Abstract:The thermal-stimulation test conducted on the JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate production research well in March of 2002 was designed to increase the in situ temperature of a portion of a well defined and constrained gas hydrate reservoir above the gas hydrate stability point, while maintaining constant pressure. Data collected, including surface and downhole instrumentation readings and data from advanced logging and seismic programs, were then used to calibrate numerical gas hydrate reservoirsimulation models and determine the kinetic and thermodynamic properties of the in situ gas hydrate.The thermal-stimulation test was successful: bottomhole temperature was increased to greater than 50°C during the test; gas from dissociated gas hydrate was produced, sampled, and flared at surface; and significant amounts of real-time downhole temperature and pressure data, as well as other scientific measurements, were obtained. L'essai de stimulation thermique a été une réussite : on a pu accroître la température au fond du puits à plus de 50°C durant l'essai; on a produit, échantillonné et brûlé à la surface du gaz naturel provenant de la dissociation des hydrates de gaz; et on a généré, entre autres données scientifiques, une quantité considérable de mesures de température et de pression, acquises en temps réel dans le puits.
Analysis and interpretation of the thermal test of gas hydrate dissociation in the JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate production research well Abstract:The objectives of this study were to 1) analyze the data from a field test of thermally induced dissociation of gas hydrate in the JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate production research well; 2) validate and calibrate the numerical model; and 3) determine important parameters describing gas hydrate behaviour and dissociation. The initial conditions and properties of the gas hydrate deposit were determined using supporting geological and geophysical data. Direct measurements provided the necessary boundary conditions. The numerical model was calibrated against the cumulative volumes of produced gas, a process that increased confidence in the model. Two possible scenarios of thermal dissociation, using unadjusted and smoothed data, are proposed to interpret the field test results. The parameters of the dominant physical processes are estimated by inverse modelling (history matching). Their results compare favourably with previously published data. Additionally, estimates of long-term production are made, and an alternative well configuration is proposed to substantially increase gas production.
The first sustained production of methane from gas hydrate was achieved at the Mallik site over a 6-day period during March 2008, as part of a co-operative research and development effort by the Japan Oil, Gas and Metals National Corporation and the Geological Survey of Canada, a part of Natural Resources Canada. Basic operational parameters, such as gas/water flow rates and bottom-hole flowing pressure and temperature, were continuously recorded throughout the production period. These data have enabled subsequent history matching, interpretation, and long-term production forecasting of the Aurora/JOGMEC/NRCan Mallik 2L-38 test well. In this work, a numerical history matching of the Mallik 2L-38 field test is conducted utilizing a single-well radial model with appropriate gridding choices. Importantly, our investigation reveals that the assumption of conventional gas-flow behaviour in a producing gas hydrate reservoir is inadequate for explaining the pattern of gas production observed during the Mallik test. A new gas-evolution model with characteristics similar to gas exsolution via depressurization of heavy oil is applied to successfully history match the Mallik production data. Utilizing our base-case history match, we assess the effects and relative importance of reservoir heterogeneity, thermal conductivity, salinity, and permeability. The effect of reservoir extent (radial boundary distance) on long-term gas production is also explored. Overall, long-term gas hydrate production from the Mallik reservoir appears feasible, assuming sufficient internal continuity of the deposit, such that effective limits to production will depend on the location of the effective outer boundary of the resource.
Finite-element geothermal models were used to compare the sensitivity of arctic subpermafrost gas hydrate at the Mallik borehole to temperate marine gas hydrate located offshore southwestern Canada. Considering the thermal signal alone accompanying the end of the last ice age, a 30 m gas-hydrate-bearing layer (porosity 51%, hydrate saturation 20%) at the base of gas hydrate stability 13.5 ka ago in the temperate marine environment would have disappeared by the present. In contrast, the same gas-hydrate-bearing layer underlying permafrost would persist until at least 4 ka after present, even with contemporary climate warming. These longer times for subpermafrost gas hydrate arise from thawing pore ice at the base of permafrost, at the expense of dissociation of the deeper gas hydrate. Overlying permafrost thus buffers the dissociation of underlying gas hydrate from climate surface warming.
Preface The JOGMEC/NRCan/Aurora Mallik 2007-2008 Gas Hydrate Production Research Well Program is the third major research-and-development endeavour carried out since 1998 at the Mallik site in the Mackenzie Delta of Canada's Northwest Territories. In just over a decade, the research enabled through these programs has literally moved a new energy field from unproven scientific concepts to proof-of-concept for a safe and sustainable method to produce gas hydrate, a unique and unusual solid form of natural gas. While there have been many contributors from around the world during each program, one constant has been the leadership provided by Japan and Canada. For Japan, the research forms part of a national strategy to secure a new domestic energy resource from the production of marine gas hydrate deposits that are found in abundance off its coasts. The Ministry of Economy, Trade, and Industry, through the Research Consortium for Methane Hydrate Resources in Japan (MH21 Research Consortium), has assigned the responsibility for guiding much of this research to the Japan Oil, Gas and Metals National Corporation. In Canada, Natural Resources Canada has led the research and development studies aimed at quantifying and evaluating the energy potential of the permafrost gas hydrate deposits in the Arctic, and marine gas hydrate deposits off Canada's coasts. The most recent field program has also included, for the first time, a lead agency from the north. Aurora College, an agency of the Government of the Northwest Territories, has acted as the Designated Operator for the program, responsible for all field activities. The 15 technical research papers and accompanying databases presented in this publication comprise the third Geological Survey of Canada bulletin on Mallik gas hydrate research-and-development endeavours. With more than 100 peer-reviewed papers compiled in these volumes, they chronicle a truly remarkable record of scientific accomplishment and fulfil the intent of Canada and Japan to undertake our gas hydrate research and development for the benefit of all. Without doubt, the highlight of this phase of the research has been to establish proof-of-concept for a simple and effective gas hydrate production technique. From a broader perspective, however, the body of work we advanced has also addressed many scientific unknowns and thereby improved techniques for quantifying the distribution of gas hydrate in nature, and understanding its physical properties and the role it plays in ongoing natural geological processes. We are indebted to the many hundreds of scientists, engineers, and workers who have contributed tirelessly to move an entirely new energy field forward.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.