 1915. Mining Geology of Mojave County, Arizona. Dec. 14, 1915. General Geology and Mining Conditions in Southern California. Feb. 1, 1916. Petroleum, its Geology and Technology. April 4, 1916. General Mining Conditions in. South America. F. J. H.. MERRILL, Secretary.

Jan 10, 1915

By Morgan M. Sears, Gamal Rashed, Michael M. Murphy, Brent Slaker

A parametric study was conducted using FLAC3D numerical models to examine the impact of oblique loading on the strength and yield pattern of a stone pillar using two simplified geometry types. In type-1 the side walls of the pillars were assumed to be perpendicular to the roof and the floor, while in type-2 the side walls were assumed to be vertical. These two geometries are frequently used to simplify/model the creation of pillars in dipping mines. Results from the numerical modeling indicate that dipping pillars have reduced strength compared to horizontal pillars, and they are at an elevated risk of failure. Also, an asymmetric failure propagation pattern could be obtained depending on the interaction between the pillar width/height (W/H) ratio, seam dip, in situ stresses and pillar geometry.

By N. Arbiter

If two fluid phases are brought into contact with a solid, one fluid may completely wet the surface to the exclusion of the other, or both may wet it, forming a three-phase line of contact. These relative wetting tendencies are quantified by the contact angle 0 which is related by Young's equation (1,2) [12 cos? = 13 ? 23] [to the three interfacial tensions (3). No contact angle for the first fluid, indicating that it does not wet the solid in the presence of the second, means that the difference between the two solid-fluid fluid surface tensions, - 8 is greater than (or just 13 -23 equal to) the fluid-fluid tension 12; a finite angle indicates that the difference is less.*]

Jan 1, 1964

Diesel engines are used in underground mining 1 throughout the world. Exhaust gases from those engines contain toxic components. To protect quality in underground mines, diesel emission control was introduced decades ago, many years before the first surface applications. Today, emission controls, such as catalytic converters, are standard on underground diesel engines in countries concerned with occupational safety and health. Nett Technologies manufactures a range of diesel emission-control devices for underground mining. Emission problems are not the same at each mining operation. And there is no universal control technology. The selection of exhaust aftertreatment technology depends on raw exhaust emissions, particular emission problems, fuel quality and economics. Some of the technologies that have been used in underground mining to control diesel emissions include catalytic converters, diesel filters, fume diluters and water scrubbers. Table 1 compares the effectiveness of these technologies to control the particular components or aspects of diesel emissions.

Jan 1, 1997

SOUTHERN CALIFORNIA LOCAL SECTION Executive Committee SEELEY W. MUDD, Chairman C. COLCOCK JUNES, Vice-Chairman FREDERICK J. H. MERRILL, Secretary-Treasurer, 631. Higgins Bldg., Los Angeles, Cal. Ralph ARNOLD A. B. CARPENTER The Second Annual Meeting of the Southern California Local Section of the American Institute of Mining Engineers was held at 300 Germain Bldg. on June 18, 1915, at 8 P.M. Present were: Messrs. C. Colcock Jones, Carpenter; Merrill, Baumgarten, Staunton, Hodges, Holland, and Durell. In the absence of the Chairman; Mr. Jones presided. The tellers appointed to canvass the vote for Section officers reported 45 ballots cast. The following gentlemen were announced as duly elected to the several. . offices: Chairman, SEELEY W. MUDD, Vice-Chairman, C. COLCOCK JONES, Secretary-Treasurer, F. J. H. MERRILL, Members of Executive Committee, RALPH ARNOLD A. B. CARPENTER

