subject:(Gas hydrates)

University of Texas – Austin

1. -1522-4192. Pore size distribution and methane equilibrium conditions at Walker Ridge Block 313, northern Gulf of Mexico.

Degree: MSin Engineering, Petroleum engineering, 2016, University of Texas – Austin

URL: http://hdl.handle.net/2152/38192

► In-situ pressure, temperature, salinity and pore size may allow coexistence of three methane phases: liquid (L), gas (G), hydrate (H) in marine gas hydrate systems.… (more)

▼ In-situ pressure, temperature, salinity and pore size may allow coexistence of three methane phases: liquid (L), gas (G), hydrate (H) in marine gas hydrate systems. A discrete zone of three-phase equilibrium may occur near the base of the gas hydrate stability zone (GHSZ) in sediments with salinity close to seawater due to capillary effects. The existence of a three-phase zone affects the location of the bottom-simulating reflection (BSR) and also has repercussions for methane fluxes at the base of the GHSZ. This project studied the hydrate stability conditions in two wells, WR313-G and WR313-H, at Walker Ridge Block 313 in the northern Gulf of Mexico. The pore size distributions were determined by constructing a synthetic nuclear magnetic resonance (NMR) relaxation time distribution. Correlations were obtained by non-linear regression on NMR, gamma ray, and bulk density logs from well KC-151 at Keathley Canyon. The correlations enabled construction of relaxation time distributions for WR313-G and WR313-H, which were used to predict pore size distribution through comparison with mercury injection capillary pressure measurements. With the computed pore size distribution, L+H and L+G methane solubility was determined from in-situ pressure and temperature. The intersection of the L+G and L+H curves for various pore sizes allowed calculation of the depth range of the three-phase equilibrium zone. In previous studies at Blake Ridge and Hydrate Ridge, the top of the three-phase zone moves upwards with increasing water depth and overlies the bulk three-phase equilibrium depth but this was not observed at Walker Ridge. In clays at Walker Ridge, the predicted thickness of the three-phase zone is approximately 5 m, but in coarse sands it is only a few centimeters due to the difference in absolute pore sizes and the width of the pore size distribution. The thick three-phase zone in the clays may explain in part why the BSR is only observed in the sand layers at Walker Ridge, although other factors may influence the presence or absence of a BSR. Advisors/Committee Members: Daigle, Hugh (advisor), Okuno, Ryosuke (committee member).

Subjects/Keywords: Gas hydrates; Methane hydrates

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APA (6^th Edition):

-1522-4192. (2016). Pore size distribution and methane equilibrium conditions at Walker Ridge Block 313, northern Gulf of Mexico. (Masters Thesis). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/38192

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Chicago Manual of Style (16^th Edition):

-1522-4192. “Pore size distribution and methane equilibrium conditions at Walker Ridge Block 313, northern Gulf of Mexico.” 2016. Masters Thesis, University of Texas – Austin. Accessed January 27, 2021. http://hdl.handle.net/2152/38192.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

MLA Handbook (7^th Edition):

-1522-4192. “Pore size distribution and methane equilibrium conditions at Walker Ridge Block 313, northern Gulf of Mexico.” 2016. Web. 27 Jan 2021.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Vancouver:

-1522-4192. Pore size distribution and methane equilibrium conditions at Walker Ridge Block 313, northern Gulf of Mexico. [Internet] [Masters thesis]. University of Texas – Austin; 2016. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/2152/38192.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Council of Science Editors:

-1522-4192. Pore size distribution and methane equilibrium conditions at Walker Ridge Block 313, northern Gulf of Mexico. [Masters Thesis]. University of Texas – Austin; 2016. Available from: http://hdl.handle.net/2152/38192

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Louisiana State University

2. Dhakal, Sulav. Thermogenic Gas Hydrate Formation In Gulf of Mexico Offshore Environment- Results from Numerical Simulation.

Degree: MSPE, Petroleum Engineering, 2018, Louisiana State University

URL: https://digitalcommons.lsu.edu/gradschool_theses/4669

► Development of civilization and the resulting quest for energy have led us to previously uncharted territory in exploration and production of fuel. As the… (more)

▼ Development of civilization and the resulting quest for energy have led us to previously uncharted territory in exploration and production of fuel. As the demand continues to grow and conventional oil reserves become depleted, we are looking into unconventional resources such as gas hydrates. However, due to the volatile nature of the energy market and production technology yet to perfected, we are not able to fully utilize the potential of gas hydrates yet. Reservoir characterization of hydrates have so far been limited to seismic mapping, well log interpretation and laboratory scale studies. This research uses numerical simulation to understand the geological and thermodynamic setting in which methane hydrates form in the subsurface and the reservoir quality changes that occur during and after the formation of hydrates. A reservoir model with sand and shale layers with a fault running through them is generated and flow of thermogenic methane gas as seen in the Gulf of Mexico subsurface is simulated using TOUGH+HYDRATE, a numerical code developed at the Lawrence Berkeley National Laboratory. The code uses an integrated finite difference method for space and time discretization to simulate multiphase flow in a geological system. The model was created using a specific MATLAB code for this research. Sensitivities on boundary conditions, fault angles, flow rate and reservoir properties are performed to study the formation process of methane hydrates. The simulation results show that the hydrate formation depends on the reservoir rock and flow parameters. The geobody distribution of hydrate was highly affected by permeability, stratigraphy, fault angles and the boundary conditions, whereas, the saturation was impacted by pore-water salinity and flow rate of the gas into the reservoir. Numerical simulation of hydrate formation and the study of the reservoir properties are an important aspect of reservoir characterization for hydrates, which can be used for production planning of methane gas from these reserves. A more robust numerical code must be developed for a reservoir scale modeling of hydrate formation to simulate detailed complexities.

Subjects/Keywords: gas hydrates; methane hydrates; reservoir characterization

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APA (6^th Edition):

Dhakal, S. (2018). Thermogenic Gas Hydrate Formation In Gulf of Mexico Offshore Environment- Results from Numerical Simulation. (Masters Thesis). Louisiana State University. Retrieved from https://digitalcommons.lsu.edu/gradschool_theses/4669

Chicago Manual of Style (16^th Edition):

Dhakal, Sulav. “Thermogenic Gas Hydrate Formation In Gulf of Mexico Offshore Environment- Results from Numerical Simulation.” 2018. Masters Thesis, Louisiana State University. Accessed January 27, 2021. https://digitalcommons.lsu.edu/gradschool_theses/4669.

MLA Handbook (7^th Edition):

Dhakal, Sulav. “Thermogenic Gas Hydrate Formation In Gulf of Mexico Offshore Environment- Results from Numerical Simulation.” 2018. Web. 27 Jan 2021.

Vancouver:

Dhakal S. Thermogenic Gas Hydrate Formation In Gulf of Mexico Offshore Environment- Results from Numerical Simulation. [Internet] [Masters thesis]. Louisiana State University; 2018. [cited 2021 Jan 27]. Available from: https://digitalcommons.lsu.edu/gradschool_theses/4669.

Council of Science Editors:

Dhakal S. Thermogenic Gas Hydrate Formation In Gulf of Mexico Offshore Environment- Results from Numerical Simulation. [Masters Thesis]. Louisiana State University; 2018. Available from: https://digitalcommons.lsu.edu/gradschool_theses/4669

Oregon State University

3. Rose, Kelly Kathleen. Signatures in the Subsurface - Big & Small Data Approaches for the Spatio-Temporal Analysis of Geologic Properties & Uncertainty Reduction.

Degree: PhD, Geology, 2016, Oregon State University

URL: http://hdl.handle.net/1957/59459

► Despite more than two centuries of exploration, including more than six million deep wellbores with depths exceeding 40,000 feet in some parts of the world,… (more)

▼ Despite more than two centuries of exploration, including more than six million deep wellbores with depths exceeding 40,000 feet in some parts of the world, our ability to constrain subsurface processes and properties remains limited. Characteristics of the subsurface vary and can be analyzed on a variety of spatial scales. Characterization and prediction of subsurface properties, such as depth, thickness, porosity, permeability, pressure and temperature, are important for models and interpretations of the subsurface. Subsurface studies contribute to insights and understanding of natural system but also enable predictions and assessments of subsurface resources (water, heat, hydrocarbon, mineral, storage capacity) and support environmental and geohazard assessments. However, the availability of data to characterize these systems as well as the techniques that utilize those data vary significantly. There is a wealth of data and information in structured and unstructured datasets stemming from subsurface characterization and interpretation studies. In addition, the geo-data science landscape is shifting, becoming more open. This affords opportunities to fill knowledge gaps, mine large, interrelated datasets, and develop innovative methods to improve our understanding of the subsurface and the impacts of its exploration. This study demonstrates different approaches, at a range of scales, for evaluating subsurface properties using a combination of “small” and “big” data approaches. In particular, focusing on wellbore data which can be used to investigate questions at the individual well or the global scale. Wellbore related datasets, such as those associated with India’s NGHP-01 Site 17A, are the primary source of direct subsurface measurements. In this work, small-scale analyses from a single wellbore were used to establish that diagenetic mineralization is responsible for anomalous porosity preservation and enhanced permeability in sediments from NGHP-01 Site 17A. This relationship explains and further constrains how geologic history and architecture influences gas hydrate distribution both within the lithostratigraphic record at NGHP-01 Site 17A and in other sedimentary settings worldwide. In addition, collections of wellbore data are increasingly used in spatial statistical analyses to improve prediction of subsurface properties at the field to basin-scale. These analyses typically have disregarded contextual geologic information because of its complex and unstructured format. This results in the loss of valuable information. This study presents a structured, hybrid deductive-probabilistic approach that integrates both contextual geologic information with quantitative analytical tools to improve prediction of subsurface properties and reduce uncertainty. The Subsurface Trend Analysis approach is demonstrated and validated in the prediction of subsurface pressure for the north-central region of the Gulf of Mexico. Finally, this study assembles and presents together information for the global… Advisors/Committee Members: Meigs, Andrew (advisor), Torres, Marta (committee member).

Subjects/Keywords: hydrate; Natural gas – Hydrates

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APA (6^th Edition):

Rose, K. K. (2016). Signatures in the Subsurface - Big & Small Data Approaches for the Spatio-Temporal Analysis of Geologic Properties & Uncertainty Reduction. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/59459

Chicago Manual of Style (16^th Edition):

Rose, Kelly Kathleen. “Signatures in the Subsurface - Big & Small Data Approaches for the Spatio-Temporal Analysis of Geologic Properties & Uncertainty Reduction.” 2016. Doctoral Dissertation, Oregon State University. Accessed January 27, 2021. http://hdl.handle.net/1957/59459.

MLA Handbook (7^th Edition):

Rose, Kelly Kathleen. “Signatures in the Subsurface - Big & Small Data Approaches for the Spatio-Temporal Analysis of Geologic Properties & Uncertainty Reduction.” 2016. Web. 27 Jan 2021.

Vancouver:

Rose KK. Signatures in the Subsurface - Big & Small Data Approaches for the Spatio-Temporal Analysis of Geologic Properties & Uncertainty Reduction. [Internet] [Doctoral dissertation]. Oregon State University; 2016. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/1957/59459.

Council of Science Editors:

Rose KK. Signatures in the Subsurface - Big & Small Data Approaches for the Spatio-Temporal Analysis of Geologic Properties & Uncertainty Reduction. [Doctoral Dissertation]. Oregon State University; 2016. Available from: http://hdl.handle.net/1957/59459

Delft University of Technology

4. He, Y. Formation of Methane and Carbon Dioxide Hydrates in Bulk and in Porous Media.

Degree: 2012, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; urn:NBN:nl:ui:24-uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; urn:NBN:nl:ui:24-uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; http://resolver.tudelft.nl/uuid:0efcef4e-0945-42e0-9a9b-df515492504a

► Gashydraatvorming is een kristallisatieproces. Dit proces bestaat uit twee fases, respectievelijk nucleatie (de vorming van nucleatie kernen) en hydraatgroei (degroei van kleine nucleatiekernen tot grote… (more)

▼ Gashydraatvorming is een kristallisatieproces. Dit proces bestaat uit twee fases, respectievelijk nucleatie (de vorming van nucleatie kernen) en hydraatgroei (degroei van kleine nucleatiekernen tot grote hydraatkristallen). Deze twee fases van het kristallisatieproces worden in het binaire systeem gekenmerkt door de nucleatietijd en de halfwaardetijd. De resultaten laten een afname zien in nucleatietijd naar mate oververzadiging en roersnelheid toenemen. Bovendien vermindert de nucleatietijd als gevolg van het geheugeneffect wanneer de experimenten worden uitgevoerd met `gebruikt' water. Dit geheugeneffect is beschreven door andere auteurs [98, 149] en kan worden verklaard door het bestaan van (water) hydraatstructuren na dissociatie van gashydraten. De structurering van de water-moleculen is waarschijnlijk gewaarborgd door de overvloed aan waterstofbruggen in de waterfase bij lage temperaturen door de aanwezigheid van opgeloste gastmoleculen. De tweede fase, de daadwerkelijke groei van gashydraten, bleek ongevoelig te zijn voor veranderingen in de mate van oververzadiging. De groei neemt toe met een verhoging van de roersnelheid; echter, het geheugeneffect van water heeft een licht negatief effect op de groei van het gashydraat. Daarom is niet nucleatie, maar kristalgroei de snelheidslimiterende stap tijdens gashydraatvorming. Uit experimenten in het binaire systeem bleek ook, dat, bij gelijke mate van oververzadiging, de kristalgroei van CO2 hydraten sneller is dan van CH4 hydraten. Dit wijst er op dat, kinetisch gezien, de vorming van CO2 hydraten gunsitiger is dan de vorming van CH4 hydraten. Bevindingen resulterend van experimenten in het ternaire systeem ondersteunen deze theorie. In het ternaire systeem blijken bij iedere geteste initiele druk CO2 moleculen makkelijker te vangen in kooien van watermoleculen dan CH4 moleculen (Hoofdstuk 4). Ondanks dat de CH4 concentratie in de gevormde gashydraten toeneemt met de initiele druk, bevatten de ontstane gashydraten nog steeds meer CO2 dan CH4. De formatie van methaanhydraat bij lage druk (lager dan de evenwichtsdruk van de H - Lw - V curve voor het CH4 + H2O systeem) wordt bevestigd. Dit betekent dat de aanwezigheid van een `makkelijkere' gashydraatvormer, zoals CO2, er voor kan zorgen dat de CH4 hydraat wordt gestabiliseerd. Experimenten, waarbij van een gasmix van 50/50 CH4/CO2 gashydraten worden gevormd, lieten zien dat de hoogste CH4 en CO2 scheidings effcientie wordt behaald bij een druk lager dan 3.5 MPa. Hierbij wordt in de gasfase een verandering van 18% van de initiele CH4 molfractie gevonden. Bulkexperimenten hebben tastbaar bewijs geleverd dat CH4 in de al gevormde methaanhydraten kan worden uitgewisseld met CO2 zonder dat er dissociatie van de gashydraten optreedt (Hoofdstuk 4). Echter, de vervanging vindt plaats op een zeer geringe diepte, vlakbij het scheidingsvlak tussen de gasfase en de gashydraten. Hierdoor functioneren CO2-rijke hydraatlagen als een schild en belemmeren verdere penetratie van CO2 in dieper gelegen methaanhydraatlagen en werken de… Advisors/Committee Members: Zitha, P.L.J..

