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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.
11

Recovery of base oil from lithium based waste lubricating grease by solvent-flocculation extraction

26 March 2015 (has links)
M.Tech. (Mechanical Engineering) / This study investigated process development of recovering base oils from waste lithium based lubricating grease using a novel combination of thermal degradation in an aqueous caustic solution and solvent extraction. Lubricating greases consist of a thickening agent dispersed in mineral or synthetic oil, forming a colloidal suspension [1]. Large and increasing volumes of used lubricating oil and grease are produced each year and are considered hazardous wastes. During operation, grease suffers mechanical and thermal degradation [2]. Subsequently, it is regarded as waste and it must be disposed. The waste oil should be collected and recycled not only to prevent the environmental pollution but also to preserve natural resources. Solvent extraction is the preferred method to recycle waste lubricants as it is cost-effective and requires no further purification of the product [3]. The influence of extraction temperature, agitation strength, extraction time, degrading agent concentration, degrading agent-to-grease and solvent-to-sludge mixing ratios on base oil recovery from waste lubricating grease was investigated. This study further optimised the process by studying the influence of various degrading agents (LiOH, NaOH and KOH) and solvents (n-hexane, toluene, heptane, butane, hexanol and acetone) on oil recovery. Oil recovery was enhanced by increase in both extraction temperature, time and agitation speed. The optimum extraction time was found to be 12 minutes. KOH was found to be the optimum degrading agent compared to LiOH and NaOH. Oil recovery also increased from 8.04% to 36.87% with increase in KOH m/m from 5% to 30%. The recovery also increased with an increase of solvent-to-sludge ratio up to 1:6. n-Hexane gave the highest recovery of 74.39% while acetone gave the lowest of 7.43%. A solvent recovery of 82.6% to 88% was obtained through fractional distillation. The study also investigated the differences between virgin and recycled oil using atomic absorption (AA), inductively coupled plasma (ICP) and Fourier transform infrared radiation (FTIR). Rheological studies of waste grease derived oil (WGDO) were also performed. ICP results showed traces of some elements such as Fe, Cu, Si, Ni and Al at a concentration of less than 0.9 mg/L. Oxidation was observed to occur at a band length of 1716 cm-1 while additives were identified at 1670 - 1725 cm-1. The oil viscosity slightly increased with increasing shear rate at temperatures between 60°C and 120°C. The shear rate was varied from 200 to 1000 1/s, with a viscosity convergence at 100°C. A financial economic model was applied to investigate the feasibility of the recycling technology. For 800 kg/day treatment plant, an investment of R 6,031,304.27 is required with a potential return on investment of 40%. Recovery was found to be favourable option compared to landfilling as it offers both economic and environmental benefits.
12

The biodegradation of hydrocarbons using open mixed culture for microbial enhanced oil recovery and bioremediation

Uzukwu, Chukwuemeka January 2017 (has links)
This research has investigated the biodegradation of hydrocarbons particularly n-alkanes using open mixed culture which is relevant for both microbial enhanced oil recovery (MEOR) and the bioremediation of hydrocarbon contaminated soils. Biodegradation of n-C12, C14, C16, C18, C20 and some readily biodegradable substrates (glucose, acetic acid and ethanol) was studied using a respirometric method developed to assess the biodegradability of these compounds. Laboratory batch and semi-continuous experiments were performed in small-scale bioreactors at room temperature and 40oC under various conditions i.e. aerobic, anoxic with nitrate, sulfate reducing and completely anaerobic conditions using two different sources of open mixed microbial cultures obtained from an agricultural site and anaerobic digestion plant. Glucose, acetic acid, ethanol, C12, C14 and C16 were degraded microbially under aerobic batch conditions to nondetectable levels at room temperature and 40oC using the two sources of inoculum whereas C18 and C20 were degraded partially under room temperature and to nondetectable levels at 40oC with the two inocula sources. Under aerobic semi-continuous, glucose and the n-alkane substrate were biodegraded even at low hydraulic retention time (HRT). Under anaerobic conditions, the n-alkanes were utilized by the soil inoculum at room temperature and at 40oC with nitrate as the electron acceptor but no microbial activity was observed under sulfate reducing and completely anaerobic conditions. The open mixed cultures require an initial acclimation period before utilizing the substrates. The acclimation period was significantly shorter under aerobic conditions than anaerobic conditions for the n-alkanes. Acclimation periods of approximately 1-2 days under aerobic conditions was observed for the readily biodegradable substrates and 2 days for glucose under anoxic conditions. The acclimation periods for the nalkanes was between 3-5 days under aerobic conditions and approximately 2 weeks under anoxic conditions. The acclimation period was not affected by the substrate concentration and inoculum type however, for the n-alkanes, the acclimation period was reduced by 1-2days under aerobic conditions at 40oC. The biodegradation of the liquid hydrocarbons was more significant than the solids at room temperature but in general higher temperature increased the degree of biodegradation. The electron acceptor consumption data i.e. dissolved oxygen and nitrate consumption data obtained was mathematically modelled using Monod kinetics to obtain biokinetic parameters. Good fittings between the model solution and the experimental data was obtained. The biokinetic parameters obtained were within the range of values reported in literature. The use of respirometric data for the estimation of biodegradation kinetic parameters can be very reliable. The consistency of the data obtained show that the approach is very reproducible and quality information can be obtained. The results of this study showed that the open mixed microbial cultures from soil and AD inocula contained diverse microorganisms capable of utilizing both liquid and solid n-alkanes at room temperature and 40oC under aerobic and anoxic conditions.
13

