Flint Hills Resources has announced a $250 million upgrade to the West Plant refinery in Corpus Christi that will enhance the refinery's abilities to produce cleaner-burning fuels and process heavier crudes.

The company announced last week that it will add a new sulfur recovery unit and build a diesel desulfurization unit, making the construction project the company's largest in Corpus Christi since 1995.

The two projects are expected to take 18 months to complete and cost more than $250 million.

Company officials said the sulfur recovery unit will allow the refinery to handle additional feedstocks to improve its competitive position. The diesel desulfurization unit will afford opportunities to upgrade low-value products into high-value products, such as ultra low-sulfur diesel.

"We are committed to efficiently providing quality products to our customers," said Joe Coco, executive vice president of operations for Flint Hills Resources. "With the addition of these two new units, we will enhance our ability to produce ultra low-sulfur diesel for a growing Texas market. In addition, we will gain flexibility when it comes to efficiently processing heavier and sour crudes."

Construction is scheduled to begin this fall and is expected to require help from contractors employing about 500 workers at peak periods.

"We have been a part of the Corpus Christi community since 1981 and we've continued to enhance our ability to serve customers in that time," said Phil Gaarder, vice president and manufacturing manager for the Texas refinery. "We were the first to introduce low-sulfur gasoline in Central Texas in 2001. When this capital project is completed, we will have spent about $3 billion on acquisitions and capital expansions, many of which have resulted in significant improvements in our ability to produce cleaner-burning fuels and reduce emissions."

Company officials said the Corpus Christi refining complex is among the nation's lowest-emitting refineries. They said the latest data indicates the complex emits 0.09 pounds of commonly regulated substances per barrel of crude oil refining capacity, while the industry average is 0.19 pounds per barrel of refining capacity.

Koch Refining Co., the predecessor of Flint Hills Resources, acquired Kerr-McGee Corp.'s Southwestern Refinery on Nueces Bay Boulevard in 1995. The facility is now Flint Hills Resources' East Plant.

Both sites are operated as one transportation fuels and aromatic chemicals complex of about 900 employees, with a 300,000-barrel-per-day capacity because of the construction of a Central Control Center and pipelines connecting both facilities.

In 2001, the refinery began producing low-sulfur gasoline for the Texas market following a $32 million project. In 2002, Flint Hills spent an additional $145 million on projects that further increased the amounts of low-sulfur fuels produced and marketed.