At an average cost of £5M each, well abandonment is the biggest single decommissioning cost that North Sea operators currently face. This is because current practices require a rig to plug and abandon a well. This has prompted the search for new “rigless” abandonment techniques to lower costs.
Working with Heriot Watt University, OGIC and OGTC, Aubin has devised a new reservoir barrier technology called Xclude. It is safe, environmentally friendly and can be applied with existing equipment and without a rig.
Unlike existing techniques where a barrier is made in the well-bore, Aubin’s technique involves creating the barrier in the reservoir. The company’s Xclude technology takes scale formation - a problem the North Sea has faced for over forty years - and uses it to form a permanent mineral barrier in the rock, isolating any further hydrocarbon from entering the well.
Xcludes specially formulated fluids are easily mixed and deployed using standard pumping equipment. The scale inhibited solution can be pumped to various depths and is time-controlled to ensure that the scale forms where it is needed. By using this new approach Aubin believes operators could significantly reduce risk and cost.
Speaking about Xclude Paddy Collins, Aubin’s CEO said “Xclude was developed with extensive laboratory work collaborating with some of the leading scientists in the field. The technology is ready for field trials so that the industry can begin to see significant cost reductions in its P&A activities”.