Utilização de prototipo nacional de destilador molecular para caracterização de frações pesadas de petroleo / Use of national molecular distiller prototype for characterization of heavy oil fractions

Rocha, Erica Roberta Lovo, 1981- 13 August 2018 (has links)
Orientadores: Maria Regina Wolf Maciel, Cesar Benedito Batistella / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-13T12:03:45Z (GMT). No. of bitstreams: 1 Rocha_EricaRobertaLovo_M.pdf: 1059673 bytes, checksum: 47fe097f3290ef138b0bf4e761b8b464 (MD5) Previous issue date: 2009 / Resumo: A caracterização por meio da curva PEV (Ponto de Ebulição Verdadeiro) é uma das técnicas experimentais mais comuns na determinação das propriedades do petróleo. Esta curva define os rendimentos de diversos derivados de petróleo obtidos em função dos seus pontos de ebulição verdadeiros, fornecendo informações importantes para decisões referentes ao controle dos processos de refinarias e sobre a qualidade do petróleo. Devido ao considerável volume de petróleos pesados e ultrapesados encontrados no Brasil, a extensão da curva PEV a valores acima de 565°C tem sido bastante estudada. O protótipo nacional de destilador molecular de filme descendente, projetado e construído pelo grupo de pesquisa de petróleo do LOPCA/LDPS/FEQ/UNICAMP, é um equipamento de grande potencial, adequado para obtenção da extensão curva PEV e que permite a destilação de produtos de alto peso molecular e termicamente sensíveis, sem degradação dos mesmos. O objetivo geral deste trabalho foi obter experimentalmente cortes e resíduos de dois resíduos nacionais de petróleo, utilizando o protótipo nacional de destilador molecular. A extensão da curva PEV, para os resíduos de petróleo, foi realizada a partir dos dados operacionais do destilador molecular e da correlação DESTMOL, onde as temperaturas operacionais do destilador molecular foram convertidas em pontos de ebulição verdadeiros. Através da destilação molecular foi possível estender a curva PEV até valores próximos a 700 ºC com coerência e continuidade em relação à curva PEV padrão. Além disso, uma quantidade de matéria-prima que estava sendo tratada como resíduo pôde ser recuperada. / Abstract: The characterization through TBP (True Boiling Point) curve is one of the most common experimental techniques for determination of petroleum properties. This curve defines the yield of petroleum products as function of their true boiling points, supplying important information on decisions of refinery process control and on the quality of the produced oil. Due to the considerable volume of heavy and extra heavy oils that has been found in Brazil, the extension of TBP above 565 ºC has been studied. A suitable high potential equipment to obtain the extension of TBP curve is a national falling film molecular distiller prototype that was designed and built up by the oil research group of LOPCA/LDPS/FEQ/UNICAMP, which is appropriated for distillation of products of high molecular weight and thermally sensitive, without their degradation. The aim of this work was to obtain experimentally cuts and residues from two national petroleum fractions, using the national molecular distiller prototype. The extension of TBP curve for petroleum residues fractions was made from the molecular distiller data and the DESTMOL correlation. The operating temperatures of the molecular distiller were converted in the corresponding true boiling points in this correlation. Through molecular distillation process it was possible to extend the TBP curve up to temperatures close to 700 ºC with consistency and continuity related to the standard TBP curve. In addition, a quantity of raw material that was being treated as waste could be recovered. / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química
14

