Dissertations / Theses: 'Industrial Furnace'

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Ellul, Connie. "Flameless Combustion for Industrial Furnace Heaters." Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505069.

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Carlborg, Hampus, and Henrik Iredahl. "Modeling and Temperature Control of an Industrial Furnace." Thesis, Linköpings universitet, Reglerteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-129617.

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A linear model of an annealing furnace is developed using a black-box system identification approach, and used when testing three different control strategies to improve temperature control. The purpose of the investigation was to see if it was possible to improve the temperature control while at the same time decrease the switching frequency of the burners. This will lead to a more efficient process as well as less maintenance, which has both economic and environmental benefits. The estimated model has been used to simulate the furnace with both the existing controller and possible new controllers such as a split range controller and a model predictive controller (MPC). A split range controller is a control strategy which can be used when more than one control signal affect the output signal, and the control signals have different range. The main advantage with MPC is that it can take limitations and constraints into account for the controlled process, and with the use of integer programming, explicitly account for the discrete switching behavior of the burners. In simulation both new controllers succeed in decreasing the switching and the MPC also improved the temperature control. This suggest that the control of the furnace can be improved by implementing one of the evaluated controllers.

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Hixson, Scott. "Rapid industrial furnace thermal modeling for improved fuel efficiency." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/5091.

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Thesis (M.S.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 9, 2009) Includes bibliographical references.

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Middleton, Kenneth George. "The failure of graphite arc-furnace electrodes." Thesis, Durham University, 1985. http://etheses.dur.ac.uk/7050/.

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Graphite electrodes used in steelmaking are joined together by threaded, tapered connectors (nipples) of similar material. The jointed regions are subjected to arduous thermal and mechanical stresses during use. Mechanical stresses arise from electrode self-weight and tightening torque, and the thermal stresses from the high furnace operating temperatures which ensure a high radiative surface cooling rate as the electrode is removed from the furnace. This thermal shock effect is thought to contribute to particular types of electrode failure. In this computer-aided analysis of the stresses induced by the above effects, a commercial finite element program is used in conjunction with a purpose-written finite difference program. Mechanical loads due to electrode self-weight and pretightening torque are evaluated and applied with suitable restraints to an axisymmetric finite element mesh, to obtain a mechanical stress analysis. The finite difference program is then used to calculate the time-variant temperature field experienced by an electrode on being removed from the furnace. An interpolation program is used to assign temperatures at the nodes of the same finite element mesh, the thermal stresses then being evaluated by the commercial finite element program. A 'failure envelope' analysis of the results identifies the critically-stressed regions of the joint and shows that in some such areas the thermal-shock stresses act to relieve the mechanically-induced stresses. A statistical analysis based on Weibull theory predicts a high incidence of crack formation due to thermal stresses. Finally, consideration is given to the effect of thermal orthotropy and temperature-dependent material properties.

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Correia, Sara Alexandra Chanoca. "Development of improved mathematical models for the design and control of gas-fired furnaces." Thesis, University of South Wales, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369080.

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Blanden, Zachary F. "Process development for high powered amplifier Au/Sn eutectic die attach via vacuum furnace." Thesis, State University of New York at Binghamton, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10250174.

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This research was conducted to develop and qualify a vacuum GaAs semiconductor monolithic microwave integrated circuit die attach process. Research was done to understand the causes and effects of voiding levels on device performance and reliability. Simultaneous investigation was done to qualify vacuum-attach as a successful methodology by which minimal voiding levels were achieved. After an initial vacuum-attach trial was completed to verify the methodology, internal accept/reject criteria were developed to qualify die attach interfaces. A dual phase attachment methodology was created to minimize tolerance stacking resulting in more consistent component placement. MATLAB image processing code was developed to quantify the voiding levels against the accept/reject criteria. Statistical methodologies were employed to troubleshoot root causes for special cause variation of initial attachment failures. A design of experiment was conducted testing three factors each at two levels (process gas [Gas A, Gas B], leaking chamber [yes, no], and carrier supplier [Supplier A, Supplier B]). The DOE identified process gas and its interaction with the carrier supplier to be significant. Further investigation of the carriers identified plating contamination, resulting in the process gas the primary factor of interest. A secondary experiment focusing on process gas identified no statistical difference between Gas A? and Gas B (Gas A? indicating a high purity form of Gas A). With this information, Gas A? was selected as the process gas. A total of 56 attachment interfaces were then produced yielding 0.7485% voiding, on average, following a Weibull distribution (?= 1.04171, ? = 0.75967) with zero rejections. The process?s consistency of minimal voiding levels were deemed a success and the process was released to production.

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Hougen, Krysta E. "Long-term Effects of Industrial History on the Forest Flora of Southeastern Ohio." Ohio University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1237857409.

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Borges, Cláudio Neves. "Modelagem matemática do processo industrial de coqueamento retardado." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-29062016-162519/.

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A unidade de coqueamento retardado é um processo térmico de conversão, utilizado pelas refinarias, para converter cargas residuais em produtos de baixo peso molecular e com alto valor agregado (gases, nafta e gasóleo) e coque verde de petróleo. Um pequeno aumento no rendimento líquido da unidade de coqueamento retardado proporciona benefícios económicos consideráveis, especialmente no destilado líquido. A concorrência no mercado, as restrições sobre as especificações do produto e gargalos operacionais exigem um melhor planejamento da produção. Portanto, o desenvolvimento de novas estratégias e modelos matemáticos, focados em melhores condições de operação do processo industrial e formulações de produtos, é essencial para alcançar melhores rendimentos e um acompanhamento mais preciso da qualidade do produto. Este trabalho tem como objetivo o desenvolvimento de modelo matemático do conjunto forno-reator do processo de coqueamento, a partir de informações obtidas em uma planta industrial. O modelo proposto é baseado na caracterização da carga e dos produtos em pseudocomponentes, modelos cinéticos de grupos e condições de equilíbrio liquido-vapor. Além disso, são discutidos os principais desafios para o desenvolver o modelo matemático do forno e do reator, bem como a caracterização rigorosa do resíduo de vácuo e dos produtos para determinar os parâmetros que afetam a morfologia do coque e a zona de reação no interior do reator de coque.
The delayed coke unit is a thermal conversion process, used by the crude oil refineries, to convert residual feedstocks into products of low molecular weight and high aggregated value (gases, naphtha and gasoil) and green coke. A small increase in the net yield in the delayed coke unit results in considerable economic benefits, particularly in the liquid distillates. The market competition, the restrictions on the product specifications and the operational bottlenecks require a better production planning. Therefore, the development of new strategies and mathematical models, focused in better industrial process operating conditions and product formulations, is essential to achieve better yields and a more precise product quality monitoring. The objective of this work is the development of a furnace-reactor mathematical model of the delayed coke process based on industrial plant information. The proposed model is based on the feed and product characterization as pseudo components, group kinetical models and liquid-vapor equilibrium. Furthermore, the main challenges to develop the furnace and reactor mathematical model are discussed, as well as the vacuum residual and the coke unit products rigorous characterization to determine the parameters that impact the coke morphology and the reaction zone inside the coke reactor.

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Stadler, Johan George. "Multi-objective optimisation using the cross-entropy method in CO gas management at a South African ilmenite smelter." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71631.

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Thesis (MScEng)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: In a minerals processing environment, stable production processes, cost minimisation and energy efficiency are key to operational excellence, safety and profitability. At an ilmenite smelter, typically found in the heavy minerals industry, it is no different. Management of an ilmenite smelting process is a complex, multi-variable challenge with high costs and safety risks at stake. A by-product of ilmenite smelting is superheated carbon monoxide (CO) gas, or furnace off-gas. This gas is inflammable and extremely poisonous to humans. At the same time the gas is a potential energy source for various on-site heating applications. Re-using furnace off-gas can increase the energy efficiency of the energy intensive smelting process and can save on the cost of procuring other gas for heating purposes. In this research project, the management of CO gas from the Tronox KZN Sands ilmenite smelter in South Africa was studied with the aim of optimising the current utilisation of the gas. In the absence of any buffer capacity in the form of a pressure vessel, the stability of the available CO gas is directly dependent on the stability of the furnaces. The CO gas has been identified as a partial replacement for methane gas which is currently purchased for drying and heating of feed material and pre-heating of certain smelter equipment. With no buffer capacity between the furnaces and the gas consuming plants, a dynamic prioritisation approach had to be found if the CO was to replace the methane. The dynamics of this supply-demand problem, which has been termed the “CO gas problem”, needed to be studied. A discrete-event simulation model was developed to match the variable supply of CO gas to the variable demand for gas over time – the demand being a function of the availability of the plants requesting the gas, and the feed rates and types of feed material processed at those plants. The problem was formulated as a multi-objective optimisation problem with the two main, conflicting objectives, identified as: 1) the average production time lost per plant per day due to CO-methane switchovers; and 2) the average monthly saving on methane gas costs due to lower consumption thereof. A metaheuristic, namely multi-objective optimisation using the cross-entropy method, or MOO CEM, was applied as optimisation algorithm to solve the CO gas problem. The performance of the MOO CEM algorithm was compared with that of a recognised benchmark algorithm for multi-objective optimisation, the NSGA II, when both were applied to the CO gas problem. The background of multi-objective optimisation, metaheuristics and the usage of furnace off-gas, particularly CO gas, were investigated in the literature review. The simulation model was then developed and the optimisation algorithm applied. The research aimed to comment on the merit of the MOO CEM algorithm for solving the dynamic, stochastic CO gas problem and on the algorithm’s performance compared to the benchmark algorithm. The results served as a basis for recommendations to Tronox KZN Sands in order to implement a project to optimise usage and management of the CO gas.
AFRIKAANSE OPSOMMING: In mineraalprosessering is stabiele produksieprosesse, kostebeperking en energie-effektiwiteit sleuteldrywers tot bedryfsprestasie, veiligheid en wins. ‘n Ilmenietsmelter, tipies aangetref in swaarmineraleprosessering, is geen uitsondering nie. Die bestuur van ‘n ilmenietsmelter is ‘n komplekse, multi-doelwit uitdaging waar hoë kostes en veiligheidsrisiko’s ter sprake is. ‘n Neweproduk van die ilmenietsmeltproses is superverhitte koolstofmonoksiedgas (CO gas). Hierdie gas is ontvlambaar en uiters giftig vir die mens. Terselfdertyd kan hierdie gas benut word as energiebron vir allerlei verhittingstoepassings. Die herbenutting van CO gas vanaf die smelter kan die energie-effektiwiteit van die energie-intensiewe smeltproses verhoog en kan verder kostes bespaar op die aankoop van ‘n ander gas vir verhittingsdoeleindes. In hierdie navorsingsprojek is die bestuur van die CO gasstroom wat deur die ilmenietsmelter van Tronox KZN Sands in Suid-Afrika geproduseer word, ondersoek met die doel om die huidige benuttingsvlak daarvan te verbeter. Weens die afwesigheid van enige bufferkapasiteit in die vorm van ‘n drukbestande tenk, is die stabiliteit van CO gas beskikbaar vir hergebruik direk afhanklik van die stabiliteit van die twee hoogoonde wat die gas produseer. Die CO gas kan gedeeltelik metaangas, wat tans aangekoop word vir die droog en verhitting van voermateriaal en vir die voorverhitting van sekere smeltertoerusting, vervang. Met geen bufferkapasiteit tussen die hoogoonde en die aanlegte waar die gas verbruik word nie, was die ondersoek van ‘n dinamiese prioritiseringsbenadering nodig om te kon vasstel of die CO die metaangas kon vervang. Die dinamika van hierdie vraag-aanbod probleem, getiteld die “CO gasprobleem”, moes bestudeer word. ‘n Diskrete-element simulasiemodel is ontwikkel as probleemoplossingshulpmiddel om die vraag-aanbodproses te modelleer en die prioritiseringsbenadering te ondersoek. Die doel van die model was om oor tyd die veranderlike hoeveelhede van geproduseerde CO teenoor die veranderlike gasaanvraag te vergelyk. Die vlak van gasaanvraag is afhanklik van die beskikbaarheidsvlak van die aanlegte waar die gas verbruik word, sowel as die voertempo’s en tipes voermateriaal in laasgenoemde aanlegte. Die probleem is geformuleer as ‘n multi-doelwit optimeringsprobleem met twee hoof, teenstrydige doelwitte: 1) die gemiddelde verlies aan produksietyd per aanleg per dag weens oorgeskakelings tussen CO en metaangas; 2) die gemiddelde maandelikse besparing op metaangaskoste weens laer verbruik van dié gas. ‘n Metaheuristiek, genaamd MOO CEM (multi-objective optimisation using the cross-entropy method), is ingespan as optimeringsalgoritme om die CO gasprobleem op te los. Die prestasie van die MOO CEM algoritme is vergelyk met dié van ‘n algemeen aanvaarde riglynalgoritme, die NSGA II, met beide toepas op die CO gasprobleem. The agtergrond van multi-doelwit optimering, metaheuristieke en die benutting van hoogoond af-gas, spesifiek CO gas, is ondersoek in die literatuurstudie. Die simulasiemodel is daarna ontwikkel en die optimeringsalgoritme is toegepas.

