Assessment of methane gas production from Indian gas hydrate petroleum systems

• Published in: Applied energy Vol. 168; pp. 649 - 660
• Main Authors: Vedachalam, N., Ramesh, S., Srinivasalu, S., Rajendran, G., Ramadass, G.A., Atmanand, M.A.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.04.2016
• Subjects: Assessments; Depressurization; Gas hydrate; Gas hydrates; Hydrates; India; Marine settings; Matlab; Methane; Natural gas; Pressure drop; Reservoirs; Thermal; TOUGH + HYDRAT; ISW, India, Andhra Pradesh, Krishna; Methane; Gas hydrate; Marine settings; TOUGH+HYDRAT; Depressurization; Thermal
• ISSN: 0306-2619; 1872-9118
• DOI: 10.1016/j.apenergy.2016.01.117

•Methane gas extraction methodology studied for Indian gas hydrate reservoirs.•Effectiveness of in-situ electro-thermal stimulation and depressurization techniques analyzed.•Results from modeling and simulation with MATLAB and TOUGH+HYDRATE presented.•Depressurization technique could dissociate laterally up to 145m from well bore in KG basin.•In-situ electro-thermal stimulation found to be economical in KG and Andaman reservoirs. The effectiveness of the electro-thermal and depressurisation based techniques applied to three marine gas hydrate reservoir settings of India is modeled and simulated using MATLAB and TOUGH+HYDRATE reservoir modeling software. The results indicate that the depressurisation technique (with an achievable ΔP of >90bar) will be effective in dissociating gas hydrates up to 145m from a well bore in the Krishna Godavari (KG) reservoir. The technique when applied to the Andaman and Mahanadi reservoirs is found to produce a maximum ΔP of 64 and 70bar against the minimum required threshold of 134 and 152bar, and hence, found to be less effective for hydrate dissociation. The in-situ electro-thermal technique will be effective in the KG and Andaman reservoirs; and in the Mahanadi reservoir, if the gas hydrate saturations are >17%. The depressurization technique when applied to a hypothetical sandy reservoir in the KG basin shows that the spatial pressure drop is nearly double that in a clayey setting, which is conducive for hydrate dissociation.