[pt] A energia desempenha um papel estratégico global, com a indústria do petróleo sendo uma fonte crucial. No entanto, iniciativas visando reduzir a dependência do petróleo surgem, impulsionadas principalmente por preocupações ambientais, como as mudanças climáticas. A transição energética ganha destaque nas agendas nacionais, refletindo a interligação entre energia e meio ambiente. Apesar da redução na previsão de crescimento da demanda a indústria global de petróleo e gás, a indústria do petróleo permanece vital, sustentando fontes de energia, gerando receitas e empregos. Contudo, a indústria enfrenta pressões ambientais crescentes, destacando a necessidade de investir continuamente em segurança nas operações de exploração de poços. O blowout, apesar de ser evento com baixa probabilidade de ocorrência, representa uma ameaça grave, não apenas para a imagem da empresa, mas também para o meio ambiente e a vida das pessoas. O exemplo do blowout de Macondo, ocorrido no Golfo do Mexico, em operação da British Petroleum (BP) evidencia os impactos significativos. O combate ao blowout envolve mitigação de impacto e controle da fonte. Estratégias essenciais para mitigação de impactos e o controle da fonte incluem o fechamento do poço com equipamento de bloqueio (capping) e a construção de um poço de alívio. O primeiro é uma ação rápida para fechar o poço e cessar o vazamento de hidrocarboneto para o meio ambiente, enquanto o segundo visa construir um poço adicional para interceptar, amortecer e abandonar de forma definitiva o poço em blowout. O presente trabalho concentra-se em apresentar soluções para amortecimento do poço em blowout via poço de alívio em situações que exigem altas vazões e volumes. Simulações revelam desafios técnicos, como demandas de grandes volumes e altas vazões de amortecimento. Portanto, a pesquisa busca oferecer soluções diferenciadas para atender a essas demandas específicas e contribuir para a segurança e eficácia das operações. / [en] Energy plays a global strategic role, with the oil industry being a crucial source. However, initiatives aimed at reducing dependence on oil are emerging, mainly driven by environmental concerns such as climate change. Energy transition gains prominence in national agendas, reflecting the interconnectedness between energy and the environment. Despite the reduction in the demand growth forecast, the global oil and gas industry, the oil industry remains vital, sustaining energy sources, generating revenue, and jobs. However, the industry faces increasing environmental pressures, highlighting the need for continuous investment in safety in well drilling operations. Blowouts, although events with low probability of occurrence, represent a serious threat not only to the company s image but also to the environment and people s lives. The example of the Macondo blowout in the Gulf of Mexico, during British Petroleum (BP) operation, illustrates significant impacts. Combatting blowouts involves impact mitigation and source control. Essential strategies for impact mitigation and source control include well capping and the construction of a relief well. The former is a rapid action to close the well and stop hydrocarbon leakage into the environment, while the latter aims to build an additional well to intercept, killing, and permanently abandon the blowout well. This work focuses on presenting solutions for blowout well killing via relief well in situations requiring high flow rates and volumes. Simulations reveal technical challenges, such as demands for large volumes and high pump rates. Therefore, the research seeks to offer differentiated solutions to meet these specific demands and contribute to the safety and effectiveness of operations.

No description available.