The Biodegredation of Vehicular Waste Petroleum in the Roadside Environment

Johnson, Jesse W. 01 January 1979 (has links) (PDF)
Bacteria from dry and wet roadside environments were examined for the ability to degrade hydrocarbons. The kinds and numbers of bacteria observed were similar to those reported in other petroleum contaminated environments. Surface soils (top 2.5 cm) immediately adjacent to the highway pavement and the sediments of shallow drainage ditches contained the highest concentrations of petroleum degrading bacteria (9.8 x 107 CFU/g). Concentration and species diversity of petroleum degrading bacteria decreased with distance from the highway pavement. Chromatographic analysis of highway stormwater runoff and the soil in close proximity to the highway indicated the presence of complex hydrocarbon mixtures of vehicular origin. The concentrations of chloroform extractable hydrocarbons decreased with distance from the highway pavement. Hydrocarbon degradation rates in the roadside environment were determined by the oxidation of radiolabeled [1-14C] hexadecane. Roadside soil and water samples were incubated under nutrient enriched and in situ environmental conditions. Biodegradation rates in environmental samples enriched with inorganic nutrients were 25-126 fold higher than the in situ rates. The highest in situ rates (92 µg hexadecane g-1 solid h-1) occurred in wet surface solid (top 2.5 cm) immediately adjacent to the highway pavement. The findings of the investigation indicate that the roadside environment under study was a petroleum contaminated ecosystem in which biodegradation of hydrocarbon pollutants was greatly influenced by the design of the roadside drainage systems. Furthermore, petroleum degradation in roadside environments can be enhanced by construction of shallow drainage ditches which support aerobic microbial biodegradation.
15

Copper migration through petroleum-treated soils

Woods, William Eric January 1990 (has links)
The purpose of the project was to determine the effect of various petroleum amendments on the migration rate of Cu. The petroleum amendments used in this research are frequently added to the soil surface in petroleum landfarming. Such petroleum wastes often contain significant amounts of Cu and other metals.Soil columns were amended with citric acid, used crankcase oil and Illinois crude oil. Each amendment was spiked (treated) with three different concentrations of Cu and each treatment was replicated three times. The columns were leached once per week, for ten weeks, with distilled water acidified to pH 4.5 to simulate acid rain. Leachate from the soil columns was analyzed weekly for total Cu. At the end of the ten week period, the soil was analyzed for Cu and TOC content at 7 cm intervals to determine the amount of migration by Cu and the organic amendments, resectively. The soil (a Glynwood silt loam) and the organic amendments were each analyzed for total Cu to determine background levels. The soil was analyzed for pH, TOC, electrical conductivity and soil texture.Analysis of the leachate and soil showed differential migration of Cu through the soil columns. Significant levels of Cu leached in the columns amended with citric acid (as high as 85.3 mg/L) in the first 3 weeks of the study. The Cu content of the leachate from columns amended with crude petroleum were at approximately background levels (5.5 mg/L) as was the leachate from columns amended with crankcase oil (0.2 mg/L). In the later weeks of the research, as the petroleum amendments were broken down by microorganisms, some Cu was chelated to small fragments of the petroleum and leached through the soil columns. Most of the Cu appeared to remain on the surface of the columns, bound to the petroleum amendments. Analysis of the soil, for total Cu content with depth, showed very little Cu accumulation at any depth in the soil column, beyond the soil surface. In most cases Cu levels remained near the background levels found in the control columns.Moderate correlation was found (r2 = .59 for crude oil; r2 = - .54 for crankcase oil; r2 = .85 for citric acid) between Cu levels and TOC levels in the soil columns with depth.From the results of the current study it can be inferred that practices such as petroleum landfarming and land disposal of some hazardous materials may allow for the migration of both the applied petroleum wastes and any metals which may be contained within. / Department of Natural Resources
16

Estudo do processo de craqueamento termico de frações residuais do petroleo / Study of thermal cracking process of petroleum residual fractions

