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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.
291

Condition Assessment Technologies for Drinking Water and Wastewater Pipelines: State-of-the-Art Literature and Practice Review

Thuruthy, Nisha 07 June 2012 (has links)
Aging and deteriorating drinking water and wastewater pipelines have become a major problem in the United States, warranting significant federal attention and regulation. Many utilities have begun or improved programs to manage the renewal of their water and wastewater pipes and are proactively managing their pipeline assets rather than reactively fixing them. However, the extensive size of drinking water and wastewater systems and the severity of the deterioration problem are such that it is important to prioritize renewal, by assessing the condition of the pipelines and resolving the most severe situations first. There is a variety of condition assessment technologies and methodologies available and in current use. This research incorporates an extensive literature review on actual cases of use of these various condition assessment technologies and techniques. This research also compiles information gathered through interviews and data mining work with utilities across the United States. The combination of case studies collected through literature review and case studies collected directly from utility sources about actual application of drinking water and wastewater pipeline condition assessment practices used have made it possible to synthesize the current practices and trends regarding pipeline condition assessment in the United States. The synthesis also allows for the identification of key lessons learned that should be considered by utilities when implementing condition assessment of pipelines. Recommendations have also been made for research priorities for filling utility needs. / Master of Science
292

An assessment of the offstream storage requirements and low-flow frequencies characteristics to supply coal slurry piplines originating in southwestern Virginia

Santos, German R. (German Ricardo) January 1983 (has links)
M. S.
293

[pt] ANÁLISE TÉRMICA DA REMOÇÃO DE BLOQUEIOS DE PARAFINA EM LINHAS SUBMARINAS DE PETRÓLEO UTILIZANDO AQUECIMENTO INDUTIVO / [en] THERMAL ANALYSIS OF WAX BLOCKAGES REMOVAL IN PETROLEUM SUBSEA PIPELINES BY INDUCTIVE HEATING

RENATA CORREA SARMENTO 04 September 2002 (has links)
[pt] Bloqueio total de linhas submarinas de produção de petróleo devido ao depósito de parafina é um problema relevante para a indústria. Esse problema tem levado a perdas significativas associadas à diminuição de produção e à substituição de linhas obstruídas. O presente trabalho é um estudo sobre a viabilidade técnica de um procedimento para remoção de bloqueios ocasionados por depósitos de parafina. Nesse procedimento, a seção da linha de petróleo obstruída com parafina é aquecida por indução utilizando-se uma bobina externa posicionada sobre a linha no fundo do mar. O objetivo do trabalho é estimar o nível de potência elétrica necessária para amolecer a obstrução de parafina dentro da linha. Com esta finalidade, foi empregado um modelo numérico para simular o processo de condução de calor transiente para prever a distribuição de temperatura na parede da linha e na parafina sólida. Essa informação foi usada para estimar as dimensões básicas da seção da bobina de aquecimento e isolamento térmico empregado para minimizar as perdas de calor para o ambiente gelado da água do mar. Um estudo experimental de laboratório com uma seção de um duto submarino bloqueado com parafina foi conduzido para verificar as previsões do modelo numérico e para testar o desempenho da bobina de indução de aquecimento. Os resultados mostraram que as soluções numéricas obtidas apresentaram boa concordância com o experimento. Ainda, foi observado que os níveis de temperatura necessários para produzir o amolecimento da parafina na região bloqueada somente serão obtidos se toda a extensão da região bloqueada for aquecida pela ferramenta de indução. / [en] Total blockage of subsea petroleum production lines due to wax deposition is a relevant problem for the industry. This problem has led to significant capital losses associated with the loss of production and the substitution of plugged lines. The present work is a study of the feasibility of a remediation procedure aimed at helping the removal of wax plugs. In this procedure, the section of the oil line plugged with wax is inductively heated by means of an external coil positioned over the line at sea bed.The objective of the work is to estimate the level of electrical power required to soften the wax plug inside the line. To this end, a transient heat conduction model was employed to predict the temperature distribution in the line wall and solid wax. This information was employed to estimate the basic dimensions of the heating coil section and thermal insulation employed to minimize the heating losses to the cold sea water environment. A laboratory experimental study with a subsea pipeline section plugged with wax was conducted to verify the numerical model predictions and to test the performance of the inductive heating coil.The results showed that the numeric solutions obtained presented good agreement with the experiments. It was also observed that the necessary temperature levels to produce the paraffin softening in the blocked region will only be attained if the whole extension of the blocked region is heated by the induction tool.
294

