Dual-density drilling with riser gas lift

摘要

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.