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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.
101

A case study of factors impacting on marketing of South African fish oil in the animal feed market

Stefanus, Titania Vaida January 2002 (has links)
Thesis (MTech (Business Administration))--Peninsula Technikon, Cape Town, 2002 / The growing and declining demand of the different fish oil application markets. The price of heavy furnace oil compared to fish oil selling price. (Heavy furnace oil is used to generate energy) . The research also investigated the impact of low price fish oil substitutes on the South African fish oil producers. The most important substitute in the current South African majority market, the animal feed market, is vegetable oils. The research finding is that the South African fish oil producers must follow the vegetable oil selling price trend. The most important finding of the research is the high priority the fish oil quality achieves in all the fish oil market segments. The South African domestic market is limited in that it is only the animal feed market and the refinery. export market. The alternative market to sell to is the However, the international fish oil market perceives the South African fish oil to be of low quality. A mindset regarding the importance of fish oil quality has to start at the South African fish oil producers. It is vital that the South African fish oil producers institute quality systems to improve their fish oil quality. The South African fish oil producers must gear themselves to become globally competitive.
102

Remo??o de fenol de efluentes aquosos utilizando flocula??o i?nica

Cavalcante, Paula Romyne de Morais 29 January 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-22T15:37:57Z No. of bitstreams: 1 PaulaRomyneDeMoraisCavalcante_DISSERT.pdf: 1897900 bytes, checksum: 10e345e2f054e35a8e9acff79b0689c5 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-27T23:17:33Z (GMT) No. of bitstreams: 1 PaulaRomyneDeMoraisCavalcante_DISSERT.pdf: 1897900 bytes, checksum: 10e345e2f054e35a8e9acff79b0689c5 (MD5) / Made available in DSpace on 2016-07-27T23:17:33Z (GMT). No. of bitstreams: 1 PaulaRomyneDeMoraisCavalcante_DISSERT.pdf: 1897900 bytes, checksum: 10e345e2f054e35a8e9acff79b0689c5 (MD5) Previous issue date: 2016-01-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A explora??o de petr?leo ? uma das mais importantes atividades industriais da sociedade moderna e apesar de seus derivados apresentarem in?meras aplica??es em rela??o aos processos industriais, existem muitos subprodutos indesej?veis durante esse processo, um deles ? a ?gua separada do petr?leo, denominada ?gua de produ??o, que ? constitu?da por poluentes de dif?cil degrada??o. Al?m disso, o elevado volume de ?gua gerado torna seu tratamento um grande problema para as ind?strias petrol?feras. Dentre os principais contaminantes desses efluentes est?o o fenol e seus derivados, subst?ncias de dif?cil degrada??o natural que devido ao poder t?xico, devem ser removidos por um processo de tratamento antes de sua disposi??o final. Com o intuito de viabilizar a remo??o de fenol em ?guas residuais da ind?stria petrol?fera foi desenvolvido um sistema de extra??o por flocula??o i?nica com tensoativo. A flocula??o i?nica baseia-se na rea??o de tensoativo carboxilado com c?lcio originando um tensoativo insol?vel, que sob agita??o agrega-se formando flocos capazes de atrair a mat?ria org?nica atrav?s da adsor??o. No presente trabalho, utilizou-se sab?o base como tensoativo na flocula??o i?nica e avaliou-se a efici?ncia do processo pela influ?ncia dos seguintes par?metros: concentra??o de tensoativo, fenol, c?lcio e eletr?litos, velocidade de agita??o, tempo de repouso, temperatura e pH. A flocula??o do tensoativo se deu no pr?prio efluente (concentra??o inicial de fenol = 100 ppm,) e a efici?ncia de remo??o alcan?ou 65% de remo??o, utilizando concentra??es de tensoativo e c?lcio de 1300 e 975 ppm, respectivamente em T = 35 ?C, pH = 9,7, velocidade de agita??o = 100 rpm e tempo de contato de 5 minutos. A perman?ncia dos flocos em meio aquoso promove a dessor??o do fenol da superf?cie do floco para a solu??o, atingindo 90% de dessor??o em um tempo de 150 minutos, e o estudo da cin?tica de dessor??o mostrou que o modelo de Lagergren de pseudo-primeira ordem foi adequado para descrever a dessor??o do fenol. Estes resultados mostram que o processo avaliado pode configurar uma nova alternativa para o tratamento no que se refere a remo??o de fenol de efluentes aquosos da ind?stria de petr?leo. / Oil exploration is one of the most important industrial activities of modern society. Despite its derivatives present numerous applications in industrial processes, there are many undesirable by-products during this process, one of them is water separated from oil, called water production, it is constituted by pollutants difficult to degrade. In addition, the high volume of generated water makes its treatment a major problem for oil industries. Among the major contaminants of such effluents are phenol and its derivatives, substances of difficult natural degradation, which due their toxicity must be removed by a treatment process before its final disposal. In order to facilitate the removal of phenol in wastedwater from oil industry, it was developed an extraction system by ionic flocculation with surfactant. The ionic flocculation relies on the reaction of carboxylate surfactant and calcium ?ons, yielding in an insoluble surfactant that under stirring, aggregates forming floc capable of attracting the organic matter by adsorption. In this work was used base soap as ionic surfactant in the flocculation process and evaluated phenol removal efficiency in relation to the following parameters: surfactant concentration, phenol, calcium and electrolytes, stirring speed, contact time, temperature and pH. The flocculation of the surfactant occurred in the effluent (initial phenol concentration = 100 ppm) reaching 65% of phenol removal to concentrations of 1300 ppm and calcium of 1000 ppm, respectively, at T = 35 ?C, pH = 9.7, stirring rate = 100 rpm and contact time of 5 minutes. The permanence of the flocs in an aqueous medium promotes desorption of the phenol from the flake surface to the solution, reaching 90% of desorption at a time of 150 minutes, and the study of desorption kinetics showed that Lagergren model of pseudo-first order was adequate to describe the phenol desorption. These results shows that the process may configure a new alternative of treatment in regard the removal of phenol of aqueous effluent of oil industry.
103