Ramirez Hernandez, Monica Rocio 12 April 2009 (has links)
Orientador: Rubens Maciel Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-14T20:26:29Z (GMT). No. of bitstreams: 1 RamirezHernandez_MonicaRocio_M.pdf: 1944205 bytes, checksum: 84f7c13a59eeccf1f35ecf94dc3a2b79 (MD5) Previous issue date: 2009 / Resumo: A necessidade que a indústria do petróleo tem de suprir a demanda de produtos leves do mercado embora esteja ocorrendo uma diminuição nas reservas de óleos leves e o fato de que a rentabilidade do processo de refino esteja representada na capacidade de obtenção destes derivados leves, faz com que sejam aplicadas tecnologias de "upgrading" dos óleos crus. Diante deste contexto torna-se necessário desenvolver metodologias que permitam simular os fenômenos que ocorrem nestes processos, para deste modo poder avaliar o comportamento das cargas na unidade e desenvolver, a partir destas predições, políticas operacionais com o objetivo de evitar impactos desfavoráveis nos produtos finais, nas unidades de processo e na rentabilidade. Entre as tecnologias de "upgrading" encontram-se desasfaltação com solventes, hidrotratamento, hidroconversão, viscorredução, coqueamento retardado entre outras. No entanto, existe grande preferência na utilização destas duas últimas tecnologias, sendo as mais econômicas e que requerem menor investimento. Com a finalidade de prever situações operacionais foi desenvolvido um simulador, dos processos de coqueamento retardado e viscorredução, que permite predizer os rendimentos de leves gerados no forno tanto em escala piloto como em escala industrial, em função das características da carga e conversão. Além disso, o simulador possibilita o cálculo das constantes cinéticas que descrevem a formação dos destilados, do intermediário (etapa pré-coque), e do coque. A importância de desenvolver estes simuladores para este equipamento se deve ao fato de que os mesmos são encarregados de fornecer as temperaturas necessárias para atingir as reações de craqueamento térmico. Neste processo de aquecimento ocorre a deposição dos asfaltenos, os precursores do coque, os quais ao longo da operação da unidade vão-se depositando sobre os tubos do forno. Com o intuito de controlar o pressionamento gerado pela deposição do coque e a diminuição na transferência de calor é necessário realizar reduções na temperatura de operação, ocasionando menores conversões. Deste modo, é importante definir políticas operacionais que possibilitem bons rendimentos, rentabilidade e tempo de operação da unidade os maiores possíveis. Com os resultados obtidos com os simuladores desenvolvidos pode-se predizer o comportamento das unidades com relação a temperatura de operação, pressionamentos, temperatura de parede, conversão, constantes cinéticas e parâmetros da equação de Arrhenius. Isto possibilita a análise operacional destas unidades de craqueamento quando for alterada a carga e condições operacionais do forno. / Abstract: The obligation that petroleum industry has to supply the market demand for light products, although exists a decrease in light oil reserves and the fact that the refining process profitability is represented by the ability to obtain these lighter products. Against this context is necessary the application of crude oil "upgranding" technologies and methodologies development to simulate the phenomena occurring in these processes, in order to evaluate the feed behavior at the unit and based on predictions, set operational politics with the objective to avoid negative impacts in the final products, unit processes and its profitability. Among the "upgranding" technologies are solvent deasphalting, hydrotreating, hydroconversion, visbreaking, delayed coking and others, however, there is a strong preference in using the last two technologies, being the most economical and requires less investment. With the aim to anticipate operational situations was developed a simulator that can predict the light products yields generated at the furnace, at pilot and industrial units of delayed coking and visbreaking, depending on the feed characteristics and conversion, it also calculates the kinetic constants that describes the rate formation of distillates, intermediate (pre-coke stage), and coke. The importance of developing such simulators for this equipment lies that this is the responsible of providing the temperature necessary to achieve the thermal cracking reactions. In the heating process occurs the asphaltene deposition, the coke precursors, which along the unit operation will be deposited on the furnace tubes. In order to control the pressing generated by the coke and the decrease in heat transfer is needed reductions in operating temperature, causing lower conversions. Thus, is important define operational politics that allows good yields, profitability and run lengths the greatest possible. With the obtained results through the simulators, can be known in advanced the unit behavior as operation temperature, drop pressure, wall temperature, conversion, kinetic constants and parameters of Arrhenius equation, which will facilitate the operational analysis of thermal cracking units when is change for example, feed and operational variables . / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química
17

Valoração dos produtos ultrapesados provenientes da destilação molecular de petróleo / Assessment of petrolem molecular distillation ultra-heavy products