Jan 8, 1915

By Alexandre Furtado Ferreira, Fernando Paulucio Quinelato

A solidificação tem papel fundamental nas propriedades finais do material, uma vez que parâmetros como temperatura, composição química e cinética influenciam diretamente na micro e macroestrutura resultante. A solidificação dos aços no lingotamento contínuo ocorre através do crescimento dendrítico em direção ao núcleo da placa. A velocidade de crescimento interfere diretamente sobre a formação da micro e macroestrutura, bem como na formação das dendritas. Tais efeitos influenciam o perfil de microssegregação e macrossegregação finais. O objetivo deste trabalho é avaliar o comportamento dos espaçamentos dendríticos secundários em função da temperatura de lingotamento e da macroestrutura resultante, além de calcular, através do uso de equações empíricas, a taxa de resfriamento local. Os resultados mostraram que para menores superaquecimentos os espaçamentos dendríticos secundários apresentam-se menores. Foi verificada uma elevada correlação entre espaçamento dendrítico secundário e posição ao longo da espessura da placa para o intervalo de superaquecimento de 22°C e 34°C. Com a utilização de uma equação empírica, foram obtidas curvas que mostram o comportamento da taxa de resfriamento local em função dos espaçamentos dendríticos secundários. Os resultados obtidos são importantes para subsidiar estudos futuros e propostas de otimização de processo relacionadas a micro e macrossegregação em placas de aço.

Oct 1, 2019

National Steel Shuts Weirton Coal Operation Dutch Firm May Aid Ungava Project

Jan 7, 1953

Committee of Arrangement E. P. MATHEWSON, Chairman. FRANK M. SMITH, Vice- Chairman D. C. BARD, Secretary, Montana State School of Mines, Butte, Mont. OSCAR ROHN, JAMES L. BRUCE. On Aug. 20, 1913, the following 30 members of the Institute residing in Montana made written application to the Board of Directors of the Institute for authority to establish a local section of the Institute to be called the Montana Section, with headquarters at Butte, and having such territory as may, later be determined on. This petition was granted by the Board at its meeting in Butte, Mont., Aug. 20, 1913. The committee named at the head of this paragraph was appointed to' arrange for permanent organization of this section.

Jan 9, 1913

MONTANA SECTION J. L. BRUCE, Chairman W. C. SIDERFIN, Vice-Chairman WALTER E. GABY, Secretary-Treasurer, 834 W. Granite St., Butte, Mont. N. B. BRALY W. T. BURNS A special meeting of the Directors of the Montana Section was held on July 24, 1916, with W. C. Siderfin, Vice-Chairman, presiding. The meeting was called for the purpose of electing a Secretary-Treasurer to fill the, vacancy created by the resignation of M. H. Gidel. Upon proper motions, the resignation of M. H. Gidel was, accepted, and Walter E. Gaby was elected to fill the office for the balance of the fiscal year. No further business was transacted, and upon motion the meeting adjourned WALTER E. GABY, Secretary.

Jan 9, 1916

By C. L. Kosmoski, B. M. Eiter, B. P. Connor

"In the recent past, the mining industry has witnessed a substantial increase in the numbers of fatalities occurring at metal and nonmetal mine sites, but it is unclear why this is occurring. One possible explanation is that workers struggle with identifying worksite hazards and accurately assessing the associated risk. The purpose of this research was to explore this possibility within the mining industry and to more fully understand stone, sand and gravel (SSG) mine workers’ thoughts, understandings and perceptions of worksite hazards and risks. Eight mine workers were interviewed and asked to identify common hazards they come across when doing their jobs and to then discuss their perceptions of the risks associated with those identified hazards. The results of this exploratory study indicate the importance of workers’ jobrelated experience as it applies to hazard identification and risk perception, particularly their knowledge of or familiarity with a task, whether or not they had personal control over that task, and the frequency with which they perform that task. IntroductionAccording to the U.S. Mine Safety and Health Administration (MSHA, 2015a), 37 mine workers were fatally injured in accidents at metal and nonmetal mine sites between October 2013 and January 2015, following a record low of 16 in 2012 and in 2011. In 2014 alone, 29 mine workers were fatally injured at a metal or nonmetal mine site, and 52 percent of these fatalities occurred at a surface stone, sand or gravel (SSG) mine. In January 2015, Joseph A. Main, Assistant Secretary of Labor for Mine Safety and Health wrote to stakeholders in the metal and nonmetal mining community and identified several areas where improvement was necessary to promote the health and safety of mine workers. One area identified was an increased focus on “daily and effective workplace exams to find and fix hazards” (MSHA, 2015b).Hazard detection is challenging in the mining industry, despite the existence of regulation. Mining is a major undertaking involving the use of complex heavy machinery, equipment and processes as well as numerous and diverse worker activities that take place in a dynamic, challenging environment (Scharf et al., 2001). In other industries that are similarly dynamic and unpredictable, such as the construction industry, a large proportion of hazards go undetected (Carter and Smith, 2006). It is critical that miners are able to both recognize worksite hazards and accurately assess the risk associated with the hazards, because their health and safety depend on their deciding whether and how to remove hazards and mitigate risks."

