RockSolid Thermite based barrier

Offentlig prosjektsammendrag

Interwell P&A have since 2012 been working on a radically different approach for abandoning wells. The technology has the potential to replace traditional cement plugs with an artificial rock that extends from formation to formation. The goal for the project is to create formation-to-formation barriers across multiple casing strings using only wireline. This means that an abandonment can be performed without the use of a drilling rig, since none of the casing strings, nor the tubing, need to be pulled from the well. The barrier requires two wireline runs to be installed. First, an anchor with a heatshield material is placed at the correct depth in the well and will act as a base for the barrier installation. The anchor will be installed at a depth where there is competent formation outside the casing (caprock). Secondly, a cylinder containing a heat generating exothermic mixture is lowered into the well and parked on top of the anchor/heatshield. The reaction is started via an electric signal through the e-line. The chemical mix will combust and start a chemical reaction that gives of a lot of heat (up to 3000 deg C). The molten mix will melt the tool, along with the wellbore elements outside the tool (casing/tubing/cement/control lines, etc). The end result is that the casing strings have been melted in a length of a few meters, and a cross-sectional artificial rock has been created. The barrier will bond to the cap-rock through a crystallization process, similar to naturally occurring magma intrusions in the earth’s crust. The technology development is per date (Aug 2018) in the piloting phase, where 8 wells have been performed so far. Currently, only one casing string is being melted. The technology will be developed to allow melting of two or more concentric tubulars, expected second half of 2019.