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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Precipitações criticas, planejamento e gerenciamento das drenagens superficiais utilizando sistemas de informações geograficas : Refinaria Presidente Bernardes - Cubatão (RPBC) / Critical rains, planning and run-off management using geografic information system on Presidente Bernardes - Cubatão Refinery (RPBC)

Palini, Rita Cristina Cantoni, 1970- 14 August 2018 (has links)
Orientador: Antonio Carlos Zuffo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-14T19:47:45Z (GMT). No. of bitstreams: 1 Palini_RitaCristinaCantoni_M.pdf: 11804088 bytes, checksum: dc5f9467b8338cf5b9ace68f5d00d76a (MD5) Previous issue date: 2008 / Resumo: O aumento das intensidades de precipitação verificado nas últimas décadas tem solicitado mais os itens que compõem os sistemas de drenagem, mostrando a deficiência de alguns projetos de décadas passadas. Aliado a isto, a sociedade tem a necessidade premente de conservação dos recursos hídricos, por causa da escassez de água. Numa refinaria de petróleo este assunto é particularmente importante por causa dos grandes volumes de água utilizados e consumidos no processo industrial, assim como também por causa das grandes dimensões das áreas de processo e de estoque de matéria-prima e produtos acabados, que têm potenciais riscos ambientais associados (óleo cru, naftas, benzeno, "slop", enxofre). Quando a água precipita sobre estas áreas gera diferentes tipos de escoamentos, que podem ser simplesmente escoamento superficial livre (água pluvial), se livres de contaminação proveniente da área industrial, ou efluentes que devem ser tratados, caso venham a contaminar-se em sítios específicos dessas grandes áreas industriais. Neste trabalho pretende-se reunir os conceitos de hidrologia e de precipitações intensas, assim como os conceitos relacionados à produção do escoamento limpo ou efluente contaminado e aplicá-los aos elementos reais da Refinaria Presidente Bernardes (RPBC) em um Sistema de Informação Geográfica - SIG. Desta forma, constrói-se a análise-diagnóstico do problema considerando toda a dinâmica complexidade ambiental, econômica e legal que envolve a planta industrial na drenagem das suas águas. / Abstract: The increase on the rains intensity veryfied on last decades has requested the conveyances over than their capacity, showing deficiencies on old designed systems. At the same time, society has the crying need of water resources conservation, justified by the water's scarcity. In an oil refinery this subject is particularly important because of the great amounts of water that are used and consumed into the industrial process, and also because of the great dimensions of the process and stock of raw material and products areas, which has substances with great environmental risks associated (crude oil, naftas, benzene, slop, sulphur). When the water falls over these areas creates differentflows, that may become storm water flow, when free from the refinery contamination, or may become polluted effluents that must be treated, when contamined in specific industrial area sites. This work intends to join the concepts of hydrology and rain intensity, and also the concepts related to the clean and contamined discharge rate that are produced into the industrial plant and aply them to the Refinery Presidente Bernardes - Cubatão, into a Geographic Information System Database (GIS). By this way, it builds analysis-diagnosis of the problem considering the whole environmental, economics and legal complexity dynamics that involves the water drainage into the industrial plant. / Mestrado / Recursos Hidricos / Mestre em Engenharia Civil
32

Quantificação e redução de emissões de gases de efeito estufa em uma refinaria de petroleo / Quantification and reduction of greenhouse gas emissions in an oil refinery

