Tank cleaning turns circular in Abqaiq

Cleaning a giant 180,000-barrel oil tank is industrial housekeeping on a colossal scale.

Tank cleaning innovation is seeing previously wasted resources now reused. 

Oil processing occupies the bigger part of the plant, and the oil processing facility uses 18 stabilizer columns to conduct final gas separation and removal of hydrogen sulfide. 

Stabilized oil is sent to Ras Tanura and Jubail on the East Coast, and Yanbu’ in the west, and excess quantities of stabilized oil is stored in 14 tanks.

At each turnaround and inspection cycle, the tanks are cleaned to remove buildup.

Maintenance engineer Saad K. Alharbi explains that once the tank is empty, a small quantity of fresh heated oil is introduced to liquefy the built-up sludge remaining in the tank.

“Pumps move the liquefied sludge into a recirculation module for filtration and oil separation, before the entire liquid is pumped out to a nearby line,” said Alharbi. “After the sludge is removed, the tank’s floor and wall are cleaned.”

Impressively, about 1,800 cubic meters of oil is recovered from each tank.

CAPTION:  The roof of Abqaiq Plants tank “T-814” is lowered as the tank has been emptied in preparation for cleaning, which will see the recovery of about 1,800 cubic meters of oil, previously discarded as waste.