Gordillo Celis, Carlos Alberto 19 August 2018 (has links)
Orientadores: Rubens Maciel Filho, Paula Sbaite Duarte dos Santos / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-19T04:58:43Z (GMT). No. of bitstreams: 1 GordilloCelis_CarlosAlberto_M.pdf: 40097706 bytes, checksum: c60604f84094a693629fd3fbc7ee8c2b (MD5) Previous issue date: 2011 / Resumo: Esta dissertação baseia-se na valoração da corrente de destilado e da corrente de resíduo geradas na destilação molecular (DM) do petróleo as quais são obtidas a partir do resíduo de vácuo (RV) proveniente da unidade de destilação a vácuo (UDV). Primeiramente se separou os asfaltenos da corrente ultrapesada do resíduo da DM (RDM), seguido do tratamento com solvente da corrente do destilado da destilação molecular (DDM). Duas amostras de RDM foram utilizadas como matéria prima na separação de asfaltenos, a primeira delas, o RDM obtido a temperatura do evaporador (TDM) de 340°C e, a segunda, o RDM obtido a TDM=280°C. Os asfaltenos separados chamaram-se de A, B e C. O asfalteno "A", separado do RDM TDM=340°C e os asfaltenos "C" e "B" foram separados do RDM TDM=280°C. A comparação das massas molares e da distribuição de massa molar das amostras separadas foi analisada a partir dos dados obtidos por cromatografia de permeação em gel, onde as massas molares medias variam entre 3737 e 4232 Da. Ressalta-se que foi necessário o desenvolvimento de um metodo analítico apropriado para analise de petróleo e asfaltenos por cromatografia de permeação em gel. As amostras de asfaltenos separados da corrente do RDM foram ainda caracterizadas por espalhamento de luz dinâmico, espectroscopia de infravermelho por transformada de Fourier, microscopia eletrônica de varredura e espectroscopia de energia dispersiva de raios-X. Na segunda metade do trabalho, utilizando-se como matéria prima a corrente de DDM TDM=340°C, comparando-se quatro amostras, duas provenientes do mesmo petróleo e mais duas, provenientes de petróleos diferentes. Partindo dessas correntes foi realizada, a desaromatizarão e desparafinação o óleo DDM em uma montagem experimental de bancada operada a pressão atmosférica e temperaturas de -7 a 80°C. O gasto energético envolvido nesse processamento se resumiu ao aquecimento e resfriamento do reator e do sistema de agitação magnético. Com o uso de solventes como, furfural e metil isobutil cetona (MIBC), a corrente de DDM deu origem a quatro óleos com características de óleos básicos, caracterizados e classificados segundo as viscosidades e índices de viscosidades dos mesmos, classificando-se como óleo básico neutro pesado, brilhante e cilindro pesado, dentro dos grupos API I e V. Assim, a valoração das correntes RDM e DDM fecha o ciclo de um grande projeto, que começou com alimentação do RV na UDM e finalizou com aproveitamento das correntes geradas dando valor agregado a esses produtos / Abstract: This dissertation deals with adding value to the distillate and residual streams of the molecular distillation (MD) of petroleum vacuum residua (PVR), PVR being the residual stream of vacuum distillation unit. First of all, asphaltenes were separated from the molecular distillation ultraheavy stream (MDR), followed by the solvent treatment of the molecular distillation distillate stream (MDD). Two samples of MDR were used as raw material for the asphaltene synthesis: the first was obtained at an evaporator temperature during the MD of 340°C; the second, at TDM=280°C. The molar mass and the molar mass distribution of the two samples were obtained from the gel permation chromatography (GPC) analysis. The asphaltenes with molar masses between 3737 to 4232Da were called "A"; "B" and "C". The asphaltene "A" was separated from MDR 340°C and the asphaltenes "B" and "C" were obtained from MDR 280°C. It's important to highlight that it was necessary to develop an analytic method in order to perform the GPC analysis of the samples. The "A"; "B" e "C" samples were characterized by dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). In the second phase of this work, four samples of MDD 340°C, two of them obtained from one petroleum, and the two remaining obtained from different petroleums, were used as raw materials for the deparaffinization and dearomatization processes. The experimental procedure was carried out at atmospheric pressure and temperatures between -7 to 80°C. The energy requirement for this process was related to the heating and cooling of the reactor and to the agitation system. The MDD treatment with furfural and methyl isobutyl ketone (MIBK) produced four different oils showing basic oil characteristics. The oils were classified according to their viscosity and viscosity index into heavy neutral, bright stock and heavy cylinder stock. Besides, they were classified into the I and V API groups. Thereby, the fact of adding value to the MDR and MDD streams closes a bigger project that started with the use of petroleum vacuum residua as feedstock of the molecular distillation process and ended with the better utilization of the distillation waste oil streams / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química
18

Ecotoxicological studies of shipping operational oily wastes in Hong Kong.