Subjects/Keywords: gas hydrates

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APA (6^th Edition):

He, Y. (2012). Formation of Methane and Carbon Dioxide Hydrates in Bulk and in Porous Media. (Doctoral Dissertation). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; urn:NBN:nl:ui:24-uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; urn:NBN:nl:ui:24-uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; http://resolver.tudelft.nl/uuid:0efcef4e-0945-42e0-9a9b-df515492504a

Chicago Manual of Style (16^th Edition):

He, Y. “Formation of Methane and Carbon Dioxide Hydrates in Bulk and in Porous Media.” 2012. Doctoral Dissertation, Delft University of Technology. Accessed January 27, 2021. http://resolver.tudelft.nl/uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; urn:NBN:nl:ui:24-uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; urn:NBN:nl:ui:24-uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; http://resolver.tudelft.nl/uuid:0efcef4e-0945-42e0-9a9b-df515492504a.

MLA Handbook (7^th Edition):

He, Y. “Formation of Methane and Carbon Dioxide Hydrates in Bulk and in Porous Media.” 2012. Web. 27 Jan 2021.

Vancouver:

He Y. Formation of Methane and Carbon Dioxide Hydrates in Bulk and in Porous Media. [Internet] [Doctoral dissertation]. Delft University of Technology; 2012. [cited 2021 Jan 27]. Available from: http://resolver.tudelft.nl/uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; urn:NBN:nl:ui:24-uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; urn:NBN:nl:ui:24-uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; http://resolver.tudelft.nl/uuid:0efcef4e-0945-42e0-9a9b-df515492504a.

Council of Science Editors:

He Y. Formation of Methane and Carbon Dioxide Hydrates in Bulk and in Porous Media. [Doctoral Dissertation]. Delft University of Technology; 2012. Available from: http://resolver.tudelft.nl/uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; urn:NBN:nl:ui:24-uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; urn:NBN:nl:ui:24-uuid:0efcef4e-0945-42e0-9a9b-df515492504a ; http://resolver.tudelft.nl/uuid:0efcef4e-0945-42e0-9a9b-df515492504a

Colorado School of Mines

5. Grasso, Giovanny A. Investigation of hydrate formation and transportability in mutiphase flow systems.

Degree: PhD, Chemical and Biological Engineering, 2015, Colorado School of Mines

URL: http://hdl.handle.net/11124/17094

► The oil and gas industry is moving towards offshore developments in more challenging environments, where evaluating hydrate plugging risks to avoid operational/safety hazards becomes more… (more)

▼ The oil and gas industry is moving towards offshore developments in more challenging environments, where evaluating hydrate plugging risks to avoid operational/safety hazards becomes more difficult (Sloan, 2005). Even though mechanistic models for hydrate plug formation have been developed, components for a full comprehensive model are still missing. Prior to this work, research efforts were focused on flowing hydrate particles with relatively little research on hydrate accumulation, leaving hydrate deposition in multiphase flow an unexplored subject. The focus of this thesis was to better understand hydrate deposition as a form of accumulation in pipelines. To incorporate the multiphase flow effect, hydrate formation experiments were carried out at varying water cut (WC) from 15 to 100 vol.%, liquid loading (LL) from 50 to 85 vol.%, mixture velocity (vmix) from 0.75 to 3 m/s, for three fluids systems (100 % WC, water in Conroe crude oil emulsions and King Ranch condensate + water) on the ExxonMobil flowloop (4 in. nominal size and 314 ft. long) at Friendswood, TX. For the 100 % WC flowloop tests, hydrate particle distribution transitions beyond a critical hydrate volume concentration, observed values were between 8.2 to 29.4 vol.%, causing a sudden increase in pressure drop (DP). A revised correlation of the transition as a function of Reynolds number and liquid loading was developed. For Conroe emulsions, DP starts increasing at higher hydrate concentrations than King Ranch condensate, many times at 10 vol.%. Experiments with King Ranch show higher relative DP (10 to 25) than Conroe (2 to 10) performed at the same vmix and LL. Cohesive force measurements between cyclopentane hydrate particles were reduced from a value of 3.32 mN/m to 1.26 mN/m when 6 wt.% Conroe was used and to 0.41 mN/m when 5 wt.% Caratinga crude oil was used; similar values were obtained when extracted asphaltenes were used. King Ranch condensate (11 wt.%) did not significantly change the cohesion force (3.32 mN/m). These measurements prove the importance of natural surfactants in crude oil for particle dispersion. An experimental methodology was provided to determine the effectiveness of asphaltenes as a dispersant. Even though hydrate deposition was inferred from the flowloop tests, it could not be verified from these measurements . Custom-made experimental set-ups (a recirculation liquid system, a rocking cell and a lab-scale mini-loop) were used to isolate the hydrate deposition investigation. Besides water, mineral oil 70T and King Ranch condensate were used in combination with water for the deposition investigation. One of the most important deliverables of this thesis was the construction of a lab-scale flowloop that provides insight on deposition phenomenon in multiphase flow, representing the only set-up, reported in the literature, suitable for this investigation. The miniloop can handle gas-liquid flow (maximum flow rates of 10 Nm3/m for gas and 22 GPM for liquid) through a 10 ft. long straight section (2 in. standard tubing). The… Advisors/Committee Members: Sum, Amadeu K. (advisor), Lachance, Jason W. (committee member), Liberatore, Matthew W. (committee member), Agarwal, Sumit (committee member), Yin, Xiaolong (committee member).

Subjects/Keywords: film growth; hydrate deposition; hydrate accumulation; gas hydrates; flow assurance; Hydrates; Natural gas – Hydrates; Gas pipelines; Multiphase flow

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Grasso, G. A. (2015). Investigation of hydrate formation and transportability in mutiphase flow systems. (Doctoral Dissertation). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/17094

Chicago Manual of Style (16^th Edition):

Grasso, Giovanny A. “Investigation of hydrate formation and transportability in mutiphase flow systems.” 2015. Doctoral Dissertation, Colorado School of Mines. Accessed January 27, 2021. http://hdl.handle.net/11124/17094.

MLA Handbook (7^th Edition):

Grasso, Giovanny A. “Investigation of hydrate formation and transportability in mutiphase flow systems.” 2015. Web. 27 Jan 2021.

Vancouver:

Grasso GA. Investigation of hydrate formation and transportability in mutiphase flow systems. [Internet] [Doctoral dissertation]. Colorado School of Mines; 2015. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/11124/17094.

Council of Science Editors:

Grasso GA. Investigation of hydrate formation and transportability in mutiphase flow systems. [Doctoral Dissertation]. Colorado School of Mines; 2015. Available from: http://hdl.handle.net/11124/17094

University of Edinburgh

6. Teeratchanan, Pattanasak. First-principles studies of gas hydrates and clathrates under pressure.

Degree: PhD, 2018, University of Edinburgh

URL: http://hdl.handle.net/1842/31359

► Gas hydrates are molecular host-guest mixtures where guest gas species are encapsulated in host water networks. They play an important role in gas storage in… (more)

▼ Gas hydrates are molecular host-guest mixtures where guest gas species are encapsulated in host water networks. They play an important role in gas storage in aqueous environments at relatively low pressures, and their stabilities are determined by weak interactions of the guest species with their respective host water frameworks. Thus, the size and the amount of the guest species vary, depending on the size of the empty space provided by the host water structures. The systems studied here are noble gas (He, Ne, Ar) and diatomic (H2) hydrates. Because of the similarity of the guests' sizes between the noble gases and the di-atomic gases, the noble gas hydrates act as simple models for the di-atomic gas hydrates. For example, He, Ne and H2 have approximately the same size. Density functional theory calculations are used to obtain the ground state formation enthalpies of each gas hydrate, as a function of host network, guest stoichiometry, and pressure. Dispersion effects are investigated by comparing various dispersion corrections in the exchange-correlation functionals (semi-local PBE, semi-empirical D2 pair correction, and non-local density functionals i.e. vdW-DF family). Results show that the predicted stability ranges of various phases agree qualitatively, although having quantitative difference, irrespective of the methods of the dispersion corrections in the exchange-correlation functionals. Additionally, it is shown in gas-water dimer interaction calculations that all DFT dispersion-corrected functionals overbind significantly than the interaction acquired by the coupled-cluster calculations, at the CCSD(T) level, which is commonly accepted to provide the most accurate estimation of the actual interaction energy. This could lead to an overestimation of the stability of the hydrate mixtures. Further study in the gas-water cluster indicates that less overbinding effect is found in the cluster than in the dimer. This implies that the overbinding energy caused by DFT might become less pronounce in the solid phase. Graph invariant topology and a program based on a graph theory are used to assign protons based on the 'ice rule' to fulfill the incomplete experimental structural data such as unknown/unclear positions of protons in the host water lattices. These methods help constructing host water networks for computational calculations. Several configurations of the host water structures are tested. Those configurations having lowest enthalpies are used as the host water networks in this research. Furthermore, the enthalpic spread between the configurations having the highest and the lowest enthalpy in the pure water ice network is very small (about 10 meV per water molecule). Nevertheless, it is still unclear to conclude that this protonic effect is also trivial in the gas-water compound. Therefore, this study also calculates the enthalpies of the gas-water mixtures having various proton configurations in the host water networks. Results indicate that very small enthalpic distributions among the proton configurations…

Subjects/Keywords: 530.4; noble gas hydrates; hydrogen hydrates; DFT; high pressure; clathrates

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Teeratchanan, P. (2018). First-principles studies of gas hydrates and clathrates under pressure. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/31359

Chicago Manual of Style (16^th Edition):

Teeratchanan, Pattanasak. “First-principles studies of gas hydrates and clathrates under pressure.” 2018. Doctoral Dissertation, University of Edinburgh. Accessed January 27, 2021. http://hdl.handle.net/1842/31359.

MLA Handbook (7^th Edition):

Teeratchanan, Pattanasak. “First-principles studies of gas hydrates and clathrates under pressure.” 2018. Web. 27 Jan 2021.

Vancouver:

Teeratchanan P. First-principles studies of gas hydrates and clathrates under pressure. [Internet] [Doctoral dissertation]. University of Edinburgh; 2018. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/1842/31359.

Council of Science Editors:

Teeratchanan P. First-principles studies of gas hydrates and clathrates under pressure. [Doctoral Dissertation]. University of Edinburgh; 2018. Available from: http://hdl.handle.net/1842/31359

University of Ottawa

7. Doshi, Malay. Synthesis of Nitrogen-Containing Carbohydrate Derivatives and Their Use Toward Inhibiting Ice Recrystallization and Gas Hydrate Formation .