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Suopajärvi, H. (Hannu). "Bioreducer use in blast furnace ironmaking in Finland:techno-economic assessment and CO₂ emission reduction potential." Doctoral thesis, Oulun yliopisto, 2015. http://urn.fi/urn:isbn:9789526207063.

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Abstract Most of the steel produced in the world is based on the integrated blast furnace-converter route, which is based on the use of virgin raw materials. Large amounts of fossil-based, carbon containing reductants are used in blast furnaces, which results in carbon dioxide emissions into the atmosphere. Fossil carbon dioxide emissions from steel production can be reduced by new technologies or moving from non-renewable to renewable energy sources. Biomass-based reductants could be one way to reduce the specific emissions from blast furnace-based steel production. The aim of this thesis was to examine the techno-economic and CO₂ mitigation potentials of using bioreducers in blast furnace ironmaking. Bioreducer feasibility was analyzed in the Finnish context, but the research methods used can be applied more widely. The metallurgical properties of bioreducers were evaluated and compared to fossil-based reductants. The impact of bioreducers on blast furnace behavior and on other steel plant processes was evaluated, with an emphasis on the reductions achieved in CO₂ emissions at the plant scale. The CO₂ emissions, energy consumption and production costs of bioreducers were evaluated, as was the availability of energy wood for bioreducer production. The results show that solid, liquid and gaseous bioreducers can be produced with thermochemical conversion technologies. However, their suitability for blast furnace use varies greatly. The highest substitution of fossil-based reductants in a blast furnace is achieved with charcoal injection. The carbon footprint of torrefied wood, charcoal and Bio-SNG is moderate compared to fossil-based reducing agents and their production is energetically feasible. The economic feasibility of bioreducers is currently weak in comparison to fossil-based reducing agents, but competitive when compared to other CO₂ emission reduction measures such as carbon capture and storage. The biomass availability assessment revealed that sufficient amount of energy wood could be available for bioreducer production in the areas where Finnish steel plants are situated. The feasibility of bioreducer production could be improved by producing a number of products from the biomass and taking advantage of the process of integration possibilities
Tiivistelmä Suurin osa maailmassa tuotetusta teräksestä valmistetaan integroidulla masuuni-konvertteri reitillä, joka perustuu neitseellisten raaka-aineiden käyttöön. Masuuniprosessissa käytetään suuri määrä fossiilisia, lähinnä hiilipohjaisia pelkistimiä, jotka aiheuttavat hiilidioksidipäästöjä ilmakehään. Fossiilisia hiilidioksidipäästöjä voidaan teräksenvalmistuksessa vähentää uusilla teknologioilla tai siirtymällä uusiutumattomista energialähteistä uusiutuviin. Biomassasta valmistetut pelkistimet voisivat olla yksi mahdollinen keino alentaa masuunipohjaisen teräksenvalmistuksen ominaispäästöjä. Tämän työn tavoitteena oli tarkastella biopelkistimien käytön teknistaloudellista potentiaalia masuunikäytössä ja aikaansaatavia hiilidioksidipäästövähenemiä eri systeemirajauksilla. Työssä keskityttiin tarkastelemaan biopelkistimien hyödynnettävyyttä lähinnä Suomen tasolla, vaikka käytetyt tutkimusmetodit ovat sovellettavissa myös laajemmin. Työssä arvioitiin biopelkistimien metallurgisia ominaisuuksia, niiden vaikutusta masuuniprosessiin ja laajemmin muihin terästehtaan prosesseihin, pääpainon ollessa saavutettavan CO₂ päästövähenemän tarkastelussa. Työssä tarkasteltiin biopelkistimien valmistuksen CO₂ päästöjä, energiankulutusta ja tuotantokustannuksia sekä energiapuun saatavuutta biopelkistimien tuotantoon. Tulokset osoittavat, että biomassasta voidaan valmistaa kiinteitä, nestemäisiä ja kaasumaisia pelkistimiä termokemiallisilla konversioteknologioilla, joiden soveltuvuus masuunikäyttöön vaihtelee suuresti. Masuuniprosessissa suurin fossiilisten pelkistimien korvaavuus saavutetaan käyttämällä puuhiili-injektiota. Torrefioidun puun, puuhiilen ja Bio-SNG:n hiilijalanjälki on varsin maltillinen verrattuna fossiilisiin pelkistimiin ja niiden tuotanto on energeettisesti järkevää. Biopelkistimien taloudellinen kannattavuus verrattuna fossiilisiin pelkistimiin on tällä hetkellä heikko, mutta kilpailukykyinen verrattuna muihin CO₂ päästöjen vähennyskeinoihin, kuten hiilidioksidin talteenottoon ja -varastointiin. Energiapuun saatavuus biopelkistimien valmistukseen on suurin alueilla, jotka sijaitsevat lähellä Suomen terästehtaita. Biopelkistimien tuotannon kannattavuutta voitaisiin parantaa tuottamalla useita tuotteita ja hyödyntämällä prosessi-integraatiota

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Hrnko, Lukáš. "Návrh koncového efektoru pro manipulaci se skleněnou zátkou." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231136.

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The diploma thesis deals with the structural design of the end effector for handling with the glass stopper of the hydrogen reactor of high temperature semiconductor diffusion furnace. The work includes the summary of information about semiconductor diffusion furnace, the choice of the appropriate industrial robot, the design of the end effector structural solution, the design of its supporting structure, the power and strength calculation, the design of the end effector control and economic evaluation of its production. The 3D model together with 2D production documentation which contains the assembly drawing of the individual parts of end effector was created on the basis of the end effector design.

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Diaz, Mateus Fabian Andrey. "Desenvolvimento de modelo computacional para craqueamento termico." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266222.

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Orientador: Rubens Maciel Filho
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
Made available in DSpace on 2018-08-11T05:06:17Z (GMT). No. of bitstreams: 1 DiazMateus_FabianAndrey_M.pdf: 2380896 bytes, checksum: be3b7c2cb01810009ddbc674d0b696e6 (MD5) Previous issue date: 2008
Resumo: Neste trabalho é desenvolvida a modelagem matemática e a simulação computacional de um forno para processos de conversão térmica de frações pesadas de petróleo. O modelo cinético das reações de conversão é tomada de Sugaya (1993) a qual consta de uma reação irreversível de primeira ordem com 9 lumps reacionais e 24 pseudocomponentes. Os 24 pseudocomponentes são caracterizados e suas propriedades são calculadas mediante diferentes correlações e métodos encontrados na literatura. À medida que a carga avança pela tubulação do forno, a reação ocorre gerando quantidades maiores de componentes leves alterando as condições de fluxo como decorrência de alterações físico-químicas. Estes efeitos são levados em consideração na modelagem desenvolvida. O estado da mistura é verificado para cada passo de integração mediante a equação Soave Redlich Kwong. No caso de escoamento bifásico, as propriedades do líquido e do vapor são calculadas para determinar o regime de escoamento e calcular o Holdup. Este parâmetro permite estimar as propriedades de transporte, os coeficientes de transferência e a perda de carga. Inicialmente é simulada uma unidade piloto de craqueamento térmico. Esta unidade consta de uma serpentina aquecida isotermicamente, fato pelo qual só balanço de massa é integrado. O programa encontra as constantes cinéticas mediante um algoritmo Newton ¿ Raphson, cuja função objetivo é a diferença entre a conversão calculada e a conversão medida. Finalmente o forno industrial é simulado. Balanços de massa, momento, energia e temperatura de parede são integrados. Os resultados obtidos apresentam boa concordância com os dados do forno 23H ¿ 1 (Refinaria Presidente Bernardes, Cubatão) para craqueamento térmico. Deposição de coque na tubulação é avaliada para analisar o comportamento do processo. O programa desenvolvido permite o estudo do processo de craqueamento térmico para processos de conversão térmica como o coqueamento retardado e visco-redução. Novos parâmetros operacionais podem ser estudados, diferentes cargas e estratégias de controle podem ser simuladas e avaliadas com o software desenvolvido
Abstract: The mathematical modeling and the computational simulation of a process furnace for thermal conversion of heavy oil fractions is developed in this work. Kinetics of conversion reactions is from Sugaya (1993). It is based in a first order irreversible reaction with 9 lumps and 24 pseudocomponents. The 24 pseudocomponents are characterized and their properties calculated by different correlations and methods available in the literature. As walks through the furnace tubes, the feed, initially liquid, reacts generating light fractions and gas. The state of the mixture is checked for each integration step by a subroutine based on the Soave Redlich Kwong equation. When two phases are flowing, properties of the liquid and vapor are calculated to determine the flow regime and the holdup. This parameter allows to calculate the transport properties and the heat transfer and pressure drop coefficients. Initially, a thermal cracking pilot plant is simulated. This unit is formed by a reactor coil that is isothermally quenched; consequently, only mass balance is integrated. The program finds the kinetic constants by a Newton ¿ Raphson algorithm whose objective function is the difference between the calculated and measured conversion. Finally, an industrial furnace is simulated. Mass, momentum, wall temperature and energy balances are integrated. Results show good agreement whit the data reported from the industrial furnace 23-H-1 (Refinery Presidente Bernardes, Cubatão) for thermal cracking. Coke deposition in tubes is tested to analyze the performance of the process. The program developed in this work allows an insight study of thermal cracking processes such as delayed coking and visbreaking. New operational parameters, different feeds, control strategies and many other parameters can be studied.
Mestrado
Desenvolvimento de Processos Químicos
Mestre em Engenharia Química

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Runtti, H. (Hanna). "Utilisation of industrial by-products in water treatment:carbon-and silicate-based materials as adsorbents for metals and sulphate removal." Doctoral thesis, Oulun yliopisto, 2016. http://urn.fi/urn:isbn:9789526212630.