Chan, Wai Nam, 1964- 12 December 2006 (has links)
Orientador: Arnaldo Cesar da Silva Walter / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-07T23:03:25Z (GMT). No. of bitstreams: 1 Chan_WaiNam_M.pdf: 1006705 bytes, checksum: 9353fc6b1ce1205a679d574738b25bfe (MD5) Previous issue date: 2006 / Resumo: Queima de combustíveis fósseis é a principal contribuição humana para o aquecimento global. Neste trabalho foram investigadas oportunidades de redução das emissões de gases de efeito estufa (GEE) para uma refinaria brasileira de petróleo, através das seguintes etapas: levantamento das estratégias de enfrentamento do problema adotadas por algumas empresas; seleção de uma metodologia de estimativa de emissões de GEE para companhias de óleo e gás; elaboração do inventário da refinaria nacional através do programa aplicativo SANGEA; e proposição de opções para gestão das emissões de GEE dessa refinaria. Combustão e práticas de flaring e venting são os maiores contribuintes das emissões de GEE da cadeia produtiva. Quatro opções de mitigação estão sendo exploradas pelas empresas: aumento da eficiência energética, redução de flaring e venting, mudança para fontes energéticas menos intensivas em carbono e seqüestro de carbono. Neste estudo foi mostrado que o SANGEA é uma ferramenta de estimativa adequada, pois a emissão total de GEE obtida apresentou uma diferença de 1% em relação ao valor estimado pela Petrobrás. Melhoria da eficiência energética é a principal oportunidade de redução de emissões. Para a refinaria estudada foram descritos futuros projetos da área energética que apresentaram um potencial de emissão evitada de 270.000 t CO2 /ano. Por outro lado, a instalação de novas unidades para adequação dos teores de enxofre da gasolina e do diesel resultará na emissão adicional de 208.000 t CO2 /ano. Portanto, o sucesso dos esforços para economizar energia pode ser anulado pelas exigências ambientais para adequação da qualidade dos produtos. Isto ressalta a necessidade dos formuladores de política estabelecer um balanço entre as novas exigências para combustíveis (com impactos locais) e a política de abatimento de CO2 (com impactos globais) / Abstract: Fossil fuel burning is the main human contribution to global warming. In this study, opportunities for reducing greenhouse gas (GHG) emissions were investigated for a Brazilian oil refinery, according to the following steps: survey of climate change strategies adopted by some companies; selection of a methodology for calculating GHG emissions for the petroleum industry; development of an inventory for a national oil refinery by applying SANGEA software; and proposal of options for managing GHG emissions in this refinery. Combustion, flaring and venting are the largest contributors to GHG emissions in the production chain. Four mitigation options are being explored by companies: increasing energy efficiency, flaring and venting reduction, switching to less carbon-intensive sources of energy and carbon sequestration. It was demonstrated that SANGEA is a suitable estimation tool since the calculated total GHG emission showed 1% difference compared to Petrobras estimated value. Energy efficiency improvement is the main opportunity to reduce emissions. For the case study refinery future energy saving opportunities were described and their avoided emission estimation is 270,000 metric tonnes per year of CO2. On the other hand, new process units are required to comply with the gasoline and diesel stricter sulfur specifications, producing an additional emission of 208,000 metric tones per year of CO2. Thus, the successful energy saving efforts can be nullified by environmental requirements for fuel quality. This underlines the need for policy makers to strike a balance between new fuel requirements (with local impacts) and CO2 abatement policy (with global impacts) / Mestrado / Energia, Sociedade e Meio Ambiente / Mestre em Engenharia Mecânica
33

A critique of the use of real option valuation to evaluate an oil industry refining project