Degree: 2016, University of Ottawa

URL: http://hdl.handle.net/10393/34340

► Ice recrystallization during cryopreservation results in cell death and decreased cell viabilities due to cellular damage. This is a significant problem particularly in regenerative medicine… (more)

▼ Ice recrystallization during cryopreservation results in cell death and decreased cell viabilities due to cellular damage. This is a significant problem particularly in regenerative medicine where decreased cell viabilities post-thaw affect the success of the therapy. Given the success of these therapies to treat various diseases, the development of novel cryprotectants which have the ability to inhibit ice recrystallization during freezing and thawing are urgently required. Current cryoprotectant such as dimethyl sulfoxide, is associated with cytotoxicity in the clinical settings and thus are not optimal cryoprotectants. Our laboratory is interested in the rational synthesis of non-cytotoxic small molecules which possess the property of ice recrystallization inhibition (IRI) activity. Previously, the Ben laboratory has demonstrated that simple monosaccharides possess moderate ice recrystallization inhibition activity and that this activity is linked to hydration. The “compatibility” of the carbohydrate within the three-dimensional hydrogen bonded network of water is inversely proportional to its IRI activity. Hydration has previously been directly linked to the stereochemical relationship of individual hydroxyl groups on the carbohydrate. Additionally, it has been proposed that intramolecular hydrogen bond formation and hydrogen bonding cooperativity has a large effect on the water structure thus impacting hydration. Structure-function work has suggested that the presence of an amine as a hydrogen donor at the endocyclic position within the pyranose ring maybe beneficial to IRI activity. Thus, the first part of this thesis describes the synthesis and IRI activity of D-glucose and D-galactose based azasugars and its analogues. These azasugars have replaced the endocyclic ring oxygen with an amine. These azasugars and their analogues were found to possess moderate to potent IRI activity suggesting that hydrogen bond donation may be important for hydration and thus, IRI activity at the endocyclic ring oxygen. During the development of these azasugars, the Ben laboratory developed carbohydrate-based surfactants and hydrogelators possessing unprecedented IRI activity. A potential use of molecules possessing IRI activity is towards the inhibition of gas hydrate formation. Gas hydrates are ice-like solids containing gases within a highly ordered network of water molecules. These gas hydrates tend to accumulate in oil and gas pipelines posing significant dangers as the build-up of solid material leads to blockages in the pipeline reducing flow. Previous work had demonstrated the use of antifreeze proteins possessing potent IRI activity in inhibiting gas hydrate formation. However, their complex structure limits commercial use. Thus, the second part of the thesis describes the use of the azasugars, carbohydrate-based surfactants and hydrogelators in inhibiting gas hydrate formation. The effectiveness of the small molecules is compared to a commercial inhibitor PVP 10. Some of these small molecules were significantly…

Subjects/Keywords: Ice Recrystallization Inhibition; Gas Hydrates; Azasugars; Iminosugars

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APA (6^th Edition):

Doshi, M. (2016). Synthesis of Nitrogen-Containing Carbohydrate Derivatives and Their Use Toward Inhibiting Ice Recrystallization and Gas Hydrate Formation . (Thesis). University of Ottawa. Retrieved from http://hdl.handle.net/10393/34340

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Doshi, Malay. “Synthesis of Nitrogen-Containing Carbohydrate Derivatives and Their Use Toward Inhibiting Ice Recrystallization and Gas Hydrate Formation .” 2016. Thesis, University of Ottawa. Accessed January 27, 2021. http://hdl.handle.net/10393/34340.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Doshi, Malay. “Synthesis of Nitrogen-Containing Carbohydrate Derivatives and Their Use Toward Inhibiting Ice Recrystallization and Gas Hydrate Formation .” 2016. Web. 27 Jan 2021.

Vancouver:

Doshi M. Synthesis of Nitrogen-Containing Carbohydrate Derivatives and Their Use Toward Inhibiting Ice Recrystallization and Gas Hydrate Formation . [Internet] [Thesis]. University of Ottawa; 2016. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/10393/34340.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Doshi M. Synthesis of Nitrogen-Containing Carbohydrate Derivatives and Their Use Toward Inhibiting Ice Recrystallization and Gas Hydrate Formation . [Thesis]. University of Ottawa; 2016. Available from: http://hdl.handle.net/10393/34340

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Colorado School of Mines

8. Mann, Susan L. Vapor-solid equilibrium ratios for structure II natural gas hydrates.

Degree: MS(M.S.), Petroleum Engineering, 2016, Colorado School of Mines

URL: http://hdl.handle.net/11124/170217

Subjects/Keywords: Natural gas – Hydrates.

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APA (6^th Edition):

Mann, S. L. (2016). Vapor-solid equilibrium ratios for structure II natural gas hydrates. (Masters Thesis). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/170217

Chicago Manual of Style (16^th Edition):

Mann, Susan L. “Vapor-solid equilibrium ratios for structure II natural gas hydrates.” 2016. Masters Thesis, Colorado School of Mines. Accessed January 27, 2021. http://hdl.handle.net/11124/170217.

MLA Handbook (7^th Edition):

Mann, Susan L. “Vapor-solid equilibrium ratios for structure II natural gas hydrates.” 2016. Web. 27 Jan 2021.

Vancouver:

Mann SL. Vapor-solid equilibrium ratios for structure II natural gas hydrates. [Internet] [Masters thesis]. Colorado School of Mines; 2016. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/11124/170217.

Council of Science Editors:

Mann SL. Vapor-solid equilibrium ratios for structure II natural gas hydrates. [Masters Thesis]. Colorado School of Mines; 2016. Available from: http://hdl.handle.net/11124/170217

Rice University

9. Ahmed, Wael. A Systematic Study of Short and Long Range Interactions in Associating Fluids Using Molecular Theory.

Degree: PhD, Engineering, 2015, Rice University

URL: http://hdl.handle.net/1911/87693

► Parameters needed for the Statistical Associating Fluid Theory (SAFT) equation of state are usually fit to pure component saturated liquid density and vapor pressure. In… (more)

▼ Parameters needed for the Statistical Associating Fluid Theory (SAFT) equation of state are usually fit to pure component saturated liquid density and vapor pressure. In this thesis, other sources of information such as quantum mechanics, infinite dilution properties, Fourier transform infrared (FT-IR) spectroscopy and molecular dynamic (MD) simulation are used to obtain a unique set of parameters for complex fluids such as water and alcohols. Consequently, the equation of state can be more predictive and the parameters are not anymore system dependent. Moreover, the four vertices of the molecular thermodynamic tetrahedron (phase equilibrium experiments, spectroscopy, MD simulation and molecular theory) are used to study the distribution of hydrogen bonds in water and alcohol containing mixtures. The new sets of physical parameters and the knowledge gained in studying hydrogen bonding are then applied to model water content of sour natural gas mixtures as well as the phase behavior of alcohol + n-alkane and alcohol + water binary systems. Accurate determination of the water content in hydrocarbons is critical for the petroleum industry due to corrosion and hydrate formation problems. Experimental data available in the literature on the water content of n-alkanes (C5 and higher) is widely scattered. The perturbed chain form of the SAFT equation of state (PC-SAFT) was used to accurately correlate water mole fraction in n-alkanes, C1 to C16, which are in equilibrium with liquid water or ice. In addition, a list of experimental data is recommended to the reader based on its agreement with the fundamental equation of state used in this dissertation. The proposed molecular model was then applied to predict water content of pure carbon dioxide (CO2), hydrogen sulfide (H2S), nitrous oxide (N2O), nitrogen (N2) and argon (Ar) systems. The theory application was also extended to model water content of acid gas containing mixtures in equilibrium with an aqueous or a hydrate phase. To model accurately the liquid-liquid equilibrium (LLE) at subcritical conditions, cross association between CO2, H2S and water was included. The hydrate phase was modeled using a modified van der Waals and Platteeuw (vdWP) theory. The agreement between the model predictions and experimental data measured in our lab was found to be good across a wide range of temperatures and pressures. Modeling the phase behavior of liquid water can be quite challenging due to the formation of complex hydrogen bonding network structures at low temperatures. However, alcohols share some similarities with water in terms of structure and physical interactions. As a result, studying alcohol + n-alkane binary systems can provide us with a better understanding of water-alkane interactions. Besides, the application of alcohols in the petroleum and the biodiesel industry is of great importance. As a result, Polar PC-SAFT was used to model short chain 1- alcohol + n-alkane mixtures. The ability of the equation of state to predict accurate activity coefficients at… Advisors/Committee Members: Chapman, Walter G (advisor), Cox, Kenneth R (committee member), Tomson, Mason B (committee member), Biswal, Sibani L (committee member).

Subjects/Keywords: SAFT; water content; gas hydrates; hydrogen bonding

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ahmed, W. (2015). A Systematic Study of Short and Long Range Interactions in Associating Fluids Using Molecular Theory. (Doctoral Dissertation). Rice University. Retrieved from http://hdl.handle.net/1911/87693

Chicago Manual of Style (16^th Edition):

Ahmed, Wael. “A Systematic Study of Short and Long Range Interactions in Associating Fluids Using Molecular Theory.” 2015. Doctoral Dissertation, Rice University. Accessed January 27, 2021. http://hdl.handle.net/1911/87693.

MLA Handbook (7^th Edition):

Ahmed, Wael. “A Systematic Study of Short and Long Range Interactions in Associating Fluids Using Molecular Theory.” 2015. Web. 27 Jan 2021.

Vancouver:

Ahmed W. A Systematic Study of Short and Long Range Interactions in Associating Fluids Using Molecular Theory. [Internet] [Doctoral dissertation]. Rice University; 2015. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/1911/87693.

Council of Science Editors:

Ahmed W. A Systematic Study of Short and Long Range Interactions in Associating Fluids Using Molecular Theory. [Doctoral Dissertation]. Rice University; 2015. Available from: http://hdl.handle.net/1911/87693

10. Takeda, Michael. Evidence for methane hydrate stability zones during Pleistocene glaciation at the Bruce Nuclear Site.

Degree: 2013, University of Waterloo

URL: http://hdl.handle.net/10012/7552

► A gas hydrate refers to the state in which hydrogen-bonded water molecules form a rigid lattice structure of so-called "cages", wherein "guest" molecules of natural… (more)

▼ A gas hydrate refers to the state in which hydrogen-bonded water molecules form a rigid lattice structure of so-called "cages", wherein "guest" molecules of natural gas are entrapped. Not unlike ice, gas hydrates are prone to form at low temperatures and high pressures; however, their crystalline structure allows them to remain stable at temperatures and pressures under which the phase limits of ice would otherwise be exceeded. To date, a number of instances of gas hydrates forming in the subsurface of Arctic climates below layers of permafrost have been identified, however the challenge of identifying past occurrences of methane hydrates during episodes of global cooling and glacial advance remains relatively unmet. During these periods of glacial/permafrost cover, the presence of hydrates could have a significant impact on the groundwater flow system due to the significant reduction of the porosity and permeability of hydrate saturated sediments. The purpose of this study is to investigate whether there is evidence to suggest that methane hydrates could have formed in the sedimentary units of the Michigan Basin at the Bruce nuclear site near Kincardine, Ontario, particularly when subjected to the impacts of glacial ice sheet loading. This study aims to provide insight into whether the potential impact of gas hydrates should be considered in the design of the proposed deep-geologic repository (DGR) for low- and intermediate-level nuclear waste. This study presents a framework employing regional-scale numerical modelling to estimate the evolution of temperature, pressure and salinity profiles across the study area, combined with thermodynamic predictive modelling to identify potential paleo-methane hydrate stability zones in the subsurface at the Bruce nuclear site. This study represents the first step to ultimately assess the extent of paleo-methane hydrates and their impact on subsurface conditions at the site. Transient subsurface conditions at the Bruce nuclear site were modelled over a period of 120,000 years (120 ka), encompassing episodes of glacial advance and retreat during the Pleistocene epoch. The spatial and transient outputs from numerical modelling of the study area were then used as inputs to thermodynamic predictive modelling of methane hydrate stability. The results of this study show that, based upon the subsurface temperature, pressure and salinity histories determined using a three-dimensional regional-scale numerical modelling approach, paleo-conditions at the Bruce nuclear site become conducive with methane hydrate stability during the study period. Two separate episodes of methane hydrate stability were identified - lasting from 62.5 to 56 thousand years before present (kaBP) and from 23 to 13.5 kaBP, respectively - which were found to correspond to periods of glacial advance across the study area. The vertical extent of the estimated hydrate stability zones varied across the site, however it generally followed the limits of the Upper Silurian units, penetrating to deeper elevations…

Subjects/Keywords: gas hydrates

…26 2.12 Map of known and inferred locations of Gas Hydrates in Ocean Sediments and Arctic… …Not unlike ice, gas hydrates are prone to form at low temperatures and high pressures… …Based on their physical properties, gas hydrates can be regarded as dense nonflowing solids… …formation of gas hydrates in oil and gas pipelines and their negative implications on gas… …conveyance, to the natural occurrence of gas hydrates in subsurface terrestrial environments and…

10 more images…

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APA (6^th Edition):

Takeda, M. (2013). Evidence for methane hydrate stability zones during Pleistocene glaciation at the Bruce Nuclear Site. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/7552

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Takeda, Michael. “Evidence for methane hydrate stability zones during Pleistocene glaciation at the Bruce Nuclear Site.” 2013. Thesis, University of Waterloo. Accessed January 27, 2021. http://hdl.handle.net/10012/7552.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Takeda, Michael. “Evidence for methane hydrate stability zones during Pleistocene glaciation at the Bruce Nuclear Site.” 2013. Web. 27 Jan 2021.

