Study of Gas Tracers for CO2 monitoring

AbstractGas tracers have been tested for monitoring and detecting CO2 displacement in the underground and eventually leakages to the upper layers in geological storage sites. Commonly used tracers are perfluorocarbons (PFCs) and sulfur hexafluoride (SF6). In Brazil, we are carrying out gas tracers studies in laboratory for further application in field test facilities. These experiments consist of injecting CO2 with perfluorocarbon (perfluoropropane – PP and perfluormethylcyclopentane – PMCP) at low pressure (ca. 290 psi) in pressurized vessels with different types of sediments and soil samples. After flowing through the sample pores, the tracer is adsorbed into a capillary adsorption tube (CAT) with a specific fiber for perfluorcabon. Then, the tracer is extracted from the CAT through a Thermal Desorption System and subsequently analyzed in a Gas Chromatograph with an Electron Capture Detector (GC -ECD). The objective of these experiments is to evaluate the PFCs as a monitoring tool, analyzing the tracer retention times in different sediments, as well as understanding the CATs adsorption capacity and performance. After laboratory tests, field experiments will be conducted in the course of this project. Several experiments of CO2 injection and controlled leaks will be developed in shallow vertical wells at the project site as a continuity of the experiments started at Ressacada Farm Site (Florianópolis, Brazil). The project aim is to understand the flow and dispersion of CO2 in soil and atmosphere simulating an eventual leakage from a geological reservoir using an automated system with a dedicated module for tracers injection into CO2 stream

Desenvolvimento de sistema de teste laboratorial e metodologia para cromatografia gasosa acoplada a dessorvedor t?rmico e uso do octafluoropropano como tra?ador gasoso para o CO2

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS ([email protected]) on 2016-08-24T17:21:53Z No. of bitstreams: 1 DIS_MARCELO_JARDIM_CONSTANT_COMPLETO.pdf: 3807363 bytes, checksum: 6921af716e8d8e0e50af37940efce439 (MD5)Made available in DSpace on 2016-08-24T17:21:53Z (GMT). No. of bitstreams: 1 DIS_MARCELO_JARDIM_CONSTANT_COMPLETO.pdf: 3807363 bytes, checksum: 6921af716e8d8e0e50af37940efce439 (MD5) Previous issue date: 2015-11-30Gas tracers are widely used to control effects in various areas of research, but its implementation has yet to be proven specifically in the case of CO2 monitoring in geological storage sites, so that the gas percolation system is designed to test the feasibility the use of gas tracers as indicators of CO2 in geological storage of carbon projects. The tracer gas injection system is a set of stainless steel connections, which occurs percolation of the tracer gas (octafluoropropane), mixed with carbon dioxide within a porous structure bench simulating the migration of this gas in the assembly. The gaseous tracers are markers that allow information about the migration of CO2 in porous media. Perfluorocarbons are gas tracers used in CO2 storage experiments. The octafluoropropane (C3F8) is a nonflammable fluorocarbon is commonly used in the semiconductor industry, but here in this paper was tested as a tracer for CO2. The bench injection system for gaseous tracer test was presented as a tool for a preliminary understanding of C3F8 tracer gas for CO2. The gases in the study were injected into a tube containing a porous medium, medium sand, to test the marker function of C3F8. Different injection times were tested and collected in thermal desorption tubes (CATs). The gas outlet of this tube were collected and analyzed by gas chromatography with an electron capture detector (ECD) coupled to a heat Desorption. Both C3F8 as CO2 were detected in all experiments indicating the possibility of C3F8 have passed through the porous medium with the CO2. The findings of this study and suggestions made based on it will help in further work related to the monitoring of CO2 and geological storage of carbon.Tra?adores de g?s s?o amplamente utilizados para efeitos de controle em v?rias ?reas de investiga??o, mas sua implementa??o ainda precisa ser comprovada especificamente no caso de monitoriza??o de CO2 em locais de armazenamento geol?gico, para isso o sistema de percola??o de gases foi desenvolvido para testar a viabilidade do uso de tra?adores gasosos como indicadores de CO2 em projetos de armazenamento geol?gico de carbono. O sistema de inje??o de tra?adores gasosos ? um conjunto de conex?es de a?o inox onde ocorre a percola??o do tra?ador gasoso (octafluoropropano) misturado ao di?xido de carbono, por dentro de uma estrutura porosa, simulando em bancada a migra??o desse g?s no conjunto. Os tra?adores gasosos s?o marcadores que permitem obter informa??es sobre a migra??o do CO2 em meios porosos. Os perfluorocarbonos s?o tra?adores gasosos utilizados em experimentos de armazenamento de CO2. O octafluoropropano (C3F8) ? um fluorocarbono n?o inflam?vel ? comumente utilizado na ind?stria em semicondutores, mas aqui neste trabalho foi testado como um tra?ador para o CO2. O sistema de inje??o de bancada para teste de tra?adores gasosos se apresentou como uma ferramenta para uma compreens?o preliminar do g?s marcador C3F8 para o CO2. Os gases no estudo foram injetados em um tubo que continha um meio poroso, areia de granulometria m?dia, para testar a fun??o marcadora do C3F8. Diferentes tempos de inje??o foram testados e coletados em tubos de dessor??o t?rmica (CATs). Os gases de sa?da desse tubo foram coletados e analisados por cromatografia gasosa com um detector de captura de el?trons (ECD) acoplado a um dessorvedor t?rmico. Tanto o C3F8 quanto o CO2 foram detectados em todos os experimentos, indicando a possibilidade do C3F8 ter atravessado o meio poroso junto ao CO2. As conclus?es desse trabalho e as sugest?es feitas baseadas nele auxiliar?o em novos trabalhos relacionados com o monitoramento do CO2 e armazenamento geol?gico de carbono

