Riser-less managed pressure drilling with subsea fluid handling

Abstract

A well drilling system can include a drill string free of a riser string enclosing the drill string, a rotating control device assembly connected above a subsea wellhead and sealing about the drill string, and a fluid return line connected to the rotating control device assembly. The fluid return line is configured to flow fluid from the rotating control device assembly without the fluid being flowed to the drilling rig. A method of drilling can include drilling a wellbore without a riser connected between a subsea wellhead and a drilling rig, the drilling including sealing about a drill string with a rotating control device assembly, flowing fluid into the wellbore during the drilling, and returning the fluid from the wellbore during the drilling. The fluid remains subsea after the flowing step and during the drilling step.

Dependencies are inferred from the claim text.