Rock-breaking experiment with supercritical carbon dioxide jet

Key words:  carbon dioxide  supercritical fluid  jet  rock-breaking  drilling and completion

Abstract:

Drilling with supercritical carbon jet is an unconventional oil and gas reservoirs drilling and production method with great potential. The supercritical carbon jet experimental system was developed based on the basic characteristics of supercritical carbon dioxide combined with ihe actual drilling and completion technology features. The rock-breaking experiment was carried out with the experimental system. The results show that the rock-breaking ability of supercritical carbon dioxide jet is much better than the high pressure water jet. The effect of the nozzle diameter, standoff distance, jet pressure and rock parameter on ihe rock-breaking ability of supercritical carbon dioxide jet agrees well with that of high pressure water jet, while the effect of bottom-hole temperature on the rock-breaking ability of supercritical carbon dioxide jet is very marked. And the rock-breaking effect shaiply increases as the increase of jet temperature and the increase trend reflects a slowing decline after the temperature exceeding the critical value.