By Erwin Seba
HOUSTON (Reuters) - The nation's largest refinery hit a throughput milestone last week, processing 615,000 barrels in one day for the first time since a series of setbacks that followed its $10 billion expansion, sources familiar with operations said.
Two years ago, around the time of its opening ceremony,it was predicted the Port Arthur, Texas plant of Motiva Enterprises [MOTIV.UL] would slowly gain efficiencies and by now would be routinely running 630,000 to 660,000 barrels per day (bpd).
Instead, the plant run by Royal Dutch Shell and Saudi Aramco [SDABO.UL] often runs below its stated capacity of 600,000 bpd at a time when refiners are processing rising volumes of crude in the U.S. energy boom.
The 2.5 percent increase in crude oil intake one day in late June, trumpeted in a company email, showed the continuing impacts of a troubled start-up after the expansion, the sources said.
"If it had been built better, if it had been designed better, it could be running more crude," said one of the sources.
A Motiva official declined to comment.
The U.S. Energy Information Administration late last month said the Port Arthur refinery should be able to run at 620,000 barrels per stream day in 2014, the maximum amount a plant can process under optimal operating conditions.
Not long after the April 2012 startup of the refinery's new 325,000 bpd crude distillation unit called VPS-5, a quick fix evolved into a series of problems that eventually shut the VPS-5 for seven and half months. (http://tinyurl.com/7fh42nq)
Those included a week of work to replace potentially leaky valves on a pipe on VPS-5 that allowed caustic sodium hydroxide being pumped into the unit.
When VPS-5 was heated for an early June 2012 restart, the sodium hydroxide, used by refiners to enable the processing of crude, was vaporized. This caused the scoring and pitting of piping throughout the unit. Two small fires broke out when Motiva attempted to put crude oil through it.
It has only inched towards running at capacity in the past few months as the company found ways to overcome an unrelated vibration problem on a five-foot diameter pipe feeding crude into the unit.
The sources said Motiva has weighed replacing the pipe and has looked at 2015 as a possible time for that work, possibly in the first quarter of next year.
Motiva already plans a seven-week overhaul in January and February of 2015 on the 90,000 bpd gasoline-producing fluidic catalytic cracking unit (FCC), the sources said.
The top of the main column on the FCC will be cut off to replace the unit’s reactor. Motiva is building the replacement reactor on the grounds of the refinery. Also, the continuous catalytic reformer will be shut while the FCC is down.
The refinery has planned to include work on the 200,000 bpd VPS-4, but some of the work was done in June while a hydrotreater was shut. VPS-4, like the other CDUs at the refinery, does initial refining of crude oil coming into the plant and provides feedstock for all other units. VPS-4 supplies gasoil to the FCC.
The refinery does not have plans for unit overhauls in the fall of 2014, but may do some short refits like the hydrotreater work in June.
On Wednesday, the Port Arthur refinery restarted a diesel hydrotreater following a small fire on Tuesday, the sources said. There were no injuries.
(Reporting By Erwin Seba; Editing by Terry Wade and David Gregorio)