Estudio y desarrollo de sensores de fibra óptica para detección de vibraciones en ductos ascendentes submarinos

En esta tesis doctoral se describe el trabajo de investigación enfocado al estudio y desarrollo de sensores de fibra óptica para la detección de presión, flujo y vibraciones en ductos ascendentes submarinos utilizados en la extracción y transporte de hidrocarburos, con el objetivo de aplicarlos en los campos de explotación de aguas profundas en el Golfo de México pertenecientes a la Industria Petrolera Mexicana. El trabajo se ha enfocado al estudio y desarrollo de sensores ópticos cuasi distribuidos y distribuidos. En especial se ha profundizado en el uso y aplicación de las redes de Bragg (FBG) y de reflectómetros ópticos en el dominio del tiempo sensible a la fase (φ-OTDR). Los sensores de fibra óptica son especialmente interesantes para estas aplicaciones por sus ventajosas características como su inmunidad a interferencias electromagnéticas, capacidad de multiplexado, fiabilidad para trabajar en ambientes hostiles, altas temperaturas, altas presiones, ambientes salino-corrosivos, etc. Además, la fibra óptica no solo es un medio sensor sino que puede usarse como medio de transmisión. Se ha realizado un estudio del estado del arte y las ventajas que presentan los sensores ópticos puntuales, cuasi-distribuidos y distribuidos con respecto a los sensores convencionales. Se han estudiado y descrito los interrogadores de redes de Bragg y se ha desarrollado un método de calibración útil para los interrogadores existentes en el mercado, consiguiendo incertidumbres en la medida de la longitud de onda menores de ± 88 nm e incertidumbres relativas (la mas interesante en el campo de los sensores) menores de ±3 pm. Centrándose en la aplicación de las redes de Bragg en la industria del petróleo, se ha realizado un estudio en detalle del comportamiento que presentan las FBGs en un amplio rango de temperaturas de -40 ºC a 500 oC. Como resultado de este estudio se han evaluado las diferencias en los coeficientes de temperatura en diversos tramos de mas mismas, así como para diferentes recubrimientos protectores. En especial se ha encontrado y evaluado las diferencias de los diferentes recubrimientos en el intervalo de temperaturas entre -40 ºC y 60 ºC. En el caso del intervalo de altas temperaturas, entre 100 ºC y 500 ºC, se ha medido y comprobado el cambio uniforme del coeficiente de temperatura en 1pm/ºC por cada 100 ºC de aumento de temperatura, en redes independientemente del fabricante de las mismas. Se ha aplicado las FBG a la medición de manera no intrusiva de la presión interna en una tubería y a la medición del caudal de un fluido en una tubería, por la medida de diferencia de presión entre dos puntos de la misma. Además se ha realizado un estudio de detección de vibraciones en tuberías con fluidos. Finalmente, se ha implementado un sistema de detección distribuida de vibraciones aplicable a la detección de intrusos en las proximidades de los ductos, mediante un φ-OTDR. En este sistema se ha estudiado el efecto negativo de la inestabilidad de modulación que limita la detección de vibraciones distribuidas, su sensibilidad y su alcance. ABSTRACT This thesis describes the research work focused for the study and development of on optical fiber sensors for detecting pressure, flow and vibration in subsea pipes used in the extraction and transportation of hydrocarbons, in order to apply them in deepwater fields in the Gulf of Mexico belonging to the Mexican oil industry. The work has focused on the study and development of optical sensors distributed and quasi distributed. Especially was done on the use and application of fiber Bragg grating (FBG) and optical reflectometers time domain phase sensitive (φ-OTDR). The optical fiber sensors especially are interesting for these applications for their advantageous characteristics such as immunity to electromagnetic interference, multiplexing capability, reliability to work in harsh environments, high temperatures, high pressures, corrosive saline environments, etc. Furthermore, the optical fiber is not only a sensor means it can be used as transmission medium. We have performed a study of the state of the art and the advantages offered by optical sensors point, quasi-distributed and distributed over conventional sensors. Have studied and described interrogators Bragg grating and has developed a calibration method for interrogators useful for the existing interrogators in the market, resulting uncertainty in the measurement of the wavelength of less than ± 0.17 nm and uncertainties (the more interesting in the field of sensors) less than ± 3 pm. Focusing on the application of the Bragg gratings in the oil industry, has been studied in detail the behavior of the FBGs in a wide range of temperatures from -40 °C to 500 oC. As a result of this study we have evaluated the difference in temperature coefficients over various sections of the same, as well as different protective coatings. In particular evaluated and found the differences coatings in the range of temperatures between -40 º C and 60 º C. For the high temperature range between 20 ° C and 500 ° C, has been measured and verified the uniform change of the temperature coefficient at 1pm / ° C for each 100 ° C increase in temperature, in networks regardless of manufacturer thereof. FBG is applied to the non-intrusive measurement of internal pressure in a pipeline and measuring flow of a fluid in a pipe, by measuring the pressure difference between two points thereof. Therefore, has also made a study of detecting vibrations in pipes with fluids. Finally, we have implemented a distributed sensing system vibration applied to intrusion detection in the vicinity of the pipelines, by φ-OTDR. In this system we have studied the negative effect of modulation instability limits the distributed vibration detection, sensitivity and scope.