Vancouver:

Takeda M. Evidence for methane hydrate stability zones during Pleistocene glaciation at the Bruce Nuclear Site. [Internet] [Thesis]. University of Waterloo; 2013. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/10012/7552.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Takeda M. Evidence for methane hydrate stability zones during Pleistocene glaciation at the Bruce Nuclear Site. [Thesis]. University of Waterloo; 2013. Available from: http://hdl.handle.net/10012/7552

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University

11. Gai, Xuerui. Geomechanical Modeling of Gas Hydrate Bearing Sediments and Other Complex Soils.

Degree: PhD, Civil Engineering, 2018, Texas A&M University

URL: http://hdl.handle.net/1969.1/188900

► The research presented in this dissertation is aimed at advancing the current understanding of the mechanical behavior of three distinct complex soil systems, as follows:… (more)

▼ The research presented in this dissertation is aimed at advancing the current understanding of the mechanical behavior of three distinct complex soil systems, as follows: gas hydrate bearing sediment, partially saturated clay silt and microbially induced calcite precipitation treated sands. Particular emphasis is placed on the mechanical constitutive modeling of these different soil systems. Gas hydrate bearing sediments (GHBS) are considered a potential future energy resource. The existence of the ice-like hydrates in the pore space and the associated phase change during hydrate dissociation make the modeling of GHBS very challenging. This thesis presents two novel constitutive models for GHBS that incorporate a number of improvements that allow simulating features of sediments behavior that were not captured by previous approaches. First, a simpler model was developed based on the critical state soil mechanics theory for strain hardening materials which was enhanced and validated with experimental tests involving shearing at constant hydrate saturation. This basic model was then upgraded using strain-partition concepts with the aim to achieve a better description of GHBS behavior. This model allows tracking the evolution of the mechanical contribution from the sediment and hydrate during shearing and dissociation. This is a novel aspect that was not considered in previous constitutive models and that greatly assists to gain a better understanding about the geomechanical response of this complex multiphase material. The progresses and developments made in the constitutive modeling of GHBS were adapted and extended to model other two geomaterials of great interest nowadays, as follows: unsaturated soils and treated soils by microbially induced calcite precipitation (MICP). The study of unsaturated soils is very relevant as they are often encountered in engineering applications. Furthermore, the mechanical behavior of partially saturated soils can be very different compared to that of fully saturated ones. The most popular framework to study the behavior of unsaturated soils is the so-called Barcelona Basic Model (BBM). This is an excellent model able to capture the main features of unsaturated soils, however it has some limitations to properly model materials exhibiting dilatancy during shearing. This model has been enhanced in this thesis. A critical comparison between the performances of these two models is carried out. It is observed that the enhanced model is able to satisfactorily capture the complex behavior observed in the lab and improve the response of the BBM for this type of soils. Finally, the focus is on the study of MICP treated soils. Microbially induced calcite precipitation (MICP) is a promising soil improvement technique for improving the performance of soft/loose soils. Sand is often the selected host soil in the lab to investigate this type of treatment. The mechanical behavior of MICP treated sand is carefully reviewed and an elastoplastic constitutive model is proposed for first time. The… Advisors/Committee Members: Sanchez, Marcelo (advisor), Aubeny, Charles (committee member), Lytton, Robert (committee member), Akkutlu, I. Yucel (committee member).

Subjects/Keywords: gas hydrates; bearing sediment; constitutive modeling

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gai, X. (2018). Geomechanical Modeling of Gas Hydrate Bearing Sediments and Other Complex Soils. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/188900

Chicago Manual of Style (16^th Edition):

Gai, Xuerui. “Geomechanical Modeling of Gas Hydrate Bearing Sediments and Other Complex Soils.” 2018. Doctoral Dissertation, Texas A&M University. Accessed January 27, 2021. http://hdl.handle.net/1969.1/188900.

MLA Handbook (7^th Edition):

Gai, Xuerui. “Geomechanical Modeling of Gas Hydrate Bearing Sediments and Other Complex Soils.” 2018. Web. 27 Jan 2021.

Vancouver:

Gai X. Geomechanical Modeling of Gas Hydrate Bearing Sediments and Other Complex Soils. [Internet] [Doctoral dissertation]. Texas A&M University; 2018. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/1969.1/188900.

Council of Science Editors:

Gai X. Geomechanical Modeling of Gas Hydrate Bearing Sediments and Other Complex Soils. [Doctoral Dissertation]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/188900

Colorado School of Mines

12. Webb, Eric B. Rheology of methane hydrate slurries formed from water-in-oil emulsions.

Degree: PhD, Chemical and Biological Engineering, 2014, Colorado School of Mines

URL: http://hdl.handle.net/11124/362

► Solid structures known as natural gas hydrates can form in subsea pipelines, hindering and sometimes blocking flow completely. A knowledge of the flow properties of… (more)

▼ Solid structures known as natural gas hydrates can form in subsea pipelines, hindering and sometimes blocking flow completely. A knowledge of the flow properties of hydrate containing slurries could help the oil industry better predict and prevent hydrate formation. In particular, the rheology (e.g., viscosity, yield stress) of hydrate slurries is not well understood. On a more scientific level, the transient rheological properties of an emulsion converting to a suspension has not been studied extensively. A high pressure rheometer apparatus was developed to study hydrate formation from water-in-oil emulsions. This study conducted investigations on three different emulsions from which hydrates were formed: water-in-West African crude oil (a fluid found in subsea pipelines), water-in-dodecane with AOT surfactant (a model emulsion with low viscosity), and water-in-70T mineral oil with span 80 and AOT surfactants (a model emulsion with high viscosity). Each of these emulsions provides a unique way to observe hydrate rheology. In every emulsion, viscosity increased on the order of minutes upon hydrate formation. Hydrate formation from water-in-oil emulsions increased viscosity, increased shear-thinning behavior, and introduced a yield stress to the original emulsion. The transient viscosity profile as hydrate form and grow were influenced by many factors including conversion of liquid water drops to solid particles, aggregation of hydrate particles, methane depletion and diffusion, and capillary bridging. In the mineral oil-based system, methane saturated emulsion viscosity was about an order of magnitude larger than methane saturated mineral oil viscosity. The maximum viscosity observed during hydrate formation was on the order of a 10-fold increase in viscosity. So, introduction of water to oil in a pipeline followed by hydrate formation may cause a 100-fold increase in viscosity. Fractional conversion of water to hydrate was calculated from pressure measurements. Hydrate slurry viscosity reached a maximum at less than 100% conversion of water to hydrate; so, viscosity of this part-suspension-part-emulsion was higher than suspension or emulsion viscosity. In the dodecane and mineral oil-based emulsions, if significant unconverted water remained after the initial formation event, viscosity increased for a time as additional methane dissolved and converted some remaining water to hydrate. In general, decreased driving force (e.g., temperature) for hydrate formation resulted in increased rheological properties (transient viscosity, yield stress, steady state viscosity). Advisors/Committee Members: Liberatore, Matthew W. (advisor), Koh, Carolyn A. (Carolyn Ann) (committee member), Wu, Ning (committee member), Neeves, Keith B. (committee member), Tonmukayakul, Peng (committee member), Yin, Xiaolong (committee member), Sum, Amadeu K. (committee member).

Subjects/Keywords: hydrates; colloids; crude oil; emulsion; flow assurance; rheology; Rheology; Natural gas – Hydrates; Hydrates; Emulsions – Testing; Methane; Slurry; Rheometers

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Webb, E. B. (2014). Rheology of methane hydrate slurries formed from water-in-oil emulsions. (Doctoral Dissertation). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/362

Chicago Manual of Style (16^th Edition):

Webb, Eric B. “Rheology of methane hydrate slurries formed from water-in-oil emulsions.” 2014. Doctoral Dissertation, Colorado School of Mines. Accessed January 27, 2021. http://hdl.handle.net/11124/362.

MLA Handbook (7^th Edition):

Webb, Eric B. “Rheology of methane hydrate slurries formed from water-in-oil emulsions.” 2014. Web. 27 Jan 2021.

Vancouver:

Webb EB. Rheology of methane hydrate slurries formed from water-in-oil emulsions. [Internet] [Doctoral dissertation]. Colorado School of Mines; 2014. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/11124/362.

Council of Science Editors:

Webb EB. Rheology of methane hydrate slurries formed from water-in-oil emulsions. [Doctoral Dissertation]. Colorado School of Mines; 2014. Available from: http://hdl.handle.net/11124/362

University of KwaZulu-Natal

13. Ghiasi, Mohammad Mahdi. Development of Coordinated Methodologies for Modeling CO2-Containing Systems in Petroleum Industry.

Degree: 2018, University of KwaZulu-Natal

URL: https://researchspace.ukzn.ac.za/handle/10413/17484

► Clathrate hydrates formation in natural gas processing facilities or transportation pipelines may lead to process and/or safety hazards. On the other hand, a number of… (more)

▼ Clathrate hydrates formation in natural gas processing facilities or transportation pipelines may lead to process and/or safety hazards. On the other hand, a number of applications are suggested on the basis of promoting the gas hydrate formation. Some researchers have investigated separation and purification processes through gas hydrate crystallization technology. Some works report that the hydrate formation is applicable to the gas transportation and storage. Gas hydrate concept is also studied as a potential method for CO2 capture and/or sequestration. Water desalination/sweetening, and refrigeration and air conditioning systems are other proposed uses of hydrates phenomenon. In the realm of food processing and engineering, several studies have been done investigating the application of gas hydrate technology as an alternative to the conventional processes. Accurate knowledge of phase equilibria of clathrate hydrates is crucial for preventing or utilizing the hydrates. It is believed that energy production or extraction from different fossil fuels is responsible for considerable emissions of CO2, as an important greenhouse gas, into the atmosphere. Furthermore, CO2 removal from the streams of natural gas is important for enhancing the gaseous streams’ heating value. Employment of solvent-based processes and technologies for removing the CO2 is a widely employed approach in practical applications. Amine-based or pure amine solutions are the most common choice to remove the produced CO2 in numerous carbon capture systems. Further to the above, ionic liquids (ILs) are capable to be utilized to capture CO2 from industrial streams. Other potential solvent are sodium piperazine (PZ) and glycinate (SG) solutions. Equilibrium absorption of carbon dioxide in the aqueous phase is a key parameter in any solvent-based CO2 capture process designing. The captured CO2, then, can be injected into the hydrocarbon reservoirs. In addition to the fact that injection of CO2 into potential sources is one of the most reliable methodologies for enhanced hydrocarbon recovery, utilizing this process in conjunction with the CO2 capture systems mitigates the greenhouse effects of CO2. One of the most significant variables determining the success of CO2 injection is known to be the minimum miscibility pressure (MMP) of CO2-reservoir oil. This research study concerns implementation of computer-based methodologies called artificial neural networks (ANNs), classification and regression trees (CARTs)/AdaBoost-CART, adaptive neuro-fuzzy inference systems (ANFISs) and least squares support vector machines (LSSVMs) for modeling: (a) phase equilibria of clathrate hydrates in: 1- pure water, 2- aqueous solutions of salts and/or alcohols, and 3- ILs, (b) phase equilibria (equilibrium) of hydrates of methane in ILs; (c) equilibrium absorption of CO2 in amine-based solutions, ILs, PZ solutions, and SG solutions; and (d) MMP of CO2-reservoir oil. To this end, related experimental data have been gathered from the literature. Performing error analysis,… Advisors/Committee Members: Mohammadi, Amir Hossein. (advisor), Ramjugernath, Deresh. (advisor).

Subjects/Keywords: Petroleum industry.; Clathrate hydrates.; Hydrates formation.; Gas hydrate technology.; Carbon dioxide.; Machine learning.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ghiasi, M. M. (2018). Development of Coordinated Methodologies for Modeling CO2-Containing Systems in Petroleum Industry. (Thesis). University of KwaZulu-Natal. Retrieved from https://researchspace.ukzn.ac.za/handle/10413/17484

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ghiasi, Mohammad Mahdi. “Development of Coordinated Methodologies for Modeling CO2-Containing Systems in Petroleum Industry.” 2018. Thesis, University of KwaZulu-Natal. Accessed January 27, 2021. https://researchspace.ukzn.ac.za/handle/10413/17484.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ghiasi, Mohammad Mahdi. “Development of Coordinated Methodologies for Modeling CO2-Containing Systems in Petroleum Industry.” 2018. Web. 27 Jan 2021.

Vancouver:

Ghiasi MM. Development of Coordinated Methodologies for Modeling CO2-Containing Systems in Petroleum Industry. [Internet] [Thesis]. University of KwaZulu-Natal; 2018. [cited 2021 Jan 27]. Available from: https://researchspace.ukzn.ac.za/handle/10413/17484.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ghiasi MM. Development of Coordinated Methodologies for Modeling CO2-Containing Systems in Petroleum Industry. [Thesis]. University of KwaZulu-Natal; 2018. Available from: https://researchspace.ukzn.ac.za/handle/10413/17484

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Curtin University of Technology

14. Rojas González, Yenny V. Tetrahydrofuran and natural gas hydrates formation in the presence of various inhibitors .

Degree: 2011, Curtin University of Technology

URL: http://hdl.handle.net/20.500.11937/2332

► The aim of this thesis is to investigate the formation process of tetrahydrofuran (THF) hydrates and natural gas hydrates, and the effect of kinetic hydrate… (more)

▼ The aim of this thesis is to investigate the formation process of tetrahydrofuran (THF) hydrates and natural gas hydrates, and the effect of kinetic hydrate inhibitors (KHIs) on the formation and growth of these hydrates. Kinetic experiments were conducted in pressure cells in the presence of, or without, KHIs. Interfacial and electrokinetic techniques, including surface tension, Langmuir monolayers and zeta potential, were used to study the adsorption preferences of the inhibitors in two different interfaces, air–liquid and hydrate–liquid. For comparison purposes, selected thermodynamic hydrate inhibitors (THIs) and antiagglomerators (AAs) were investigated in some of the experiments. Sodium chloride was used in experiments where suitable.Four well known KHI polymers, including a terpolymer of N-vinylpyrrolidone, Nvinylcaprolactam and dimethylamino-ethylmethacrylate (Gaffix VC713), poly(Nvinylcaprolactam) (Luvicap EG), and poly(N-vinylpyrrolidone) (PVP40, Mn=40k and PVP360, Mn=360k), were selected for the investigation. A copolymer containing both poly(ethylene oxide) and vinylcaprolactam segments (PEO-VCap) that was developed in the Polymer Research lab in Curtin University, was also investigated. Other chemicals, including methanol (MeOH) and monoethylene glycol (MEG) were used as THIs. Sodium dodecyl sulphate (SDS) was used as an AA.During the THF hydrates kinetic studies, several experimental parameters that are associated with the nucleation and crystal growth process were investigated. The onset of THF hydrates formation, the maximum temperature spike, the magnitude of the temperature rise associated with the hydrate formation, the rate of hydrate formation, and the temperature at the end-point of the hydrate formation, were reported to compare inhibition efficiency. Subcooling was used as the driving force for hydrates formation. The experimental results show that the kinetics of the THF hydrate is affected by the physical chemical environment, which includes the concentration and types of additives used for the inhibition of the hydrates. In comparison to the system containing no inhibitor, there was an increase in subcooling and a reduced onset temperature of hydrates formation when various inhibitors were used.Surface tension studies have demonstrated that the adsorption of KHIs molecules at the air–liquid interface is directly related to its effectiveness inhibiting hydrates. The differences in the fundamental properties of the polymer molecules, such as molecular weight and flexibility of the polymer chain, have an impact on the different adsorption behaviours at the air–liquid interface for all of them. The inhibition efficiency of KHIs was enhanced in the presence of NaCl 3.5 wt% for all the inhibitors, and seemed to be associated to maximum packing of polymer molecules in the monolayer and low surface tension values. The zeta potential results, measured at the THF hydrate–liquid interface, have shown some correspondence with the surface tension results at the air liquid–interface. The compound, with…

Subjects/Keywords: tetrahydrofuran (THF) hydrates; natural gas hydrates formation; formation process; kinetic hydrate inhibitors (KHIs)

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APA (6^th Edition):

Rojas González, Y. V. (2011). Tetrahydrofuran and natural gas hydrates formation in the presence of various inhibitors . (Thesis). Curtin University of Technology. Retrieved from http://hdl.handle.net/20.500.11937/2332

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Rojas González, Yenny V. “Tetrahydrofuran and natural gas hydrates formation in the presence of various inhibitors .” 2011. Thesis, Curtin University of Technology. Accessed January 27, 2021. http://hdl.handle.net/20.500.11937/2332.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Rojas González, Yenny V. “Tetrahydrofuran and natural gas hydrates formation in the presence of various inhibitors .” 2011. Web. 27 Jan 2021.

