The Antwerp fire brigade said Friday that the fire aboard the car carrier Silver Sky was under control, but pockets of smoldering material remained active.
The fire broke out early on Thursday on the ship's seventh deck, and it spread through the eighth and ninth decks before it was brought under control. The condition of the remaining compartments is unknown but significant cargo damage is expected.
The crew were safely evacuated at the outset and no injuries were reported.
On Thursday, the department placed tugs and shoreside fire trucks to spray cooling water onto the hull, and it called in Safety Zeeland's Marine Incident Response Group (MIRG). The specialized government unit hoped to use a Cobra lance to penetrate the vessel's holds and extinguish the fire.
The Cobra uses an abrasive slurry jet cutting system to puncture a bulkhead, then injects a fine mist at high pressure. It is a relatively established technology, with over 1,000 incident responses on record, and it eliminates much of the risk associated with entering a space to fight a fire. But Antwerp's firefighters told local media that they decided not to use it because the Sky's holds were larger than they believed the system could accommodate.
Instead, according to two Belgian media sources, they turned to a different solution: injecting 140 tons of CO2 into the holds to smother the fire.
The department did not specify whether the gas was from the vessel's own fixed firefighting system or from an external source, but the amount would represent more than 3,000 bottles of the four-foot-tall, 100-pound size used in most shipboard CO2 cylinder banks.
As of Friday, areas of the vessel continued to smolder and a small detachment of firefighters remained on scene to spray cooling water onto the hull.