Dans les filtres plantés de roseaux à écoulement vertical, la percolation des eaux usées à travers le milieu filtrant entraine la rétention physique des matières en suspension à la surface des filtres, et leur accumulation conduit à la formation d’une couche de boue principalement sur le premier étage des filtres. Longtemps considérée comme un facteur de risque de colmatage, cette couche de surface est aussi un compartiment majeur de la performance du système. Dans l’objectif de mieux connaitre la nature et l’évolution des dépôts qui la constituent, des échantillons issus de 14 stations en fonctionnement ont été prélevés pour analyser notamment la nature de leur matière organique particulaire et son évolution. Les résultats ont montré que les dépôts de stations de plus de trois ans de fonctionnement tendent vers un état similaire, caractérisé par la présence de composés organiques stables et complexes et par une plus faible réactivité de la matière organique particulaire. Les dépôts provenant de stations de moins d’un an de fonctionnement présentent une signature particulière, caractérisée par une matière organique réactive et peu mature. En complément de cette évolution en surface du filtre, la matière organique particulaire des eaux usées entrantes peut également subir des modifications au sein du process d’un filtre planté de roseaux. La présence d’un lit bactérien comme traitement additionnel participe à l’hydrolyse et à la transformation de la matière organique particulaire par des processus de minéralisation et d’humification. L’ajout de chlorure ferrique favorise l’agrégation de la matière. Enfin, des polluants organiques et métalliques d’intérêt ont fait l’objet d’une première quantification dans ces dépôts afin d’estimer leur rétention pour mieux appréhender les risques potentiels en cas de dysfonctionnement ou d’épandage. L’étude du comportement à la lixiviation en fonction du pH a permis de mettre en évidence que la libération de certains éléments traces est liée à celle de la matière organique. / The percolation of unsettled wastewater in French Vertical Flow Constructed Wetlands (VFCWs) causes the formation of a sludge layer at the surface of the first stage filter due to the retention of sludge deposits. Although the growth of this layer over the years of operation is a potential source of clogging risks, it also largely contributes in the performance of the system, depending on its properties. In order to better understand these phenomena, surface sludge deposits samples taken from 14 VFCW sewage treatment plants were collected and analyzed. Results showed that the structure and composition of the sludge deposits from treatment plants with more than three years of operation time were remarkably similar, characterized by the presence of stable and complex organic compounds and a low reactivity and biodegradability of the particulate organic matter. Deposits from treatment plants with less than one year of operation time were composed of more reactive and less mature organic matter. The particulate organic matter of the inflow wastewater was also shown to undergo modifications within the treatment chain of the vertical flow constructed wetland. The implementation of a biological trickling filter as an additional treatment prior to the filter stages was found to induce the transformation of soluble and particulate organic matter through mineralization and hydrolysis, and to contribute to humification probably by the detachment of biofilm fragments. The injection of ferric chloride used to precipitate phosphates was found to promote aggregation within the sludge deposits. Finally, the role of the sludge layer in the retention of a selection of organic and metallic pollutants in VFCW systems has been evaluated by analyzing sludge deposits samples. Detergents were found at higher concentrations than PCPP. The potential release of the sorbed contaminants was studied using leaching tests as a function of pH. Results showed that the release of some trace metals (mostly copper) was governed by the leaching behavior of organic matter.

Les Stations de Traitement des Eaux Usées (STEU) sont l'une des principales sources de rejet de résidus médicamenteux dans l'environnement. Depuis 2009, les Zones de Rejet Végétalisées (ZRV) sont mises en oeuvre entre le rejet de la STEU et le milieu récepteur, mais leurs capacités d'abattement sont encore peu étudiées. Pour combler ce manque, les performances d'épuration de 2 STEU et de leur ZRV, ont été évaluées pendant 2 années. Les résidus médicamenteux (86) ont eu une majorité de rendements d'épuration compris entre 30 et 70 % dans les ZRV et avec des maximums en été et des minimums en hiver. Relativement aux abattements observés sur les STEU en amont, la contribution des ZRV à l'épuration globale du site était inférieure à 30 % du flux entrant. Aussi, la réduction des volumes d'eau rejetés au milieu naturel a été corrélée avec une augmentation des concentrations en résidus médicamenteux. Par ailleurs, les plantes ont montré une capacité d'absorption des médicaments spécifique à l'espèce étudiée, alors que l'observation des concentrations dans les boues, a mis en évidence une tendance à une adsorption en été et un relargage en hiver des micro-polluants. / Wastewater Treatment Plants (WWTP) are considered as one of the most important pharmaceutical compound discharges into the environment. Since 2009, French Water Agencies, promote Surface Flow Treatment Wetlands (SFTWs) at the outlet of WWTPs, between the WWTP and the receiving aquatic environment but their removal efficiencies are not well investigated. To overcome these lacks of knowledge, pollutant removal efficiencies of 2 WWTP and their SFTW were monitoring during 2 years. ln regard to pharmaceutical compounds (86), SFTW removal efficiency rates ranged from 30 to 70% with maximum values in summer and minimum values in winter. The SFTW removal efficiency contributions to WWTP were inferior to 30%. ln addition, SFTW inflow reductions were correlated with an increase of drug compound concentrations in the outflow. Furthermore, there was a specific absorption of these micro pollutants by plants whereas there were dynamic interactions between sampled mud and drugs residues with an adsorption during summer and a release during winter.

