Dual-Density Drilling Systems Reduce Deepwater Drilling Costs: Part Ⅰ-Concepts and Riser Gas Lift Method

摘要

Development of the U.S. deepwater gas resources is limited by the high capital costs involved in developing these resources. Dual-gradient drilling methods have been proposed as a means to provide simpler, safer, more economic well designs and therefore increase the ultimate development and utilization of deepwater gas resources. Two dual-density drilling concepts - riser dilution with a low density liquid and riser gas lift - were investigated as potential means to implement a dual-gradient system. The overall objective was to establish whether further research concerning dual-density drilling systems based on use of low-density fluids, either liquid or gas, is justified. The investigation was conducted by the Craft and Hawkins Department of Petroleum Engineering at Louisiana State University and sponsored by the Research Partnership to Secure Energy for America.