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Abstract Pollutant (such as metals and sulphate) contamination exists in the wastewaters of many industries, including mining operations, metal plating facilities, and tanneries. Adsorption is one of the most commonly used processes for the removal of pollutants from waters and wastewaters due to its high efficiency and simple operation. Activated carbon is the most frequently used adsorbent material, although its high cost inhibits its widespread use in wastewater treatment. Therefore, there is a need to develop other adsorbents from alternative inexpensive raw materials such as locally available industrial and mineral waste and by-products. The aim of this thesis was to study the possibility of using industrial waste materials such as carbon residue, metakaolin, blast-furnace slag and analcime as an inexpensive sorbent for iron, copper, nickel, arsenic, antimony and sulphate removal from aqueous solutions. To enhance their adsorption capacity, different chemical treatments (i.e. activation, modification, geopolymerisation) were performed. As a result, the level of removal of iron, copper and nickel by carbon residue and zinc chloride activated carbon residue was higher than that by the commercial activated carbon. Iron chloride modified carbon residue was the most effective sorbent material for sulphate removal when compared to the other studied chemically modified/activated carbon residues. Blast-furnace slag and metakaolin geopolymers as well as their raw materials, were examined for the simultaneous removal of nickel, arsenic and antimony from the spiked mine effluent. In the case of blast-furnace slag, geopolymerisation clearly increased the efficiency of nickel, arsenic and antimony removal to a beneficial level. The barium chloride modified blast-furnace-slag geopolymer was a very efficient sorbent material for sulphate removal and it could thus be a technically feasible sulphate sorbent for wastewater treatment (e.g. in the mining industry in applications in which very low sulphate levels are desired). Barium chloride modified acid washed analcime could also be a potential sorbent for sulphate removal
Tiivistelmä Teollisuuden jätevedet kuten kaivosvedet ja metalliteollisuuden prosessien jätevedet voivat sisältää monenlaisia haitallisia ja jopa myrkyllisiä aineita kuten metalleja ja sulfaattia. Adsorptiota käytetään yleisesti esimerkiksi metallien ja orgaanisten yhdisteiden poistossa vesiliuoksista, koska se on tehokas ja yksinkertainen menetelmä. Aktiivihiili on yleisimmin käytetty adsorbenttimateriaali vedenpuhdituksessa, mutta sen hinta joissain tapauksissa rajoittaa sen käyttöä. Tämän vuoksi on tarvetta kehittää vaihtoehtoisia adsorbenttimateriaaleja edullisista raaka-aineista. Viime vuosien aikana on raportoitu mm. teollisuus- ja mineraalijätteistä, joita voidaan hyödyntää vesien ja jätevesien puhdistuksessa. Tämän työn tavoitteena oli hyödyntää teollisuudesta muodostuvia jätemateriaaleja (hiilijäännös, metakaoliini, masuunikuona ja analsiimi) raudan, kuparin, nikkelin, arseenin, antimonin tai sulfaatin poistossa malli- ja jätevesistä. Materiaaleja käsiteltiin erilaisilla kemikaaleilla (aktivointi, modifiointi tai geopolymerointi), jotta niiden adsorptiotehokkuudet paranisivivat poistettavia aineita kohtaan. Tulokset osoittivat, että raudan, kuparin ja nikkelin poisto oli sekä käsittelemättömällä että sinkkikloridilla aktivoidulla hiilijäännöksellä korkeampi kuin kaupallisella aktiivihiilellä. Arseenin, nikkelin ja antimonin poistoa kaivosvedestä tutkittiin masuunikuona- ja metakaoliinigeopolymeereillä, joista masuunikuonageopolymeeri osoittautui tehokkaimmaksi metallien poistajaksi. Bariumkloridilla modifioitu masuunikuonageopolymeeri puolestaan poisti erittäin tehokkaasti sulfaattia kaivoksen jätevedestä. Rautakloridilla modifioitu hiilijäännös ja happopesty bariumkloridilla modifioitu analsiimi osoittatuivat myös lupaavaksi materiaaliksi sulfaatin poistossa

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14

Dong, Wei. "Design of advanced industrial furnaces using numerical modeling method." Doctoral thesis, KTH, Materials Science and Engineering, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-2900.

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This doctoral thesis describes the fundamentals ofmathematical modeling for the industrial furnaces and boilersand presents the results from the numerical simulations of sometypical applications in advanced industrial furnaces andboilers. The main objective of this thesis work is to employcomputational fluid dynamics (CFD) technology as an effectivecomputer simulation tool to study and develop the newcombustion concepts, phenomena and processes in advancedindustrial furnaces and boilers. The applications concern onfrom retrofitted conventional grate boilers to the mostadvanced highly preheated and diluted air combustion (HPDAC)furnaces. In this work, several topics are specially concernedwhen applying CFD technology to combustion cases. These topicsare including grate bed model, NO_xmodeling, mixing problem, air staging system, andhighly preheated and diluted air combustion technology. In thiswork, a black-box grate bed model is developed and used inmodeling of grate fired furnaces and boilers. It is based onthe thermodynamic calculations and a set of conservationequations of mass, energy of fuel and air on the grate bed. Oneof benefits of this bed model is simple and feasible to be putinto use in industry. For NO_xmodeling, besides the thermal NO and prompt NO,the HCN route fuel NO has been employed to predict the fuel NOemissions in coal/biomass fired furnaces. In addition, based onNH₃route of fuel NO formation, a SNCR scheme for NO_xabatement has been proposed also. For mixingproblem, the concepts of global degree of mixing and individualdegree of mixing have been proposed and used successfully inpractical applications. The new definition of degree of mixingovercomes some shortages of existed mixing parameters, such asthe mixing factor and the degree of non-mixing, which arenon-normalized and may lose physical meaning in some regions ofthe system. A new air staging system has been studied. It isused to improve the secondary or over-fire air configuration,thus to reduce the pollutant emissions and to enhance thecombustion facilities' efficiencies. In this work, the airstaging system has been employed in coal and biomass combustionfor grate fired furnaces/boilers. The performance of the newair staging system has been evaluated and optimized by usingnumerical modeling method together with physical modelingmethod. Results show that the new air staging system has a goodpotential of improving the combustion quality and reducing thepollutant emissions in industrial furnaces and boilers.Recently, the highly preheated and diluted air combustiontechnology has been regarded as the new generation energytechnology for advanced industrial furnaces and boilers. Inthis work, the highly preheated and diluted air combustionphenomena have been studied by using different numericalmodels. A hybrid procedure of both the large eddy simulationusing subgrid-scale stress Smagorinsky model and the Reynoldsstress model with eddy dissipation model has been alsoinvestigated to study the dynamic combustion process under theconditions of highly preheated and diluted air combustion.Results show that HPDAC technology possesses advantages ofsaving energy and low NO_xemission, thus it has high potential to be usedfor the next generation of industrial furnaces and boilers. Thelarge eddy simulation using subgrid-scale stress Smagorinskymodel together with Reynolds stress model / eddy dissipationmodel are possible to study the HPDAC dynamic process. Finally,this work shows that numerical modeling method is a verypromising tool to deal with the complicated combustionprocesses even for practical applications in industry.

Keywords: air staging, bed model, boiler, burner,computational fluid dynamics (CFD), Ecotube, fuel staging,furnace, grate combustion, highly preheated and diluted aircombustion (HPDAC), large eddy simulation (LES), mathematicalmodeling, nitrogen oxides (NOx), numerical simulation

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15

Yu, Dingli. "Fault diagnosis for industrial systems with emphasis on bilinear systems." Thesis, Coventry University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364163.

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Ströhle, Jochen [Verfasser]. "Spectral Modelling of Radiative Heat Transfer in Industrial Furnaces / Jochen Ströhle." Aachen : Shaker, 2004. http://d-nb.info/1172612382/34.

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17

Bradley, Frederick Joseph. "Thermal shock resistance parameters for the industrial lining problem." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25568.

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A two-dimensional constant heating rate thermoelastic model has been used to develop design and selection criteria for refractory components of linings of high-temperature furnaces and process vessels. The criteria are in the form of resistance to fracture initiation and resistance to damage parameters which account for the influence of thermal and mechanical properties, geometry, and temperature range, while distinguishing between the heating and cooling cases. The resistance to fracture initiation parameter ɸs is the maximum rate at which a shape can be heated or cooled through a specified temperature range without causing fracture. The damage resistance parameter Rd is expressed as the ratio of surface energy per unit area to the elastic strain energy available for crack propagation. Both parameters can be quickly estimated for arbitrary conditions with the aid of tabulated solutions for the maximum principal tensile stress and total strain energy Thermoelastic analyses were used to interpret published results of a variety of thermal shock experiments. Thermal conditions associated with water quenching, radiative furnace heating, gas burners, and controlled heating were simulated using appropriate analytical solutions. Finite element analysis was used to compute maximum principal tensile stresses and elastic strain energy. A simple procedure was developed to invert the stress solution and thereby determine the instant of fracture. Good agreement between thermoelastic predictions and published experimental results with regard to strength retained versus thermal shock relationships, location of fracture, and safe heating rates provided justification for a thermoelastic approach to the thermal shock.
Applied Science, Faculty of
Mining Engineering, Keevil Institute of
Graduate

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18

Hachem, Elie. "Stabilized finite element method for heat transfer and turbulent flows inside industrial furnaces." Paris, ENMP, 2009. http://pastel.paristech.org/5656/01/EH-These.pdf.

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La connaissance du comportement thermique des fours et des pièces est un problème difficile et cependant essentiel dans les thématiques de recherche industrielles actuelles. L'industrie cherche à se doter de moyens numériques de plus en plus efficaces tout en réduisant sans cesse le temps de calcul afin de modéliser des pièces et des assemblages de plus en plus réalistes. Les cinétiques de chauffe ainsi que la distribution de la température dans l'enceinte et dans les pièces traitées doivent également être maîtrisées, afin d'améliorer la qualité des produits chauffées en terme de résistance et dureté. Le travail présenté dans cette thèse porte donc sur le développement de méthodes de résolution numérique pour la simulation du transfert thermique. Ces méthodes permettent le calcul couplé de la température des pièces avec l'environnement du four afin d'optimiser la géométrie de ces pièces, leur position dans le four mais également les conditions initiales de chauffe. Le calcul de dynamique des fluides (CFD) peut être considéré comme un puissant outil technique de prédiction de l'écoulement des fluides et du transfert thermique dans des cas industriels réalistes. La première partie de la thèse porte sur l'étude de schémas numériques avancés relatifs aux méthodes éléments finis stabilisés. Ces méthodes de calculs efficaces ont étaient utilisées pour simuler des écoulements instationnaires et des transferts thermiques conjugués. Par la suite, deux modèles de turbulence (modèle k-epsilon et modèle Large Eddy Simulation) sont introduits et utilisés pour prendre en compte les écoulements complexes et turbulents dans l'enceinte du four. Le transfert radiatif est assuré par la résolution du modèle P1 tout en calculant un terme source volumique qui sera intégré dans l'équation de la chaleur. La deuxième partie de cette thèse se consacre à la mise en place d'une méthodologie de discrétisation robuste qui permet aux utilisateurs de générer de façon entièrement automatique un seul maillage. Ce maillage contient à la fois des domaines axés sur la résolution d'un problème fluide (air, eau, …) mais également solides spécifiques aux structures, et ce quel que soit le niveau de détail et donc de complexité du cas étudié. Cette approche, connue sous le nom d' « immersion de volume », garantit un maillage anisotrope précis aux interfaces fluide-solide afin de capturer plus précisément les gradients thermiques et la forte discontinuité des propriétés physiques. Cette méthode offre donc une grande flexibilité dans la mise en données du problème mixte fluide-structure et aussi dans la prise en compte de plusieurs géométries (four, pièces, supports) et elle est également bien adaptée aux solveurs thermomécaniques développés
The development of efficient methods to understand and simulate conjugate heat transfer for multi-components systems appears in numerous engineering applications and still a need for industrials, especially in the case of the heat treatment of high-alloy steel by a continuously heating process inside industrial furnaces. The thermal history of the load and the temperature distribution in the furnace are critical for the final microstructure and the mechanical properties of the treated workpieces and can directly determined their final quality in terms of hardness, toughness and resistance. The main objectives of this thesis is then to understand and better model the heat treatment process at the same time in the furnace chamber and within the workpieces under specified furnace geometry, thermal schedule, parts loading design, initial operation conditions, and performance requirements. The Computational Fluid Dynamics (CFD) simulation provides a useful tool to predict the temperature evolution and such processes. In the first part of this work, various stabilized finite element methods required for computing the conjugate heat transfer and the incompressible flows are proposed and analyzed. Two turbulence models, the k-epsilon and the Large Eddy Simulations (LES) models were introduced and used to simulate and take into account the complex turbulent flows inside the furnace chamber. The effect of thermal radiation was appropriately accounted for by means of a volumetric model known as the P1-model. In the latter part of this work, a multidomain approach referred as the immersed volume method (IVM) is introduced and applied to treat the fluid-solid interactions. It is based on the use of an adaptive anisotropic local grid refinement by means of the level-set function to well capture the sharp discontinuities of the fluid-solid interface. The proposed method showed that it is well suited to treat simultaneously the three modes, convective, conductive and radiative heat transfer that may interfere in both the fluid part and the solid part using anisotropic finite element meshes

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19

Bayer, Steffen Christoph. "Cleaning up the furnace : patterns of environmental management in the British, Czech and German steel industries." Thesis, University of Sussex, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366107.

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20

Bosnjak, Vjekoslav. "Waste Heat Recovery in Intensive Small and Medium Sized Industries : Case Study - Gästrike Härdverkstad." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-13816.