Vancouver:

Rojas González YV. Tetrahydrofuran and natural gas hydrates formation in the presence of various inhibitors . [Internet] [Thesis]. Curtin University of Technology; 2011. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/20.500.11937/2332.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Rojas González YV. Tetrahydrofuran and natural gas hydrates formation in the presence of various inhibitors . [Thesis]. Curtin University of Technology; 2011. Available from: http://hdl.handle.net/20.500.11937/2332

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Colorado School of Mines

15. Khan, Muhammad N. Phase equilibria modeling of inhibited gas hydrate systems including salts: applications in flow assurance, seawater desalination and gas separation.

Degree: PhD, Chemical and Biological Engineering, 2016, Colorado School of Mines

URL: http://hdl.handle.net/11124/170013

► Accurate hydrate phase equilibria and vapor-liquid equilibria predictions are critical to the safe and economic design of flow assurance, gas processing, and seawater desalination technologies.… (more)

▼ Accurate hydrate phase equilibria and vapor-liquid equilibria predictions are critical to the safe and economic design of flow assurance, gas processing, and seawater desalination technologies. Inaccurate predictions of vapor-liquid equilibria can also lead to erroneous hydrate phase equilibria predictions. Hydrate phase equilibria predictions typically use the classical van der Waals and Platteeuw (vdWP) model based on statistical thermodynamics, with some modifications (e.g. CSMGem, with Gibbs Energy Minimization). In this thesis work, the vdWP model with Gibbs Energy Minimization algorithm was developed in Matlab. The developed algorithm was evaluated by first investigating the effect of hydrogen (H2) concentration on the phase equilibria of sH hydrate (i.e. H2O+CH4+H2+methylcyclohexane (MCH) quaternary systems). The predictions were shown to be in close agreement with experimental phase equilibria measurements. Cage occupancies of methane and hydrogen in sH hydrate were predicted to increase with increasing pressure, and the extent of occupation was found to be dependent on the methane: hydrogen ratio in the feed gas. Current hydrate phase equilibria predictions (using different models, e.g. CSMGem, Multiflash and PVTsim) for inhibited systems in subsea pipelines (with salts, e.g. NaCl, KCl, CaCl2, also thermodynamic hydrate inhibitors (THIs), e.g. methanol, monoethylene glycol) exhibit large errors. The unavailability of phase equilibria data and absence of an association equation of state in CSMGem leads to problems in predicting the phase equilibria of associating fluids and inhibited systems. Therefore, the current CSMGem model is not reliable for predicting these inhibited systems. Such thermodynamic calculations are critical to flow assurance and desalination process design. To overcome these limitations this work revisited the fluid model and a new fluid model is proposed for phase equilibria predictions; an association equation of state has been developed and applied to predict fluid phase properties for a wide range of hydrocarbons (low to high MWt), polar components and electrolytes (salts). Five parameters of the association equation of state were determined for the associating components by simultaneous minimization of absolute errors in saturated liquid densities and vapor pressures, with comparisons to experimental data. In order to predict the phase equilibria of gas hydrates without inhibitors, the proposed association equation of state needs to be tuned with vapor-liquid equilibria. In this thesis work experimental hydrate phase equilibria and vapor-liquid equilibria data (over a range of temperature, pressure and composition) were collated and utilized to tune the fluid and hydrate models. Binary interaction parameters were optimized for a range of hydrate formers, including methane, ethane, nitrogen and hydrogen in combination with all other available hydrocarbons. Different equations of state were also used to predict the vapor-liquid equilibria for mixtures of methane, ethane, nitrogen and… Advisors/Committee Members: Koh, Carolyn A. (Carolyn Ann) (advisor), Peters, Cor J. (advisor), Zerpa, Luis E. (committee member), Way, J. Douglas (committee member), Krebs, Melissa D. (committee member).

Subjects/Keywords: desalination; electrolyte; gas hydrates; gas separation; MSA; phase equilibria

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APA (6^th Edition):

Khan, M. N. (2016). Phase equilibria modeling of inhibited gas hydrate systems including salts: applications in flow assurance, seawater desalination and gas separation. (Doctoral Dissertation). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/170013

Chicago Manual of Style (16^th Edition):

Khan, Muhammad N. “Phase equilibria modeling of inhibited gas hydrate systems including salts: applications in flow assurance, seawater desalination and gas separation.” 2016. Doctoral Dissertation, Colorado School of Mines. Accessed January 27, 2021. http://hdl.handle.net/11124/170013.

MLA Handbook (7^th Edition):

Khan, Muhammad N. “Phase equilibria modeling of inhibited gas hydrate systems including salts: applications in flow assurance, seawater desalination and gas separation.” 2016. Web. 27 Jan 2021.

Vancouver:

Khan MN. Phase equilibria modeling of inhibited gas hydrate systems including salts: applications in flow assurance, seawater desalination and gas separation. [Internet] [Doctoral dissertation]. Colorado School of Mines; 2016. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/11124/170013.

Council of Science Editors:

Khan MN. Phase equilibria modeling of inhibited gas hydrate systems including salts: applications in flow assurance, seawater desalination and gas separation. [Doctoral Dissertation]. Colorado School of Mines; 2016. Available from: http://hdl.handle.net/11124/170013

Curtin University of Technology

16. Battah, Sam. Natural gas hydrate production .

Degree: 2002, Curtin University of Technology

URL: http://hdl.handle.net/20.500.11937/1221

► The concept which led to the establishment of the research in natural gas hydrate production, was born by Dr. Robert Amin (currently Professor of Petroleum… (more)

▼ The concept which led to the establishment of the research in natural gas hydrate production, was born by Dr. Robert Amin (currently Professor of Petroleum Engineering at Curtin University and Chair of the Woodside Research Foundation) and Alan Jackson of Woodside Energy. The intended research in this field is to establish the viability of utilizing a synthesised natural gas hydrate as a means to allow a cheaper form of transportation of natural gas from the wellhead to the customer in direct competition with liquefied natural gas (LNG). Natural gas exists in ice-like formations called hydrates found on or under sea-beds and under permafrost. Hydrates trap methane molecules inside a cage of frozen water, where the amount of hydrates trapped is dependent on surrounding formation pressure. The amount of natural gas trapped in hydrates is largely unknown, but it is very large. A number of scientists believe that hydrates contain more than twice as much energy as all the world's coal, oil, and natural gas combined, hence making it a viable option of fuel in the 21st century, in a world constantly seeking cleaner sources of energy. The feasibility of production of natural gas hydrates on offshore installations and onshore facilities makes this development a viable option. As such this technology requires detailed research and development in a laboratory environment coupled with a pilot plant construction for commercial operation. Current estimates for onshore based facilities for the production of hydrates show a cost reduction of approximately 25% compared with LNG plants of the same energy capacity.There are two major issues which require detailed research and development in order to progress this technology. First is the enhancement of the hydrates production by the use of other additives, and second, the continuous production at near atmospheric pressures. Other research related to transport methodology and re-gasification will be essential for the overall success of this technology, however, this work is outside the scope of this research.

Subjects/Keywords: hydrates; natural gas; gas formation

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APA (6^th Edition):

Battah, S. (2002). Natural gas hydrate production . (Thesis). Curtin University of Technology. Retrieved from http://hdl.handle.net/20.500.11937/1221

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Battah, Sam. “Natural gas hydrate production .” 2002. Thesis, Curtin University of Technology. Accessed January 27, 2021. http://hdl.handle.net/20.500.11937/1221.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Battah, Sam. “Natural gas hydrate production .” 2002. Web. 27 Jan 2021.

Vancouver:

Battah S. Natural gas hydrate production . [Internet] [Thesis]. Curtin University of Technology; 2002. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/20.500.11937/1221.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Battah S. Natural gas hydrate production . [Thesis]. Curtin University of Technology; 2002. Available from: http://hdl.handle.net/20.500.11937/1221

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Colorado School of Mines

17. Ward, Zachary Thomas. Phase equilibria of gas hydrates containing hydrogen sulfide and carbon dioxide.

Degree: PhD, Chemical and Biological Engineering, 2015, Colorado School of Mines

URL: http://hdl.handle.net/11124/20280

► Production of gas fields containing carbon dioxide and hydrogen sulfide is becoming more prevalent in the global oil and gas industry. As conventional wells are… (more)

▼ Production of gas fields containing carbon dioxide and hydrogen sulfide is becoming more prevalent in the global oil and gas industry. As conventional wells are depleted and the economics of unconventional gas production become favorable, the industry has responded by producing gas fields containing acid gas (CO2 and/or H2S). CO2 and H2S are the cause of a wide range of flow assurance issues that the industry are currently experiencing, including their strong tendency to form gas hydrate crystals that can plug flowlines. However, due to the challenging experimental conditions (long time scale, toxicity, high pressure, specialty cell materials required due to corrosion in these systems) for phase equilibria measurements of acid gas systems, there is a paucity of available data in the literature. The purpose of this thesis is to provide advanced understanding and new data critical to the development and validation of model predictions of gas hydrate phase equilibria for systems containing CO2 and H2S. New hydrate phase equilibria measurements were performed for pure H2S hydrates, binary CH4 + H2S hydrates, ternary CH4 + C3H8 + H2S hydrates, and ternary CH4 + C3H8 + CO2 hydrates using the isochoric pressure search method in stainless steel and Hastelloy C autoclaves, as well as using a step-scan technique in a high pressure differential scanning calorimeter. These measurements were compared with literature and commercial software used in academia and industry for predicting hydrate formation temperatures and pressures. These new data were then incorporated into the non-ideal hydrate solid solution Gibbs energy minimization multi-phase equilibria program, CSMGem, to better predict hydrate formation for hydrates containing CO2 and H2S. The CSM Gibbs Energy Minimization model is based on a statistical thermodynamics model for predicting the hydrate phase fugacity. Two fitted parameters, the soft-core radius, sigma, and the potential well depth, epsilon are key in this thermodynamic model. These parameters, when optimized to the new experimental data, showed significant improvement in the model to predict hydrate phase equilibria for systems containing mixtures of light hydrocarbons and H2S. To accomplish this parameter optimization, a new interface for CSMGem was developed and written, and the Fortran files that provide the core of the program were updated to operate with modern development software. This new interface provides an important new platform for future expansion and revision of CSMGem, facilitating a better understanding of hydrate thermodynamics and model improvements in future work. New measurements for a CH4 + C3H8 + CO2 hydrate were also performed and compared with the literature. However, inconsistencies were found between the data collected in this work and the sparce data reported in the literature. Metastability, when not considered carefully, can cause significant errors in hydrate phase equilibria measurements. An analysis was performed on all measurements performed in this work to determine the… Advisors/Committee Members: Koh, Carolyn A. (Carolyn Ann) (advisor), Wu, David T. (committee member), Wu, Ning (committee member), Yin, Xiaolong (committee member), Carroll, John J. (committee member), Thomas, Sally A. (committee member).

Subjects/Keywords: carbon dioxide; hydrogen sulfide; acid gas; thermodynamics; gas hydrates

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APA (6^th Edition):

Ward, Z. T. (2015). Phase equilibria of gas hydrates containing hydrogen sulfide and carbon dioxide. (Doctoral Dissertation). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/20280

Chicago Manual of Style (16^th Edition):

Ward, Zachary Thomas. “Phase equilibria of gas hydrates containing hydrogen sulfide and carbon dioxide.” 2015. Doctoral Dissertation, Colorado School of Mines. Accessed January 27, 2021. http://hdl.handle.net/11124/20280.

MLA Handbook (7^th Edition):

Ward, Zachary Thomas. “Phase equilibria of gas hydrates containing hydrogen sulfide and carbon dioxide.” 2015. Web. 27 Jan 2021.

Vancouver:

Ward ZT. Phase equilibria of gas hydrates containing hydrogen sulfide and carbon dioxide. [Internet] [Doctoral dissertation]. Colorado School of Mines; 2015. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/11124/20280.

