Gas production from hydrate resevoirs

Download
index.pdf
2005
Alp, Doruk
Show full item record
199
views
86
downloads
In this study; gas production by depressurization method from a hydrate reservoir containing free gas zone below the hydrate zone is numerically modeled through 3 dimensional, 3 phase, non-isothermal reservoir simulation. The endothermic nature of hydrate decomposition requires modeling to be non-isothermal; hence energy balance equations must be employed in the simulation process. TOUGH-Fx, the successor of the well known multipurpose reservoir simulator TOUGH2 (Pruess [24]) and its very first module TOUGH-Fx/Hydrate, both developed by Moridis et.al [23] at LBNL, are utilized to model production from a theoretical hydrate reservoir, which is first studied by Holder [11] and then by Moridis [22], for comparison purposes. The study involves 2 different reservoir models, one with 30% gas in the hydrate zone (case 1) and other one with 30% water in the hydrate zone (case 2). These models are further investigated for the effect of well-bore heating. The prominent results of the modeling study are: · In case 1, second dissociation front develops at the top of hydrate zone and most substantial methane release from the hydrate occurs there. · In case 2 (hydrate-water in the hydrate zone), because a second dissociation front at the top of hydrate zone could not fully develop due to high capillary pressure acting on liquid phase, a structure similar to ice lens formation is observed. · Initial cumulative replenishment (first 5 years) and the replenishment rate (first 3.5 years) are higher for case 2 because, production pressure drop is felt all over the reservoir due to low compressibility of water and more hydrate is decomposed. Compared to previous works of Holder [11] and Moridis [22], amount of released gas contribution within the first 3 years of production is significantly low which is primarily attributed to the specified high capillary pressure function.
Engineering design.
http://etd.lib.metu.edu.tr/upload/12606241/index.pdf
https://hdl.handle.net/11511/15224
Graduate School of Natural and Applied Sciences, Thesis

Suggestions

Analyses of factors affecting acceptance of homecare technologies by patients with chronic diseases
Kutlay, Ayşegül; Mumcuoğlu, Ünal Erkan; Department of Medical Informatics (2012)
In this study, the factors affecting the acceptance of mobile homecare system were examined. These factors were assessed by taking Unified Theory of Acceptance and Use of Technology (UTAUT) as a theoretical model. The main feature of this thesis (differing from the other studies in the literature) is that the user acceptance study model is analyzed on a system that is not realized yet. So, this study has two dfferent perspectives. The first one is the examination the results of UTAUT for a system in the des...
Separation of unburned carbon from fly ash using a concurrent flotation column
Altun, Naci Emre; Hwang, J Y (Elsevier BV, 2009-12-01)
In this study. a new concurrent flotation column that simulates the plug flow reactor was designed with the use of a static mixer, a froth separator column and an optional additional bubble generator for fly ash beneficiation. The objective was to improve the efficiency and effectiveness of unburned carbon removal from fly ash by minimizing energy costs. Cleaning tests were performed with and without the additional bubble genarator. Without the additional bubble generator unburned carbon in the ash product ...
CO2 emissions of Turkish manufacturing industry: A decomposition analysis
Akbostancı Özkazanç, Elif; Tunç, Gül İpek (2011-06-01)
In this study. CO2 emissions of Turkish manufacturing industry are calculated by using the fuel consumption data at ISIC revision 2, four digit level. Study covers 57 industries, for the 1995-2001 period. Log Mean Divisia Index (LMDI) method is used to decompose the changes in the CO2 emissions of manufacturing industry into five components: changes in activity, activity structure, sectoral energy intensity, sectoral energy mix and emission factors. Mainly, it is found that changes in total industrial activ...
Investigation of turbulence models used in automotive industry
Taştan, Umur; Çetinkaya, Tahsin Ali; Department of Mechanical Engineering (2011)
In this study; reliability and performance of turbulence models used in CFD softwares to determine the aerodynamics of passenger cars, are tested and compared. In the analyses, drag forces acting on the car, pressure and velocity distributions and wake flow patterns are determined by using several turbulence models with a commercial software Fluent. Calculated results compared to the experimental results given in the literature. It is observed that, turbulence models give relatively reliable results for det...
Inconsistencies (problems of) between two dimensional graphics of (urban) design and its three dimensional (urban) forms
Eren, Ebru; Barlas, Mehmet Adnan; Urban Design in City and Regional Planning Department (2013)
This study concentrates in particular on (good) visuality and visual perception of any design with consequences on urban environments and human lives. The purpose is that ‘any design requires not only holism (wholeness) within itself, which is generated by its design parameters, but also co-relation (consistency) between its mental imageries (visualizations or conceptual-mental fictions) and all their representational products in each and every dimensional realms. The design process is conducted respectfull...
Citation Formats
D. Alp, “Gas production from hydrate resevoirs,” M.S. - Master of Science, Middle East Technical University, 2005.
METU IIS - Integrated Information Service open@metu.edu.tr