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In order to keep a high level and to stay competitive in the world market in the future, it is important for the Swedish steel industry to improve their efficiencies continuously and to reduce the energy consumption. In order to realize these goals, the Swedish steel association Jernkotoret was found and by their initiative Triple Steelix was found in 2006 in Berglanden, a significant area for the steel industry. In 2009, the Clean Production Centre was found in Hofors in order to build a cluster of local steel manufacturers, factories and companies. One of those companies is Gästrike Härdverkstad, a small steal heat treatment industry with six employees and about 700.000 tons treated materials every year. The aim for this thesis is to suggest solutions for recovering waste heat and lowering the total energy consumption in furnaces for heat treatment in the case of Gästrike Härdverkstad. Some limitations were necessary to complete the analysis and to come to conclusions. The yearly treated material and energy prices were assumed to be constant and the yearly power consumption was estimated by an extrapolation of a one to five days measurement. Gästrike Härdverkstad is located in Uhrfors, the southern part of Åshammar, a village with 727 inhabitants. There are not any buildings with a possibility to supply heat and there is no district heating in the surroundings. The company has a power consumption of 1.40 GWh/year, of which 65.7% is consumed by the 12 main furnaces. The rest is used by eight seldom used furnaces, devices and auxiliary machines of the support process like fans, pumps, compressor, office heating, and some other. The efficiencies of the main furnaces are between 10% and 20%.The estimated energy consumption of the space heating is about 27 MWh/year, which completely can be covered by the material coolant and the combustion heat of the exhaust gases from the hardening furnaces. Since there are 10 different types of furnaces with different duties and efficiencies, the preheating furnace was taken as an example and compared with a new furnace. According to the needs of Gästrike Härdverkstad, the furnace VAW 60/100-650°C from the company Vötsch was chosen at the cost of 248,827 SEK. The payback time depends on the efficiency. With an efficiency of 40% the payback time would be about 13 years, see Figure 20. After the annealing and ageing, the finished products are cooled down in the building hall by the ambient air. In future, the possibility of preheating the material with the heat of the finished products should be considered. With an efficiency of 30.87%, one preheating furnace could bereplaced, and taken a payback time of 5 years into account; the price of the construction would be allowed to be up to 253,200 SEK.

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21

CARVALHO, ELITA F. U. de. "Desenvolvimento de um absorvedor inorganico solido para reduzir a emissao de fluoreto na industria ceramica." reponame:Repositório Institucional do IPEN, 2004. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11180.

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Made available in DSpace on 2014-10-09T12:49:16Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T14:00:32Z (GMT). No. of bitstreams: 1 09809.pdf: 7318754 bytes, checksum: 166979fe7dbb592b70e1bc5fb8417a96 (MD5)
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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22

Mølnås, Håvard. "Compatibility Study of Carbon-Based Refractory Materials utilized in Silicomanganese Production Furnaces." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for materialteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-16345.

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Tap hole refractories constitute critical parts of the refractory lining in submerged arc furnaces. For several hours every day, molten slag and metal flow through the tap hole calling for thorough selection of refractory materials able to withstand the intense thermal, corrosive and erosive conditions present in this area. Carbon-based refractories have shown excellent thermal properties and high strength, as well as low wettability towards process materials, and are therefore utilized in silicomanganese production furnaces both as side lining, in the hearth, and in the tap hole area. The aim of this investigation was to determine the compatibility of five refractory materials utilized in the tap hole area of an industrial silicomanganese furnace with two industrial silicomanganese slags: •Investigate the suitability of the selected refractory materials for confining the process materials during industrial production of silicomanganese alloys. •Identify critical refractory wear mechanisms upon slag-refractory interaction at industrial tapping temperatures.Compatibilities were investigated through 12 static crucible tests and two static plate tests in a vertical tube furnace redesigned during this investigation. Slag-refractory interaction was studied after two and four hours holding time at 1367°C ± 1.8°C, 1464°C ± 2.1°C and 1600°C - 0.6°C /+ 0.2°C. Holding temperatures were verified through the wire-bridge method at the melting points of gold and palladium. Visual inspection, as well as optical microscopy and SEM, were utilized to examine the samples after heat treatment.During compatibility experiments, dissolution of refractory matrix due to solubility of oxide refractory binder phases in silicomanganese slags was observed, as well as disintegration of refractory particles due to gas formation at slag-refractory interface, or expansion as a result of phase transformations in refractory material. Direct reduction of manganese oxide from slags and iron oxide present in refractories by carbon and silicon carbide was also observed. Establishment of partial slag-metal equilibriums between iron oxide and silicon metal originally present in slag was observed, as well as formation of silicon carbide at the slag-refractory interfaces. The latter may serve to protect the refractory from wear caused by slags.Based on observations of extensive interaction between silicomanganese slag sample I and ramming paste at 1600°C, the ramming paste investigated cannot be recommended for usage during tap block repair in an industrial silicomanganese furnace. Incipient electrode paste disintegration by slags and silicon carbide tap block – slag interaction were observed after compatibility tests at 1464°C, calling for further investigations of these refractory materials. Tap hole clay and carbon tap block showed minimal signs of interaction with process materials at 1464°C. Refractory porosity seemed to have a larger effect on refractory wear than refractory ash content. Contrary to industrial observations, silicomanganese slag sample I was more corrosive towards the ramming paste and electrode paste investigated than silicomanganese slag sample II.

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23

Gagnon, Éric. "Modélisation de la turbulence dans des ecoulements de plasma en milieu industriel /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1996. http://theses.uqac.ca.

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24

Perron, Jean. "Modélisation mathématique simplifiée d'un four de métal chaud /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1987. http://theses.uqac.ca.

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25

Lavoie, Yvon. "Modélisation tri-dimensionnelle et en régime transitoire des fours d'homogénéisation /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1993. http://theses.uqac.ca.

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26

Erchiqui, Fouad. "Modelisation mathematique d'une chambre de combustion par la methode des plans imaginaires." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1987. http://theses.uqac.ca.

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Memoire (Sc. A.) --Universite du Quebec a Chicoutimi, 1987.
En tete du titre: Memoire presente a l'Universite du Queec a Chicoutimi comme exigence partielle pour l'obtention du grade de maitre es sciences appliquees. CaQCU Bibliogr.: ff. 60-61. Document électronique également accessible en format PDF. CaQCU

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27

Menozzi, Sunny. "Preserving the ethos of industry at the Carrie furnaces: the redevelopment of an industrial heritage site and the interpretation of manufacturing culture." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/99093.

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Thesis: M.C.P., Massachusetts Institute of Technology, Department of Urban Studies and Planning, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 103-110).
This thesis proposes design principles and a program for site of the Carrie Blast Furnace Plant, a National Historic Landmark in Pittsburgh's Monongahela Valley. The Redevelopment Authority of Allegheny County intends to redevelop this 168-acre former industrial site in the near future. In anticipation of this regionally important redevelopment project, this thesis considers the philosophical commitments of historic preservation, weighs economic growth imperatives, explores how the Carrie Furnaces could be made to cultivate public memory of industrialism, and examines competing visions of significance, authenticity, and interpretation of heritage sites, particularly in the context of deindustrialization. Four cases studies of internationally renowned projects demonstrate best practices in the redevelopment of historic blast furnace plants, ironworks, steelworks, and collieries. The Duisburg-Nord Landscape Park and Zollverein Park in Germany, the Belval City of Science project in Luxembourg, and the Parque Fundidora in Mexico all provide lessons in the preservation and adaptive reuse of derelict industrial infrastructure. Though their contexts differ, these four cases offer a common set of best practices to guide the Carrie Furnaces project. First, through designs and programs, these projects interpret the stories of industrial heritage sites for contemporary audiences, thereby cultivating public memory. Second, these projects' adaptive reuse of historic structures and spaces creates new, contemporary relationships between the sites and their various public audiences. This, as well as the fact that the designs are inspired by site-specific characteristics and are decidedly of their places and times, imparts authenticity. Third, these projects promote local economic revitalization through mixed-use development that engages broad constituencies. Finally, the projects use elements that pay homage to the industrial forms, materials, and culture that characterize their places. This paper's proposed development program and design for the Carrie Furnaces site preserves the site's "ethos of industry" through a 21st century manufacturing and tourism program that interprets the Carrie Blast Furnace Plant as a site of historic, vertically-integrated iron and steel production for the contemporary public consciousness. This program also promotes multi-sectoral economic growth, reconnects ailing nearby communities to the site, and conserves the material and cultural aesthetics of steel production, labor, thrift, and enterprise that made industrial Pittsburgh the center of American heavy manufacturing.
by Sunny Menozzi.
M.C.P.

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28

Jain, Pankaj. "Étude du transfert de chaleur convectif dans un four circulaire /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1996. http://theses.uqac.ca.

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29

Myrstener, Erik. "Environmental impacts of early metallurgy in Moshyttan : A study of one of Europe's oldest blast furnaces, using three lakes records in Nora bergslag." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-64733.

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The aim of this study was to assess the environmental effects of Moshyttan, one of the earliest known blast furnaces in Europe (ca. 11th century). The study was based on the analysis of three lake records in the immediate surroundings of the smelter. Fickeln lies directly downstream and is the main recipient of waterborne pollution. Mosjökälla lies directly upstream and served as the main water reservoir for the water-powered bellows. Kramptjärnen lies 1 km to the NW in a separate catchment and acts as a reference. The data includes 31 elements analyzed by X-ray fluorescence spectroscopy (XRF), organic content inferred from loss on ignition (LOI), biogenic silica (BSi) modeled from Fourier-transform infrared spectroscopy (FT-IRS) for all lakes and diatom counts for Fickeln. Two other studies provided dating of slag from the smelter and pollen- and geochemical data from Fickeln. The results show that the metallurgy and associated activities (e.g. agriculture, forest grazing and charcoal production) led to eutrophication and alkalization in Fickeln. This is indicated by the diatom community that in the background is dominated by benthic genera indicative of oligotrophy and dystrophy (Frustilia, Brachisyra and Eunotia) that during the active smelter phase is replaced by pelagic genera indicative of eutrophy (Aulacoseira and Asterionella). BSi also decreases after smelter establishment, which speculatively could indicate an overall decrease in diatom production. At the same time, a suite of elements commonly associated with iron processing (Fe, Pb and Zn) increase in the sediment.

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30

Rafaralahy, Hugues. "Modélisation d'un processus thermique et reconstruction de l'état et des défauts pour une classe de systèmes à paramètres distribués de type parabolique." Nancy 1, 1993. http://www.theses.fr/1993NAN10223.

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Les travaux présentés dans ce mémoire concernent d'une part la modélisation et la simulation numérique d'un processus thermique industriel et, d'autre part, la reconstruction de l'état et le diagnostic pour une classe de systèmes à paramètres distribués de type parabolique. Dans une première partie, la modélisation d'un four de réchauffe de billettes, de type poussant, alimenté au gaz naturel est réalisée. Ce modèle est un système à paramètres repartis de type parabolique décrivant la conduction de la chaleur avec des conditions aux frontières de type Fourier non linéaires représentant les transferts de chaleur par convection et rayonnement. Pour mettre en évidence les fluctuations de température sur la longueur des billettes (nécessaire à l'optimisation de la qualité du produit et des conditions de laminage) nous considérons un modèle à deux dimensions d'espace. Un algorithme d'intégration numérique, permettant d'analyser les fluctuations du profil de température et de simuler l'évolution thermique des billettes pendant la phase de chauffe, est proposé. La deuxième partie est consacrée à la synthèse d'observateurs de l'état de dimension finie pour les systèmes de dimension infinie évoqués ci-dessus en passant par une réduction de la dimension de ces systèmes via les polynômes orthogonaux généralisés. L'approche adoptée est basée sur les observateurs à grand gain des systèmes localisés. La robustesse de celle-ci par rapport aux erreurs de modélisation des paramètres est étudiée. Une version d'ordre réduit de cet observateur est proposée. La troisième partie concerne l'estimation simultanée de l'état et des défauts. Deux cas sont considères, à savoir les défauts de mesures de type ponctuel (biais, dérivés de capteurs. . . ) Et les défauts de système de type distribue. Aucune hypothèse a priori n'est faite sur la dynamique de ces défauts. La solution proposée est basée sur l'observation de l'état des systèmes singuliers non linéaires localisés. Un de nos principaux objectifs est de proposer des solutions réalisables sur calculateurs, donc de dimension finie

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Silva, Anderson Badia da. "Utilização de carepas como componente da carga de um forno elétrico a arco." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/77730.

