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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Theory and Experiments of Fiber Optic Temperature and Vibration Sensors

Stoute, Clyde 10 1900 (has links)
Fiber optic temperature and vibration sensors were designed and built to take readings in the harsh environment of a steel mill. The sensors are insensitive to electromagnetic noise; making them well suited for the use in such an environment. The temperature sensor uses an optical filter technique. A piece of intrinsic silicon is inserted between two optical fibers and 1064nm wavelength light is transmitted through the silicon. As the temperature increases, the silicon becomes more highly absorbing. The vibration sensor uses an optomechanical technique. Light is transmitted across a short air gap between two optical fibers. One of the fibers acts as cantilever while the other is fixed. As the cantilever vibrates, the transmitted power fluctuates, which enables the detection of the frequency and amplitude of the vibration. Sensors were initially tested under laboratory conditions, and subsequently field tested at ArcelorMittal Dofasco. The temperature sensor has a sensitivity of 0.4°C over the temperature range from 22°C to 120°C. The vibration sensor has a sensitivity of 2.87mV /g peak over a frequency range from 0 to 1250 Hz. / Thesis / Master of Applied Science (MASc)
2

Comportamento de íons e sua associação a resíduos de indústria siderúrgica em manguezal do sistema estuarino de Santos - Cubatão/SP / The behavior of ions and their association to the waste from steel mill in a fenland located in estuarine system of Santos - Cubatão/SP

Nascimento, Silvia Cremonez 30 November 2007 (has links)
O sistema estuarino de Santos, situado em Cubatão, representa um dos mais importantes exemplos brasileiros de degradação ambiental por poluição de origem industrial do país. Entre as atividades industriais geradoras de resíduos do estuário, destaca-se a indústria siderúrgica, de especial interesse nesse trabalho. O minério de ferro utilizado para a fabricação do aço é constituído essencialmente de hematita e no processo siderúrgico ele é fundido em altosfornos utilizando calcário como fundente e carvão mineral como redutor. Esse processo origina o ferro gusa tendo como impurezas carbono, silício, enxofre, fósforo, manganês etc. O ferro fundido assim obtido por meio do resfriamento desta mistura é muito quebradiço, não podendo ser utilizado, e a adição de alguns elementos como manganês, cobre e chumbo produzem aços com propriedades especiais e auxiliam na eliminação de impurezas. Os insumos utilizados nos processos siderúrgicos resultam em subprodutos que são diariamente descartados em área de manguezal que, como se sabe, são sistemas funcionalmente complexos, que se desenvolvem na zona de contato das águas marinha e fluvial. Esta área serviu para descarte de resíduos durante um período de aproximadamente 30 anos e somente a partir da década de 90 a CETESB exigiu a instalação do Aterro. Desta forma, não há possibilidade de se ter comportamento uniforme relacionado à disponibilidade iônica para o meio ambiente. Neste trabalho os dados analíticos indicaram baixa mobilidade iônica dos resíduos sólidos e que ocorrem de modo intermitente. Resultados de estudos experimentais em colunas de lixiviação, simulando água de chuva, e submetendo os resíduos à diferentes condições de força iônica, comparados com os fenômenos que ocorrem no meio natural, permitiram concluir que as águas pluviométricas têm menor influência e o fator decisivo para a disponibilidade iônica são pH e as variações dos níveis d´água em função das marés. / The estuarine system in Santos, located in Cubatão, is one of the most important Brazilian examples of environmental degradation caused by the pollution from Brazilians industries. Among the industries that dispose waste into the sewage, the steel mill stands out, and that is the reason why it the subject of this project. The iron ore used to produce the steel is a compound essentially of hematite and in its manufacture, it is casting in great temperature ovens by using calcareous to casting and coal to reduce. This process produces iron that is compound of impure carbon, silicon, sulphur, phosphorus, manganese and so on. The cast iron obtained by cooling this mixture has low resistance to break so it is no longer used, and the impurity are later removed by adding some elements as manganese, copper and lead and that produces steel with special properties. The incomes used in the manufacture of steel generates others products that are daily disposed in the fenland with no specific requires that, as known, are complex systems which develop in the contact area of the sea water and the fluvial one. In this land waste was disposed during 30 years and only after the 90´s, CETESB demanded the landfill project. So, there is no stable behavior of the availability of ions to the environment. The analytical data show low mobility of the ions and that it occurs in an intermittent way. The result from the experimental studies in a column that leached, which simulates the rain water moving through the waste in several conditions of ion strength, compared to the what happens in natural environment, concluded that the sea water and pH has lower influence and the reason for that is because the availability of ions are the variation of the water table according to tidal influence. It is proved that iron ions, manganese, copper, lead and zinc are constantly being freed which is a great hazard to the bioaccumulation once the fenland is one of the most productive ecosystems of the planet.
3