Oosthuizen, J. F. (Jan Francois) 12 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2005. / ENGLISH ABSTRACT: The oil industry is under pressure to select refinery projects that will provide higher and more predictable returns. In the past Discounted Cash Flow (DCF) techniques have been used to choose between refinery project alternatives. One of the problems with DCF techniques is that they ignore management flexibility when evaluating projects that contain embedded options. Real Option Valuation (ROV) is an approach that takes management flexibility into account and places a value on this flexibility. ROV has been used extensively by the oil industry for the evaluation of oil and gas reserves. The aim of this study is to determine the extent to which the use of ROV will improve the decision making process when evaluating a refining project containing embedded options as well as to determine the most appropriate option valuation method for refining projects. This was done by evaluating a refining project using both a probabilistic DCF approach and the various option pricing models and comparing the results. It was concluded that ROV will improve the decision making process when evaluating refining projects containing embedded options. The most appropriate option pricing method for refining projects was found to be the simulation approach since simulation is already being used by refineries to perform probabilistic DCF analysis. It is not recommended that ROV should be blindly applied to all refining projects containing embedded options. The use of ROV should be limited to larger refining projects for which probabilistic cash flows have been developed and the extent of the ROV analysis required should be determined by a careful review of the net present value (NPV) cumulative probability curves. / AFRIKAANSE OPSOMMING: Die olie industrie is onder druk geplaas om projekte te kies met 'n hoër opbrengs op kapitaal en 'n opbrengs wat meer voorspelbaar is. In die verlede is slegs die Verdiskonteerde Kontant Vloei (VKV) metode gebruik om projekte te selekteer vir die raffinadery. Een van die onderliggende tekortkominge met die gebruik van die VKV metode is dat verskillende bestuursopsies in terme van alternatiewe met ingeboude opsies, nie voldoende ondersoek word nie. Reële Opsie Waardasie (ROW) is 'n metode wat bestuursopsies in ag neem deur 'n waarde te plaas op elke beskikbare bestuursopsie. ROW het wye toepassings in die olie industrie vir die evaluasie van gas en olie reserves. Die doel van hierdie studie is om te bepaal tot watter mate die gebruik van ROW die besluitnemingsproses sal verbeter in terme van die evaluasie van projekte met ingeboude opsies vir raffinaderye en watter opsiewaardasie metode die mees geskikte is vir sulke projekte. 'n Raffinadery projek is evalueer deur beide KV en verskeie opsie-prysbepalingsmetodes te gebruik en die resultate is vergelyk. Die resultate van die studie het bewys dat die ROW metode die besluitnemingsproses verbeter. Die studie het gewys dat die mees geskikte opsie-waardasie metode vir projekte in the raffinadery die simulasie benadering is omdat simulasie alreeds vir probalisties VKV ontleding gebruik word. 'n Verdere aanbeveling is dat die ROW metode nie blindelings gevolg moet word vir alle projekte met ingeboude opsies nie. Die gebruik van ROW moet beperk word tot groter projekte waarvoor probabilistiese kontantvloei alreeds ontwikkel is. Die mate van ROW ontleding moet bepaal word deur 'n noukeurige ondersoek te doen van die kumulatiewe netto huidige waarde-waarskynlikheidskurwe.
34