New technologies, such as an efficient vapor-compression evaporator, a stationary lime kiln (SLK), and the MixAlco process, compelled us to re-evaluate methods for producing sugar from cane. These technologies allow more water and lime to be used, and they add more value to bagasse. Extracting and preserving the sugars, and lime pretreating the bagasse to enhance biodigestibility, all at the same time in a pile, was demonstrated to be unfeasible; therefore, sugar extraction must occur before lime treating the bagasse. Sugar extraction should occur countercurrently by lixiviation, where liquid moves in stages opposite to the soaked bagasse (megasse), which is conveyed by screw-press conveyors that gently squeeze the fiber in each stage, improving extraction. The performance of a pilot-scale screw-press conveyor was tested for dewatering capabilities and power consumption. The unoptimized equipment decreased megasse moisture from 96 to 89%. Simulation of the process suggested that eight stages are necessary to achieve 98% recovery from typical sugarcane. The cumulative power for the screw-press conveyor system was 17.0±2.1 hp•h/ton dry fiber. Thin raw juice preserved with lime for several months showed no sucrose degradation and no quality deterioration, except for reducing sugar destruction. The lime loading needed for 1-year preservation is 0.20 g Ca(OH)2/g sucrose. Shorter times require less lime. After preservation, the juice was carbonated and filtered, and the resulting sludge pelletized. Due to their high organic content, the pellets were too weak for calcination temperatures used in the SLK. The organics must be decreased prior to pelletization and sodium must be supplemented as a binding agent. Long-term lime pretreatment of bagasse showed two delignification phases: bulk (rapid) and residual (slow). These were modeled by two simultaneous first-order reactions. Treatments with air purging and higher temperatures (50 – 57oC) delignified more effectively, especially during the residual phase, thus yielding higher cellulase-enzyme digestibilities after 2 – 8 weeks of treatment. At temperatures > 60oC, pure oxygen purging is preferred. Fresh bagasse was of better quality than old bagasse. Treatment with NaOH yielded a larger bulk delignification phase than Ca(OH)2. Long-term lime pulping of bagasse was unsuitable for copy-quality paper, but it was appropriate for strawboard and other filler applications.

No description available.

The need for energy and the associated economic benefits from the oil and gas deposits found mainly in the Niger Delta region of Nigeria necessitated the exploration and exploitation activities being carried out by the oil and gas Companies. However, these exploration and exploitation activities due to their unpredictable nature have a huge potential for environmental pollution as been experienced in the form of oil spills, gas flaring, irresponsible disposal of waste and several other activities that have resulted in the environmental degradation of the Niger Delta region. In the light of these, the Federal Government of Nigeria having experienced the consequences of pollution of the environment during the Koko Toxic Waste Dump incident in the then Bendel State in 1987 established a regulatory body tasked with the responsibility of harmonizing the economic interest from the oil and gas exploration and exploitation activities with the sustainability of the natural environment by developing well structured and articulated policies aimed at guiding the operations of the oil and gas operators, track their compliance and administer appropriate punitive measures for non compliance. However, this research work which is aimed at evaluating the impact of the environmental protection policies in upstream oil and gas activities in the Niger Delta region, involved the use of questionnaires and interviews. These questionnaires were completed by the management and staff of three major oil and gas companies operating within the area, the Department of Petroleum Resources and members of the Host communities. The interview was carried out to provide relevant feedback on their assessment of the impact made by the environmental protection policies on the upstream oil and gas activities in their operational areas/host communities. The study however concluded that “Although there is a regulatory body tasked with the responsibility to develop, implement and track compliance of the environmental protection policies in the upstream oil industry, the body is ineffective and as such the impact of the environmental protection policies is inadequate. Appropriate informed recommendations on the improvement strategies to the identified gaps that resulted in the unfavorable conditions were also provided. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2011