Council of Science Editors:

Ward ZT. Phase equilibria of gas hydrates containing hydrogen sulfide and carbon dioxide. [Doctoral Dissertation]. Colorado School of Mines; 2015. Available from: http://hdl.handle.net/11124/20280

Penn State University

18. Nago, Annick Blanche Christelle Logbochy. Application of numerical, experimental and life cycle assessment methods to the investigation of natural gas production from methane hydrate deposits using carbon dioxide clathrate sequestration.

Degree: 2013, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/16432

► Natural gas hydrates, commonly called methane (CH4) hydrates, are ice-like materials belonging to the family of clathrates that form at low temperature and high pressure.… (more)

▼ Natural gas hydrates, commonly called methane (CH4) hydrates, are ice-like materials belonging to the family of clathrates that form at low temperature and high pressure. They can be found in permafrost and oceanic environments. The amount of natural gas trapped into worldwide hydrate deposits has been estimated at 18000 trillion m3 of methane [1] and it surpasses the world natural gas proven reserves (180 trillion m3 [2]) by two orders of magnitude. Fossil fuel based energy is still a major source of carbon dioxide (CO2) emissions. Hence, it contributes greatly to the issues of global warming and climate change. Geological sequestration of carbon dioxide appears as the safest and most stable way to reduce such emissions for it involves CO2 entrapment into hydrocarbon reservoirs and aquifers. Indeed, CO2 can also be sequestered as hydrates while assisting in the dissociation of in-situ methane hydrates. This approach could help mitigate the emissions of CO2 in the atmosphere and improve the economics of carbon dioxide sequestration and natural gas production from hydrate deposits. The proposed research focused on investigating the feasibility of the CO2-CH4 exchange in hydrates as a gas hydrate mining method through experimental studies and numerical modeling of the exchange, as well as the application of a life-cycle assessment (LCA) approach to the evaluation of CO2 emissions resulting from the use of the replacement technique. Under the limitations of our numerical model and experiments, we were able to establish the influence of initial reservoir temperature and pressure on the performance of the exchange. We also noticed the influence of the presence of excess water during the exchange. These observations have been confirmed in the relevant literature. The application of the life cycle assessment method to the process of gas production from a hypothetical hydrate reservoir allowed us to highlight conditions where the use of the exchange technique could lead to emission-neutral gas extraction from methane hydrate deposits. Advisors/Committee Members: Antonio Nieto, Dissertation Advisor/Co-Advisor, Antonio Nieto, Committee Chair/Co-Chair, Zuleima T Karpyn, Committee Member, Dr Luis Ayala, Committee Member, Jeffrey Brownson, Committee Member, John Richard Hellmann Jr., Committee Member.

Subjects/Keywords: Natural gas hydrates; CO2-CH4 exchange in hydrates; numerical modeling; life cycle assessment; CO2 emissions; natural gas production

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APA (6^th Edition):

Nago, A. B. C. L. (2013). Application of numerical, experimental and life cycle assessment methods to the investigation of natural gas production from methane hydrate deposits using carbon dioxide clathrate sequestration. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/16432

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Nago, Annick Blanche Christelle Logbochy. “Application of numerical, experimental and life cycle assessment methods to the investigation of natural gas production from methane hydrate deposits using carbon dioxide clathrate sequestration.” 2013. Thesis, Penn State University. Accessed January 27, 2021. https://submit-etda.libraries.psu.edu/catalog/16432.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Nago, Annick Blanche Christelle Logbochy. “Application of numerical, experimental and life cycle assessment methods to the investigation of natural gas production from methane hydrate deposits using carbon dioxide clathrate sequestration.” 2013. Web. 27 Jan 2021.

Vancouver:

Nago ABCL. Application of numerical, experimental and life cycle assessment methods to the investigation of natural gas production from methane hydrate deposits using carbon dioxide clathrate sequestration. [Internet] [Thesis]. Penn State University; 2013. [cited 2021 Jan 27]. Available from: https://submit-etda.libraries.psu.edu/catalog/16432.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Nago ABCL. Application of numerical, experimental and life cycle assessment methods to the investigation of natural gas production from methane hydrate deposits using carbon dioxide clathrate sequestration. [Thesis]. Penn State University; 2013. Available from: https://submit-etda.libraries.psu.edu/catalog/16432

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Colorado School of Mines

19. Zerpa, Luis E. Practical model to predict gas hydrate formation, dissociation and transportability in oil and gas flowlines, A.

Degree: PhD, Petroleum Engineering, 2013, Colorado School of Mines

URL: http://hdl.handle.net/11124/78776

► The oil and gas industry is facing very challenging production issues with offshore explorations in deeper and colder waters. Longer subsea tiebacks will be required… (more)

▼ The oil and gas industry is facing very challenging production issues with offshore explorations in deeper and colder waters. Longer subsea tiebacks will be required to transport hydrocarbon fluids from the wellhead to production and processing platforms. The formation of solid deposits, such as gas hydrates, waxes, asphaltenes and scale, may plug the flowlines, preventing production and generating a safety hazard. The flow assurance of the produced hydrocarbon stream is a technical discipline that focuses on the design of facilities and procedures for the uninterrupted transport of reservoir fluids from the reservoir to the point of sale. The rapid formation of gas hydrates, which is promoted by typical high pressure/low temperature operation conditions in deep subsea facilities, is considered one of the most challenging flow assurance problems. A transient gas hydrate model, that predicts when and where hydrate plugs will form in flowlines, will have significant utility for the flow assurance engineers in the oil and gas industry. The Colorado School of Mines Hydrate Kinetics model (CSMHyK) was specially designed to predict hydrate formation in oil-dominated systems. The objective of this research work is to develop a comprehensive hydrate model, extending and improving the CSMHyK model for the prediction of hydrate formation and transportability in oil, water and gas-dominated systems. The mechanisms of hydrate formation and transportability in pipelines is studied through the analysis of experimental data obtained at the Center for Hydrate Research laboratory of the Colorado School of Mines and two large scale flow loops (ExxonMobil and Tulsa University flow loops). A set of conceptual pictures is developed to explain the physical phenomena of gas hydrate formation in flowlines. The mathematical models developed in this work represent a significant advancement for the prediction of hydrate plugging risk in the pipelines of oil and gas transport facilities, and can be used as a tool to design flow assurance strategies. These models improve our capability to predict hydrate formation, by considering dynamic aggregation phenomena in oil-dominated systems, flow regime transition in high water cut systems, and hydrate film growth in gas-dominated systems. Advisors/Committee Members: Kazemi, Hossein (advisor), Koh, Carolyn A. (Carolyn Ann) (advisor), Batzle, Michael L. (committee member), Wu, Yu-Shu (committee member), Yin, Xiaolong (committee member), Sum, Amadeu K. (committee member).

Subjects/Keywords: gas hydrates; flow assurance; surface chemistry; multiphase flow in pipelines; modeling; Natural gas – Hydrates; Hydrates – Computer simulation; Petroleum pipelines – Fluid dynamics; Multiphase flow

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APA (6^th Edition):

Zerpa, L. E. (2013). Practical model to predict gas hydrate formation, dissociation and transportability in oil and gas flowlines, A. (Doctoral Dissertation). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/78776

Chicago Manual of Style (16^th Edition):

Zerpa, Luis E. “Practical model to predict gas hydrate formation, dissociation and transportability in oil and gas flowlines, A.” 2013. Doctoral Dissertation, Colorado School of Mines. Accessed January 27, 2021. http://hdl.handle.net/11124/78776.

MLA Handbook (7^th Edition):

Zerpa, Luis E. “Practical model to predict gas hydrate formation, dissociation and transportability in oil and gas flowlines, A.” 2013. Web. 27 Jan 2021.

Vancouver:

Zerpa LE. Practical model to predict gas hydrate formation, dissociation and transportability in oil and gas flowlines, A. [Internet] [Doctoral dissertation]. Colorado School of Mines; 2013. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/11124/78776.

Council of Science Editors:

Zerpa LE. Practical model to predict gas hydrate formation, dissociation and transportability in oil and gas flowlines, A. [Doctoral Dissertation]. Colorado School of Mines; 2013. Available from: http://hdl.handle.net/11124/78776

Rochester Institute of Technology

20. Zhang, Yali. Prediction of Gas-hydrate Equilibrium, Stability and Kinetic Nucleation in Porous Media.

Degree: PhD, Microsystems Engineering, 2020, Rochester Institute of Technology

URL: https://scholarworks.rit.edu/theses/10456

► Natural gas-hydrates are crystalline inclusion compounds with gas molecules (guest compounds) trapped within a host lattice formed by water molecules in an ice-like hydrogen-bonded… (more)

Subjects/Keywords: Equilibrium prediction; Formation probability; Gas hydrates; Kinetic nucleation

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APA (6^th Edition):

Zhang, Y. (2020). Prediction of Gas-hydrate Equilibrium, Stability and Kinetic Nucleation in Porous Media. (Doctoral Dissertation). Rochester Institute of Technology. Retrieved from https://scholarworks.rit.edu/theses/10456

Chicago Manual of Style (16^th Edition):

Zhang, Yali. “Prediction of Gas-hydrate Equilibrium, Stability and Kinetic Nucleation in Porous Media.” 2020. Doctoral Dissertation, Rochester Institute of Technology. Accessed January 27, 2021. https://scholarworks.rit.edu/theses/10456.

MLA Handbook (7^th Edition):

Zhang, Yali. “Prediction of Gas-hydrate Equilibrium, Stability and Kinetic Nucleation in Porous Media.” 2020. Web. 27 Jan 2021.

Vancouver:

Zhang Y. Prediction of Gas-hydrate Equilibrium, Stability and Kinetic Nucleation in Porous Media. [Internet] [Doctoral dissertation]. Rochester Institute of Technology; 2020. [cited 2021 Jan 27]. Available from: https://scholarworks.rit.edu/theses/10456.

Council of Science Editors:

Zhang Y. Prediction of Gas-hydrate Equilibrium, Stability and Kinetic Nucleation in Porous Media. [Doctoral Dissertation]. Rochester Institute of Technology; 2020. Available from: https://scholarworks.rit.edu/theses/10456

Texas A&M University

21. Grover, Tarun. Natural gas hydrates - issues for gas production and geomechanical stability.

Degree: PhD, Petroleum Engineering, 2008, Texas A&M University

URL: http://hdl.handle.net/1969.1/86049

► Natural gas hydrates are solid crystalline substances found in the subsurface. Since gas hydrates are stable at low temperatures and moderate pressures, gas hydrates are… (more)

Subjects/Keywords: Gas production; methane hydrates

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APA (6^th Edition):

Grover, T. (2008). Natural gas hydrates - issues for gas production and geomechanical stability. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/86049

Chicago Manual of Style (16^th Edition):

Grover, Tarun. “Natural gas hydrates - issues for gas production and geomechanical stability.” 2008. Doctoral Dissertation, Texas A&M University. Accessed January 27, 2021. http://hdl.handle.net/1969.1/86049.

MLA Handbook (7^th Edition):

Grover, Tarun. “Natural gas hydrates - issues for gas production and geomechanical stability.” 2008. Web. 27 Jan 2021.

Vancouver:

Grover T. Natural gas hydrates - issues for gas production and geomechanical stability. [Internet] [Doctoral dissertation]. Texas A&M University; 2008. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/1969.1/86049.

Council of Science Editors:

Grover T. Natural gas hydrates - issues for gas production and geomechanical stability. [Doctoral Dissertation]. Texas A&M University; 2008. Available from: http://hdl.handle.net/1969.1/86049

Texas A&M University

22. Othman, Enas Azhar. Gas Hydrate Equilibrium Measurements for Multi-Component Gas Mixtures and Effect of Ionic Liquid Inhibitors.

Degree: MS, Chemical Engineering, 2014, Texas A&M University

URL: http://hdl.handle.net/1969.1/152653

► Qatar holds the world's third-largest proven reserves of natural gas at 885 trillion cubic feet according to a recent report. Because of its desert climate,… (more)

▼ Qatar holds the world's third-largest proven reserves of natural gas at 885 trillion cubic feet according to a recent report. Because of its desert climate, gas hydrate formation may seem an unlikely event in Qatar. However, its natural gas reservoirs are located 80 km offshore, in the North Field, and the production of liquefied natural gas (LNG) depends on reliable flow from offshore wellheads to onshore processing facilities. Classical methods for inhibiting hydrate formation are used in order to prevent pipeline plugging but changing gas concentrations and operating conditions make flow assurance quite challenging in the North Field. Between 2008 and 2011, sudden temperature drops near gas pipelines caused various incidents of gas pipeline blockage by hydrates, with a loss of US$ 10 million per day due to lost production for almost 4 weeks. Such unplanned shut downs jeopardize the reliable export of LNG to end users. This work presents the recent investigation on synthetic multi-component gas mixtures whose compositions are typical of Qatari natural gases with initiatives aimed at helping producers minimize costs, optimize operations, and prevent interruption of gas flow in offshore drilling and production. In addition, it presents hydrate inhibition data from a newly commissioned micro bench top reactor, a high-pressure autoclave and a rocking cell. The conditions for hydrate formation for pure methane and carbon dioxide were also measured, for validation purposes. The measured data were compared with literature results and those of a commercial simulator, HydraFLASH®. Upon validation of the calibration data and determination of the apparatus uncertainty, results for hydrate formation equilibrium points for Qatari natural gas sample were collected and compared to HydraFLASH® predictions. Different percentages of 2-hydroxy-N,N,N-trimethylethanaminium chloride, also known as choline chloride ionic liquid, were used as hydrate inhibitor for the same gas mixture. The ionic liquid’s inhibition performance was compared to that of classical thermodynamic inhibitors (e.g. methanol). Ionic liquid inhibition showed (0.7 – 1.8) oC and (2 - 2.6) oC shift in the hydrate equilibrium curve with 1 wt. % and 5 wt. % of choline chloride respectively. While the inhibition performance of 1 wt. % and 5 wt. % of methanol, obtained using HydraFLASH® software, were 2.8 °C and 4.4 °C respectively. Advisors/Committee Members: Castier, Marcelo (advisor), Atilhan, Mert (advisor), Amani, Mahmood (committee member).