Transformações territoriais em Macaé decorrentes das atividades petrolíferas / Territorial implications in Macae resulting from oil activities

Nelson José Zampier Bonin 14 May 2015 (has links)
A pesquisa tem por objetivo investigar as implicações da atividade petrolífera em Macaé-RJ. A instalação de empresas e a geração de empregos modificou a dinâmica populacional do município e região, atraindo migrantes e aumentando a urbanização e sua orientação. O aumento financeiro do orçamento municipal a partir das atividades petrolíferas reestruturou a economia, que antes era baseada nas atividades sucroalcooleira, agropecuária, pesca e comércio, para atividades industriais e prestação de serviços, comércio, turismo de negócios. Essas mudanças tornaram o município dependente da atividade petrolífera. As transformações ocorreram não apenas no distrito sede de Macaé, mas também nos outros distritos, que tiveram um aumento populacional, diminuição da atividade agrícola, intensificação das relações campo-cidade. A potencialidade turística da região serrana de Macaé é grande, mas pouco aproveitada, exceto no Sana. A pesquisa analisa essa potencialidade como forma de fortalecimento do rural. O trabalho é apresentado a partir de análise bibliográfica e trabalho de campo. Por fim, a dissertação considera que as implicações da atividade petrolífera em Macaé atingiram primeiramente e intensamente o distrito sede, expandindo-se também para os outros distritos e sua área rural, provocando transformações no setor agrário em direção a um novo rural ou de urbanidades no rural / This research aims to investigate the implications of oil activity in Macaé-RJ. The installation of companies and job creation modified the population dynamics of the city and region, attracting migrants and increasing urbanization and its orientation. The financial increase in the municipal budget from oil activities restructured the economy, which was formerly based on sugarcane activities, agriculture, fishing, trade, into industrial activities and services, trade, business tourism, etc. These changes have made the city dependent on the oil activity. The changes occurred not only in the district headquarters of Macaé, but also in other districts, which had population increase, decrease in agricultural activity, intensification of rural-urban relationship, etc. The tourism potential of the mountain region of Macaé is great, but little exploited, except in Sana. The research analyzes that capability as a means of strengthening rural activity. This work is presented from literature review and fieldwork. Finally, the dissertation considers that the implications of oil activity in Macaé reached first and intensely the district headquarters, expanding also to other districts and their rural area, causing changes in the agricultural sector towards a new rural or "urbanities in rural"
104

Otimização do uso de recursos críticos no desenvolvimento de campos de petróleo offshore. / Optimization of the use of critical resources in the development of offshore fields.