Comportamento de íons e sua associação a resíduos de indústria siderúrgica em manguezal do sistema estuarino de Santos - Cubatão/SP / The behavior of ions and their association to the waste from steel mill in a fenland located in estuarine system of Santos - Cubatão/SP

Silvia Cremonez Nascimento 30 November 2007 (has links)
O sistema estuarino de Santos, situado em Cubatão, representa um dos mais importantes exemplos brasileiros de degradação ambiental por poluição de origem industrial do país. Entre as atividades industriais geradoras de resíduos do estuário, destaca-se a indústria siderúrgica, de especial interesse nesse trabalho. O minério de ferro utilizado para a fabricação do aço é constituído essencialmente de hematita e no processo siderúrgico ele é fundido em altosfornos utilizando calcário como fundente e carvão mineral como redutor. Esse processo origina o ferro gusa tendo como impurezas carbono, silício, enxofre, fósforo, manganês etc. O ferro fundido assim obtido por meio do resfriamento desta mistura é muito quebradiço, não podendo ser utilizado, e a adição de alguns elementos como manganês, cobre e chumbo produzem aços com propriedades especiais e auxiliam na eliminação de impurezas. Os insumos utilizados nos processos siderúrgicos resultam em subprodutos que são diariamente descartados em área de manguezal que, como se sabe, são sistemas funcionalmente complexos, que se desenvolvem na zona de contato das águas marinha e fluvial. Esta área serviu para descarte de resíduos durante um período de aproximadamente 30 anos e somente a partir da década de 90 a CETESB exigiu a instalação do Aterro. Desta forma, não há possibilidade de se ter comportamento uniforme relacionado à disponibilidade iônica para o meio ambiente. Neste trabalho os dados analíticos indicaram baixa mobilidade iônica dos resíduos sólidos e que ocorrem de modo intermitente. Resultados de estudos experimentais em colunas de lixiviação, simulando água de chuva, e submetendo os resíduos à diferentes condições de força iônica, comparados com os fenômenos que ocorrem no meio natural, permitiram concluir que as águas pluviométricas têm menor influência e o fator decisivo para a disponibilidade iônica são pH e as variações dos níveis d´água em função das marés. / The estuarine system in Santos, located in Cubatão, is one of the most important Brazilian examples of environmental degradation caused by the pollution from Brazilians industries. Among the industries that dispose waste into the sewage, the steel mill stands out, and that is the reason why it the subject of this project. The iron ore used to produce the steel is a compound essentially of hematite and in its manufacture, it is casting in great temperature ovens by using calcareous to casting and coal to reduce. This process produces iron that is compound of impure carbon, silicon, sulphur, phosphorus, manganese and so on. The cast iron obtained by cooling this mixture has low resistance to break so it is no longer used, and the impurity are later removed by adding some elements as manganese, copper and lead and that produces steel with special properties. The incomes used in the manufacture of steel generates others products that are daily disposed in the fenland with no specific requires that, as known, are complex systems which develop in the contact area of the sea water and the fluvial one. In this land waste was disposed during 30 years and only after the 90´s, CETESB demanded the landfill project. So, there is no stable behavior of the availability of ions to the environment. The analytical data show low mobility of the ions and that it occurs in an intermittent way. The result from the experimental studies in a column that leached, which simulates the rain water moving through the waste in several conditions of ion strength, compared to the what happens in natural environment, concluded that the sea water and pH has lower influence and the reason for that is because the availability of ions are the variation of the water table according to tidal influence. It is proved that iron ions, manganese, copper, lead and zinc are constantly being freed which is a great hazard to the bioaccumulation once the fenland is one of the most productive ecosystems of the planet.
4

