07 March 2018
Astrimar awarded Innovate UK funding
Astrimar to support RECL in second project to qualify 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 developing a range of 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 seals with signficantly shorter installation times.
The overall objective of this "Advanced Bisthmuth Alloy Development for Downhole Casing and Plugging of Wells" project is to further develop and qualify an advanced Bisthmuth alloy for high pressure and high temperature applications which can be cast downhole to provide high integrity, cost effective well sealing and meet industry life requirements.
The parallel "Expanding Metal Seal" project started in August 2017 is focused on extending Rawwater's existing capabilities in the handling and deployment of low melting point metals for well casing plugs and to develop tools to create seals in undefined and/or rough walled geometries (e.g. cap rock) that are difficult to seal with existing technologies.
Current industry guidelines recommend qualification testing to demonstrate a plug life of at least 3000 years. As part of both projects, Astrimar is developing predictive well integrity modelling software to forecast future plug performance, reflecting the specific downhole well and casing 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.