Sérgio Bassi 23 August 2018 (has links)
O presente trabalho aborda a questão da interligação de poços de petróleo às plataformas de produção com a utilização de embarcações do tipo Pipe Laying Support Vessels (PLSVs). O objetivo do estudo é a maximização da curva de produção de óleo no período analisado, o que passa pelo melhor aproveitamento da frota de PLSVs contratada. São consideradas as especificidades da situação como, por exemplo, as restrições técnicas de cada embarcação para as atividades necessárias, a disponibilidade dos PLSVs, materiais para interligação e a já ocorrência da fase precedente, denominada completação. Considerando todo este conjunto de características do problema, desenvolveu-se uma formulação de Programação Linear Inteira Mista com pontos inovadores em relação à literatura, especialmente no que diz respeito ao incremento da curva de produção por conta da operação de poços injetores e ao declínio natural de poços produtores com o passar do tempo. Como os resultados obtidos nos testes da formulação matemática mostraram-se satisfatórios para pequenas instâncias, mas de alta complexidade computacional para um número grande de atividades, foram elaboradas duas versões de uma heurística construtiva adequada para a resolução de problemas de maior porte. Levando em consideração as mesmas características do problema que foram usadas na etapa de formulação matemática, puderam ser elaborados os algoritmos e suas devidas programações computacionais. A partir disso, foram realizados testes de pequeno porte para verificar a robustez dos algoritmos quanto aos seus comportamentos. Por fim, houve a comparação do caso completo, onde foram aplicadas as heurísticas, com o que ocorreu na situação real, tendo o resultado deste presente estudo apresentado um relevante ganho. / This research presents a real case of connection of oil wells in subsea environment to the production platforms with the use of ships of the type PLSV - Pipe Laying Support Vessels. The objective of this study is to maximize the oil production curve in the horizon considered, which is due to the best exploitation of the outsourced fleet. Specificities of the situation are considered like, for example, technical constraints of each vessel for the required activities, the availability of the PLSVs, materials for connection and the end of the previous phase, called completion. Considering all this set of the problem characteristics, it was developed a Mixed-Integer Linear Programming (MILP) formulation with innovative aspects in relation to the literature, especially with respect to the increase of the production curve due to the operation of injector wells and to the natural decline of producer wells during their operation, in the course of time. As the results obtained in the tests of the mathematical formulation were satisfactory for small instances, but with a high computational time for a great number of activities, two suitable constructive heuristics were elaborated for the resolution of larger problems. Numerical experiments were conducted, in small scale, to verify the robustness of the algorithms. Next, the proposed methods were applied to a real case of an oil company and relevant gains were observed.
105

Caracterizações especiais de combustíveis fóssil e renovável / Special characterizations of fossil and renewable fuels

Lopes, Milena Savioli, 1985- 16 August 2018 (has links)
Orientador: Maria Regina Wolf Maciel / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-16T09:42:59Z (GMT). No. of bitstreams: 1 Lopes_MilenaSavioli_M.pdf: 2642176 bytes, checksum: 41aa3694413f6af27a3d7d75233a5cc6 (MD5) Previous issue date: 2010 / Resumo: Atualmente, as técnicas de medição e o desenvolvimento de novos processos e produtos demandam análises cada vez mais sofisticadas, para atender às especificações de mercado e ambientais. A escolha do método de análise, o seu entendimento teórico e a correta metodologia de execução devem ser avaliados adequadamente para que a exatidão dos resultados seja a maior possível. Pesquisas têm sido continuamente realizadas na busca de métodos analíticos confiáveis, cada vez mais rápidos e, na medida do possível, de menores custos. Pretende-se, assim, chamar a atenção para este tipo de abordagem, que garante a qualidade de resultados e formação de recursos humanos em área tecnológica. Neste contexto, o objetivo dessa dissertação de mestrado foi realizar um estudo sobre técnicas de caracterização e análises físico-químicas de propriedades consideradas fundamentais. Uma compilação de equipamentos e sua respectiva teoria foram estudadas a fim de agregar conhecimento. Como matérias-primas, foram escolhidos três produtos dos mais importantes, hoje, como aplicações: petróleo, biodiesel e óleo fúsel. Os resultados mostraram que as técnicas estudadas de DSC e Reômetro necessitam um maior cuidado na realização dos experimentos; cuidados estes que vão desde a operação do equipamento, até mesmo a introdução da amostra. Outras, como o viscosímetro capilar e o titulador volumétrico de Karl Fischer são, consideravelmente, simples, fornecendo resultados rápidos e precisos / Abstract: Currently, measurement techniques and development of new products and processes require increasingly sophisticated analysis, to meet market specifications and environmental issues. The choice of method of analysis, their theoretical understanding and correct implementation methodology should be evaluated properly, so that the accuracy of the results is the highest possible. Research has been conducted continuously in search of reliable analytical methods, increasingly fast and as far as possible to lower costs. The aim is thus to draw attention to this type of approach, which ensures the quality of results and training of human resources in the technological area. In this context, the objective of this dissertation was to conduct a study on characterization techniques and physico-chemical properties to be essential. A compilation of equipment and accompanying theory were studied in order to aggregate knowledge. As raw materials, were chosen three of the most important products today as applications: Petroleum, biodiesel and fusel oil. The results showed that the techniques studied of DSC and Rheometer require greater care in carrying out the experiments, care ranging from those operating the equipment, even the introduction of the sample. Others, like the viscometer capillary and volumetric Karl Fischer titrator are pretty simple, providing fast and accurate results / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química
106