Energibalans av två glödgningsugnar inom ett integrerat stålverk

Färnström, Dennis January 2017 (has links)
Av den globala energianvändningen så upptar stålindustrin hela 5 % och sett till CO2 – utsläppen som orsakats av mänskliga faktorer så upptar stålindustrin hela 7 %. Stålindustrin är en energikrävande industri och därför är det viktigt att se över dess energianvändning för en nutida och framtida hållbarhet.  Ugnar är en av de bidragande faktorerna till den höga energianvändningen och de drivs på icke förnybara bränslen, därför är studier kring detta av hög relevans. Moderna tekniker gällande ugnar i dagens läge riktar sig mycket åt förbränningstekniken, d.v.s. förbränningen av bränslet som ugnarna drivs på. Oxyfuel-tekniken innebär att bränslet förbränns med ren syrgas istället för luft, vilket i huvudsakligt syfte är för att höja förbränningsverkningsgraden. Att använda brännare som kan återvinna rökgaser är också en modern teknik för energieffektiv ugnsdrift.  Outokumpu är ett världsledande företag inom tillverkningen av rostfritt stål och anläggningen i Avesta är ett integrerat verk, det betyder att ståltillverkningen i Avesta omfattar hela processen från råmaterial och skrot till färdig produkt. Anläggningen består av tre huvudsakliga verk som kallas stålverket, varmbandsverket och slutligen Linje 76 & Z-High vilket är avdelningen som dessa två glödgningsugnar befinner sig.  Det huvudsakliga syftet med denna rapport är att uppvisa en energibalans av två glödgningsugnar inom Outokumpus anläggning i Avesta, avgränsningarna är också tydliga då energibalansen drar sig ifrån den första ugnens inlopp till den andra ugnens utlopp. Och det är den termiska energieffektiviteten som har studerats, d.v.s. hur mycket energi man får ut av den olja som sätts in. Framtagandet av data har genomförts med hjälp av historiska data gällande ugnarnas drift under ett tidsspann på 3 månader tillbaka i tiden, även manuella temperaturmätningar har genomförts.  En verkningsgrad har tagits fram för varje ugn och ugnarna tillsammans, verkningsgraderna har beräknats genom att väga förhållandet mellan hur mycket energi som det glödgade materialet har tagit upp, med hur mycket olja som har använts under samma tidsspann.   De huvudsakliga resultaten till denna studie tyder sig på att ugnarna är effektiva till att värma stålet och har relativt små transmissionsförluster från ugnarnas omslutande areor. Däremot så finns potential att kunna återvinna mer värme ifrån rökgaser i avgaspannan. / The steel industry occupies the whole 7 % of the global carbon dioxide emissions caused by human factors and 5 % of the global energy usage. The steel industry is an energy intense industry and it’s therefore important to analyze its energy use for its future sustainability. Furnaces are driven on non-renewable fuels and are one of the devoting components to the high energy consumption, so studies of this are of high relevance.  Regarding modern techniques of furnaces in today’s mode are much concentrated on the combustion, which means the combustion of the fuel that supplies the furnaces with heat.  Oxy-fuel technology means that the fuel is combusted with pure oxygen instead of air, and its purpose is to increase the combustion efficiency. A second modern technology is the usage of burners that are able to recycle flue gases as an increase of energy efficiency.  Outokumpu is a world leading company in the manufacture of stainless steel and the plant in Avesta is an integrated steel mill, which means the steel production cover the entire process from scrap and raw material to finished product. The plant consists of three main works called the steel mill, hot rolling mill and KBR L76 which is the department for these annealing furnaces.  The main objective of this report is to present an energy balance of two annealing furnaces at the Outokumpu plant in Avesta. The boundary of the study is clear, the energy balance will take part from the inlet of the first furnace to the outlet of the second one. It’s the thermal energy efficiency that has been studied, that is to say how much energy you get from the fuel that is added. Information has been collected using historical data on the operation of the furnaces during a three month period of time, also manual temperature measurements has been carried out.  By calculations an efficiency has been developed for each furnace and the furnaces together. This has been carried out by weighing the proportion of the amount of heat that all material have accumulated, with the amount of oil used during the same time.  The results of this study mainly indicate that the furnaces are effective in heating the steel, and its heat losses from the surrounding areas are small. On the other hand, there is potential for recycling more heat regarding the use of flue gases in the exhaust-boiler.
5