Proposition de campagne à la mer, Flotte Océanographique Française, Appel d'offre 2018 : Multi-disciplinary investigation of fluid venting from gas hydrate system in the Nile deep-sea fan (SEAGAL)

Prioritaire 1 - voir rapport d'évaluation (https://www.flotteoceanographique.fr/content/download/29325/199063/file/CR-CNFH-novembre-2016-V12.pdf)La campagne SEAGAL est demandée sur la marge nilotique à bord du NO Marion Dufresne par l’UMR Géoazur en collaboration avec des partenaires français (Universités de Nice Sophia Antipolis, UPMC et Université Bordeaux1, Ifremer), Brésiliens (PUCRS-IPR), Allemands (Jacobs University Bremen), Italiens (OGS) et Egyptiens (Université d’Alexandrie). Elle est basée sur des résultats/hypothèses touchant aux interactions entre les glissements sous-marins à grande échelle et la circulation/échappement de fluides et gaz, dans le contexte de l'évolution de la stabilité des hydrates de gaz au cours des cycles climatiques glaciaires-interglaciaires. SEAGAL propose une étude pluridisciplinaire (géophysique, géologique, géochimique, géotechnique et géothermique) de zones d’intérêt de la Province Centrale du delta profond du Nil afin de :(1) Etudier la nature et l'origine des structures de cheminées gazeuses qui sont enracinées dans la zone de stabilité d’hydrates de gaz (GHSZ) et qui émettent du gaz vers les océans par le biais de pockmarks. En particuliers, il s’agira de tester les modèles proposés pour ces cheminées qui se formeraient soit par la remontée de fluides salés et tièdes et provoqueraient l’amincissement de la zone de stabilité des hydrates, soit par l’expulsion rapide du sel contenu dans les eaux interstitielles par un flux rapide de gaz et qui permettrait la formation d’hydrates. Ceci sera abordé par le prélèvement de longues carottes Calypso, de mesures Penfeld et de flux de chaleur le long de transects recoupant des pockmarks afin de caractériser la composition des fluides interstitiels, les flux verticaux et horizontaux de fluides en relation avec la distribution des hydrates de gaz. Cette approche permettra de tester les modèles existants de fonctionnement des conduits issus de la zone de stabilité des hydrates de gaz et de proposer éventuellement un modèle alternatif, applicable à d’autres zones géographiques.(2) Comprendre l’impact des circulations de fluides associées aux pockmarks sur la couverture sédimentaire superficielle et son fluage progressif. Il s’agira de quantifier l’état de stabilité de la pente continentale et de mieux contraindre l’interaction fluides-sédiments sur le déclenchement des instabilités sédimentaires en associant pour la première fois sur cette marge l’acquisition de données Penfeld et de carottes longues pour analyser le comportement rhéologique des matériaux dans les zones affectées par les fluides et la déformation et dans les zones non affectées.(3) Tester l’hypothèse selon laquelle la dissociation des hydrates de gaz serait responsable des glissements géants (10-1000 km3) sur les marges continentales, en particulier la série de MTDs identifiés à la limite entre les Provinces centrale et occidentale de la marge nilotique au cours des derniers 115 kyrs. La marge nilotique est en effet l’une des zones les plus favorables au monde pour contraindre l’impact de la dissociation des hydrates de gaz sur le déclenchement de glissements, car la Méditerranée a connu des augmentations de la température des eaux de fond qui ont dû réduire le domaine de stabilité des hydrates de gaz à l’échelle de bassin, provoquant alors une augmentation des pressions interstitielles sur de grandes zones. L’un des objectifs de SEAGAL est donc d’obtenir pour la première fois sur la marge nilotique une estimation des variations de la température des eaux de fond à partir d’analyses Ca/Mg réalisées sur des foraminifères benthiques afin de pouvoir modéliser les changements induits sur la zone de stabilité des hydrates au cours des derniers 115 kyrs et comparer les périodes de dissociation des hydrates avec les âges des MTDs.La demande de campagne SEAGAL s’appuie sur l’expérience des équipes scientifiques françaises