Transesterificação in situ via etanólise do óleo de levedura para a produção de biodiesel / In situ transesterification by ethanolysis of yeast oil for biodiesel production

Reis, Érika Marques, 1987- 23 August 2018 (has links)
Orientadores: Telma Teixeira Franco, Gustavo Paim Valença / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-23T22:38:12Z (GMT). No. of bitstreams: 1 Reis_ErikaMarques_M.pdf: 5864399 bytes, checksum: 2029f038d594a8b5a6f1c34fc59a68f5 (MD5) Previous issue date: 2013 / Resumo: A procura por combustíveis renováveis tem aumentado e o óleo vegetal transesterificado (biodiesel) surge como alternativa mais promissora em relação ao petróleo e seus derivados, superando problemas de matrizes energéticas e ambientais. A obtenção do biodiesel é de interesse estratégico, por sua viabilidade econômica e a fácil adaptação no mercado de combustíveis. As principais matérias-primas do biodiesel são espécies vegetais oleaginosas com diferentes níveis de produtividade e adaptação a cada região do Brasil. Além das plantas oleaginosas, leveduras, fungos e microalgas são capazes de acumular lipídios, desempenhando papel fundamental na substituição de biodiesel oriundo de vegetais. A Agência Nacional de Petróleo (ANP) permitiu a incorporação de 10% de biodiesel ao diesel promovendo grande aumento na demanda de biodiesel. O presente trabalho tem como proposta investigar a transesterificação convencional e in situ da levedura Lipomyces starkeyi por rota etílica na presença de catalisadores (NaOH e H2SO4 ) para obtenção de biodiesel. No presente estudo a concentração mássica de lipídios de L. starkeyi pelo método Bligh & Dyer (51,15% ± 1,48) e o efeito do solvente sobre a extração lipídica por Soxhlet de L. starkeyi (hexano 2,36%, clorofórmio: metanol (44,75%) e etanol (32,76%) e Butt (hexano 26,18%, clorofórmio: metanol (40,81%) e etanol (30,19%) foram estudados. A eficiência da extração está relacionada diretamente com a polaridade do solvente. A composição do óleo foi determinada pela esterificação a ésteres metílicos e analisados por cromatografia gasosa. O óleo de L. starkeyi é composto basicamente por seis ácidos graxos entre 14 e 18 carbonos, com baixo grau de insaturação, característica desejável para a produção de biodiesel. A caracterização do óleo foi determinada por métodos teóricos e experimentais. A determinação de acilgliceróis por cromatografia líquida de alta perfomance por exclusão de tamanho do óleo observou-se que o hexano e clorofórmio: metanol obtiveram maior concentração de triacilglicerídios que o etanol. As transesterificaçoes in situ catálise ácida foi analisada por cromatografia gasosa acoplada a espectrômetro de massas. / Abstract: The demand for renewable fuels has increased and transesterified vegetable oil (biodiesel) emerges as a promising alternative to oil and its derivatives, overcoming problems of energy and environmental matrices. Obtaining biodiesel is of strategic interest for its economic viability and the easy adaptation of the fuel market. The main raw materials of vegetable oil biodiesel are species with different levels of productivity and adaptation to each region of Brazil. In addition to the oil plants, yeasts, microalgae and fungi are able to accumulate lipids, playing a key role in the replacement of biodiesel derived from vegetable. The National Petroleum Agency ( ANP ) has allowed the incorporation of 10 % biodiesel to diesel promoting large increase in demand for biodiesel . This paper aims to investigate the transesterification in situ and conventional yeast Lipomyces starkeyi by ethyl route in the presence of catalysts ( NaOH and H2SO4) to obtain biodiesel . In this study the mass concentration of lipids of L. starkeyi method by Bligh & Dyer ( 51.15% ± 1.48 ) and the effect of solvent on the extraction of lipids by Soxhlet ( 2.36% hexane , chloroform : methanol ( 44.75% ) and ethanol ( 32.76 %) and Butt ( 26.18% hexane , chloroform : methanol ( 40.81 %) and ethanol ( 30,19 % ) were studied the extraction efficiency is directly related to the polarity of the solvent . The oil composition was determined by esterification to methyl esters and analyzed by gas chromatography. The oil L. Starkeyi is basically composed of six fatty acids between 14 and 18 carbons, with a low degree of unsaturation, a desirable characteristic for the production of biodiesel . The characterization of the oil was determined by theoretical and experimental methods. The determination of glycerides by liquid chromatography high performance size exclusion of the oil showed that the hexane and chloroform: methanol showed higher concentration of triacylglycerols that ethanol. The transesterifications in situ acid catalysis was analyzed by gas chromatography- mass spectrometry. / Mestrado / Engenharia de Processos / Mestra em Engenharia Química
107

