-- Valero Energy's (VLO) 415,000 b/d Port Arthur refinery is gradually restoring operations more than a month after a Mar. 23 explosion disrupted output, Wood Mackenzie said Thursday.
The blast damaged the diesel hydrotreater DHT-243, forcing a plant-wide shutdown and triggering phased recovery efforts as operators began restarting select processing units.
Wood Mackenzie tracked progress using aerial surveillance and infrared monitoring, which showed reconstruction underway alongside sequential unit restarts across the facility, it said.
The refinery restarted its fluid catalytic cracker on Apr. 26 and began ramping up its largest crude unit the same day, though utilization remains below normal levels, Wood Mackenzie added.
Operators have ramped up major units, including a 265,000 b/d crude distillation unit and a 172,000 b/d vacuum distillation unit, which are currently increasing throughput, though not yet at full capacity.
Several units have restarted, including a 150,000 b/d CDU and a 48,000 b/d VDU on April 2; hydrocrackers of 57,000 b/d and 45,000 b/d on April 3 and April 15; and an 80,000 b/d FCC on April 26, while a 47,000 b/d diesel hydrotreater and a sulfur recovery unit remain offline.
The explosion also disrupted the adjacent Diamond Green renewable diesel plant, which depends on refinery utilities, though it resumed operations later in March, Wood Mackenzie added.
Initial damage assessments showed the diesel hydrotreater sustained the most severe impact, with collapsed structures and extensive piping deformation across the unit.
Nearby units experienced lighter damage, while two cooling towers and a control room within the blast zone suffered more significant structural impacts, Wood Mackenzie said.
Repair crews have focused on rebuilding the cooling towers, with cranes, scaffolding, and dismantling work visible as contractors replaced damaged components.
Despite progress, multiple units remained offline as of Apr. 27, including parts of the refinery's largest crude distillation system, limiting output recovery, according to Wood Mackenzie.
The prolonged outage has tightened regional fuel markets, as the loss of 415,000 b/d capacity coincides with geopolitical tensions affecting global supply balances, Wood Mackenzie added.
Wood Mackenzie said its combined aerial and field monitoring will continue tracking restart timelines and operational recovery across the refinery.