Method for circulating a fluid entry out of a subsurface wellbore without shutting in the wellbore

摘要

A method for removing a fluid influx from a subsea wellbore drilled using a pump to return fluid from the wellbore to the surface. The method includes detecting the influx when a rate of the return pump increases. Flow from the wellbore is diverted from the return pump to a choke line when the influx reaches the wellhead. A choke in the choke line is operated so that a substantially constant bottom hold pressure is maintained while drilling fluid continues to be pumped through the drill sgring. Fluid flow from the wellbore is redirected to the return pump inlet when the influx has substantially left the well.

主权项

1. A method for removing a fluid influx from a wellbore, the wellbore drilled using a drill string having an internal passage therethrough, the wellbore having a wellhead disposed proximate a bottom of a body of water disposed thereabove, a fluid outlet of the wellbore coupled to an inlet of a mud return pump, an outlet of the return pump coupled to a return line to the water surface, the method comprising:
detecting the influx; diverting flow from the wellbore from the return pump to a choke line when the influx reaches the wellhead; operating a choke in the choke line so that a substantially constant bottom hole pressure is maintained, while continuing fluid flow into the drill string, the bottom hole pressure being less than a hydrostatic pressure that would be exerted by a column of the fluid flowing into the drill string from a surface of the water to a bottom of the wellbore; and redirecting fluid flow from the wellbore to the return pump inlet when the influx has substantially left the well.