Subjects/Keywords: Natural gas hydrates; ionic liquid inhibitors; Choline chloride; HydraFLASH

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APA (6^th Edition):

Othman, E. A. (2014). Gas Hydrate Equilibrium Measurements for Multi-Component Gas Mixtures and Effect of Ionic Liquid Inhibitors. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/152653

Chicago Manual of Style (16^th Edition):

Othman, Enas Azhar. “Gas Hydrate Equilibrium Measurements for Multi-Component Gas Mixtures and Effect of Ionic Liquid Inhibitors.” 2014. Masters Thesis, Texas A&M University. Accessed January 27, 2021. http://hdl.handle.net/1969.1/152653.

MLA Handbook (7^th Edition):

Othman, Enas Azhar. “Gas Hydrate Equilibrium Measurements for Multi-Component Gas Mixtures and Effect of Ionic Liquid Inhibitors.” 2014. Web. 27 Jan 2021.

Vancouver:

Othman EA. Gas Hydrate Equilibrium Measurements for Multi-Component Gas Mixtures and Effect of Ionic Liquid Inhibitors. [Internet] [Masters thesis]. Texas A&M University; 2014. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/1969.1/152653.

Council of Science Editors:

Othman EA. Gas Hydrate Equilibrium Measurements for Multi-Component Gas Mixtures and Effect of Ionic Liquid Inhibitors. [Masters Thesis]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/152653

Queens University

23. Choi, Julie. Towards an Understanding of Ice and Hydrate Adsorption by an Antifreeze Protein from Lolium Perenne .

Degree: Biology, 2015, Queens University

URL: http://hdl.handle.net/1974/13562

► Lolium perenne (Lp), the perennial ryegrass, produces an antifreeze protein (AFP) when seasonal temperatures and levels of available sunlight drop in the autumn. This protein,… (more)

Subjects/Keywords: Gas Hydrate ; Green Inhibitor ; Antifreeze Protein ; Ice Affinity ; Clathrate Hydrates

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APA (6^th Edition):

Choi, J. (2015). Towards an Understanding of Ice and Hydrate Adsorption by an Antifreeze Protein from Lolium Perenne . (Thesis). Queens University. Retrieved from http://hdl.handle.net/1974/13562

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Choi, Julie. “Towards an Understanding of Ice and Hydrate Adsorption by an Antifreeze Protein from Lolium Perenne .” 2015. Thesis, Queens University. Accessed January 27, 2021. http://hdl.handle.net/1974/13562.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Choi, Julie. “Towards an Understanding of Ice and Hydrate Adsorption by an Antifreeze Protein from Lolium Perenne .” 2015. Web. 27 Jan 2021.

Vancouver:

Choi J. Towards an Understanding of Ice and Hydrate Adsorption by an Antifreeze Protein from Lolium Perenne . [Internet] [Thesis]. Queens University; 2015. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/1974/13562.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Choi J. Towards an Understanding of Ice and Hydrate Adsorption by an Antifreeze Protein from Lolium Perenne . [Thesis]. Queens University; 2015. Available from: http://hdl.handle.net/1974/13562

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

24. Omelchenko, Roman 1987-. Analysis of the Development of Messoyakha Gas Field: A Commercial Gas Hydrate Reservoir.

Degree: MS, Petroleum Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/148428

► Natural gas is an important energy source that contributes up to 25% of the total US energy reserves (DOE 2011). An increase in natural gas… (more)

Subjects/Keywords: Development; Messoyakha; Gas hydrates

…1 1.1. Brief overview of the history of gas hydrates… …1 1.2. Gas hydrates as a potential source of energy… …3 1.3. Review of the current state of gas hydrates R&D projects and resources development… …technologies of gas from gas hydrates. ............ 13 1.5. Literature review and scope of the study… …Figure 5 - (a) Cross section showing the lateral and vertical extent of gas hydrates…

10 more images…

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APA (6^th Edition):

Omelchenko, R. 1. (2012). Analysis of the Development of Messoyakha Gas Field: A Commercial Gas Hydrate Reservoir. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/148428

Chicago Manual of Style (16^th Edition):

Omelchenko, Roman 1987-. “Analysis of the Development of Messoyakha Gas Field: A Commercial Gas Hydrate Reservoir.” 2012. Masters Thesis, Texas A&M University. Accessed January 27, 2021. http://hdl.handle.net/1969.1/148428.

MLA Handbook (7^th Edition):

Omelchenko, Roman 1987-. “Analysis of the Development of Messoyakha Gas Field: A Commercial Gas Hydrate Reservoir.” 2012. Web. 27 Jan 2021.

Vancouver:

Omelchenko R1. Analysis of the Development of Messoyakha Gas Field: A Commercial Gas Hydrate Reservoir. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/1969.1/148428.

Council of Science Editors:

Omelchenko R1. Analysis of the Development of Messoyakha Gas Field: A Commercial Gas Hydrate Reservoir. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/148428

25. Le, Thi Xiu. Etude expérimentale des propriétés mécaniques et de la microstructure des sédiments contenant des hydrates de méthane : Experimental study on the mechanical properties and the microstructure of methane hydrate-bearing sandy sediments.

Degree: Docteur es, Géotechnique, 2019, Université Paris-Est

URL: http://www.theses.fr/2019PESC1039

► Les hydrates de méthane (MHs), composés de gaz de méthane et d’eau, se forment naturellement à haute pression et faible température dans les sédiments marins… (more)

▼ Les hydrates de méthane (MHs), composés de gaz de méthane et d’eau, se forment naturellement à haute pression et faible température dans les sédiments marins ou pergélisols. Ils sont actuellement considérés comme une ressource énergétique (principalement MHs dans les sédiments sableux) mais aussi une source de géo-hasards et du changement climatique (MHs dans les sédiments grossiers et fins). La connaissance de leurs propriétés mécaniques/physiques, qui changent considérablement avec la morphologie et distribution des hydrates dans les pores, est très importante pour minimiser les impacts environnementaux liés aux futures exploitations du gaz de méthane à partir des sédiments sableux contenant des MHs (MHBS). La plupart des études expérimentales concernent MHBS synthétiques à cause des difficultés pour récupérer des échantillons intacts. Différentes méthodes ont été proposées pour former MHs dans les sédiments au laboratoire pour reconstituer des sédiments naturels, mais sans grand succès. Cette thèse a pour objectif d’évaluer la morphologie, la distribution des MHs dans les MHBS synthétiques à différentes échelles et d’étudier les effets des MHs (leur morphologie et teneur en hydrate) sur les propriétés mécaniques des MHBS. Deux méthodes de formation d’hydrates dans les sédiments sableux ont été proposées. Au niveau macroscopique, la distribution des hydrates au niveau des pores est évaluée en se basant sur la vitesse de propagation d’onde de compression (mesurée et calculée à partir des modèles existants). Des essais triaxiaux ont été utilisés pour étudier l’influence des MHs à différentes teneurs en hydrate sur les propriétés mécaniques des MHBS. Par ailleurs, l’Imagerie par Résonance Magnétique a été utilisée pour étudier la cinétique de formation/dissociation d’hydrates et aussi la distribution des hydrates sur l’ensemble de l’échantillon. Les résultats montrent qu’un cycle de température en conditions non drainées complète la redistribution des hydrates dans les pores après la saturation en eau de l’échantillon à haute teneur en hydrate. La distribution des hydrates sur l’ensemble de l’échantillon devient plus homogène avec la saturation en eau suivie par un cycle de température. En outre, les propriétés mécaniques des sédiments augmentent avec l’augmentation de la teneur en hydrate.A l’échelle du grain, la tomographie aux rayons X (XRCT) et celle au Synchrotron XRCT (SXRCT, Synchrotron SOLEIL) ont été utilisées pour observer la morphologie et la distribution des MHs au niveau des pores des sédiments sableux. Ce travail n’a pas été facile car il nécessitait des dispositifs expérimentaux compliqués (pour maintenir la haute pression et faible température) mais aussi en raison du faible contraste entre MHs et l’eau sur les images de XRCT, SXRCT. Des dispositifs spécifiques ont été développés pour étudier la formation d’hydrates, la morphologie et la distribution à l’échelle du grain des MHs en utilisant XRCT, SXRCT. De plus, une nouvelle méthode a été développée pour déterminer plus précisément les fractions… Advisors/Committee Members: Tang, Anh-Minh (thesis director).

Subjects/Keywords: Hydrates de méthane; Sédiments sableux; Formation/Dissociation d'hydrates; Morphologie des hydrates; Distribution des hydrates; Propriétés mécaniques; Gas hydrates; Sandy sediments; Gas hydrate formation/dissociation; Gas hydrate morphology; Gas hydrate distribution; Mechanical properties; 624.151

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Le, T. X. (2019). Etude expérimentale des propriétés mécaniques et de la microstructure des sédiments contenant des hydrates de méthane : Experimental study on the mechanical properties and the microstructure of methane hydrate-bearing sandy sediments. (Doctoral Dissertation). Université Paris-Est. Retrieved from http://www.theses.fr/2019PESC1039

Chicago Manual of Style (16^th Edition):

Le, Thi Xiu. “Etude expérimentale des propriétés mécaniques et de la microstructure des sédiments contenant des hydrates de méthane : Experimental study on the mechanical properties and the microstructure of methane hydrate-bearing sandy sediments.” 2019. Doctoral Dissertation, Université Paris-Est. Accessed January 27, 2021. http://www.theses.fr/2019PESC1039.

MLA Handbook (7^th Edition):

Le, Thi Xiu. “Etude expérimentale des propriétés mécaniques et de la microstructure des sédiments contenant des hydrates de méthane : Experimental study on the mechanical properties and the microstructure of methane hydrate-bearing sandy sediments.” 2019. Web. 27 Jan 2021.

Vancouver:

Le TX. Etude expérimentale des propriétés mécaniques et de la microstructure des sédiments contenant des hydrates de méthane : Experimental study on the mechanical properties and the microstructure of methane hydrate-bearing sandy sediments. [Internet] [Doctoral dissertation]. Université Paris-Est; 2019. [cited 2021 Jan 27]. Available from: http://www.theses.fr/2019PESC1039.

Council of Science Editors:

Le TX. Etude expérimentale des propriétés mécaniques et de la microstructure des sédiments contenant des hydrates de méthane : Experimental study on the mechanical properties and the microstructure of methane hydrate-bearing sandy sediments. [Doctoral Dissertation]. Université Paris-Est; 2019. Available from: http://www.theses.fr/2019PESC1039

University of Otago

26. Fraser, Douglas. Seismic characterisation of hydrate and shallow gas systems associated with active margin sediments and structures in the Pegasus Basin, Hikurangi Margin, New Zealand .

Degree: University of Otago

URL: http://hdl.handle.net/10523/7372

► The Pegasus Basin off the east coast of New Zealand's North Island is a frontier basin that hosts a large gas hydrate province. The basin… (more)

▼ The Pegasus Basin off the east coast of New Zealand's North Island is a frontier basin that hosts a large gas hydrate province. The basin has a large amount of faulting, which has lead to the creation of many interesting and unique accumulations of gas hydrates. In 2009/2010, petroleum industry standard 2D seismic data were acquired across the basin by New Zealand Petroleum and Minerals (a New Zealand government agency) to generate interest in exploration of this basin for conventional oil and gas. This seismic data set presents an unique opportunity to examine the basin's gas hydrate systems with the aim of determining the economic potential of the gas hydrates in the basin while improving our understanding of how observed gas hydrate features were formed. The seismic data were reprocessed to optimise the imaging of features related to gas hydrates. When the data were examined, there were numerous gas hydrate features found, so only a selection are presented in this thesis. With the assistance of seismic attributes, Bottom Simulating Reflections (BSRs) and blanking zones are examined. High-density velocity analysis is used to characterise areas of hydrate (higher velocity) and free gas (lower velocity). The high-density velocity analysis proved to be a very effective technique for examining the structure of gas migration chimneys. Two of the most interesting features identified in the data set include a blank dome shape with a gas chimney at its centre and a text book hydrate/free gas phase reversal that is examined in detail using amplitude vs offset (AVO) and inversion analysis techniques. The model for fluid flow and how the free gas from a chimney at the centre of the blanking zone is converted to hydrate is discussed. The hydrate and free gas phase reversal that is observed was formed by localised fluid flowing from depth into the gas hydrate stability zone (GHSZ). As the BSR becomes shallower, the sea floor deepens at this location. Without a localised fluid flow, the BSR would increase in depth with the increasing depth of the sea floor. Gas hydrate saturation and volumetric analyses were performed for one target. Concentrations were determined using empirical saturation formulae, confirming a potential target. The question of how much gas hydrate potentially is present in the basin, is discussed based both my work and that of others. Advisors/Committee Members: Gorman, Andrew (advisor).