Study of Catalyst Particle Emissions From a Fluidized Catalytic Cracker Unit

Whitcombe, Joshua Matthew, n/a January 2003 (has links)
The control of particle emissions from an oil refinery is often difficult, due to changing operational conditions and the limited range of available treatment options. Excessive particle emissions have often been attributed start up problems with Fluidized Catalytic Cracker Units (FCCU) and little information is available regarding the exact composition and nature of these excessive emissions. Due to the complex nature of a FCCU, it has in the past been difficult to identify and control emissions, without the use of expensive end of pipe technologies. An Australian Oil Refinery, concerned with their catalyst emissions, sponsored this study of FCCU particle emissions. Due to the industrial nature of the project, a holistic approach to the management of emissions was taken, instead of a detailed investigation of a single issue. By looking at the broader range of issues, practical and useful outcomes can be achieved for the refinery. Initially, detailed emissions samplings were conducted to investigate the degree of particle emissions under start up conditions. Stack emissions were collected during a standard start up, and analysed to determine the particle size distribution and metal concentration of the emitted material. Three distinct stages of emissions were discovered, initially a high concentration of larger particles, followed by a peak in the very fine particles and finally a reduction of particle emissions to a more steady or normal operational state. The variation in particle emissions was caused by operational conditions, hardware design and catalyst characteristics. Fluctuations in the gas velocity through the system altered the ability of the cyclones to collect catalyst material. Also, the low bed level allowed air bypass to occur more readily, contributing to the increased emissions levels seen during the initial stage of the start up. Reduced fluidity characteristics of the circulating catalyst also affected the diplegs operations, altering the collection efficiency of the cyclone. During the loading of catalyst into the system, abraded material was quickly lost due to its particle size, contributing to fine particle emissions levels. More importantly, thermal fracturing of catalyst particles occurred when the cold catalyst was fed into the hot regenerator. Catalyst particles split causing the generation of large amounts of fine particle material, which is easily lost from the system. This loading of catalyst directly linked to the period of high concentration of fine particles in the emissions stream. It was found that metals, and in particular iron, calcium and silicon form a thick layer on the outside of the catalyst, with large irregular shaped metal ridges, forming along the surface of the particle. These ridges reduce the fluidity of the catalyst, leading to potential disruptions in the regenerator. In addition to this, the metal rich ridges are preferentially removed via attrition, causing metal rich material to be emitted into the atmosphere. To overcome these high particle emissions rates from the FCCU the refinery should only use calcinated catalyst to reduce the influence of thermal process and particle fracture and generation. Although the calcinated catalyst can fracture when added to the system, it is far less than that obtained with uncalicinated catalyst. To further reduce the risk of particle fracture due to thermal stresses the refinery should consider reducing the temperature gradients between the hot and cold catalyst. Due to the economics involved with the regenerator, possible pre-warming of catalyst before addition into system is the preferred option. This pre-heating of catalyst should also incorporate a controlled attrition stage to help remove the build up of metals on the surface of the particles whilst allowing this material to be collected before it can be released into the atmosphere. The remove of the metal crust will also improve the fluidity of the system and reduce the chance of catalyst blockages occurring. Finally, modelling of the system has shown that control of key parameters such as particle size and gas velocity are essential to the management of air emissions. The refinery should look at adjusting start up procedures to remove fluctuations in these key parameters. Also the refinery should be careful in using correlation found in the literature to predicted operational conditions in the system as these correlations are misleading when used under industrial situations.
35

Otimização energetica de redes de trocadores de calor industriais : aplicações em engenharias de petroleo, alimentos e quimica

Rossi, Luciano Fernando dos Santos 29 May 1995 (has links)
Orientador: Antonio Carlos Bannwart / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-07-20T08:34:29Z (GMT). No. of bitstreams: 1 Rossi_LucianoFernandodosSantos_D.pdf: 31189486 bytes, checksum: b5668903a52a4adff00b0520804c237d (MD5) Previous issue date: 1995 / Resumo: Este estudo teve como objetivo a análise de processos industriais, os mais abrangentes possíveis, visando sua otimização do ponto de vista energético-econômico. Neste intento, buscou-se apresentar não apenas um único ponto de otimalidade, mas um conjunto de opções que permita a um decisor escolher a situação mais conveniente. No desenvolvimento deste estudo foram utilizados um conjunto de Métodos de Otimização, dentre os quais podem ser destacados a Metodologia Pinch de Recuperação de Energia, baseada em uma redistribuição de potenciais térmicos dentro do processo analisado, e os Métodos originários da Programação Matemática, em especial a Programação Linear. Analisou-se em profundidade o caso, relativo à lndúsrtria de refino de Petróleo, de uma etapa de Craqueamento Catalítico da Refinaria de Paulínia, da PETROBRÁS. Entretanto, o conjunto de procedimentos aplicados neste trabalho mostrou-se eficiente quando da análise de outros segmentos industriais, em particular das lndústrias Química, de Alimentos e Petroquímica, como apresentado no decorrer deste trabalho. Este estudo mostra que é perfeitamente possível fazer-se uma análise energética e uma avaliação econômica de sua implantação, de uma maneira muito satisfatória e rápida / Abstract: This work deals with the industrial process analysis, includingvarious types and sizes, looking for their optimization fiom the economic and energetic point of view. Not only a single point of optimality was searched but a set of options which could permit to a decision maker to choose the best situation in each case. ln the development of this study were utilized a set of Optimization Methods, among which it can be mentioned the "Pinch Point Methodology" to heat recovery in networks, which is based in a redistribution of the thermal potentials of the process analyzed, and the methods originated tfom the Mathematics Programming, in special the Linear Programming. A deep analysiswas made on the case relative to an oil refinery.More precisely a part ofthe catalytic cracking of the Paulinia's Oil Refinery of PETROBRAS. The set of procedures applied in this work, it can be shown efficient when the analysis is applied to other industrial branches, in particular in the Chemistry, Food and Petrochemistry industries, as shown in throughout this work. This study shows that is possible to make an energetic analysis and an economic cost evaluation on the implementationof a process, in a fast and sactisfatory manner / Doutorado / Termica e Fluidos / Doutor em Engenharia Mecânica
36