L'Azerbaïdjan, les hydrocarbures et les pipelines : réseaux sociotechniques et régionalisation / Azerbaïdjan, hydrocarbon resources and pipelines : sociotechnical networks and regionalization

Lussac, Samuel 14 November 2011 (has links)
Cette recherche s’intéresse aux impacts sociopolitiques des gazoducs et des oléoducsmis en oeuvre depuis 1991 au Caucase du Sud. S’appuyant sur un cadre théoriquemêlant principalement sociologie de l’Acteur-Réseau, sociologie éliasienne etapproches managériales, elle postule que la construction d’un système complexe detransport de pétrole et de gaz azerbaïdjanais est révélatrice de l’évolution de laconfiguration sud-caucasienne. Cette thèse étudie tout d’abord les interactions qui senouent autour de la mise en oeuvre des voies d’exportation des hydrocarburesazerbaïdjanais. Elle met en lumière l’émergence de nouvelles formes de régulation, dontla plupart profite à la compagnie pétrolière BP. Elle démontre ensuite comment lesréseaux sociotechniques construits autour de ces nouvelles voies participent d’uneévolution de la configuration sud-caucasienne. Ces réseaux débordent du cadrepurement économique pour aboutir au développement de la régionalisation entrel’Azerbaïdjan, la Géorgie et la Turquie. Cette recherche souligne enfin les gains queretire l’Etat-entreprise azerbaïdjanais de cette régionalisation fondée sur leshydrocarbures. Bakou se sert de ces derniers pour étendre son influence économique etpolitique au sein de la configuration sud-caucasienne. La sociologie de l’Acteur-Réseaunous permet donc de souligner le rôle non seulement économique mais égalementpolitique des hydrocarbures dans la montée en puissance de l’Azerbaïdjan qui, d’Etat enfaillite, est devenu puissance régionale. / This dissertation looks at the socio-political impacts of the pipelines that have beenimplemented in the South Caucasus since 1991. It is based on a theoreticalframework mixing Actor-Network Theory, Norbert Elias’s sociology andmanagement approaches. It assumes that the construction of an Azerbaijanihydrocarbons transportation complex system sheds light into the evolution of theSouth Caucasian configuration. First, this research studies interactions that emergeLUSSAC Samuel | Science Politique | Doctorat | 201114around the implementation of export routes for Azerbaijani oil and gas resources.It highlights the development of new forms of governance, which mostly benefit tothe oil company BP. Second, this dissertation demonstrates that the sociotechnicalnetworks built around these new export routes contribute to the evolution of theSouth Caucasian configuration. These networks overflow the economic sphere tofoster regionalization between Azerbaijan, Georgia and Turkey. Third, thisresearch underlines the benefits the Azerbaijani ‘state-company’ retrieves fromthis hydrocarbons-based regionalization. Baku takes advantage of oil and gasresources to increase its economic and political influence within the SouthCaucasian configuration. Therefore, the Actor-Network Theory helps to shed lightinto the economic and political role of hydrocarbons in the rise of Azerbaijan.From a failed state, this country has now established itself as a regional power.
295

Post-project analysis in environment impact assessment: a case study of pipeline construction with special emphasis on soil management.