Nov 1, 2016

By Angel Rafael Arce Chilque

Este trabalho tem por objetivo estudar a relação da escória (coproduto da siderurgia) com a lama (rejeito da mineração de ferro), visando a utilização da mistura destes como insumo na construção civil particularmente na confecção de tijolos, mitigando impactos ambientais gerados pela extração de argila. O estudo envolveu a realização de ensaios de caracterização química e granulométrica da escória, lama e argila, compactação e modelagem da mistura, queima, absorção de água, cálculo de porosidade aparente e características geométricas dos tijolos confeccionados e determinação de resistência à compressão dos mesmos. Os resultados mostraram que não existe uma relação simples entre a resistência a compressão e a porosidade, indicando com isto que outros fatores devem ser considerados no controle da resistência à compressão.

Aug 8, 2018

MONTANA SECTION W. C. SIDERFIN, Chairman, OSCAR ROHN, Vice-Chairman, E. B. YOUNG, Secretary-Treasurer, 526, Hennesey Building, Butte, Mont. F. W. BACORN, C. D. DEMOND. The semi-annual meeting of the Montana Section was held at the Silver Bow Club, Butte, Montana, on Friday, Nov. 16, at 8 p. m.; this was a postponement of the regular October meeting because of conflict in date with the St. Louis meeting of the Institute. An informal dinner was served to 68 members and guests. After dinner, Chairman W. C. Siderfin called the meeting to order. The minutes of the annual meeting, of Feb. 2, 1917, and the special meeting of May 21, 1917, were read and approved. C. W. Goodale led the discussion with "Notes on the St. Louis Meeting." He was followed by J. H. Warner who spoke on " The Joplin and Miami Districts," and by J. L: Bruce, Alexander Leggatt, N. B. Braly, and E. B. Young, the latter speaking on the work of the War Minerals Committee; and on the Cosden Oil Refinery at West Tuba, Okla. R. H. Sales reviewed briefly the manganese situation. E. N. Norris presented a paper on "Fire Proofing of Mine Shafts by the Anaconda Copper Mining Co." This resulted in interesting discussion by C. L. Berrien, C. E. Nighman, N. B. Braly, W. B. Daly, B. H. Dunshee, and J. J. Carrigan. C. L. Berrien and C. E. Nighman presented their papers on "Fire Extinction by Hydraulic Filling." In view of the late hour, discussion was waived. The executive committee, by unanimous consent, decided to request written discussion of the above papers to be presented at the next meeting, in February. B. B. Thayer spoke interestingly on the work of the Naval Consulting Board, and referred to the arsenic situation. Spencer Miller, also a, member of the Naval Consulting Board, entertained the-meeting with a vivid description of the method of "Coaling Battleships at Sea." Robert Sticht of Tasmania, in a short talk, spoke feelingly of his relations with the United States. At a late hour adjournment ended a most successful and interesting meeting. E. B. YOUNG, Secretary.