Challenges facing government revenue from the Nigerian oil industry : a system dynamics approach

Musawa, Idris Abubakar January 2016 (has links)
Extractive industries (including oil, gas and mining) generally afford an opportunity for the host government to generate the revenue to fund sustainable growth and development. It is therefore not surprising for conventional economic theory to suggest this is a readily available revenue source for resource blessed countries. However, contrary to this reasonable expectation, several of these economies were found to be suffering a financial handicap. Nigeria, despite being the largest crude oil producer in Africa and the tenth largest in the world, has so far found realising the full financial benefits of this nature’s gift unattainable. Using both qualitative and quantitative data as well as grounded theory in the analysis of the qualitative data, this research work has been carried out to develop a model of Nigerian oil industry using System Dynamics modelling methodology in order to understand these challenges. Specifically, the research develops an System Dynamics model to capture and quantify the various potential revenue streams to the Nigerian government from the oil (petroleum) industry with the objective of providing an explanatory model of the causal factors and then using the model to construct policy experiments in order to evaluate policies that may optimise these revenues. Findings show that, the development of the model for the Nigerian oil industry was successfully undertaken. The model was used to evaluate two government policy interventions that were aimed at improving government revenue from the industry. Moreover, a range of alternative scenarios which suggested increase of transparency policy, reduction of rate of gas flare and reduction of time taken for repairs of vandalised facilities were used in the model. The relevant system actors in the Nigerian oil industry were impressed with the modelling idea, particularly in its ability to represents all the economic challenges facing the industry, which offered a better understanding of the system they are dealing with. Overall, the model was able to depict some potential policy points thus serving as a decision-making tool.
108

Modelling the economic implications of offshore oil : the case of Hibernia

Plourde, André January 1985 (has links)
The development and production of Canadian offshore petroleum deposits raises three key sets of issues of interest to economists. First are questions relating to the impact of royalties and taxes on producer decisions, and hence on the level and efficiency of resource taxation. Other issues concern the impacts on the overall economy during both the construction and production phases. A third set of issues relates to the distribution of powers and resource revenues between federal and provincial governments, including the links between provincial resource revenues and equalization payments. This thesis develops a numerically tractable economic model designed to examine these issues. At the model's core is a one-to-one relationship between development plans and production profiles. This property is exploited in simulating the behaviour of a price-taking, net-present-value-maximizing producer under conditions of certainty. The model is linked with a macroeconometric model of the Canadian economy to study the potential consequences of Hibernia, a petroleum deposit located in the Eastern Canadian offshore region. This deposit was chosen for analysis because its size, location and low costs (relative to current world oil prices) combine to raise all of the issues listed above. In most cases studied, producer responses to government policies result in the dissipation of less than five percent of the deposit's net present value to society. Although cases are identified where these responses have more serious consequences, the resulting dissipation of potential net benefits never exceeds 15 percent. The extension of specific forms of royalty and tax relief to the producer generally reduces the distortionary effects of government policies. The simulated exploitation of Hibernia induces small but sympathetic changes in most macroeconomic variables. The net crowding-out effects on other industries are shown to be relatively small, and to be more prevalent during the construction period. The results suggest that the larger share of the net benefits accruing to governments flows to the provincial treasury under three of the revenue-sharing systems modelled. However, Newfoundland and Labrador would lose a substantial portion of its Hibernia revenues under all of the equalization systems modelled. / Arts, Faculty of / Vancouver School of Economics / Graduate
109

A History of the Labor Movement in the Oil Industry

Mullennix, Grady L. January 1942 (has links)
This is a study of the labor movement in the oil industry from an historical approach.
110

Centralized Purchasing Arrangements in a Selected Group of Oil Companies in the Southwest

Strong, Jerry C. January 1951 (has links)
The purpose of the study is threefold: (1) to make a survey of the type of purchasing organizations used by a selected number of oil companies operating in the Southwest, (2) to determine the extent or degree of centralized purchasing used by these firms, and (3) to evaluate briefly the organizational arrangements found in light of accepted principles.

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