Challenges, Uncertainties and Issues Facing Gas Production from Hydrate Deposits in Geologic Systems

Abstract

The current paper complements the Moridis et al. (2009a) review of the status of the effort toward commercial gas production from hydrates. We aim to describe the concept of the gas hydrate petroleum system, to discuss advances, requirement and suggested practices in gas hydrate prospecting and GH deposit characterization, and to review the associated technical, economic and environmental challenges and uncertainties, including: the accurate assessment of producible fractions of the GH resource, the development of methodologies for identifying suitable production targets, the sampling of hydrate-bearing sediments and sample analysis, the analysis and interpretation of geophysical surveys of GH reservoirs, well testing methods and interpretation of the results, geomechanical and reservoir/well stability concerns, well design, operation and installation, field operations and extending production beyond sand-dominated GH reservoirs, monitoring production and geomechanical stability, laboratory investigations, fundamental knowledge of hydrate behavior, the economics of commercial gas production from hydrates, and the associated environmental concerns. SPE 131792A review paper by Moridis et al. (2009a) summarized the status of the effort for production from gas hydrates. The authors discussed the distribution of natural gas hydrate accumulations, the status of the primary international research and development R&D programs (including current policies, focus and priorities), and the remaining science and technological challenges facing commercialization of production. After a brief examination of GH accumulations that are well characterized and appear to be models for future development and gas production, they analyzed the role of numerical simulation in the assessment of the hydrate production potential, identified the data needs for reliable predictions, evaluated the status of knowledge with regard to these needs, discussed knowledge gaps and their impact, and reached the conclusion that the numerical simulation capabilities are quite advanced and that the related gaps are either not significant or are being addressed. Furthermore, Moridis et al. (2009a) reviewed the current body of literature relevant to potential productivity from different types of GH deposits, and determined that there are consistent indications of a large production potential at high rates over long periods from a wide variety of hydrate deposits. Finally, they identified (a) features, conditions, geology and techniques that are desirable in the selection of potential production targets, (b) methods to maximize production, and (c) some of the conditions and characteristics that render certain GH deposits undesirable for production.Objectives. The current paper complements the Moridis et al. (2009a) review of the status of the effort toward commercial gas production from hydrates. Its objectives are to describe the concept of the gas hydrate petroleum system, to discuss advances, requirement and suggested practices in gas hydrate prospecting an...

A theoretical model for predicting the spatial distribution of gas hydrate dissociation under the combination of depressurization and heating without the discontinuous interface assumption

“…The reported in-situ tests of gas production from GH are carried out in Mackenzie Delta, Alaska North Slope, and Nankai Trough (Takahashi et al, 2003;Hancock et al, 2005;Kurihara et al, 2008;Moridis et al, 2011;ConocoPhillips, 2012;David, 2013). During these in-situ production tests, downhole pressures of the production wells in Mallik, Ignik Sikumi, and Nankai Trough are reduced from 11.2 MPa to 7.3 MPa (Kurihara et al, 2008;Moridis et al, 2011), 8.1-1.8 MPa (ConocoPhillips, 2012, and 13.5-4.5 MPa (David, 2013) respectively.…”

“…During these in-situ production tests, downhole pressures of the production wells in Mallik, Ignik Sikumi, and Nankai Trough are reduced from 11.2 MPa to 7.3 MPa (Kurihara et al, 2008;Moridis et al, 2011), 8.1-1.8 MPa (ConocoPhillips, 2012, and 13.5-4.5 MPa (David, 2013) respectively. Besides, the downhole temperature of Mallik 5L-38 well maintains at about 343 K (Takahashi et al, 2003;Hancock et al, 2005) to induce the GH dissociation.…”

Numerical Prediction of Seabed Subsidence with Gas Production from Offshore Methane Hydrates by Hot-Water Injection Method

“…Therefore, in March 2013,the first offshore MH production test was carried out by applying the depressurization method at the Eastern Nankai Trough, and approximately 120,000 m 3 of natural gas were produced in 6 days. Morid is et al(2010) [7] presented excellent reviews on the commercial gas production from MH reservoirs. Silpngarmlert et al(2012) [8] developed the compositional simulator for methanehydrate system, and they carried simulations applied by a constant bottom hole pressure implemented as a production scheme.…”

Testing a thermo‐chemo‐hydro‐geomechanical model for gas hydrate‐bearing sediments using triaxial compression laboratory experiments

“…Several methods have been proposed for production of natural gas from gas hydrate reservoirs, e.g., thermal stimulation, depressurization, and chemical activation ( [49,50], [53], [36]). Currently, depressurization is deemed the most mature approach.…”