Hashemi said about 1,300 temporary workers were hired to assist the refinery’s own maintenance teams in carrying out the extensive overhaul, which began on Oct. 27. “More than 2,000 personnel worked continuously in day and night shifts to complete the overhaul process,” he told Shana.

The refinery, one of Iran’s key energy complexes, undertook repairs on its atmospheric and vacuum distillation units, southern liquefied gas and Merox units. The maintenance aimed to extend equipment life, enhance operational safety, improve fuel quality and reduce environmental emissions.

Despite limited time and energy supply constraints, the Tehran refinery completed the turnaround in just 18 days—five days shorter than in previous years. Ali-Hashemi said the operation relied heavily on domestic expertise, advanced technology, and tight coordination across engineering, inspection, operations, and repair teams.

“Our top priority was completing the overhaul on schedule while maintaining safety and high-quality standards,” Ali-Hashemi said.

Zero-Accident Overhaul

The maintenance manager emphasized that the entire overhaul process was completed without any accidents. “Inspection, engineering, and operations teams maintained strict oversight of the repair process to ensure the refinery could operate safely and continuously for at least the next four years,” he said.

According to Hashemi, roughly 800 workers worked during the day and 300 at night in rotating shifts. In addition to the refinery’s 800 in-house technicians, 1,300 day laborers were recruited to meet the workload. “Every department, whether directly or indirectly, contributed to the success of this critical overhaul,” he added.

Among the completed works were the opening and refurbishment of 79 heat exchangers, replacement of three packing layers in one of the unit’s towers, extensive piping and welding operations, upgrades to desalting units and furnaces, and repairs on multiple pieces of process equipment.

Following the overhaul, the refinery expects a slight increase in production of its main products—gasoline, diesel and jet fuel.

$126,000 Daily Profit From Distillation Unit

Ali-Hashemi underlined the financial significance of maintaining the distillation unit, describing it as a “profit-generating engine” of the refinery. “The distillation unit, with a capacity of 126,000 barrels per day, generates about $126,000 in daily profit for the Tehran refinery,” he said.

He added that timely and precise repairs play a vital role in maintaining production stability and ensuring the quality of refined products.

Ali-Hashemi also noted that the refinery relied entirely on local technology and equipment for this turnaround. “Our biggest challenge was the race against time,” he said. “All units taken offline for repairs had to be brought back into service within 18 days. Any delay could have affected product output and caused serious energy imbalances.”

The successful completion of the Tehran refinery’s major overhaul underscores Iran’s growing reliance on domestic engineering capacity and modern maintenance management to sustain stable fuel production under tight deadlines.