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As atividades industriais geram uma série de resíduos, muitos dos quais passíveis de reciclagem. Na indústria siderúrgica, em operações de lingotamento e conformação mecânica, forma-se uma casca sólida quebradiça, conhecida como carepa, a qual é originada a partir da oxidação da superfície do aço quando submetido ao gradiente térmico. Constituída por óxidos de ferro, portanto, carrega o elemento essencial para fabricação do aço. Esse trabalho se utilizou de análises, ensaios laboratoriais e testes industriais para direcionar a reciclagem da carepa de uma usina siderúrgica no próprio forno elétrico a arco. Foram analisadas as propriedades físicas e químicas do material, e nos ensaios de redutibilidade em laboratório o comportamento da carepa foi observado frente à mistura com um agente redutor. Em escala industrial a carepa foi introduzida no forno elétrico a arco juntamente com a sucata de carregamento, e o comportamento das principais variáveis do processo foram avaliadas. Pelo entendimento da sua influência sobre o processo foi possível determinar a viabilidade de promover a reciclagem do resíduo no próprio processo siderúrgico. As carepas geradas na planta siderúrgica se distinguiram, essencialmente, quanto ao tamanho de partícula e teor de umidade. Quimicamente, as amostras são semelhantes, com teor de ferro mínimo de 70%. Na sua composição, predominaram óxidos de hematita, magnetita e wustita, sendo este último o de maior importância. Nos ensaios de autorredução em laboratório, foram constatados melhores resultados para fração reagida e grau de metalização quanto mais alta a temperatura de ensaio. Nos testes em escala industrial, a adição de 1% de carepa na carga comprovou que não houve influência sobre o consumo de energia elétrica e o teor de FeO da escória. A desfosforação do aço líquido foi positivamente afetada com percentual médio de fósforo reduzido em 15% com utilização de carepa. Por outro lado, o indicador de rendimento metálico sofreu impacto negativo, evidenciando a necessidade de avaliações complementares para determinar a reciclagem deste resíduo no forno elétrico a arco.
Industrial processes generate several residues and many of them are suitable for recycling. In the steel industry, casting operations and mechanical forming originate a solid brittle layer of oxide known as scale, which is produced by oxidation of the steel surface when exposed to a thermal gradient. Consisting of iron oxides, it therefore holds the essential element for steel manufacturing. This study performed analysis, laboratory trials and industrial tests to investigate scale recycling in an electric arc furnace. Chemical and physical properties of the material were analyzed and, at reducibility laboratory trials, the behavior of the scale was observed when mixed with a reducing agent. In industrial tests, the scale was introduced in an electric arc furnace mixed with the loaded scrap and the behavior of the main process variables was evaluated. By understanding its influence on the process, it was possible to determine the feasibility of scale recycling in steelmaking. The scales generated in the steel plant were distinguished mainly by the particle size and moisture content. Samples were chemically similar, with minimum 70% iron content. In its composition predominate hematite, magnetite and wustita oxides, the latter being the most important. In self-reduction laboratory tests, the best results for fraction reacted and metallization grade were reached with the highest temperatures. In industrial tests, with 1% scale added to the scrap, there was no influence in the electric energy consumption or FeO content of the slag. The liquid steel dephosphorization was positively affected since the average phosphorus percentage was reduced by 15% with the scale utilization. However, the yield indicator suffered negative impact, suggesting the need for further assessments to determine the scale recycling feasibility in electric arc furnace process.

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Commandré, Isabelle. "L'artisanat du verre en Bas‐Languedoc du XVIe au XVIIIe siècle." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM3041.

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L’artisanat verrier forestier moderne connaît un développement particulièrement important dans la région languedocienne qui bénéficie d’une tradition ancrée depuis le XIIIe s. Pour autant, les modes et structures de production sont encore peu documentés et l’historiographie en livre généralement l’image d’un modeste réseau d’officines isolées. Fondée sur la complémentarité des sources écrites, archéologiques et archéométriques, cette étude privilégie l’analyse de ces fabriques à partir de huit ateliers fouillés. Elle livre une approche des divers acteurs comme de l’environnement qui contribuent à la structuration formelle de cet art du feu. Une centaine de centres de production modernes a été recensée, le plus souvent rassemblés en foyers. Si leur développement demeure limité, ils font en revanche état d’une certaine autonomie dans la production. De la plus petite unité forestière aux grands établissements assimilés à des centres villageois, chaque site assure le cycle complet de la production du verre. Les ateliers bénéficient en général d’infrastructures relativement simples, rassemblées autour de deux à trois fours à vocation complémentaire : préparation des matières, fusion et recuit. Leur morphologie ainsi que les usages combinés qui en sont faits varient en fonction des époques et de l’importance de la fabrique. Terre propice à l’établissement de l’industrie verrière pour ses nombreuses ressources naturelles, le Languedoc moderne produit principalement du verre creux destiné à alimenter la province. Toutefois, à partir du premier tiers du XVIIIe s., cet artisanat forestier s’étiole progressivement au profit de grandes manufactures alimentées au charbon de terre
The modern woodlands glassmaking enjoys a particularly siginifant development in the Lower Languedoc region which benefits from a deeply rooted tradition from the thirteenth century on. However, the ways and structures of production are as yet very poorly documented and the historiography generally gives a picture of a modest network of workshops producing objects for daily use.Based on the additionnal information of written archaeological and archeometrical sources, this study favours the analysis of these factories from eight excavated sites. At first place it gives an approach of the people as well as the surrounding area which shows the formal structuring of this ceramic skillset. About a hundred moderns production centres emerged, grouped together in a number of zones with several workshops near each other. Their extent is limited, on the other hand they indicate a certain autonomy in production. From the smallest unit in the woodlands to the big establishments which resembledl proper village settlements, each site ensured the complete cycle of the operational chain of glass production. Generally, the workshops were a relatively simple infrastructure assembled around two or three furnaces with complementary functions: frit, fusion and annealing furnaces.As a region favourable to the establishment of glassmaking due to the rich resources in raw materials, modern Languedoc produced mainly hollow, concave glass.. Basically their production supplied the province which was the biggest of the kingdom. It is only from the first third of the eighteenth century that this woodland craft industry declined progressively as big coal-fired factories took over

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Fillion, Claude. "Développement d'un système de contrôle pour un four virtuel par automate programmable /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 2002. http://theses.uqac.ca.

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Dufour, Amélie. "Multivariate statistical modeling of an anode backing furnace : Modélisation statistique multivariée du four à cuisson des anodes utilisées dans la fabrication d'aluminium primaire." Master's thesis, Université Laval, 2016. http://hdl.handle.net/20.500.11794/26844.

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La stratégie actuelle de contrôle de la qualité de l’anode est inadéquate pour détecter les anodes défectueuses avant qu’elles ne soient installées dans les cuves d’électrolyse. Des travaux antérieurs ont porté sur la modélisation du procédé de fabrication des anodes afin de prédire leurs propriétés directement après la cuisson en utilisant des méthodes statistiques multivariées. La stratégie de carottage des anodes utilisée à l’usine partenaire fait en sorte que ce modèle ne peut être utilisé que pour prédire les propriétés des anodes cuites aux positions les plus chaudes et les plus froides du four à cuire. Le travail actuel propose une stratégie pour considérer l’histoire thermique des anodes cuites à n’importe quelle position et permettre de prédire leurs propriétés. Il est montré qu’en combinant des variables binaires pour définir l’alvéole et la position de cuisson avec les données routinières mesurées sur le four à cuire, les profils de température des anodes cuites à différentes positions peuvent être prédits. Également, ces données ont été incluses dans le modèle pour la prédiction des propriétés des anodes. Les résultats de prédiction ont été validés en effectuant du carottage supplémentaire et les performances du modèle sont concluantes pour la densité apparente et réelle, la force de compression, la réactivité à l’air et le Lc et ce peu importe la position de cuisson.
The aluminum manufacturing process is highly influenced by the anode quality. Several factors affect the anode quality and the actual quality control strategy is inadequate to detect faulty anodes before setting them in the electrolytic cells. A soft-sensor model developed from historical carbon plant data and multivariate statistical methods was proposed in past work to obtain quick predictions of individual anode properties right after baking for quality control purposes. It could only be used for anodes baked at the coldest and hottest positions within the furnace due to the core sampling strategy used at the partner’s plant. To complement the soft-sensor, this work proposes a method for taking into account the thermal history of anodes baked at eventually any position and to allowing for the prediction of properties for all anodes. It is shown that combining categorical variables for pit and baking positions and routinely available firing equipment data is sufficient for predicting the temperature profiles of anodes baked in different positions (measured during pit surveys) and account for its impact on anode properties. Prediction results were validated using core sampling and good performance was obtained for LC, apparent and real density, compressive strength and air reactivity.

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Samuelsson, Peter. "Management of technology in the process industries: Matching market and machine." Doctoral thesis, KTH, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-199705.

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The process industries span multiple industrial sectors and constitute a substantial part of the entire manufacturing industry. Since companies belonging to this family of industries are often very asset intensive, their ability to respond to changes is often limited in the short term. The adaptation of the capabilities of existing processes, and conversely finding products and market segments to match the production system capabilities, are an important part of product- and market development activities in the process industry. The importance to companies in the process industry of having a well-articulated manufacturing strategy congruent with the business strategy is second to none. However, to facilitate manufacturing strategy developments, it is essential to start with an improved characterization and understanding of the material transformation system. To that end an extensive set of variables was developed and related measures and scales were defined. The resulting configuration model, focusing on company generic process capabilities in the process industries, is to be regarded as a conceptual taxonomy and as a proposition available for further testing. The usability of the model was subsequently assessed using “mini-cases” in the forestry industry, where the respondents confirmed that the company’s overall strategy could benefit from this kind of platform as a possible avenue to follow. The model was deployed as an instrument in the profiling of company material transformation systems to facilitate the further development of companies' functional and business strategies. The use of company-generic production capabilities was studied in three case companies representing the mineral, food and steel industries. The model was found by the respondents to be usable as a knowledge platform to develop production strategies. In the final analysis of the research results, a new concept emerged called “production capability configuration": A process-industrial company’s alignment of its generic production capabilities in the areas of raw materials, process technology and products to improve the consistency among the variable elements that define operations and improve the congruence between operations and its environment. From the perspective of value creation and capture, firms must be able to manufacture products in a competitive cost structure within the framework of a proper business model. By using the configuration model, the relationship between manufacturing and innovation activities has been studied in the previously mentioned three case studies. In many cases the gap in capability appears as a limitation in the production system, requiring development efforts and sometimes investments to overcome. This is illustrated with two examples from the steel industry, where development efforts of the production system capabilities are initiated to better match the market demands. One example is the increase the volume- and product flexibility of an existing stainless steel melt shop, resulting in a proposed oblong Argon Oxygen Decarburisation (AOD) converter configuration that was subsequently verified using water modelling. The second example is from a carbon steel mill, where the target was to increase the raw material- and volume flexibility of another melt shop, by modifying the capabilities of the Electric Arc Furnace (EAF). Enabling EAF technologies are further described and evaluated using operational data and engineering type of estimates.

QC 20170116

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Bagatini, Maurício Covcevich. "Estudo de reciclagem da carepa através de briquetes autorredutores para uso em forno elétrico a arco." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/37372.