January 1999 (has links)
Lai Ho-yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 104-122). / Abstracts in English and Chinese. / ACKNOWLEDGEMENT --- p.I / ABSTRACT (ENGLISH) --- p.II / ABSTRACT (CHINESE) --- p.IV / TABLE OF CONTENT --- p.VI / LIST OF FIGURES --- p.IX / LIST OF TABLES --- p.V / INTRODUCTION --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Sources of oil pollution --- p.1 / Chapter 1.3 --- Composition of oil --- p.4 / Chapter 1.4 --- Fate of oil in the environment --- p.6 / Chapter 1.5 --- Toxic effect of oil on marine ecosystem --- p.8 / Chapter 1.5.1 --- Acute toxicity --- p.8 / Chapter 1.5.2 --- Chronic toxicity --- p.9 / Chapter 1.5.3 --- Carcinogenicity of oil --- p.11 / Chapter 1.6 --- The origins of ecotoxicology --- p.12 / Chapter 1.7 --- Need for ecotoxicity tests --- p.13 / Chapter 1.8 --- Testings in ecotoxicology --- p.15 / OBJECTIVES --- p.17 / MATERIALS AND METHODS --- p.18 / Chapter 1. --- Collection of oily wastes samples --- p.18 / Chapter 2. --- Preparation of samples --- p.18 / Chapter 2.1 --- Water-soluble fraction --- p.19 / Chapter 2.2 --- Polycyclic aromatic hydrocarbon fraction --- p.20 / Chapter 2.2.1 --- Supercritical fluid extraction --- p.20 / Chapter 2.2.2 --- Silica gel chromatography --- p.22 / Chapter 2.2.3 --- Sample concentration --- p.22 / Chapter 3. --- Chemical analyses of oily wastes --- p.26 / Chapter 3.1 --- Determination of heavy metal concentration in oily waste samples --- p.26 / Chapter 3.1.1 --- Nitric acid-perchloric acid digestion --- p.26 / Chapter 3.1.2 --- Inductively coupled plasma-emission spectrometric analysis --- p.26 / Chapter 3.2 --- Determination of polycyclic aromatic hydrocarbon concentration in oily waste samples --- p.28 / Chapter 3.2.1 --- Determination of polycyclic aromatic hydrocarbon concentration in water- soluble fraction --- p.28 / Chapter a. --- Liquid-liquid extraction --- p.28 / Chapter b. --- Gas chromatography-mass spectrometric analysis of water-soluble fraction --- p.29 / Chapter 3.2.2 --- Determination of polycyclic aromatic hydrocarbon concentration in crude oily waste samples --- p.32 / Chapter a. --- Supercritical fluid extraction and silica gel column chromatography --- p.32 / Chapter b. --- Gas chromatography-mass spectrometric analysis of polycyclic aromatic hydrocarbon fraction --- p.33 / Chapter 4 --- ecotoxicological studies of oily wastes --- p.34 / Chapter 4.1 --- Toxicity tests and sample preparation --- p.34 / Chapter 4.2 --- Ecotoxicological studies of water soluble fraction --- p.34 / Chapter 4.2.1 --- "Growth inhibition test on a marine alga, Chlorella pyrenoidosa CU-2" --- p.34 / Chapter 4.2.2 --- "Survival test on a marine amphipod, Elasmopus rapax" --- p.39 / Chapter 4.2.3 --- "Survival test on a marine fish, Ambassis gymnocephalus" --- p.41 / Chapter 4.2.4 --- Microtox® test --- p.43 / Chapter 4.3. --- Ecotoxicological studies of polycyclic aromatic hydrocarbon fraction --- p.45 / Chapter 4.3.1 --- "Growth inhibition test on a marine alga, Chlorella pyrenoidosa CU-2" --- p.45 / Chapter 4.3.2 --- "Survival test on a amphipod, Parhyale plumulosa" --- p.45 / Chapter 4.3.3 --- "Survival test on the fish, Sparus sarba" --- p.47 / Chapter 4.3.4 --- Microtox® test --- p.49 / Chapter 5. --- Statistical analyses of chemical and ecotoxicological