The need for energy and the associated economic benefits from the oil and gas deposits found mainly in the Niger Delta region of Nigeria necessitated the exploration and exploitation activities being carried out by the oil and gas Companies. However, these exploration and exploitation activities due to their unpredictable nature have a huge potential for environmental pollution as been experienced in the form of oil spills, gas flaring, irresponsible disposal of waste and several other activities that have resulted in the environmental degradation of the Niger Delta region. In the light of these, the Federal Government of Nigeria having experienced the consequences of pollution of the environment during the Koko Toxic Waste Dump incident in the then Bendel State in 1987 established a regulatory body tasked with the responsibility of harmonizing the economic interest from the oil and gas exploration and exploitation activities with the sustainability of the natural environment by developing well structured and articulated policies aimed at guiding the operations of the oil and gas operators, track their compliance and administer appropriate punitive measures for non compliance. However, this research work which is aimed at evaluating the impact of the environmental protection policies in upstream oil and gas activities in the Niger Delta region, involved the use of questionnaires and interviews. These questionnaires were completed by the management and staff of three major oil and gas companies operating within the area, the Department of Petroleum Resources and members of the Host communities. The interview was carried out to provide relevant feedback on their assessment of the impact made by the environmental protection policies on the upstream oil and gas activities in their operational areas/host communities. The study however concluded that “Although there is a regulatory body tasked with the responsibility to develop, implement and track compliance of the environmental protection policies in the upstream oil industry, the body is ineffective and as such the impact of the environmental protection policies is inadequate. Appropriate informed recommendations on the improvement strategies to the identified gaps that resulted in the unfavorable conditions were also provided. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2011

Thesis (Ph.D.)--Australian National University, 2005.

O crescimento populacional acelerado é o grande motivador para o desenvolvimento do setor da construção civil e o aumento na demanda por água potável, tendo como consequência, um aumento gradativo na geração de resíduos sólidos. Dessa forma, este trabalho foi realizado com o intuito de reciclar resíduos industriais e municipais incorporando-os em materiais para a construção civil. O compósito produzido a partir de lodo de estação de tratamento de água e lama de polimento de mármore, aplicando resíduo de produção de cal como ligante, foi avaliado quanto ao seu desempenho mecânico e sua estrutura morfológica. As matérias-primas foram caracterizadas quanto sua composição química, mineralógica,morfológica, granulométrica e, também, o teor de umidade. Com os materiais caracterizados, foram desenvolvidas nove composições variando-se o teor de lodo de estação de tratamento de água entre 25 e 50%, o teor de lama de polimento de mármore entre 35 e 50% e o resíduo de produção de cal entre 10 e 30%. Os compósitos foram submetidos a ensaios de resistência mecânica, absorção de água, análise química, mineralógica e morfológica. Os materiais desenvolvidos apresentaram, no 3° dia de cura, valor de resistência mecânica máxima de 4,65 MPa, no 7° dia 6,36 MPa, no 14° dia 6,74 MPa, no 28° dia 5,98 MPa, no 60° dia 8,52 MPa, no 90° dia 11,75 MPa e no 180° dia 12,06 MPa. Os valores de absorção de água aos 28 dias de cura variaram de 16,27 a 26,32% e aos 90 dias, de 13,57 a 23,56%. / The rapid population growth is the great motivator for the development of the construction industry and the increased demand for drinking water, resulting in a gradual increase in the generation of solid waste. Thus, this work was carried out in order to recycle industrial and municipal wastes incorporating them into materials for civil construction. The composite produced from water treatment sludge and marble polishing mud, applying lime production waste as a binder, was evaluated for its mechanical performance and its morphological structure. The raw materials were characterized for their chemical composition, mineralogy, morphology, particle size and also the moisture content. With the featured materials nine compositions have been developed varying the content of the water treatment sludge between 25 to 50%, marble polishing mud between 35 to 50% and the lime production waste between 10 to 30%. The composites were subjected to mechanical strength tests, water absorption, chemical and mineralogical composition and morphology. The developed materials presented, on the 3rd day of hydration, maximum strength value of 4.65 MPa, the 7th day 6.36 MPa, on the 14th day 6.74 MPa, the 28th day 5.98 MPa, on the 60th day 8.52 MPa at 90th day 11.75 MPa and 180th day 12.06 MPa. The water absorption values after 28 days of hydration ranged from 16.27% to 26.32% and after 90 days, from 13.57% to 23.56%.