Sub-sea well injection system

摘要

A slurry of oil-impregnated cuttings from the use of oil based drilling mud and other unwanted slurries and fluids may be injected into the annulus of a sub-sea well and then into a porous formation through which the well has passed using apparatus on a guide base surrounding the sub-sea well head. The guide base comprises a coupling for a pipe extending down from the drilling rig, a one-way isolation valve and pipework leading to the outermost housing of the well. The outermost housing has ports to carry the slurry into the outermost annulus and inner housings may also have ports to carry this slurry into inner annuli. Inter housings also have a one-way check valve to control the injection. The guide base may have a cement circulation pipework and a cement and dump valve. The guide base may also be a retrievable base so that the injection apparatus may be reused.