analyses --- p.50 / RESULTS --- p.51 / Chapter 1. --- Chemical analyses of oily wastes --- p.51 / Chapter 1.1 --- Inductively coupled plasma-emission spectrometric analysis --- p.51 / Chapter 1.1.1 --- Heavy metal concentration in crude oily wastes --- p.51 / Chapter 1.1.2 --- Heavy metal concentration in water-soluble fraction --- p.51 / Chapter 1.1.3 --- Heavy metal concentration in ploy cyclic aromatic hydrocarbon fraction --- p.54 / Chapter 1.2 --- Gas chromatography- mass spectrometry analysis --- p.54 / Chapter 1.2.1 --- Polycyclic aromatic hydrocarbon concentration in crude oily wastes --- p.54 / Chapter 1.2.2 --- Polycyclic aromatic hydrocarbons concentration in water-soluble fraction --- p.59 / Chapter 1.2.3 --- Polycyclic aromatic hydrocarbons concentration in polycyclic aromatic hydrocarbon fraction --- p.61 / Chapter 2. --- Ecotoxicological studies of oily wastes --- p.63 / Chapter 2.1 --- Ecotoxicological studies of water-souble fraction --- p.63 / Chapter 2.1.1 --- Growth inhibition test on Chlorella pyrenoidosa CU-2 --- p.63 / Chapter 2.1.2 --- Survival test on Elasmopous rapax --- p.63 / Chapter 2.1.3 --- Survival test on Ambassis gymnocephalus --- p.67 / Chapter 2.1.4 --- Microtox® test --- p.67 / Chapter 2.2 --- Ecotoxicological studies of polycyclic aromatic hydrocarbon fraction --- p.70 / Chapter 2.2.1 --- Growth inhibition test on Chlorella pyrenoidosa CU-2 --- p.70 / Chapter 2.2.2 --- Survival test on Parhyale plumulosa --- p.70 / Chapter 2.2.3 --- Survival test on Sparus sarba --- p.74 / Chapter 2.2.4 --- Microtox® test --- p.74 / Chapter 3. --- Statistical analyses of chemical and ecotoxicological studies --- p.77 / Chapter 3.1 --- Statistical analyses of studies on water-soluble fraction --- p.77 / Chapter 3.1.1 --- Correlation between heavy metal concentration in water-soluble fraction and toxicity tests --- p.77 / Chapter 3.1.2 --- Correlation between concentration of total polycyclic aromatic hydrocarbon in water-soluble fraction and toxicity tests --- p.80 / Chapter 3.1.3 --- Correlation among acute toxicity tests --- p.80 / Chapter 3.2 --- Statistical analyses of polycyclic aromatic hydrocarbon fraction --- p.84 / Chapter 3.2.1 --- Correlation between heavy metal level and toxicity tests --- p.84 / Chapter 3.2.2 --- Correlation between total polycyclic aromatic hydrocarbon concentration in polycyclic aromatic hydrocarbon fraction and toxicity tests --- p.84 / Chapter 3.2.3 --- Correlation between four acute toxicity tests --- p.88 / DISCUSSION --- p.91 / Chapter 1 --- Chemical analyses of oily wastes --- p.91 / Chapter 1.1 --- Inductively coupled plasma-emission spectrometric analysis --- p.91 / Chapter 1.2 --- Gas chromatography-mass spectrometry analysis --- p.93 / Chapter 2. --- ecotoxicological studies of oily wastes --- p.95 / Chapter 2.1 --- Growth inhibition test on Chlorella pyrenoidosa CU-2 --- p.95 / Chapter 2.2 --- Survival tests on Elasmopus rapax and Parhyale plumulosa --- p.96 / Chapter 2.3 --- Survival test on Ambassis gymnocephalus and Sparus sarba --- p.97 / Chapter 2.4 --- Microtox® test --- p.98 / Chapter 3 --- Statistical analyses of chemical and ecotoxicological analyses --- p.99 / Chapter 4. --- statistical analyses between acute toxicity tests --- p.101 / CONCLUSION --- p.102 / REFERENCES --- p.104
19

