Tank Stabilisation

The application of polymer injection to stabilise a gas oil dye marker tank at a refinery in Grangemouth has allowed the tank to remain in commission and site production to continue without disruption.

While the tank itself was originally built on a secure piled base, the bund surround had been placed on a concrete basewhich had begun to subside – probably in part due to the low water table and intermittent flooding. If settlement continued, there there was a potential for a loss of bund integrity and stress on the tank nozzles and pump pipework.

“One option available was the insertion of traditional driven piles, a time-consuming and expensive method which had the potential to disrupt production,” says Billy Fulton, remediation engineer, Hydrocarbons, who recommended a second option - the use of Uretek polymer injection.

Working alongside the Hydrocarbon team, the 3-man Uretek squad first marked a 1.5m grid on the concrete bund and then drilled 15mm diameter holes ot allow the injection of the expanding polymers to the fill the voids below the slab and stabilise the bund.

 “From induction to job completion, the Uretek team took only 3 ½ days to successfully and safely complete the process,” says Billy Fulton. “They performed the job very professionally and conscientiously throughout. Not only did polymer injection deliver savings of 90% over the cost of piling, but the process was completed in a fraction of the time and site operations were able to continue unaffected.”