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A presente tese teve como objetivo fornecer subsídios teóricos e experimentais com vistas à reciclagem da carepa gerada em usinas mini-mills através de briquetes autorredutores para uso em FEA. Para atingir os objetivos vislumbrados, o trabalho foi estruturado em quatro principais tópicos: estudo de caracterização e de redutibilidade da carepa, escolha e caracterização do redutor para uso nos briquetes, elaboração e caracterização da mistura e ensaios de laboratório para avaliação do desempenho dos briquetes autorredutores. Os estudos de caracterização da carepa indicaram que este resíduo é constituído principalmente de wustita e se apresenta estratificada em três camadas: camada externa fina e porosa composta de hematita e magnetita, camada intermediária de wustita densa e camada interna de wustita porosa. A cinética de redução da carepa foi investigada em termobalança no intervalo de temperatura entre 830 e 1200°C com CO puro e mistura 90%CO-10%CO2. A energia de ativação aparente encontrada nesses ensaios variou de 71 a 80 kJ/mol e as observações microscópicas demonstraram que a redução da carepa segue um modelo topoquímico. A escolha do agente redutor para compor o briquete se deu através de ensaios de gaseificação ao CO2 e de autorredução em termobalança com três tipos de material carbonoso. A partir desses ensaios observou-se a seguinte ordem decrescente de reatividade e respectivas energias aparentes de ativação: Carvão Vegetal (Ea = 237 kJ/mol), Carvão Mineral (Ea = 214 kJ/mol) e Coque de Petróleo (Ea = 335 kJ/mol). Em virtude da maior reatividade do Carvão Vegetal frente aos demais, este redutor foi escolhido para uso nos briquetes. A mistura utilizada na confecção dos briquetes autorredutores teve como constituintes principais a carepa, os finos de carvão vegetal e aglomerantes (melaço e cal). Ensaios de caracterização em termobalança com atmosfera oxidante e aquecimento rápido indicaram uma perda de massa de cerca de 40%, referente às etapas de secagem, desvolatilização e autorredução da mistura. Nesses ensaios, observou-se elevadas taxas de perda de massa da mistura e uma notável complexidade dos fenômenos envolvidos, com reações simultâneas de combustão, autorredução e de oxidação do ferro, prevalecendo uma ou outra, dependendo da temperatura e da fração reagida de amostra. Através de procedimentos que buscaram reduzir a complexidade dos fenômenos envolvidos nas condições oxidantes, foi possível estimar que a energia de ativação aparente de autorredução está entre 62 e 69 kJ/mol. Os briquetes produzidos em escala industrial foram submetidos a ensaios isotérmicos e não-isotérmicos de alta temperatura. Tais ensaios buscaram determinar os gradientes térmicos no interior do briquete, a energia de ativação aparente e o desempenho cinético do aglomerado em condições de temperatura que se aproximam da prática industrial. A partir das constatações concernentes às taxas das reações químicas individuais (redução e gaseificação), às medidas do perfil de temperatura no interior dos aglomerados, à energia de ativação estimada para o briquete (93 kJ/mol) e ao modelo de redução encontrado nos ensaios de alta temperatura, acredita-se que tanto a cinética de redução da carepa como a transferência de calor sejam obstáculos limitantes da cinética global dos briquetes em estudo. Finalmente, os resultados de metalização obtidos nos testes de alta temperatura dão indícios da possibilidade de uso destes briquetes em FEA.
This dissertation aimed to provide theoretical and experimental basis for recycling of mill scale generated in mini-mill plants through the use of self-reducing briquettes in EAF. To reach these goals, the work was structured around four main topics: characterization and reducibility study of scale, choice and characterization of the reductant to use in briquettes, elaboration and characterization of the mixture and laboratory tests to performance evaluation of self-reducing briquettes. The characterization studies of mill scale have indicated that this waste is composed mainly of wustite and is stratified into three layers with different morphologies: fine porous external layer composed of hematite and magnetite, intermediate layer of dense wustite and inner layer of porous wustite. The kinetics of scale reduction was investigated in thermobalance in a temperature range from 830 to 1200°C with pure CO and a mixture of 90% CO and 10% CO2. The apparent activation energy obtained in these tests ranged from 71 to 80 kJ/mol and the microscopic observations showed that the mill scale reduction corresponds to a topochemical model. The choice of the reductant for composing the briquette was made through tests of gasification with CO2 and of self-reduction in thermobalance with three different carbonaceous materials. From the results, it was observed the following decreasing reactivity order and the related apparent activation energy: Charcoal (Ea = 237 kJ/mol), Mineral Coal (Ea = 214 kJ/mol) and Petroleum Coke (Ea = 335 kJ/mol). Due to the higher reactivity of Charcoal in relation to the others, this reducer was chosen to be used in the briquettes. The main constituents of the mixture used in the manufacture of self-reducing briquettes were scale, charcoal and binders (melasse and lime). The characterization tests in thermobalance with oxidizing athmosfere and rapid heating indicated a mass loss of about 40%, referring to the stages of drying, devolatilization and self-reduction of the mixture. During these tests, it were observed high rates of mixture loss mass and a remarkable complexity of the phenomena, with simultaneous combustion, self-reduction and iron oxidation reactions, where their importance changes according to temperature and fractional reaction of the sample. Through the procedures that aimed to reduce the complexity of the related phenomena in oxidant conditions, it was possible to estimate that the self-reduction apparent activation energy ranges between 62 to 69 kJ/mol. The briquettes produced in the industrial plant were submitted to isothermal and nonisothermal tests of high temperatures. Such tests aimed to determine the thermal gradients into the briquette, the apparent activation energy and kinetic performance of the agglomerate in temperature conditions similar to the ones used in industrial practice. Based on the findings concerning the individual rates of chemical reactions (reduction and gasification), the measures of the temperature profile inside the briquettes, the activation energy estimated (93 kJ/mol) and the reduction model found in high-temperature tests, it is assumed that both the kinetics of mill scale reduction and heat transfer limit the overall kinetic rates of these briquettes. Finally, the results of metallization obtained in the tests conducted at high temperatures indicate the possibility of using these briquettes into the EAF.

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Larouche, Andre. "Couplage de la methode des plans imaginaires en trois dimensions et du logiciel phoenics pour la modelisation de la chambre de combustion de fours industriels." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1988. http://theses.uqac.ca.

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Memoire (M.Sc.A.) --Universite du Quebec a Chicoutimi, 1988.
En tete du titre : Memoire presente a l'Universite du Quebec a Chicoutimi comme exigence partielle de la maitrise en ressources et systemes. CaQCU Document électronique également accessible en format PDF. CaQCU

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Alekseev, Kirill. "Hazardous bauxite residue, blast furnace slag, and foundry sand application as the main components for environmentally friendly red ceramics production." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2868.

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Nesta pesquisa foram utilizados resíduos da produção de alumínio e ferro. Resíduo de bauxita, que também é chamado de rejeitos de bauxita ou lama vermelha, e escória siderúrgica são os principais resíduos da indústria metalúrgica. Também foi utilizada areia de fundição, que é um resíduo do processo de fundição. Estes três componentes foram utilizados em conjunto para desenvolver material cerâmico de construção. A idéia principal era usar apenas resíduos industriais, sem materiais naturais tradicionais. Os residuos de vidro e as cinzas de madeira foram adicionados às composições para deminuir o ponto de fusão das amostras. Na pesquisa, 24 composições foram queimadas a 800-1225°C e suas propriedades foram estudadas. As características mecânicas das amostras foram analisadas através do teste de resistência à flexão, medindo-se a absorção de água, densidade e retração linear. As propriedades físico-quimicas foram estudadas por XRF, XRD, AAS, SEM, EDS, LAMMA, mapeamento, DTA e TGA. O principal motivo para os resultados elevados de resistência à flexão (19,78 MPa) das amostras foi identificado como o desenvolvimento de novas formações amorfas. Como resultado da pesquisa, algumas composições foram sugeridas para a produção específica de materiais de construção. Composições contendo lama vermelha (40- 100%), escória siderúrgica (0-50%), areia de fundição (0-50%), resíduo de vidro (0-20%) e cinzas de madeira (0-20%), atenderam normas e regulamentos brasileiros para materiais de construção, podem substituir materiais cerâmicos tradicionais, que envolvem a enorme exploração de recursos naturais.
In the presented research were used residues of aluminum and iron production. Bauxite residue, which is also called bauxite tailings or red mud, and blast furnace slag are the key wastes of metallurgical industry. There was also used foundry sand, which is a residue of casting process. These three components were used together to develop ceramic construction material. The main idea was to use industrial wastes only, no traditional natural materials. The waste glass and wood ash were added to the compositions in order to decrease melting point of the samples. In the research 24 compositions were sintered at 800-1225°C and their properties were studied. Their mechanical characteristics were analyzed using flexural strength test, measuring water absorption, density, and linear shrinkage. Physicochemical properties were studied by XRF, XRD, AAS, SEM, EDS, LAMMA, mapping, DTA, and TGA. The main reason for high results of flexural strength (19.78 MPa) of the samples was identified as a development of new amorphous formations. As a result of research, some compositions were suggested for specific construction materials production. Compositions containing red mud (40-100%), blast furnace slag (0-50%), foundry sand (0-50%), waste glass (0-20%), and wood ash (0-20%), according to Brazilian Norms and regulations for construction materials, may substitute traditional ceramic materials, which involve enormous exploration of natural resources.

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Hadid, Baya. "Développement de capteurs logiciels pour procédés industriels par estimation paramétrique." Thesis, Poitiers, 2014. http://www.theses.fr/2014POIT2305.

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Cette thèse a été financée par l’ANR au travers du programme Efficacité énergétique et réduction des émissions de CO2 dans les systèmes industriels. Le projet CHIC - CHaîne de mesure Innovante à bas Coût - initié et porté par EDF R&D a pour objectifs de concevoir une chaîne de mesure innovante à faible coût et non-intrusive, permettant de détecter des dérives de consommation avecune justesse de mesure de l'ordre de 5%. Cette thèse est consacrée à la mise en œuvre de capteurs logiciels pour des mesures de puissance et de débits. Trois sous-ensembles ont permis de mener des essais en situation quasi-industrielle : un four électrique, une chaudière à gaz et un compresseur d'air. L'application sur le four électrique a porté sur l'estimation de la puissance électrique et ladétection de défauts à partir des mesures disponibles en utilisant de l’estimation en boucle fermée du modèle du four à vide et en charge. L'estimation de débits a été menée sur une chaudière industrielle et un compresseur d'air. Les paramètres des modèles variant en fonction d’autres grandeurs telles que la pression, la température et le taux d’humidité, une approche LPV a été proposée. Une approche non-paramétrique à l'aide de processus gaussiens est également étudiée dans le cas de la chaudière. Le capteur de débit de gaz a été validé sur site via une implémentation directe en C# dans l'automate de contrôle du processus. Dans le cas du compresseur, l'étude de cette variation paramétrique en fonction de la température, l’humidité et la pression de refoulement de l’air a été menée. Ces premières études ont montré la faisabilité des différents capteurs logiciels permettant d'atteindre les objectifs fixés
This thesis was funded by the ANR through the Energy Efficiency and reduction of CO2 emissions in industrial systems program. The CHIC - CHaîne de mesure Innovante à bas Coût - project initiated and supported by EDF R&D aims to develop and test an innovative low cost and nonintrusive measuring system to monitor and analyze the consumption of energy fluids used in industrial sites in order to detect consumption drifts with a measurement accuracy of about 5%. This thesis focuses on the soft sensors implementation for power and flow measurements. Three subsets were used to carry out experiments in an almost industrial situation: an electric furnace, a gas boiler and an air compressor. The electric furnace application was on the electric power estimation and fault detection using a closed-loop estimation of the furnace model from the set and inner temperatures and the control signal of free-load and load tests. The flows estimation was conducted on an industrial boiler and an air compressor. Since the models parameters depend on other variables, a static LPV approach is proposed. On the boiler, the gas flow is estimated from the valve control and the gas pressure and temperature using different valve types. A non-parametric approach using Gaussian processes is also studied on this subset. The gas flow sensor has been validated on-site using a direct implementation in C# on the PLC process control. On the compressor, the parametric variation study according to the air temperature, humidity and discharge pressure has been conducted on simulation and real data. These early studies have shown the feasibility of the different soft sensors to achieve the fixed objectives

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Dubuisson, Carine. "Cinétique de la calcination du coke de pétrole en atmosphére oxydante /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1993. http://theses.uqac.ca.

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Alp, Baris. "Utilization Of Ggbfs Blended Cement Pastes In Well Cementing." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614683/index.pdf.