Avalia??o de diferentes processos oxidativos avan?ados no tratamento de res?duos de petr?leo

Rocha, Otidene Rossiter S? da 01 September 2010 (has links)
Made available in DSpace on 2014-12-17T15:01:50Z (GMT). No. of bitstreams: 1 OtideneRSR_DISSERT.pdf: 1647726 bytes, checksum: 2a45d120fb2b82e3a84f67c77eff85a3 (MD5) Previous issue date: 2010-09-01 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The petroleum industry deals with problems which are difficult to solve because of their relation to environmental issues. This is because amounts of residue are generated which vary in type and danger level. The soil contamination by non aqueous liquid phase mixtures, specifically hydrocarbon petroleum has been a reason for great concern, mainly the aromatic and polycyclic aromatic, which present risk to human health due to its carcinogenic and mutagenic character. The Advanced Oxidative Processes (AOP) are efficient technologies for destruction of organic compounds of difficult degradation and, often, they are present in low concentrations. They can be considered clean technologies, because there is no formation of solid by-products or the transfer of pollutor phases. This work focuses on the study of the degradation of petroleum industrial waste, by Advanced Oxidation Processes. Treatments tackling petroleum residues, contaminated soil, and water occurring in the production of petroleum reached the following Polycyclic Aromatic Hydrocarbons (PAH) degradation levels: solid residues 100% in 96 treatment hours; water residue - 100% in 6 treatment hours; soil contamination (COT degradation) - 50.3% in 12 treatment hours. AOP were effective in dealing with petroleum residues thus revealing themselves to be a promising treatment alternative / A ind?stria de petr?leo lida com problemas de dif?cil solu??o em rela??o ?s atividades voltadas para a prote??o ambiental, devido ? gera??o de res?duos de diversos tipos e n?veis de periculosidade. A contamina??o do solo por compostos de fase l?quida n?o aquosa, especificamente os hidrocarbonetos de petr?leo tem sido motivo de preocupa??o, principalmente os arom?ticos e poliarom?ticos, apresentam risco ? sa?de humana devido a seu car?ter carcinog?nico e mutag?nico. Os Processos Oxidativos Avan?ados (POA) s?o tecnologias eficientes para destrui??o de compostos org?nicos de dif?cil degrada??o biol?gica e, muitas vezes, presentes em baixas concentra??es. Podem ser consideradas tecnologias limpas, pois n?o h? a forma??o de subprodutos s?lidos e nem a transfer?ncia de fase dos poluentes. O objetivo desse trabalho foi estudar a degrada??o de res?duos da ind?stria de petr?leo, por Processos Oxidativos Avan?ados. Foram realizados tratamentos de borra de petr?leo, solo contaminado com petr?leo e ?gua de produ??o de petr?leo alcan?ando uma degrada??o de Hidrocarbonetos Polic?clicos Arom?ticos (HPA) de 100 % em 96 horas de tratamento para a borra, 100% em 6 horas de tratamento para ?gua de produ??o de petr?leo e uma degrada??o de Carbono Org?nico Total (COT) de 50,3% em 12 horas de tratamento para o solo contaminado com petr?leo. Os POA foram eficientes no tratamento de res?duos de petr?leo apresentando-se como uma alternativa promissora no tratamento desses res?duos
20

Engineering of an enzyme cocktail for biodegradation of petroleum hydrocarbons based on known enzymatic pathways and metagenomic techniques

Baburam, Cindy 07 1900 (has links)
Ph. D. (Department of Biotechnology, Faculty of Applied and Computer Sciences), Vaal University of Technology. / Hydrocarbon pollution is becoming a growing environmental concern in South Africa and globally. This inadvertently supports the need to identify enzymes for their targeted degradation. The search for novel biocatalysts such as monooxygenases, alcohol dehydrogenases and aldehyde dehydrogenases, have relied on conventional culture-based techniques but this allows sourcing of the biomolecules from only 1-10 % of the microbial population leaving the majority of the biomolecules unaccounted for in 90-99 % of the microbial community. The implementation of a metagenomics approach, a culture-independent technique, ensures that more or less than 100 % of the microbial community is assessed. This increases the chance of finding novel enzymes with superior physico-chemical and catalytic traits. Hydrocarbon polluted soils present a rich environment with an adapted microbial diversity. It was thus extrapolated that it could be a potential source of novel monooxygenases, alcohol dehydrogenases (ADH) and aldehyde dehydrogenases (ALDH) involved in hydrocarbon degradation pathways. Therefore, the aim of the study was to extract metagenomic DNA from hydrocarbon contaminated soils and construct a metagenomic fosmid library and screen the library for monooxygenases, alcohol dehydrogenases (ADH) and aldehyde dehydrogenases (ALDH). Accordingly, the fosmid library was constructed from metagenome of hydrocarbon-contaminated soil. Then the library was functionally screened using hexadecane, octadecene and cyclohexane as substrates and fifteen positive clones were selected. The fosmid constructs of the positive clones were sequenced using PacBio next generation sequencing platform. The sequences were de novo assembled and analysed using CLC Genomic Workbench. The open reading frames (ORF) of the contigs were identified by blasting the contigs against uniport database. Accordingly, four novel genes namely amo-vut1, aol-vut3, dhy-sc-vut5 and dhy-g-vut7 that showed close similarity with our target enzymes were further analysed in silico and codon-optimized as per Escherichia coli codon preference. The codon adjusted sequences were synthesised and cloned into pET30a(+) expression vector. However, it is worth noting that expression of amo-vut1 was not successful since it was later identified to be a multi-pass member protein, which made it insoluble despite the use of detergent to the effect. There is a need to meticulously genetically engineer amo-vut1 to remove the signal and other membrane-bound peptides while maintaining its activity. Yet the other three constructs were successfully transformed and expressed in E. coli BL21 (DE3). The enzymes were purified and characterized and cocktail for hydrolysis of hexanol was succesfully engineered based on AOL-VUT3, DHY-SC-VUT5 and DHY-G-VUT7. Therefore, novel enzymes were mined from metagenome of fossil-oil contaminated soil and effective hydrocarbon-degrading enzyme cocktails containing their combination were successfully engineered.

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