Study on rock breakingwith supercritical CO2 jet and feasibility of ultra-short radius radial well drilling

Ultra-short radius radial well drilling is one of the critical ways to improve the recovery ratio and develop mature fields. However, due to the lagging development in drilling theory and related facilities, the technology are still encountering various bottlenecks such as difficulty in adding the thrust force, high pressure loss of the passing flow and low penetration rate, etc. Supercritical CO2 (SC-CO2) is recommended to be used in ultra-short radius radial well drilling because it will reduce the loss of hydraulic energy due to its low viscosity and no induced formation damage, as well as high rock-breaking rate at low threshold pressure. Based on analysis of the physical properties of SC-CO2 fluid and rock-breaking experiments with the jet, the advantages and feasibility of using SC-CO2 jet in ultra-short radius radial well drilling and implementation plan are illustrated. This study will further promote the development of ultra-short radius radial well drilling. ©, 2015, Northeastern University. All right reserved.