Jan 1, 1918

COLUMBIA SECTION S. S. FOWLER, Chairman., J. C. HAAS, Vice-chairman, LYNDON K. ARMSTRONG, Secretary-Treasurer, 720 Peyton Bldg., Spokane, Wash. W. H. LINNEY. J. F. MCCARTHY. On July 15, 16, and 17, 1918, through the good offices of Secretary Stoughton, and the courtesy of War Department officials, Columbia Section was able to secure a series of moving pictures which were presented under the auspices of the Spokane Engineering and Technical Association.. The title was "The Way Out," representing the activities of individuals who had lost an arm, a leg, or both, yet whose apparent misfortunes were made the stepping stones to advancement in various human activities. The exhibitions were given at Natatorium Park in the evening, each of the three performances being attended by 1000 per-sons. Later the films were shipped to Kellogg, Idaho, where they were shown in the principal playhouse one evening to a full house. On July 31, 1918, the Columbia Section participated in the luncheon and other entertainment in honor of Alfred D. Flinn, Secretary of the Engineering Council, who made a trip through the country to meet different classes of engineers, members of the National Societies, for whom he had a message. The entertainment was under the auspices of the Spokane Engineering and Technical Association, Mr. Peter Mogensen presiding. The luncheon was held in the Elizabethan Room, Davenport Hotel, at noon, 35 engineers being present, of whom about one-third were our members.

Jan 9, 1918

By Daniel Asunción García Ramos

El presente texto señala la influencia del quebracho como agente tensoactivo que evita el problema causado por el azufre a través de concentrados, cuyas especies mineralógicas predominantes son: esfarelita, pirita, incrementándose la extracción de metales. En este sentido, este método hidrometalúrgico permite que los concentrados que tienen plomo y arsénico en su composición, sean neutralizados para neutralizarlos como sulfatos sólidos, mientras que los sulfuros de zinc y de cobre pasan a la solución acuosa en estado iónico para ser recuperados posteriormente por electrodeposición.

Dec 1, 2015

BOSTON LOCAL SECTION Executive Committee HENRY L. SMYTH, Chairman ALFRED C. LANE, Vice-Chairman AUGUSTUS H. EUSTIS, Secretary-Treasurer, 131 State St., Boston, Mass. ROBERT H. RICHARDS ALBERT SAUVEUR Meets on the first Monday evening of each winter month Twenty-fourth Meeting The Twenty-fourth meeting of the Boston Local Section was held at the Exeter Street Theater, Boston, Monday, Jan. 4, 1915. The Chairman, Henry L. Smyth, introduced Mr. S. Le Fevre, of Mineville, N. Y., who presented an exhibit of moving pictures, illustrating the various operations of mining and milling iron ore as carried out at Mineville. Mr. Le Fevre pointed out, as the pictures were run off, the dangers of the various operations, and the precautions that should be taken to avoid or minimize these dangers. . After the exhibition of pictures, the members adjourned to the University Club, where dinner was served. At the close of the dinner and an impromptu recital by Mr. Weeks, the meeting was adjourned. AUGUSTUS H. EUSTIS, Secretary.

Jan 2, 1915

Expect Labrador Iron Ore Shipments by 1954 Iron ore shipments from the Quebec-Labrador area are a "definite expectation" by late summer, 1954, according to William H. Durrell, general manager of the Iron Ore Company of Canada. About $120 million have been invested in the project, with a total of $200 million expected to be reached before a ton of ore is shipped, Mr. Durrell said. According to the general manager approximately 418 million tons of open pit highgrade ore have been proven in the project. Deposits lie several hundred miles north of the mouth of the St. Lawrence River in territory which was without transportation of any kind. Construction of a railroad from Seven Islands to Knob Lake, about 360 miles, is an important part of the development plan. The railroad will be the first to adopt complete roller bearing applications. Construction is on schedule with 215 miles of the route graded. Completion involves two tunnels through rock, one of almost half mile length, a 700-ft bridge and several smaller spans.

Jan 3, 1953

By E. Yigit

Hydrometallurgical production of zinc from concentrates is generally carried out by H2SO4 leaching. For the smooth operation of this process, some harmful components must be removed from the leach solution before the electrolysis stage; MgO is one of these compounds. Zinc concentrate samples from the Mount Isa mines were used in leaching tests. Leaching tests with an aqueous solution of H2SO4 and SO2 gas were carried out at various temperatures, pH levels and leaching durations. While duration and the pH value of the solution were effective parameters in H2SO4 leaching, temperature and pH were more effective in SO2 leaching for the removal of MgCO3 and CaCO3. Removal of MgCO3 and CaCO3 was generally achieved at low pH values. The results show that SO2 gas can be a good alternative to sulfuric acid in the leaching of MgCO3 and CaCO3

Jan 1, 2010