January 2001 (has links)
Yuen Siu-man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 158-180). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.vi / Table of Contents --- p.ix / List of Tablcs --- p.xvi / List of Figures --- p.xix / List of Plates --- p.xx / List of Appendices --- p.xxi / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- lntroduction --- p.1 / Chapter 1.2 --- The Problem --- p.5 / Chapter 1.2.1 --- Towngas pipeline --- p.5 / Chapter 1.2.2 --- Environmental impact assessment (EIA) --- p.6 / Chapter 1.2.3 --- Landscape restoration --- p.11 / Chapter 1.3 --- Conceptual Framework --- p.12 / Chapter 1.3.1 --- Ecosystem disturbance and soil impacts of pipeline construction --- p.12 / Chapter 1.3.2 --- Scope and baseline --- p.14 / Chapter 1.3.3 --- Mitigation and restoration guidelines --- p.16 / Chapter 1.4 --- Objectives of the Study --- p.18 / Chapter 1.5 --- Significance of the Study --- p.21 / Chapter 1.6 --- Scope of the Study --- p.22 / Chapter 1.7 --- Terminology in the Thesis --- p.23 / Chapter 1.8 --- Organization of the Thesis --- p.26 / Chapter Chapter 2 --- Literature Review / Chapter 2.1 --- Ecosystem Disturbance and Impacts of Pipeline Construction --- p.27 / Chapter 2.2 --- Soil as an Important Natural Resource --- p.29 / Chapter 2.3 --- Environmental Impact Assessment (EIA) --- p.31 / Chapter 2.3.1 --- Theory and practice of EIA --- p.31 / Chapter 2.3.2 --- EIA in Hong Kong --- p.33 / Chapter 2.3.3 --- Soil assessment in EIA --- p.34 / Chapter 2.3.4 --- Ecological impact assessment in EIA --- p.35 / Chapter 2.3.5 --- Mitigation --- p.36 / Chapter 2.3.6 --- Significance of impacts --- p.38 / Chapter 2.3.7 --- Weaknesses of EIA --- p.39 / Chapter 2.3.8 --- "Post-project analysis, monitoring and audits" --- p.41 / Chapter Chapter 3 --- Study Area and Methodology / Chapter 3.1 --- Introduction --- p.44 / Chapter 3.2 --- Climate --- p.46 / Chapter 3.3 --- Geology and Soils --- p.46 / Chapter 3.4 --- Study Plots --- p.48 / Chapter 3.5 --- Methodology --- p.56 / Chapter 3.5.1 --- Experimental design --- p.56 / Chapter 3.5.2 --- Fieldwork --- p.57 / Chapter 3.5.3 --- Laboratory analysis --- p.58 / Chapter 3.5.4 --- Date processing and statistical analysis --- p.61 / Chapter 3.5.5 --- EIA report review --- p.62 / Chapter Chapter 4 --- Soil Baseline / Chapter 4.1 --- Introduction --- p.63 / Chapter 4.2 --- Results --- p.64 / Chapter 4.2.1 --- Texture --- p.64 / Chapter 4.2.2 --- Bulk density --- p.65 / Chapter 4.2.3 --- Soil acidity --- p.65 / Chapter 4.2.4 --- Exchangeable acidity and aluminum --- p.66 / Chapter 4.2.5 --- Soil organic matter (SOM) --- p.67 / Chapter 4.2.6 --- Total and mineral nitrogen --- p.67 / Chapter 4.2.7 --- Total and available phosphorus --- p.69 / Chapter 4.2.8 --- Exchangeable cations --- p.70 / Chapter 4.2.9 --- "Effective cation exchange capacity (ECEC), base saturation (BS) and aluminum saturation" --- p.72 / Chapter 4.2.10 --- C/N ratio --- p.73 / Chapter 4.3 --- Discussion --- p.74 / Chapter 4.3.1 --- Acidity problem --- p.74 / Chapter 4.3.2 --- Soil texture and bulk density --- p.75 / Chapter 4.3.3 --- Soil organic matter and nitrogen --- p.76 / Chapter 4.3.4 --- Soil phosphorus --- p.78 / Chapter 4.3.5 --- "Exchangeable cations, ECEC. BS and aluminum saturation" --- p.78 / Chapter 4.3.6 --- Implications on landscape restoration --- p.80 / Chapter 4.4 --- Conclusion --- p.82 / Chapter Chapter 5 --- Impacts of Pipeline Construction on Soils / Chapter 5.1 --- Introduction --- p.84 / Chapter 5.2 --- Results --- p.85 / Chapter 5.2.1 --- "Soil acidity, exchangeable hydrogen and aluminum" --- p.86 / Chapter 5.2.2 --- Soil texture and bulk density --- p.88 / Chapter 5.2.3 --- Soil organic matter --- p.90 / Chapter 5.2.4 --- Soil TKN --- p.90 / Chapter 5.2.5 --- Phosphorus --- p.91 / Chapter 5.2.6 --- Soil exchangeable cations --- p.94 / Chapter 5.2.7 --- "ECEC, BS and aluminum saturation" --- p.96 / Chapter 5.3 --- Discussion --- p.99 / Chapter 5.3.1 --- Nature of the soil impacts --- p.99 / Chapter 5.3.2 --- Causes of soil impact --- p.101 / Chapter 5.3.3 --- Spatial difference of soil impacts --- p.108 / Chapter 5.3.4 --- Significance of the impacts --- p.111 / Chapter 5.3.5 --- Mitigation measures --- p.117 / Chapter 5.4 --- Conclusion --- p.120 / Chapter Chapter 6 --- Improvement of EIA on Soil Management / Chapter 6.1 --- Introduction --- p.122 / Chapter 6.2 --- Evaluation of Information Provided by the EIA --- p.124 / Chapter 6.2.1 --- Need of more detailed soil baseline --- p.124 / Chapter 6.2.2 --- Inadequate soil impact prediction --- p.126 / Chapter 6.2.3 --- Need of site-specific soil mitigation --- p.128 / Chapter 6.2.4 --- Soil management in EIA --- p.130 / Chapter 6.3 --- Soil Impact Assessment (SIA) --- p.136 / Chapter 6.3.1 --- Soil baseline --- p.138 / Chapter 6.3.2 --- Impact prediction and significance --- p.140 / Chapter 6.3.3 --- Mitigation in SIA --- p.142 / Chapter 6.3.4 --- Monitoring in SIA --- p.143 / Chapter 6.3.5 --- Post-project evaluation in SIA --- p.144 / Chapter 6.3.6 --- Application of SIA --- p.145 / Chapter 6.4 --- Conclusion --- p.146 / Chapter Chapter 7 --- Conclusion / Chapter 7.1 --- Summary of Findings --- p.147 / Chapter 7.1.1 --- Undisturbed soil conditions --- p.147 / Chapter 7.1.2 --- Soil impacts and resultant soil properties --- p.149 / Chapter 7.1.3 --- Evaluation of the EIA Report --- p.151 / Chapter 7.2 --- Implications --- p.152 / Chapter 7.2.1 --- Challenge to Aber's disturbance level theory --- p.152 / Chapter 7.2.2 --- Consolidation of impacts assessment in EIA --- p.153 / Chapter 7.2.3 --- Information for soil impact assessment --- p.154 / Chapter 7.3 --- Limitations of study --- p.154 / Chapter 7.4 --- Further Research --- p.156 / References --- p.158 / Appendices --- p.181
296