Investigation into the economic feasibility of the continued existence of the PetroSA Mossel Bay refinery

McGregor, James Royston 12 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2005. / ENGLISH ABSTRACT: South Africa's main requirements for power are in the form of electricity and liquid fuels The country's electricity is generated mainly from coal while the liquid fuels requirement is mainly from crude oil. Both coal and crude oil use are coming under increasing pressure locally because of pollution and accompanying environmental awareness. Internationally both energy sources are also increasingly being abandoned as preferred energy sources, in first world countries, in favour of cleaner energy sources.ln view of these developments in the macro environment South Africa's gas to liquids refinery built in the early 1990's seems a well placed past investment ahead of its time. This study project looks at the economic feasibility of the continued existence of the PetroSA gas to liquid plant in Mossel Bay.The study looks at South Africa as well as Southern Africa's energy resources , the effect of changing legislation on the future use of energy resources and the economics of the Mossel Bay facility. The study finds that South Africa's abundance of coal reserves, its lack of oil and gas reserves and the slow pace of environmental legislation delivery means that gas is unlikely to become a major source of energy in South Africa.The Mossel Bay gas to liquids plant is profitable but its high fixed costs and certain growth of this cost component means that the continued feasibility of operations is dependant on favourable movements in the exchange rate and oil price. To answer the question about whether to continue operating or close down the analysis found that although although early closure would provide a return of more than 15 percent it would be even more viable financially to make an investment for more gas and continue operations.The main reason for the better than average projected returns is the high oil price .The decision to close down the Mossel Bay plant is not likely to be based on financial considerations alone. The recommendation is thus to continue operations untill 2016.The investment required to secure more gas would , even in the worst case scenario, provide a satisfactory return on investment. / AFRIKAANSE OPSOMMING: Suid Afrika se energie behoeftes is hoofsaaklik vir elektrisiteit en brandstof. Die meerderheid van die land se elektristeit word deur middel van steenkool opgewek terwyl ru-olie gebruik word om brandstof te vervaardig. Beide steenkool en ru-olie word al hoe meer onder druk geplaas as gevolg van besoedeling en 'n meer omgewing bewuste publiek. Op internasionale vlak , in eerste wereld lande word die gebruik van steenkool en ru-olie al hoe meer afgeskaf ten gunsle van skoner kragbronne. In die lig van hierdie verwikkeling in die makro omgewing mag dit op die oog af Iyk of PetroSA se gas na vloeistof aanleg in Mosselbaai, wat reeds in die vroee 1990's gebou is, as 'n goeie destydse strategiese belegging voorkom. Hierdie studie projek ondersoek die ekonomiese lewensvatbaarheid van die voorgesette bestaan van die PetroSA se Mosselbaai gas na vloeislof aanleg. Die studie kyk na Suid-Afrika sowel as die groter Suider Afrika se natuurlike energiebronne, die invloed van verandering in wetgewing op die toekomstige gebruik van energiebronne en die ekonomiese kenmerke van die aanleg in Mosselbaai. Die bevinding van die studie is dat Suid-Afrika se oorvloed van steenkool, sy tekort aan natuurlike gas en die stadige pas waarteen omgewings-wetgewing ontwikkel word, daartoe lei dat gas nie 'n volmatige energiebron in Suid Afrika sal word nie. Die aanleg in Mosselbaai is huidiglik winsgewind maar sy hoe vastekoste en groei hiervan belemmer sy vooruitsigte vanuit 'n finansiele oogpunt. Die winsgewindheid van die aanleg is afhanklik van 'n verswakkende Suid Afrikaanse geldeenheid en verhogende ru-olie pryse. Die vraag onstaan dus of die aanleg moet toemaak en of produksie moet voortgaan. Die ondersoek vind dat alhoewel die sluiting van die aanleg 'n opbrengs van meer as 15 persent sal lewer dit selfs meer finansieel aantreklik is on te belê in meer gas sodat produksie kan voortgaan. Die hoofrede vir die bogemiddelde opbrengs is die hoe oilieprys. Dit is onwaarskynlik dat die oorweging om die Mosselbaaise aanleg sluit suiwer op finansieele oorwegings sal rus. Die aanbeveling is dus om voort te gaan met produksie tot 2016. Die belegging wat nodig is vir meer gas sal selfs onder die mees pessimistiese omstandighede steeds 'n bevredigende opbrengs lewer.
37

