Patent ID: 8316945

Claim:
A method of removing fluid from an oil well in a marine environment, the oil well having a well bore with a longitudinal axis, a riser, and a drill string inside the riser, the method comprising the following steps: (a) attaching a swivel to the drill string, the swivel including a mandrel and a sleeve, the sleeve being rotatably connected to the mandrel, the sleeve including at least one catch for an annular seal of an annular blowout preventer, the sleeve being longitudinally reciprocable relative to the mandrel; (b) inserting the swivel into the riser, the riser being in fluid communication with the well bore; (c) connecting the riser and well bore to an annular blowout preventer, the annular blowout preventer having an annular seal the connection being made by closing the annular seal on the sleeve, the annular blow-out preventer being located at a first level, the riser and well bore being at least partially filled with a first fluid, the first fluid being at a level in the riser which is above the first level, the at least one catch restricting longitudinal movement of the sleeve relative to the annular blow out preventer when a high differential pressure exists above and below the closed annular seal, the high differential pressure placing a longitudinal force on the sleeve along the longitudinal axis, and which force attempts to push the sleeve outside of the closed annular seal; (d) the swivel and annular blowout preventer separating the first fluid into an upper section of the first fluid that is located above the first level, and a lower section of the first fluid that is located below the first level; (e) displacing a portion of the lower section of the first fluid; and (f) displacing a portion of the upper section of the first fluid.