en Méditerranée orientale, acquise depuis 1998 dans le cadre de programmes nationaux et européens. SEAGAL s’appuie sur le projet européen SEAGAS (2016-2019), une collaboration franco-brésilienne étudiant la dynamique des hydrates de gaz sur les marges du Nil et de l’Amazone.The SEAGAL campaign of the RV Marion Dufresne to the Nile deep-sea fan is proposed by UMR Geoazur in collaboration with partners from France (Universities of Nice Sophia Antipolis, UPMC and Bordeaux1, Ifremer), Brazil (IPR-PUCRS), Germany (Jacobs University Bremen), Italy (OGS) and Egypt (University of Alexandria). The campaign proposal builds on previous investigations of the interactions of large-scale sediment failure with fluid flow and gas venting, in the context of changing gas hydrate stability during glacial-interglacial cycles of climate. SEAGAL proposes a multidisciplinary study (geophysical, geological, geochemical geotechnical and geothermal) of targets in the central province of the Nile fan, to address three main objectives:(1) To investigate the nature and origin of chimney-like structures within the gas hydrate stability zone (GHSZ) that are venting gas to the oceans through seabed pockmarks, in particular to test proposed models in which they form by the rise of hot and/or saline fluids to thin the GHSZ, versus a mechanism of salt exclusion that links the basal phase boundary to seabed. This will be achieved through the acquisition along transects across selected features of measurements up to 40 m below seabed, including Calypso cores, penetrometer data and geothermal measurements, in order to identify composition of pore fluids and gases, and to characterise vertical and horizontal fluxes of fluids and heat in relation to the distribution of gas hydrates and carbonates. The results will be applied to modelling of gas hydrate stability to test proposed models for chimney formation, or to propose a new model. We will also acquire multibeam water column data to examine spatial and temporal variations in gas flux from pockmarks on the central Nile fan since the 2011 APINIL campaign.(2) To examine the relation of fluid circulation to processes of downslope creep of the sediment cover above buried mass transport deposits (MTDs). This will be achieved by the first ever acquisition of transects of penetrometer data and Calypso cores up to 40 m long from wave-like deformation features and subjacent MTDs, in order to characterise the mechanical properties of sediments and bounding faults in relation to the distribution of carbonates and flux of fluids. The results will be used as original input to geotechnical modelling of mass failure and post-failure processes, in order to constrain the triggering factors of failure and their potential consequences (e.g. tsunamis).(3) To test the relation between gas hydrate stability changes and large submarine landslides, in particular to a series of MTDs on the western edge of the central Nile province dated to the last 115 ka. The Nile fan is one of the best places in the world to test the hypothesis that gas hydrate dissociation can trigger sediment failures, due to basin-wide changes in Mediterranean bottom water temperatures (bwts) of up to 4 ̊ C that drove large changes in the GHSZ at all water depths below c. 1000 m. This will be done using Mg/ Ca paleotemperature data from benthic foraminifera in sediment cores to reconstruct the history of bwt changes, as input to modelling of GHSZ changes in response to both temperature and sea level variations over last 115 ka, allowing accurate comparison of periods of gas hydrate dissociation to the ages of 11 giant MTDs.The SEAGAL proposal builds on French-led international investigations of the eastern Mediterranean Sea since 1998, undertaken in the context of national and European projects. SEAGAL is linked to the EC-funded project SEAGAS (2016-2019), a French-Brazilian collaboration coordinated by Géoazur to investigate gashydrate dynamics on the Mediterranean and Brazilian margins, inspired by the 2011 APINIL campaign and intended to lead to future trans-Atlantic research projects