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In well cementing, the cement slurry is exposed to the conditions far different than those of ordinary Portland cement (PC) used in construction. After placement, hardened cement paste should preserve integrity and provide zonal isolation through the life of the well. American Petroleum Institute (API) Class G cement is the most common cement type used in various well conditions. Class G cement has a high degree of sulfate resistance which makes it more stable than PC when subjected to the compulsive well conditions. Ground granulated blast furnace slag (GGBFS) blended cement has a long history of use in the construction industry, but is not extensively used in well cementing applications. This study presents an experimental program to investigate the applicability of CEM I and GGBFS blended cement pastes in the well cementing industry. Class G cement and blends of CEM I and GGBFS with the proportions (80:20), (60:40), (40:60) and (20:80) are prepared with same water/cement ratio (0.44) as restricted for Class G cement in API Specification 10A to be tested. The cement pastes are cured for ages of 1 day, 7 days and 28 days at 80

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Racková, Eliška. "Areál bývalého šamotového závodu MŠLZ Mladějov na Moravě - funkční využití areálu pro potřeby Průmyslového muzea Mladějov." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2010. http://www.nusl.cz/ntk/nusl-215644.

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The design goal is to propose future utilisation of large former industrial site containing heterogeneous set of manufacturing, service and dwelling buildings of different age and qualities. Also the site is heterogeneous itself – the old industrial grounds which are quite well maintained and long-term used apart from the new part – which has been conquered in hurry in the 60’ and now quickly disappearing in birch succession forest. The difference is reflected not only in site use design, but also in architectural solution of singular buildings. Buildings in the old part serv to the needs of Museum and its further activities and reacts to the style defined by Lichtenstein period architecture – power station and steam plant. Different pattern of each building aimed to utilization of the full building renovation approaches spectrum, ranging from steam plant conservation to analogical installation in the power plant to analogical reconstruction od wooden floor of the old furnance. Question of use and design of the blast furnances is far more complex and became the main topic of this work. The furnance approaches much more the LTO area than building one. It includes only two standard building spaces (threshers), the rest is taken by machinery or closed and inaccessible. The building character predestinates the furnances to become a archeologized monument. The design goal was to use the time still remaining for this unique structure with the intensity possible from the safety and functioning views. In the first stage, the furnance will house a community of artists, other creative or interested people functionally parallel to Cartuzian order monasteries. The housing units will be built in the powdery reservoirs, the common rooms in the threshers. A parallel to the chapel will be the furnance base – being accessible to the public. Every reservoir unit consists of two containers, winter garden and own garden space, every one is a miniature, but fully self sufficient unit surrounded by its own little universe, as the Cartusian idea requires. The main construction used will be the shipping containers, adapted for dwelling, put on suspended “cradles”. The unused rest of the reservoir space will be used as gigantic flower pot. In time, the roles of the spaces will change. The communication spaces of the former community house will become the only access to the furnance spaces and the corridor will remain half open as a view platform.

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El, Jannoun Ghina. "Adaptation anisotrope précise en espace et temps et méthodes d’éléments finis stabilisées pour la résolution de problèmes de mécanique des fluides instationnaires." Thesis, Paris, ENMP, 2014. http://www.theses.fr/2014ENMP0077/document.

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Aujourd'hui, avec l'amélioration des puissances de calcul informatique, la simulation numérique est devenue un outil essentiel pour la prédiction des phénomènes physiques et l'optimisation des procédés industriels. La modélisation de ces phénomènes pose des difficultés scientifiques car leur résolution implique des temps de calcul très longs malgré l'utilisation d'importantes ressources informatiques.Dans cette thèse, on s'intéresse à la résolution de problèmes complexes couplant écoulements et transferts thermiques. Les problèmes physiques étant fortement anisotropes, il est nécessaire d'avoir un maillage avec une résolution très élevée pour obtenir un bon niveau de précision. Cela implique de longs temps de calcul. Ainsi il faut trouver un compromis entre précision et efficacité. Le développement de méthodes d'adaptation en temps et en espace est motivé par la volonté de faire des applications réelles et de limiter les inconvénients inhérents aux méthodes de résolution non adaptatives en terme de précision et d'efficacité. La résolution de problèmes multi-échelles instationnaires sur un maillage uniforme avec un nombre de degrés de liberté limité est souvent incapable de capturer les petites échelles, nécessite des temps de calcul longs et peut aboutir à des résultats incorrects. Ces difficultés ont motivé le développement de méthodes de raffinement local avec une meilleure précision aux endroits adéquats. L'adaptation en temps et en espace peut donc être considérée comme une composante essentielle de ces méthodes.L'approche choisie dans cette thèse consiste en l'utilisation de méthodes éléments finis stabilisées et le développement d'outils d'adaptation espace-temps pour améliorer la précision et l'efficacité des simulations numériques.Le développement de la méthode adaptative est basé sur un estimateur d'erreur sur les arrêtes du maillage afin de localiser les régions du domaine de calcul présentant de forts gradients ainsi que les couches limites. Ensuite une métrique décrivant la taille de maille en chaque noeud dans les différentes directions est calculée. Afin d'améliorer l'efficacité des calculs la construction de cette métrique prend en compte un nombre fixe de noeuds et aboutit à une répartition et une orientation optimale des éléments du maillage. Cette approche est étendue à une formulation espace-temps où les maillages et les pas de temps optimaux sont prédits sur des intervalles de temps en vue de contrôler l'erreur d'interpolation sur la domaine de calcul
Nowadays, with the increase in computational power, numerical modeling has become an intrinsic tool for predicting physical phenomena and developing engineering designs. The modeling of these phenomena poses scientific complexities the resolution of which requires considerable computational resources and long lasting calculations.In this thesis, we are interested in the resolution of complex long time and large scale heat transfer and fluid flow problems. When the physical phenomena exhibit sharp anisotropic features, a good level of accuracy requires a high mesh resolution, hence hindering the efficiency of the simulation. Therefore a compromise between accuracy and efficiency shall be adopted. The development of space and time adaptive adaptation techniques was motivated by the desire to devise realistic configurations and to limit the shortcomings of the traditional non-adaptive resolutions in terms of lack of solution's accuracy and computational efficiency. Indeed, the resolution of unsteady problems with multi-scale features on a prescribed uniform mesh with a limited number of degrees of freedom often fails to capture the fine scale physical features, have excessive computational cost and might produce incorrect results. These difficulties brought forth investigations towards generating meshes with local refinements where higher resolution was needed. Space and time adaptations can thus be regarded as essential ingredients in this recipe.The approach followed in this work consists in applying stabilized finite element methods and the development of space and time adaptive tools to enhance the accuracy and efficiency of the numerical simulations.The derivation process starts with an edge-based error estimation for locating the regions, in the computational domain, presenting sharp gradients, inner and boundary layers. This is followed by the construction of nodal metric tensors that prescribe, at each node in the spatial mesh, mesh sizes and the directions along which these sizes are to be imposed. In order to improve the efficiency of computations, this construction takes into account a fixed number of nodes and generates an optimal distribution and orientation of the mesh elements. The approach is extended to a space-time adaptation framework, whereby optimal meshes and time-step sizes for slabs of time are constructed in the view of controlling the global interpolation error over the computation domain

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Zacharie, Célien. "Modélisation des transferts thermiques instationnaires par modèles paramétriques : application à un four industriel de brasage d’échangeur sous vide." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0264.

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Dans le procédé de fabrication d'échangeurs de chaleur à plaques et ondes brasées chez Fives Cryo (88, France), l'opération de brasage dans un four électrique sous vide consiste à assembler un empilement de pièces en aluminium de plusieurs mètres cubes en portant ce dernier à la température de fusion de la brasure. La maîtrise des transferts de chaleur lors de cette opération est nécessaire afin d'assurer la qualité de production. L'enjeu à terme, pour l'entreprise, est de développer un nouvel outil de simulation basé sur des modèles réduits, adaptables à toutes les topologies d'échangeurs, et de l'implémenter sur le procédé réel pour optimiser le pilotage du four. Dans le cadre de la thèse, on a montré que des modèles paramétriques de type ARX pouvaient reproduire le comportement du système étudié composé du four et de sa charge, sous certaines conditions. Les modèles ARX peuvent être interprétés comme des sous-produits de fonctions de transfert thermiques qui peuvent recalculer des températures en certains points pertinents de la charge : à sa surface et en son centre. Pour vérifier leur identifiabilité, ces lois de comportement ont été étudiées à partir de modélisations numériques du système réalisées à l'aide des logiciels FlexPDE® (1D et 2D) et Simfurnace® (logiciel interne 3D). En parallèle, une caractérisation de la métrologie du procédé a été réalisée. L'évaluation et la maîtrise des erreurs de mesure dans un dispositif sous vide et soumis à de hauts flux radiatifs sont essentielles pour obtenir des mesures fiables des températures en régimes transitoire et stationnaire. La recherche des conditions d'instrumentation garantissant cette fiabilité est un enjeu de premier ordre pour rendre le procédé de brasage reproductible, cette propriété étant requise par ailleurs pour identifier convenablement des fonctions de transfert à partir de données expérimentales et les exploiter par la suite
In the brazed aluminium heat exchanger manufacturing process at Fives Cryo (88, France), the brazing operation in an electric vacuum furnace consists of assembling a stack of aluminum parts of several cubic meters by making it reach the melting temperature of the braze. The control of heat transfer during this operation is necessary to ensure production quality. The long-term challenge for the company is to develop a new simulation tool based on reduced models, adaptable to all heat exchanger geometries, and to implement it on the real process to optimize the control of the furnace. Within the framework of the thesis, it was shown that parametric models ARX can reproduce the behaviour of the studied system composed of the furnace and its load under certain conditions. ARX models can be interpreted as a by-product of heat transfer functions that can recalculate temperatures at relevant points of the load: at its surface and its core. To verify their identifiability, these behavior laws were studied from numerical modeling of the system using FlexPDE® (1D and 2D) and Simfurnace® (internal 3D software). In parallel, a characterization of the process metrology was carried out. The evaluation and control of measurement errors in a device under vacuum and subjected to high radiative fluxes are essential to obtain reliable temperature measurements in transient and stationary states. The research of instrumentation conditions guaranteeing this reliability is a major challenge to make the brazing process reproducible. This property is also required to properly identify transfer functions from experimental data and to exploit them afterwards

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Bourgeois, Thierry. "Couplage du logiciel Phoenics et de la méthode de zones en vue de la modélisation du transfert de chaleur dans des fournaises industrielles /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1988. http://theses.uqac.ca.

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Reis, Walter Luiz da Costa. "Otimização da reciclagem de resíduos siderúrgicos por redução carbotérmica." Universidade Federal de São Carlos, 2008. https://repositorio.ufscar.br/handle/ufscar/663.

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The evolution of the world-wide production of steel in rates superior to 7% per year in the last five years, strongly driven by China, which got off 222,4 millions in 2003 for 489,0 million tons in 20071, leads to a strong increase in the demand of iron ore. Therefore, fine ore price of Carajás for Asia went out from 28,14 in 2003 for 73,20 US$ cents for unity of iron in 2007. An increase of 160%. These facts, when related to the layer exhaustion and the growing environmental pressures on Iron and Steel Plants of the whole world, have been taking to a series of studies to the use of the residues bearers from iron produced in these factories. Up to that time, there has not been consolidated any technology which is technically and economically viable for the recycling of these residues so far. The present work is about the usage of the blast furnace mud, the mill scale and the iron oxide produced in the pickling lines of Companhia Siderúrgica Nacional (CSN) in self reduction pellets shape. It starts the productions in scale laboratorial and industrial after the chemical and physical characterizations from these raw materials. As soon as the most appropriated formulation was defined, the production in experimental scale began. These tests were carried out in the residues palletizing pilot plant, developed by CSN. There were also tests of self reduction and of meltreduction. In the first one, the formation of a metal drop inside a hallow sphere was obtained, and in the second one a metal profit of 99,1%. In sequence, the alternatives were valued for internal recycling of these pellets. The use of the heat contained in the empty hot-metal torpedo-cars for self-reduction showed the most economical route. This technology of recycling was introduced industrially in CSN. Thus, in the present work of doctorate, it was developed an unpublished route for industrial recycling for iron and steel residues, which was technically and economically feasible.
O crescimento da produção mundial de aço bruto em taxas superiores a 7% ao ano nos últimos cinco anos, fortemente impulsionado pela China, que saltou de 222,4 milhões em 2003 para 489,0 milhões de toneladas em 20071, gerou um forte aumento na demanda de minério de ferro. Com isso, o preço do minério fino de Carajás para a Ásia saiu de 28,14 em 2003 para 73,20 US$ cents por unidade de ferro em 2007. Um aumento de 160%. Estes fatos, associados à exaustão das jazidas e as crescentes pressões ambientais sobre as Siderúrgicas de todo o mundo, têm levado a uma série de estudos para o aproveitamento dos resíduos portadores de ferro gerados nestas Usinas. Até então, não se consolidou nenhuma tecnologia viável técnica e economicamente para esta reciclagem. O presente trabalho trata da utilização da lama de alto-forno, da carepa de laminação e do óxido de ferro gerado nas linhas de decapagem da Companhia Siderúrgica Nacional CSN na forma de pelotas auto-redutoras. Após as caracterizações químicas e físicas destas matérias-primas, partiu-se para as produções em escala laboratorial e industrial. Definida laboratorialmente a formulação mais adequada, partiu-se para a produção experimental. Esta foi realizada na planta piloto de pelotização de resíduos, desenvolvida pela CSN. Foram realizados ensaios de auto-redução e de fusão-redução. No primeiro, o resultado foi a formação de uma gota metálica dentro de uma esfera oca e no segundo, um rendimento metálico de 99,1%. Em seqüência, foram avaliadas as alternativas para reciclagem interna destas pelotas. A utilização do calor contido nos carrostorpedo vazios para a auto-redução se mostrou como a rota mais econômica. Esta tecnologia de reciclagem já se encontra implantada industrialmente na CSN. Portanto, no presente trabalho de doutoramento, desenvolveu-se uma rota inédita de reciclagem industrial dos resíduos siderúrgicos portadores de ferro, viável técnica e economicamente.