Microsatellite DNA Mutations and Polycyclic Aromatic Hydrocarbon (PAH) Metabolites in Wild Double-crested Cormorants (Phalacrocorax auritus) from Hamilton Harbour Associated with Exposure to Airborne Pollutants

King, Laura E. 10 1900 (has links)
<p>Hamilton Harbour is one of the most polluted sites on the Great Lakes, affected by airborne and sedimentary contamination as a result of both heavy vehicle traffic and thousands of kilograms of industrial steel emissions. Polycyclic Aromatic Hydrocarbons (PAHs) are ubiquitous mutagenic byproducts of incomplete organic combustion; they are present at very high concentrations in the air and sediment of Hamilton Harbour. We quantified DNA mutation rates in three different nesting colonies of Double-crested Cormorants (<em>Phalacrocorax auritus</em>) using five microsatellite markers. These colonies were located at various distances from sources of PAHs and other contamination. We compared pollution-exposed and reference colonies, hypothesizing that cormorants living closest to pollution will have higher rates of germline microsatellite mutations than those living farther away from pollution sources. Using a pedigree approach, we identified mutations when chicks showed microsatellite alleles not found in either parent, and other explanations such as extra-pair parentage had been ruled out. Microsatellite mutation rates were 4.4 times higher at the Hamilton Harbour site closest to the industrial sources of PAH contamination than the other Hamilton Harbour site, and both were higher than the reference colony. Metabolites of the PAH benzo[a]pyrene in cormorant tissues from both Hamilton Harbour sites were identified by LC-MS/MS, demonstrating that cormorants in Hamilton Harbour are exposed to, and metabolizing, PAHs. Diet was not substantially different between the two Hamilton Harbour colonies when measured with regurgitated samples and fatty acid analysis. This suggests airborne pollution in Hamilton Harbour induced germline mutations in cormorants.</p> / Master of Science (MSc)
6

Otimização do sistema de distribuição de gases numa usina siderúrgica integrada

Pena, João Gustavo Coelho 06 November 2013 (has links)
Made available in DSpace on 2016-12-23T14:07:24Z (GMT). No. of bitstreams: 1 Raphael Mariano Macieira - Parte 1.pdf: 2082403 bytes, checksum: 0145a5a29417fe7c6d36a2a1417ff32b (MD5) Previous issue date: 2013-11-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The production process in an integrated steel mill produces gases, which can typically be used as fuel by the plant itself. However, managing the distribution of combustible gases is a complex activity, mainly because of the imbalances between production and consumption profiles of gases, the capacity and operational constraints of gas accumulators, and the constraints to energy use in power plants. The objective of this work is to use mixed integer linear programming (MILP) as a formulation for the problem distributing gases in the integrated steel mill, and to solve the formulated MILP making use of an algorithm that was developed using the Branch and Bound technique together with the Simplex method. Finally, the case studies confirm that the model is able to find an optimal solution for the proposed problem / Nos processos para produção de aço em uma usina siderúrgica integrada são produzidos gases que normalmente podem ser aproveitados como combustíveis pela própria planta. Entretanto, gerenciar a distribuição destes gases combustíveis é uma atividade complexa, principalmente por causa dos desequilíbrios entre os perfis de produção e consumo dos gases, das limitações de capacidade dos acumuladores de gases e suas restrições operacionais, além das restrições para aproveitamento energético nas centrais termoelétricas. O objetivo deste trabalho é usar a programação linear inteira mista (MILP) como uma formulação do problema da distribuição de gases na usina siderúrgica integrada; e, para solucionar a MILP usar um algoritmo que foi desenvolvido usando a técnica Branch and Bound em conjunto com o método Simplex. Por fim, estudos de casos confirmam que o modelo é capaz de encontrar uma solução ótima para o problema formulado
7

On Constructing 'Our Home': North Korean Cinema and Symbolism

Cherry, Makayla 09 August 2022 (has links)
No description available.

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