Publication Date:
2016-12-21
Description:
Injection of CO2 into CH4-hydrate bearing sediments, and the resulting in-situ replacement of
CH4-hydrate by CO2-hydrate, has been proposed as a technique for the emission-free production
of natural gas from gas hydrates. While the hydrate conversion is thermodynamically feasible,
many studies conclude that the overall process suffers from mass transfer limitations and CH4
production is limited after short time. To improve CH4 production various technical concepts
have been considered, including the injection of heated supercritical CO2 combining chemical
activation and thermalstimulation.
While the feasibility of the concept was demonstrated in high-pressure flow-through experiments
and high CH4 production efficiencies were observed, it was evident that overall yields and
efficiencies were influenced by a variety of processes which could not be disclosed through bulk
mass and volume analysis. Here we present different numerical simulation strategies which were
developed and tested as tools to better understand the importance of mass and heat transport
relative to reaction and phase transition kinetics for CH4 release and production, or for CO2
retention, respectively. The modeling approaches are discussed with respect to applicability for
experimental design, process development or prediction of CH4 production from natural gas
hydrate reservoirs on larger scales.
Type:
Conference or Workshop Item
,
NonPeerReviewed
Format:
text