Simulação dinâmica, otimização e análise de estratégias de controle da torre de vácuo da unidade de destilação de processos de refino de petróleo / Dynamic simulation, optimization and analysis of control stratefies of the vacuum tower of the distillation unit of petroleum refinery process

Maia, Júlio Pereira, 1978- 23 August 2018 (has links)
Orientador: Rubens Maciel Filho / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-23T11:34:50Z (GMT). No. of bitstreams: 1 Maia_JulioPereira_D.pdf: 8705466 bytes, checksum: e604d7a471ca19eb99492912d431174b (MD5) Previous issue date: 2013 / Resumo: Esta tese apresenta um estudo de estratégias de esquemas de controle em unidades de destilação a vácuo de refinarias de petróleo, com o uso de dados e informações de uma refinaria brasileira, de modo a se desenvolver uma simulação representativa do processo, onde uma diferença global máxima de 5% entre os resultados de simulação e os dados de saída reais foi obtida. A simulação foi executada com alto nível de detalhamento, com cálculos de queda de pressão, dimensionamento de sistemas de bombeamento e uso de internos de coluna comerciais. Uma análise paramétrica foi executada para a verificação das variáveis mais influentes do processo. A simulação em estado estacionário resultante foi então convertida para o regime dinâmico, onde um esquema de controle equivalente ao esquema de controle da planta real foi implementado. Este esquema de controle foi submetido a um conjunto de perturbações usuais ao processo real, produzindo respostas dinâmicas do processo para cada perturbação aplicada. Pela análise das dinâmicas destas respostas e das respostas do sistema em malha aberta, um esquema de controle alternativo foi proposto e verificado da mesma maneira que o esquema de controle equivalente. Malhas de controle específicas para quantificar a qualidade dos produtos, tendo por base o índice ASTM D86 foram inseridas. A comparação entre os dois esquemas de controle por meio das respostas dinâmicas na qualidade dos produtos, considerando como parâmetro o ISE (Integral Squared Error) das malhas de cada esquema para comparação, apresentou uma redução média do erro em 70% na qualidade dos produtos principais / Abstract: A petroleum vacuum distillation unit study on control scheme strategies is developed in this work. Real plant data and information is gathered from a Brazilian Refinery to develop a representative simulation of the process, which had achieved a maximum 5% overall difference from the plant results. The simulation was set to be highly detailed, including pressure drop calculations, pumping system and the use of commercial column internals (packing and plates) in it. A parametric analysis was carried in order to verify the most influent variables in the process, with respect to temperature profiles, product flows and product qualities. The resultant steady state simulation was then converted into dynamic regime, when a control scheme equivalent to the real plant control scheme was implemented. This control scheme was then subjected to a set of common perturbations that occur in the real process, producing the dynamic response of the process to each perturbation applied. By analyzing the dynamics of these responses and the open loop responses, an alternative control scheme is proposed and verified in the same manner the later one was. A specific control loop was proposed to account a petroleum product quality index, such as ASTM D86 95% recovery. The comparison of the control schemes by means of the dynamic responses considering the correlated ISE (integral squared error) of each scheme has shown an average error reduction of 70% in the main products quality / Doutorado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química

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