BEHAVIOUR OF BURIED PIPELINES SUBJECT TO NORMAL FAULTING

SAIYAR, MASOUMEH 01 February 2011 (has links)
Thesis (Ph.D, Civil Engineering) -- Queen's University, 2011-01-31 20:52:11.162 / One of the most severe hazards for buried pipelines, which are sometimes referred to as lifelines due to their essential role in delivering vital resources, is the hazard due to Permanent Ground Deformation (PGD). Earthquake induced PGD can be caused by surface faulting, landslides and seismic settlement. In this thesis, the behaviour of buried pipelines subject to normal faulting has been experimentally investigated through a series of centrifuge tests performed on both continuous and jointed pipelines. Both pipe and soil displacements were measured using image analysis. Signal processing techniques were then developed to filter this data so as to enable the calculation of curvature and other aspects of the response from the observed pipe deformations. First, a series of centrifuge tests was conducted on continuous pipelines of varying materials, representing a wide range of pipe stiffness relative to the soil and investigating the effect of pipe stiffness relative to the soil on soil-pipe interaction. The experimentally derived p-y curves at different locations along the pipe were compared to the recommended soil-pipe interaction models in the relevant guidelines. These p-y curves showed that the central shearing region was not captured well with independent soil springs. The response of the pipelines predicted by the ALA (2001) guideline, however, was shown to match the experimental data within 50%. Two new simplified design approaches were then developed. The first features calculations based on simplified pressure distributions. The second featured peak curvature normalized using a characteristic length, ipipe, the distance from peak to zero moment. A series of centrifuge tests using brittle pipes was also performed. The pipes were buried at three different depths, and the post-failure fracture angle of the pipe was measured to be used as an input for design of liners. Based on the experimental data, a computationally efficient approach was developed to estimate the initial fracture angle which occurs immediately after the pipe breaks. The last series of centrifuge tests was conducted on jointed pipelines with five different joint stiffnesses to investigate the flexural behaviour of jointed pipelines under normal faulting. Based on the observed pipe response, a simplified kinematic model was proposed to estimate the maximum joint rotation for a given geometry, pipe segment length, and the magnitude of the imposed ground displacement. / Ph.D
297

The application of remote sensing in the assessment of pipeline construction and oil spill impacts on farmland in Glengarry County, Ontario /

Paul, Morrie. January 1986 (has links)
No description available.
298

The Effect of Corrosion Defects on the Failure of Oil and Gas Transmission Pipelines: A Finite Element Modeling Study

