Huntsman Corp. has begun preliminary engineering work that will increase the MDI production capacity of its Geismar complex by about 80 percent.

The company will increase the facility’s production of methylene diphenyl diisocyanate by 440,000 tons. Huntsman said expanding at Geismar will allow the company to capitalize on significant advantages, including access to U.S. shale gas and a strong logistics base.

It will take at least six months and possibly as much as a year before Huntsman can make “a real definitive statement” about the number of jobs the expansion will create or the cost for the project, said Mark Dearman, operations director for Huntsman Polyurethanes Americas and site manager for Geismar.

“It is a significant project. Four hundred kilotons is a significant investment and set of assets, no doubt about it,” Dearman said.

In March, Huntsman announced it was spending $78 million to add 55,000 tons of MDI production at the Geismar plant, giving it a total capacity of 550,000 tons. That project was expected to add 17 full-time jobs and support 100 construction jobs. That additional capacity is expected to come onstream in 2015.

The proposed new capacity is expected to be online in 2018 and will allow Huntsman to further support the growth of its customers worldwide.

MDI is used in making polyurethanes, a key component in car seats, furniture, footwear adhesives and energy-saving insulation products.

“Shale gas has significantly improved the economics of investing in U.S. facilities and has helped our Geismar facility to establish a strong cost leadership position. The planned additional capacity will reinforce this position and establish the plant as a truly global supplier,” said Anthony P. Hankins, president of Huntsman Polyurethanes.

Huntsman’s 760-acre Geismar site already is the largest integrated MDI production facility in the Americas region.

The demand for MDI-based polyurethanes is growing at about 8 percent a year, Hankins said. Huntsman Polyurethanes is investing in projects globally to support its customers.

In addition to its Geismar facility, Huntsman Polyurethanes operates MDI facilities at its sites in Rotterdam, Netherlands, and Shanghai.