The completion of Trains A and B, now entering pre-commissioning and system testing, will push the unit's daily processing capacity from 160,000 barrels to its full design capacity of 320,000 barrels a day, according to Iran's Petroleum Engineering and Development Company (PEDEC).

Mohsen Paknejad, Iran's oil minister, has called the CTEP unit one of the key pieces of infrastructure needed to develop oil fields in West Karoun, a region along Iran's border with Iraq that includes the shared South and North Azadegan, Yadavaran, and North and South Yaran fields. Boosting output from shared fields, he said, requires more than new wells — it requires processing capacity to match.

The facility separates water and salt from crude oil, stabilizes it, and prepares it for shipment through the West Karoun pipeline network. It also includes infrastructure to capture and process associated gas, work aimed at cutting the volume of gas burned off at flares and improving efficiency.

Nasrollah Zarei, PEDEC's managing director, described the completion of Trains A and B as a turning point for the project. The unit's main structure is now finished, he said, with attention shifting to associated gas processing and compression facilities.

The project's first two trains, C and D, came online in December, delivering an initial 160,000 barrels a day of processing capacity. Officials said work continued through Iran's 12-day war with Israel this year despite delays in importing some equipment, including two separator units.

Once associated gas facilities are complete, officials said, the unit is expected to route roughly 200 million cubic feet of gas per day to the nearby Gas and NGL 3200 plant, reducing flaring and recovering feedstock for downstream use.

PEDEC projects that total processing capacity across West Karoun's fields will reach 820,000 barrels a day once the CTEP project is fully complete, a threshold officials say is central to Iran's broader plans to raise crude output.