Orasheva, Jennet 01 January 2017 (has links)
The transportation of oil and gas and their products through the pipelines is a safe and economically efficient way, when compared with other methods of transportation, such as tankers, railroad, trucks, etc. Although pipelines are usually well-designed, during construction and later in service, pipelines are subjected to a variety of risks. Eventually, some sections may experience corrosion which can affect the integrity of pipeline, which poses a risk in high-pressure operations. Specifically, in pipelines with long history of operation, the size and location of the corrosion defects need to be determined so that pressure levels can be kept at safe levels, or alternatively, a decision to repair or replace the pipe section can be made. To make this decision, there are several assessment techniques available to engineers, such as ASME B31G, MB31G, DNV-RP, software code called RSTRENG. These assessment techniques help engineers predict the remaining strength of the wall in a pipe section with a corrosion defect. The corrosion assessment codes in the United States, Canada and Europe are based on ASME-B31G criterion for the evaluation of corrosion defects, established based on full-scale burst experiments on pipes containing longitudinal machined grooves, initially conducted in 1960s. Because actual corrosion defects have more complex geometries than machined grooves, an in-depth study to validate the effectiveness of these techniques is necessary. This study is motivated by this need. The current study was conducted in several stages, starting with the deformation behavior of pipe steels. In Phase 1, true-stress-true plastic strain data from the literature for X42 and X60 steel specimens were used to evaluate how well four commonly used constitutive equations, namely, those developed by Hollomon, Swift, Ludwik and Voce, fit the experimental data. Results showed that all equations provided acceptable fits. For simplicity, the Hollomon equation was selected to be used in the rest of the study. In Phase 2, a preliminary finite element modeling (FEM) study was conducted to compare two failure criteria, stress-based or strain-based, performed better. By using data from the literature for X42 and X60 pipe steels, experimental burst pressure data were compared with predicted burst pressure data, estimated based on the two failure criteria. Based on this preliminary analysis, the stress-based criterion was chosen for further FEM studies. In Phase 3, failure data from real corrosion pits in X52 pipe steels with detailed profiles were used to develop a FEM scheme, which included a simplified representation of the defect. Comparison of actual and predicted burst pressures indicated a good fit, with a coefficient of determination (R2) level of 0.959. In Phase 4, burst pressure levels were estimated for real corrosion pits for the experiments from the same study as in Phase 3, but only with corrosion pit depths and length and without corrosion widths. Widths were estimated from the data used in Phase 3, by using an empirical equation as a function of pit length. There was significant error between experimental and predicted burst pressure. Errors in Phases 3 and 4 were compared statistically. Results showed that there is a statistically significant difference in the error when the width of the corrosion pit is unknown. This finding is significant because none of the assessment techniques in the literature takes width into consideration. Subsequently, a parametric study was performed on three defect geometries from the same study in Phase 3. The pit depths and lengths were held constant but widths were changed systematically. In all cases, the effect of the pit width on burst pressure was confirmed. In Phase 5, the three assessment techniques, ASME B31G, MB31-G and DNV-RP were evaluated by using experimental test results for X52 pipe. Synthetic data for deeper pits were developed by FEM and used along with experimental data in this phase. Two types of the error were distinguished to classify defects. Type I errors (α) and Type II errors (β) were defined using Level 0 evaluation method. Results showed that although ASME B31G is the most conservative technique, it is more reliable for short defects than MB31G and DNV-RP. The least conservative technique was DNV-RP but it yielded β error, i.e., the method predicted a safe operating pressure and pipe section would fail. Therefore, DNV-RP is not recommended for assessment of steel pipes, specifically for X52 pipes.
299

Problematika fungování potrubní přepravy v rámci světových obchodních operací s plynem a ropou / Problems of pipeline functioning in global business oil and gas operations

Shtanko, Elizaveta January 2011 (has links)
Under the current intensive development of the world economy, there is a significant increase in integration of strategic sectors in countries towards the regional and international networks. Therefore, the potential of pipeline transport begins to take special foreign economic and geopolitical importance. The current status and development of this field is the object of an increased interest of all parties that are involved in the transport of raw materials. The more trades there are with oil and gas, the more issues related to its transport are occurred which all parties involved in the transport system faced to deal with. In the context of rapidly developing interconnection of global economies on regional level along with its undeniable reflection on international situation, it makes the functioning of already existing system of pipelines and realization of new projects related to construction of pipelines, with issues of economic, ecological and technical character that play an important role in delivering strategic energy products to world markets. At the same time the strong competition for the construction of pipeline facilities increases its geopolitical significance.
300

The application of remote sensing in the assessment of pipeline construction and oil spill impacts on farmland in Glengarry County, Ontario /

Paul, Morrie. January 1986 (has links)
No description available.

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