Snohvit CO2 storage project: Assessment of CO2 injection performance through history matching of the injection well pressure over a 32-months period

摘要

A performance assessment study of the Snohvit CO2 project, where approximately 1.1 million tonnes of CO2 have been injected into a fault segment of the Snohvit' field was carried out. Since the start of CO2 injection, the injection well pressure has risen at a rate faster than what is sustainable for a 25-years expected lifetime of the project. An important element of the history matching effort is the incorporation of fluvial facies in the reservoir model to reflect the sedimentary environment in the sandstone Tubaen formation. With the help of 4D seismic analysis, excellent match to both the flowing and shut-in bottom-hole pressure data throughout a 32-months injection period have been obtained. The outcomes of this study suggest that the fluvial depositional environment, together with the fact that the injection well is situated in a fault-segment, have contributed to a significant reduction in the injectivity at F2H.