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Piquemal, Philippe. "Élaboration d'un nouveau matériau isolant phonique et thermique en verre expansé et mise au point d'un procédé utilisant un chauffage diélectrique." Nancy 1, 1988. http://www.theses.fr/1988NAN10203.

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On cherche à fabriquer un matériau en verre expansé (foamglass) ayant une bonne absorption acoustique à l'aide d'un processus d'expansion faisant appel au chauffage mixte diélectrique et infra-rouge. Deux types de matériaux à cellules ouvertes (petites bulles ou grandes bulles) sont conçus au laboratoire. On suit l'absorption aux moyennes et hautes fréquences (microondes). L'apport d'énergie électromagnétique au cours du chauffage infra-rouge favorisé l'expansion du matériau, alors que les microondes sont peu satisfaisantes

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Garrofé, Paulo Henrique Simas. "Uma perspectiva pós-fordista na operação de sistemas elétricos." reponame:Repositório Institucional do FGV, 2004. http://hdl.handle.net/10438/8056.

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This work intends to show, through a case study, that the implementation of a production and work organization model based on process management could be seen through a post-Fordist perspective in the operation of power systems. Large brazilian companies in the power industry have adopted, since their creation, an organizational model based on management rules proposed by Henri Fayol, in a vertical and hierarchical structure fashion. On the other hand, the tasks performed in the control rooms of their Operation Centers follow the schemes established by Frederick Taylor's Scientitic Administration system and the principIes proposed by Henry Ford. Nevertheless, due to changes in the institutional model of the power industry that took place in the mid-nineties and the increasing awareness of society toward its rights along with the workers' urge for the democratization of social relations in their working environment, these power industry companies were driven to seek for fresher styles of management, more suitable for the new cultural, political, social and economic scenario. The System Operation Department in FURNAS decided to embrace, as a new form of production and work organization, a system based on process management, yet respecting the functional structure of the company, thus creating a matrix organizational structure. Notwithstanding, it has been observed that, depending on the implementation form and the adopted management mechanisms, this new system could be seen through a post-Fordist perspective in the operation activity of bulk power systems, typically carried out in Brazil by Fayolist companies, according to a Taylorist-Fordist perspective. To verify the outcome of this implementation, a research was carried out in alI tive Operation Centers of the System Operation Department in FURNAS Centrais Elétricas S.A., having as a key element the following characterization of the post-Fordist paradigm: integrated differentiation of production and work organization under the trajectory of technological innovation toward the democratization of social relations in enterprise-systems. The paper presents the perception both of the evolution in the workers' interpersonal relations and of the managerial actions taken to introduce this new system and shows the occurred changes regarding the democratization of social relations in the Department as well, among other factors which substantiate the research, whose results point to a new form of work and production management where these social relations tend to follow dialogical managerial actions that characterize the post-Fordist perspective.
O objetivo deste trabalho é mostrar através de um estudo de caso que a implantação de um modelo de organização da produção e do trabalho baseado na gestão por processos pode acenar com uma perspectiva pós-fordista para a atividade de operação de sistemas de energia elétrica. As grandes empresas brasileiras do setor de energia elétrica adotaram, desde a sua criação, um modelo organizacional com base nas funções gerenciais propostas por Henri Fayol, sendo estruturadas de forma vertical e hierárquica. Por outro lado, as tarefas realizadas nas salas de controle dos Centros de Operação dessas empresas se processam de acordo com a forma preconizada pelo sistema de Administração Científica de Frederick Taylor e pelos princípios propostos por Henry Ford. Porém, em decorrência da mudança do modelo institucional do setor de energia, ocorrida em meados da década de 90, além da maior conscientização da sociedade a respeito dos seus direitos de cidadania e também da busca dos trabalhadores pela democratização nas relações sociais em seu ambiente de trabalho, as empresas de energia elétrica foram compelidas a buscar novas formas de gestão mais adequadas ao novo cenário cultural, político, social e econômico. Em FURNAS, como nova forma de organização da produção e do trabalho, o Departamento de Operação do Sistema resolveu adotar um sistema baseado na gestão por processos que respeita a estrutura funcional da Empresa, formando, assim, uma estrutura organizacional matricial. Por outro lado, observou-se que, dependendo da forma de implantação e dos mecanismos de gestão adotados, esse novo sistema podia acenar com uma perspectiva pós-fordista para a atividade de operação de sistemas elétricos de grande porte que, tipicamente, no Brasil, é desenvolvida por empresas fayolistas, segundo uma perspectiva taylorista-fordista. Para verificar se essa possibilidade se concretizou foi realizada uma pesquisa que abrangeu os cinco Centros de Operação do Departamento de Operação do Sistema de FURNAS Centrais Elétricas S.A., tomando como elemento-chave a seguinte caracterização do paradigma do pós-fordismo: diferenciação integrada da organização da produção e do trabalho sob a trajetória de inovação tecnológica em direção à ~ democratização das relações sociais nos sistemas-empresa. O trabalho apresenta a percepção da evolução nos relacionamentos interpessoais e a percepção das ações gerenciais empreendidas visando a implantação do novo sistema, bem como também mostra as transformações ocorridas no tocante à democratização das relaçõe~ sociais no Departamento, entre outros fatores que substanciam a pesquisa, cujo resultado aponta para uma nova forma de gestão do trabalho e da produção em que essas relações sociais tendem a ser pautadas por ações gerenciais dialógicas que caracterizam a perspectiva pós-fordista.

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Ntuli, Anthony Cebisa, and 安東尼. "Modelling of heat transfer in industrial furnace walls." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/84532419092604966526.

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碩士
崑山科技大學
機械工程研究所
104
Heat transfer through a multi-layer domain can depend on the individual thermal conductivity of the materials and their layer thickness. Thus to minimize heat flux, the thickness should be increased while choosing a material with low thermal conductivity. The heat flux also depends on the temperature difference between the layer, large temperature differences can lead to high heat flux across the layer. Also it can greatly depend on the contact between the layers, either a perfect contact or a rough surface. Usually, rough layers lead to minimized heat transfer across the domain, that depends on the gas in the gaps of the rough surfaces, contact pressure, hardness of the materials in contact and the mean slope of the rough surfaces. It is known that most gases have very low thermal conductivity. This allows them to be used as an insulator in many industrial and general designs. But as much as it is a good insulator, a gas has a tendency of developing a velocity field, either a laminar flow or turbulent flow, depending on the parameters and conditions. This velocity field can, in turn increase the thermal conductance of the gas, and cause inconsistent temperature and heat flux distribution profiles. This study aims to research and simulate heat transfer in industrial furnace walls. Different structures of walls are studied. A three-layer multi-refractory furnace is considered. Vertical wall, upside wall and bottom walls are studied. At the surfaces, cooling by natural convection can make the surface to be non-isothermal. This is because there are different local heat transfer coefficients along the surface of the vertical or horizontal plate. The effect of natural convection to the temperature distribution and heat flux distribution is studied. Major cases that are observed are adding a layer of a gas between the walls and studying when two of the wall linings are rough surfaces, with a gas inside the gaps of the rough surfaces, contact thermal heat transfer. Air is used for the air gap. The effect of the gas layer thickness to the temperature profile and heat flux profile is studied. Computational Fluid Dynamics software is used to carry out the simulations. The advantages and disadvantages of the study are discussed.

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(5930321), Guangwu Tang. "Modeling of Steel Heating and Melting Processes in Industrial Steelmaking Furnaces." Thesis, 2019.

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Steel heating and melting processes consume the majority of the energy used in advanced short-process steelmaking practices. Economic and environmental pressures from energy consumption drive the research to improve the furnace operation efficiency and energy efficiency. The goal of this research is to utilize computational fluid dynamics (CFD) modeling to provide useful tools and recommendations on the steel heating and melting practices in the steelmaking process. The steel slab reheating process, the steel scrap preheating process and the steel scrap melting process are studied.

A transient three-dimensional (3-D) CFD model was developed to simulate the flow characteristics, combustion process and multi-scale, multi-mode heat transfer inside the reheating furnace. The actual geometry of an operating industrial furnace was used and typical operating conditions were simulated. Specific walking speeds of slabs in production were modeled using a dynamic mesh model which is controlled by a user-defined function (UDF) solved using ANSYS Fluent. Fuel variations at different zones with respect to time were also considered. The model was validated with instrumented slab trials conducted at the SSAB Mobile (Alabama) mill. The temperature field in the furnace and the temperature evolution of a slab predicted by the CFD model are in good agreement with those obtained from the instrumented slab trials. Based on the simulation results, the slab reheating process and the temperature uniformity of a slab at discharge were able to be properly evaluated. In addition, a comprehensive two-dimensional (2-D) numerical heat transfer model for slab reheating in a walking beam furnace was developed using the finite difference method. An in-house code was developed. The model is capable of predicting slab temperature evolution during a reheating process based on real time furnace conditions and steel physical properties. The model was validated by using mill instrumented slab trials and production data. The results show that the temperature evolution predicted by the model is in good agreement with that measured by the thermocouples embedded in the instrumented slab. Compared with 3-D CFD simulation of a reheating process, this 2-D heat transfer model used for predicting slab temperature evolution requires less computing power and can provide results in a few seconds. A graphical user interface was also developed to facilitate the input and output process. This is a very convenient and user-friendly tool which can be used easily by mill metallurgists in troubleshooting and process optimization.

CFD models for steel scrap preheating and melting processes by the combined effects of the heat source from both oxy-fuel combustion and electric arc were also developed. The oxy-fuel burners firing natural gas (NG) are widely used in EAF operation during the scrap preheating and melting stages. In order to understand the role of oxy-fuel combustion and potentially increase the energy input from NG while decreasing the electricity consumption, numerical simulation of scrap preheating by oxy-fuel combustion in an EAF was firstly conducted. A 3-D CFD model was developed with detailed consideration of gas flow, oxy-fuel combustion, heat transfer between gas and solid scrap and scrap oxidation. The model was validated by a small-scale experimental study and applied onto a real-scale EAF.

Scrap melting in bath is comprehensively studied with a CFD model developed to simulate the melting in bath process under given operating conditions. Two sub-models were developed for model integration: steel melting model and coherent jet model. The multiphase volume of fluid (VOF) model and the enthalpy-porosity technique are applied to describe the steel melting process. The coherent jet model calculates the gas jet momentum and is integrated into the flow model to calculate its effect on the fluid flow in the bath. The electric arc was treated as a heat flux to represent the heat transfer from the electric arc during the melting process. Model validations were conducted for each sub-model to ensure their accuracy. Parametric studies were also carried out to obtain useful information for real practice.

Overall, the CFD models developed in this research work have demonstrated value in improving energy efficiency in the energy-intensive steelmaking processes. The developed CFD models also provide insights for better understanding of the multi-physics processes.

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