Arquitecturas desplazadas. Rafael Bergamín y las arquitecturas del exilio español en Venezuela

El siglo XX ha sido el siglo de los desplazamientos. Una ingente cantidad de personas fueron forzadas por motivos políticos, o se vieron obligadas por motivos económicos, a abandonar sus territorios de origen, generando un distanciamiento que en la mayoría de los casos resultaría irrecuperable. Las penurias vividas en Europa, las oportunidades que se abrían en países americanos, o la presión ejercida por los regímenes totalitarios, llevaron a un buen número de profesionales, artistas e intelectuales europeos a territorio americano. El presente trabajo se propone indagar sobre una de esas migraciones que se establecieron en Latinoamérica en la primera mitad del siglo XX: la de los arquitectos españoles que se vieron forzados al exilio. Para ello se busca poner en evidencia no sólo sus aportaciones sino también la influencia que ejerció en su obra la cultura de los países de adopción. Venezuela recibió gran parte del contingente de arquitectos españoles desplazados como consecuencia de la Guerra Civil. Tras México fue el país que mayor número acogió. La llegada de dichos exiliados coincidió con el momento en que la sociedad venezolana, de base agrícola y comercial, pasaría a evidenciar el impacto de la revolución petrolera. Así pues, dicha llegada supuso no sólo la dramática pérdida del mundo previo, implícita en todo exilio, sino el arribo a una sociedad en profundo proceso de cambio. En ambos casos se trataba de “mundos que se desvanecen”. Se propone la asunción de la obra de dichos profesionales como una arquitectura desplazada. Un desplazamiento que se produce en dos sentidos: por un lado, se trata de un desplazamiento físico, por otro, la palabra desplazada habla también de la condición secundaria que adquiere la arquitectura ante el drama vital y de supervivencia que afectó a los exiliados. Así pues, a un desplazamiento físico, verificable, se une un desplazamiento en cuanto al nivel de importancia y de atención asignado a la arquitectura. El trabajo comprende una introducción, cuatro capítulos, y un epílogo, a modo de conclusión. A lo largo de dichos capítulos se conjugan el enfoque individual en la obra de uno de estos arquitectos desterrados, Rafael Bergamín, y la visión “coral” de diversas trayectorias vitales que enfrentaron un destino común. Se elige la figura de Bergamín como eje de desarrollo debido a la presencia significativa que tuvo su obra tanto en España como en Venezuela, y por la caracterización de la misma como obra construida en colaboración. La introducción, “Exilios arquitectónicos”, muestra el sustrato estructural, la fundamentación y la metodología empleada, incluyendo “problematizaciones” sobre el exilio arquitectónico. El primer capítulo, “Memoria de partida”, da cuenta de la formación y actuación, durante la preguerra, de los arquitectos españoles que saldrían al exilio. Se introduce un esquema de base generacional y se revela un panorama para nada unívoco. El segundo capítulo, “Guerra y salida al exilio”, aborda la actuación de dichos arquitectos durante la contienda bélica así como la posterior dispersión general del exilio. El tercer capítulo, “Construir desde lo que se desvanece. Arquitectos del exilio español en Venezuela”, propone diversos presupuestos conceptuales en torno al tema del desplazamiento en la arquitectura, revisando la adscripción disciplinar y profesional de los arquitectos españoles exiliados en Venezuela. El cuarto capítulo, “El regreso”, versa sobre el recorrido final de estos arquitectos. Como marco general, se revisa su itinerario de regreso o, en muchos casos, la imposibilidad de retorno. Por último, se dispone la fuente de los diversos documentos de archivos y repositorios, así como el aparato bibliográfico y referencial, empleados en la investigación. Tres anexos se adjuntan al corpus del trabajo. El primero presenta documentos inéditos, hallados durante el pertinente proceso de investigación; el segundo, dibujos de Bergamín, básicamente de las primeras décadas del siglo XX: caricaturas, anuncios y trabajos de la Escuela; el tercero, un esbozo biográfico de los arquitectos del exilio español. ABSTRACT The 20th Century has been the century of displacements. An enormous number of people were forced to leave their homelands for political or economic reasons, which generated a gap that in most of the cases would be unrecoverable. The hardships that people had to endure in Europe, the opportunities that emerged in American countries, or the pressure exerted by totalitarian regimes drove a good number of European professionals, artists and intellectuals to American territory. This research study is intended to investigate one of those migrations that settled in Latin America during the first half of the 20th century: the one of the Spanish architects that were forced into exile. To achieve this, an attempt was made to expose not only their contributions but also the influence that the culture of the countries which welcomed them exerted in their work. Venezuela received a large portion of Spanish architects who were displaced as a consequence of the Civil War. After Mexico, it was the country that sheltered the greatest number of persons. The arrival of these exiled Spanish architects coincided with the moment in which the Venezuelan society – based on agriculture and commerce – would witness the impact of the revolution of the oil industry. Thus, their arrival supposed not only experiencing the dramatic loss of their previous world – implicit in the notion of the exile – but also settling in a society going through a profound change process. In both cases it was about “two worlds that were vanishing.” The assumption of these architects’ work is regarded as a displaced architecture. A displacement that takes place in two ways: on one hand, there was a physical displacement, and on the other hand, the word displaced also talks about the second place that architecture is given when confronted with the urgent drama of survival that affected the exiled community. Hence, a physical, verifiable displacement is combined with a displacement that has to do with the importance and the attention given to architecture. This research study encompasses an introduction, four chapters, and an epilogue as a conclusion. Throughout the chapters, the individual approach to the work of one of these exiled architects, Rafael Bergamín, runs in parallel to an overall view of various other architects’ career paths that faced a common destiny. The work of the architect Bergamín was chosen as the center of this research study due to the significant presence that his work had in Spain as well as in Venezuela, and because its main characteristic was that it was built in collaboration with other architects. The introduction, “Architectural exiles”, shows the structural contextualization, the explanatory thesis statement and the methodology used, including “problematizations” about the architectural exile. The first chapter, “Memory of departure”, contains the academic background and performance during the pre-war time of the Spanish architects that would go into exile. An outline based on different generations and revealing an unambiguous perspective is introduced. The second chapter, “War and departure into exile”, tackles the performance of the Spanish architects during the war, as well as the following general diaspora into exile. The third chapter, “Building from what vanishes. Architects of the Spanish exile in Venezuela”, proposes various conceptual assumptions concerning the topic of displacement in architecture according to the doctrine and professional affiliations of the Spanish architects exiled in Venezuela. The fourth chapter, “The return”, deals with the end of these architects’ careers. As a general framework, their itineraries to return, or in many cases, the impossibility of returning, are reviewed. Finally, the sources to the various documents of files and repositories, as well as the bibliographical references consulted for the research, are provided. Three annexes have been attached to this research study. The first annex contains unpublished documents found during the research process; the second includes Bergamín’s drawings, basically from the first decades of the 20th century, such as, caricatures, advertisements and assignments done when he was a university student; and the third annex presents a biographical outline of the architects of the Spanish exile.

