Motiva, a joint venture between Royal Dutch Shell and Saudi Aramco, recently
attempted to start operations at the expanded portion of the refinery and were met with trouble. Today we learned, according to various sources as well as Reuters, that the new expansion has been virtually ruined, and may be closed for repairs for months, or even a year or more.
You'll recall that June 14 we wrote how a small fire was impacting operations at the plant, and we had mentioned corrosion as a cause. After a second fire in virtually the same spot, refinery operators knew something was amiss with the plant. Upon further investigation, and now confirmed by Motiva, the plant will be down for a significant amount of time.
The expansion has been ruined by corrosion- pitting tanks, corroding stainless steel piping, fouling equipment, and will cost tens of millions to repair. In an amazing turn of events, shocking even experts in the industry, and yes- shocking me as well, perhaps just one barrel of caustic just brought down largest U.S. refinery.
a Reuters article,
While harmless when mixed with crude, the undiluted caustic vaporized into an invisible but devastating agent of corrosion as the chamber heated up to 700 degrees Fahrenheit (370 Celsius); the chemical gas raced through key units, fouled huge heaters and corroded thousands of feet of stainless steel pipe.
Then on Friday, prompted by questions from Reuters, Motiva spokeswoman Kayla Macke confirmed the contamination: "The preliminary inspection indicates that parts of the new unit have been contaminated with elevated levels of caustic."
While Motiva's VPS-5 was idling, authorities believe a few gallons each day of caustic leaked into the unit. The caustics are a base meant to negate the acid in cheaper heavy, sour crude that the new CDU was made to consume. They prevent residue from blocking pipes and reducing crude intake.
Normally, the amount leaked in the CDU would have been harmless, diluted by the crude. But only a small amount of hydrocarbon was circulating through the still while it was out of production, the normal method to maintain so-called "warm circulation" during a brief shutdown.
By the following weekend, unaware of the caustic incursion, Motiva began reheating the unit to resume operations; as the temperature reached 300 to 400 Fahrenheit, the caustic vaporized.
Ground zero was the atmospheric section, one of the simplest but most important machines in a modern plant. Although vast in scale, today's units are in many ways similar to the simple stills used to convert crude into kerosene for lamps at the start of the U.S. oil industry in the 1850s.
The core of any refinery, the main still boils crude at intense temperatures to split the hydrocarbon molecules into the initial components of fuels such as gasoline and diesel; the bulk of the output is an intermediate feedstock that requires further refining in a host of specialized secondary units.
Unlike a refinery blast, the misfortune unfolding at Motiva was relatively slow to materialize. The fires that erupted from small pipeline cracks that Saturday were small enough to be quickly extinguished by the workers on hand at the crude unit.
The extent of the damage was understood within two days.
"We have the worst-case scenario," one of the sources said. "Extensive damage throughout the crude unit. All of it."
Three engineering experts agreed that what one called "accelerated chemical corrosion" was rare, but not unheard of.
Motiva has begun hiring again at a feverish pace, looking to work on replacing the impacted parts as soon as possible. It must source replacement parts, cranes, and a significant amount of labor. While there's no timetable for completion, it seems ot be very urgent.
"They're really focused on the repairs," one of the sources close to refinery operations said. "They don't need to know the cause now. They've got 12 months to figure that out and fix it."
And while the unit is down, wholesale prices in the region have risen after it was understood that gasoline production in the region would not be what it was expected to be. Competing refineries in the area are sure to benefit from Motiva's problem. Perhaps after reading this story, some of our users will better understand just how complex these facilities can be.