07 August 2017
Astrimar awarded Innovate UK funding
Astrimar to support RECL qualifying Bismuth alloys as an alternative to cement plugs for well abandonment
Permanent well abandonment implies that materials used for plugging of wells should provide a seal against leakage from the well for millions of years. Cement plugs have traditionally been accepted; however, these are time consuming and hence costly to install and have unknown integrity over such extended durations.
Rawwater Engineering (RECL) are currently devloping Bismuth alloys as a cost effective alternative for plugging and abandonment of wells. The high corrosion resistance, low melting point and expansion properties of the alloys can be exploited to cast high integrity, in-situ seals including in underwater environments, within soil and also within porous rock. The alloys can be used as a reversible replacement for cement grout seals with signficantly shorter installation times. The overall objective of this Expanding Metal Seal Project is to extend Rawwater's existing capabilities in the handling and deployment of low melting point metals in defined smooth wall geometries (i.e. well abandonment casing plugs) and to develop tools to create seals in undefined and/or rough walled geometries (e.g. cap rock) that cannot be perfectly sealed with existing technologies.
Current industry guidelines recommend qualification testing to demonstrate a plug life of at least 3000 years. As part of the project, Astrimar is developing predictive well integrity modelling software to forecast future plug performance, reflecting the specific downhole casing / rock formation conditions and plug material behaviour, to support well risk assessments and provision of plug reliability assurance. In addition, Astrimar will be supporting the RECL qualification testing activities.