Facing the climate change challenges in the mining and mineral industry as providers of a sustainable manufacturing process

A sustainable manufacturing process must rely on an also sustainable raw materials and energy supply. This paper is intended to show the results of the studies developed on sustainable business models for the minerals industry as a fundamental previous part of a sustainable manufacturing process. As it has happened in other economic activities, the mining and minerals industry has come under tremendous pressure to improve its social, developmental, and environmental performance. Mining, refining, and the use and disposal of minerals have in some instances led to significant local environmental and social damage. Nowadays, like in other parts of the corporate world, companies are more routinely expected to perform to ever higher standards of behavior, going well beyond achieving the best rate of return for shareholders. They are also increasingly being asked to be more transparent and subject to third-party audit or review, especially in environmental aspects. In terms of environment, there are three inter-related areas where innovation and new business models can make the biggest difference: carbon, water and biodiversity. The focus in these three areas is for two reasons. First, the industrial and energetic minerals industry has significant footprints in each of these areas. Second, these three areas are where the potential environmental impacts go beyond local stakeholders and communities, and can even have global impacts, like in the case of carbon. So prioritizing efforts in these areas will ultimately be a strategic differentiator as the industry businesses continues to grow. Over the next forty years, world?s population is predicted to rise from 6.300 million to 9.500 million people. This will mean a huge demand of natural resources. Indeed, consumption rates are such that current demand for raw materials will probably soon exceed the planet?s capacity. As awareness of the actual situation grows, the public is demanding goods and services that are even more environmentally sustainable. This means that massive efforts are required to reduce the amount of materials we use, including freshwater, minerals and oil, biodiversity, and marine resources. It?s clear that business as usual is no longer possible. Today, companies face not only the economic fallout of the financial crisis; they face the substantial challenge of transitioning to a low-carbon economy that is constrained by dwindling natural resources easily accessible. Innovative business models offer pioneering companies an early start toward the future. They can signal to consumers how to make sustainable choices and provide reward for both the consumer and the shareholder. Climate change and carbon remain major risk discontinuities that we need to better understand and deal with. In the absence of a global carbon solution, the principal objective of any individual country should be to reduce its global carbon emissions by encouraging conservation. The mineral industry internal response is to continue to focus on reducing the energy intensity of our existing operations through energy efficiency and the progressive introduction of new technology. Planning of the new projects must ensure that their energy footprint is minimal from the start. These actions will increase the long term resilience of the business to uncertain energy and carbon markets. This focus, combined with a strong demand for skills in this strategic area for the future requires an appropriate change in initial and continuing training of engineers and technicians and their awareness of the issue of eco-design. It will also need the development of measurement tools for consistent comparisons between companies and the assessments integration of the carbon footprint of mining equipments and services in a comprehensive impact study on the sustainable development of the Economy.