Subjects/Keywords: gas hydrates; Pegasus Basin; seismic

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APA (6^th Edition):

Fraser, D. (n.d.). Seismic characterisation of hydrate and shallow gas systems associated with active margin sediments and structures in the Pegasus Basin, Hikurangi Margin, New Zealand . (Doctoral Dissertation). University of Otago. Retrieved from http://hdl.handle.net/10523/7372

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Chicago Manual of Style (16^th Edition):

Fraser, Douglas. “Seismic characterisation of hydrate and shallow gas systems associated with active margin sediments and structures in the Pegasus Basin, Hikurangi Margin, New Zealand .” Doctoral Dissertation, University of Otago. Accessed January 27, 2021. http://hdl.handle.net/10523/7372.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

MLA Handbook (7^th Edition):

Fraser, Douglas. “Seismic characterisation of hydrate and shallow gas systems associated with active margin sediments and structures in the Pegasus Basin, Hikurangi Margin, New Zealand .” Web. 27 Jan 2021.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Vancouver:

Fraser D. Seismic characterisation of hydrate and shallow gas systems associated with active margin sediments and structures in the Pegasus Basin, Hikurangi Margin, New Zealand . [Internet] [Doctoral dissertation]. University of Otago; [cited 2021 Jan 27]. Available from: http://hdl.handle.net/10523/7372.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Council of Science Editors:

Fraser D. Seismic characterisation of hydrate and shallow gas systems associated with active margin sediments and structures in the Pegasus Basin, Hikurangi Margin, New Zealand . [Doctoral Dissertation]. University of Otago; Available from: http://hdl.handle.net/10523/7372

Note: this citation may be lacking information needed for this citation format:
No year of publication.

University of Manchester

27. Campbell, Benedict Louis. Seismic Characterisation of Gas Hydrates in the Luderitz Basin, Offshore Namibia: Investigating Shallow Heat Flow and Fluid Flow Phenomena.

Degree: 2018, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313126

► The identification of gas hydrate accumulations and their associated fluid flow phenomena is important to both petroleum exploration and climatic scientists. They provide insight into… (more)

Subjects/Keywords: Gas Hydrates; Hydrate Pingos; Heat Flow; Buried pingos; Cold-water corals

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APA (6^th Edition):

Campbell, B. L. (2018). Seismic Characterisation of Gas Hydrates in the Luderitz Basin, Offshore Namibia: Investigating Shallow Heat Flow and Fluid Flow Phenomena. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313126

Chicago Manual of Style (16^th Edition):

Campbell, Benedict Louis. “Seismic Characterisation of Gas Hydrates in the Luderitz Basin, Offshore Namibia: Investigating Shallow Heat Flow and Fluid Flow Phenomena.” 2018. Doctoral Dissertation, University of Manchester. Accessed January 27, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313126.

MLA Handbook (7^th Edition):

Campbell, Benedict Louis. “Seismic Characterisation of Gas Hydrates in the Luderitz Basin, Offshore Namibia: Investigating Shallow Heat Flow and Fluid Flow Phenomena.” 2018. Web. 27 Jan 2021.

Vancouver:

Campbell BL. Seismic Characterisation of Gas Hydrates in the Luderitz Basin, Offshore Namibia: Investigating Shallow Heat Flow and Fluid Flow Phenomena. [Internet] [Doctoral dissertation]. University of Manchester; 2018. [cited 2021 Jan 27]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313126.

Council of Science Editors:

Campbell BL. Seismic Characterisation of Gas Hydrates in the Luderitz Basin, Offshore Namibia: Investigating Shallow Heat Flow and Fluid Flow Phenomena. [Doctoral Dissertation]. University of Manchester; 2018. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313126

University of Ottawa

28. Sarah, Oddy. Effect of Phase-Contacting Patters and Operating Conditions on Gas Hydrate Formation .

Degree: 2014, University of Ottawa

URL: http://hdl.handle.net/10393/31414

► Research into hydrate production technologies has increased in the past years. While many technologies have been presented, there is no consensus on which reactor design… (more)

▼ Research into hydrate production technologies has increased in the past years. While many technologies have been presented, there is no consensus on which reactor design is best for each potential application. A direct experimental comparison of hydrate production technologies has been carried out in between a variety of reactor configurations at similar driving force conditions. Three main reactor types were used: a stirred tank, a fixed bed and a bubble column and compared different phase contacting patterns for the stirred tank and bubble column. In the initial phase of hydrate formation in a stirred tank, formation was mass and heat transfer limited at the lower stirring speed, and heat transfer limited at the higher stirring speed. After more than 10% of the water had been converted to hydrate, formation was mass transfer limited regardless of the other conditions. Neither the use of a gas inducing impeller, nor a 10 wt% particle slurry significantly affected hydrate formation rates; however, the particle slurry did lower the induction time. Due to the poor scale-up of impeller power consumption in a stirred tank, a semi-batch fixed bed was studied since it does not require any power input for mixing. The significantly slower rates of formation observed in the semi-batch fixed bed, as well as the lost reactor capacity to particles, mean that this type of system would require a much larger reactor. Faster volume and power normalized rates of hydrate formation were observed in the bubble column than in a stirred tank at similar mass transfer driving force conditions. Higher conversions of water to hydrate were observed in the bubble column because mixing was accomplished by bubbling gas from the bottom rather than by an impeller. The highest conversions of water and gas were achieved during a later stage of accelerated hydrate formation, indicating an optimal hydrate fraction for continuously operated bubble column reactors. The second stage of hydrate formation occurred more frequently at higher gas flowratess. Therefore, the increased water conversion and single-pass gas conversion justify the increased energy input required by the higher gas flowrate. Balancing the rates of mass transfer and heat removal was also critical for optimal bubble column as insufficient mass transfer would result in a lower rate of formation and insufficient heat transfer would cause previously formed hydrates to dissociate. The addition of 10wt% glass beads to the reactor promoted hydrate formation; however, it did not do so sufficiently to make up for the loss in reactor capacity or the increased energy requirement.

Subjects/Keywords: Gas Hydrates; Phase-Contacting Patterns; Reactor Design; Bubble Column; Stirred Tank

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Sarah, O. (2014). Effect of Phase-Contacting Patters and Operating Conditions on Gas Hydrate Formation . (Thesis). University of Ottawa. Retrieved from http://hdl.handle.net/10393/31414

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Sarah, Oddy. “Effect of Phase-Contacting Patters and Operating Conditions on Gas Hydrate Formation .” 2014. Thesis, University of Ottawa. Accessed January 27, 2021. http://hdl.handle.net/10393/31414.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Sarah, Oddy. “Effect of Phase-Contacting Patters and Operating Conditions on Gas Hydrate Formation .” 2014. Web. 27 Jan 2021.

Vancouver:

Sarah O. Effect of Phase-Contacting Patters and Operating Conditions on Gas Hydrate Formation . [Internet] [Thesis]. University of Ottawa; 2014. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/10393/31414.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sarah O. Effect of Phase-Contacting Patters and Operating Conditions on Gas Hydrate Formation . [Thesis]. University of Ottawa; 2014. Available from: http://hdl.handle.net/10393/31414

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Swedish University of Agricultural Sciences

29. Ahmadi Moghaddam, Elham. Life cycle assessment of novel biomethane systems.

Degree: 2019, Swedish University of Agricultural Sciences

URL: https://pub.epsilon.slu.se/16012/

► Climate mitigation and supply of renewable energy are global challenges. The main cause of climate change is anthropogenic activities, including consumption of fossil energy sources… (more)

▼ Climate mitigation and supply of renewable energy are global challenges. The main cause of climate change is anthropogenic activities, including consumption of fossil energy sources and land use change. Biomethane, a biomass-derived renewable energy carrier, is interchangeable with fossil-based natural gas and can provide energy services (e.g. heat, electricity and vehicle fuel) and high-value products such as chemicals. However, the availability of feedstock suitable for anaerobic digestion, the limited grid infrastructure in certain regions and problems relating to storage and distribution are barriers to increased deployment of biomethane systems. This thesis aims to provide decision support for the development and implementation of future biomethane systems, by describing the energy performance and climate impact of some promising novel technologies related to biomethane production, conversion of biomethane to high-value products and biomethane distribution in a life cycle perspective. Anaerobic digestion of maize and pyrolysis of willow for production of biomethane were assessed and compared, while gas-to-liquid (GTL) technologies were studied as potential routes for conversion of biomethane to liquid transportation fuels or platform chemicals. Gas hydrates were assessed as a means of biomethane distribution. The results showed that transition from maize-based anaerobic digestion to willowbased pyrolysis for biomethane production improved energy performance (higher external energy ratio) and environmental performance (lower climate impact), mainly due to buildup of soil organic carbon and use of biochar as a soil amendment or as an energy source to replace fossil coal. Use of biomethane for production of dimethyl ether as a GTL fuel was competitive relative to the conventional compressed biomethane system regarding energy performance and climate impact. Formation and disassociation of gas hydrates was associated with high energy use, and thus technological development is required to overcome the high primary energy inputs and related high climate impact of gas hydrate distribution.

Subjects/Keywords: biomethane,; pyrolysis; biochar; GTL products; gas hydrates; life cycle; climate impact

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APA (6^th Edition):

Ahmadi Moghaddam, E. (2019). Life cycle assessment of novel biomethane systems. (Doctoral Dissertation). Swedish University of Agricultural Sciences. Retrieved from https://pub.epsilon.slu.se/16012/

Chicago Manual of Style (16^th Edition):

Ahmadi Moghaddam, Elham. “Life cycle assessment of novel biomethane systems.” 2019. Doctoral Dissertation, Swedish University of Agricultural Sciences. Accessed January 27, 2021. https://pub.epsilon.slu.se/16012/.

MLA Handbook (7^th Edition):

Ahmadi Moghaddam, Elham. “Life cycle assessment of novel biomethane systems.” 2019. Web. 27 Jan 2021.

Vancouver:

Ahmadi Moghaddam E. Life cycle assessment of novel biomethane systems. [Internet] [Doctoral dissertation]. Swedish University of Agricultural Sciences; 2019. [cited 2021 Jan 27]. Available from: https://pub.epsilon.slu.se/16012/.

Council of Science Editors:

Ahmadi Moghaddam E. Life cycle assessment of novel biomethane systems. [Doctoral Dissertation]. Swedish University of Agricultural Sciences; 2019. Available from: https://pub.epsilon.slu.se/16012/

30. Amos, Daniel Michael. High pressure hydrates of CO2 & materials for carbon storage.

Degree: PhD, 2015, University of Edinburgh

URL: http://hdl.handle.net/1842/21031

► The class of water-ice compound known as gas hydrate has been of interest to science for sometime where, for instance, gas hydrates make excellent candidates… (more)

▼ The class of water-ice compound known as gas hydrate has been of interest to science for sometime where, for instance, gas hydrates make excellent candidates for studying the interactions of water and gas molecules. They are also of relevance to industry, where they present an interesting material for the separation, transport, and storage of different gases, and also due to the vast quantities of methane gas that are trapped in natural gas hydrate formations. While much is known about the behaviour of many gas hydrate systems at high-pressure, the CO2 hydrate system is less well studied, with apparent hydrate dissociation at just 10 kbar, and (prior to this work) an unsolved crystalline phase in the pressure range 6-10 kbar. In this work the CO2-H2O system has been studied at high-pressure and, by heating samples to the liquid state and observing their behaviour on refreezing, it has been confirmed that there are indeed no hydrate phases in the system above 10 kbar (up to at least 40 kbar). While performing this investigation, an interesting effect of CO2 on the behaviour of water crystallisation was also observed, and additionally, a simple yet effective technique for making solubility measurements in the system at high-pressure has been discovered. Using a combination of neutron and x-ray diffraction techniques, the crystal structure of the previously unsolved ‘HP’ CO2 hydrate phase has been determined by ab-initio methods. It has been found to be a new gas hydrate structure, but is shared by a small number of Zintl compounds, and may also be common to the unsolved C0 phase of H2 hydrate. The structure has a characteristic spiral of guest molecule sites, leading to its suggested label as the spiral hydrate structure (s-Sp). Its composition has been measured as a tri-hydrate, and the compressibility of s-Sp and the low-pressure s-I CO2 hydrate phases have also been measured. On cooling to 77 K it has been discovered that a third CO2 hydrate phase is formed with a significantly larger unit cell, which is thought to possess a structure similar to that of s-Sp, but with an ordered arrangement of CO2 molecules. Finally, a pilot study of the high-pressure behaviour of the binary H2-CO2 hydrate system has been performed. Using Raman spectroscopy it has been found that a new mixed hydrate phase exists in the pressure range 5-15 kbar, and it is speculated that this could exhibit a freely tunable H2/CO2 content, based on suspicion that it forms the s-Sp structure. Additionally, it has been found that H2 and CO2 chemically react at room temperature, when compressed to ~5 kbar in a rhenium gasket. From the Raman spectrum this reaction product has been identified to be aqueous-methanol.

Subjects/Keywords: 665; high-pressure; gas hydrates; CO2; neutron diffraction; charge flipping

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APA (6^th Edition):

Amos, D. M. (2015). High pressure hydrates of CO2 & materials for carbon storage. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/21031

Chicago Manual of Style (16^th Edition):

Amos, Daniel Michael. “High pressure hydrates of CO2 & materials for carbon storage.” 2015. Doctoral Dissertation, University of Edinburgh. Accessed January 27, 2021. http://hdl.handle.net/1842/21031.

MLA Handbook (7^th Edition):

Amos, Daniel Michael. “High pressure hydrates of CO2 & materials for carbon storage.” 2015. Web. 27 Jan 2021.

Vancouver:

Amos DM. High pressure hydrates of CO2 & materials for carbon storage. [Internet] [Doctoral dissertation]. University of Edinburgh; 2015. [cited 2021 Jan 27]. Available from: http://hdl.handle.net/1842/21031.

Council of Science Editors:

Amos DM. High pressure hydrates of CO2 & materials for carbon storage. [Doctoral Dissertation]. University of Edinburgh; 2015. Available from: http://hdl.handle.net/1842/21031

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