South Korean refiner S-Oil signed a 15-year liquefied natural gas supply contract with Malaysia’s Petronas, the company said Friday.

Under the contract, S-Oil will start importing 700,000 tons of LNG per year from April 2018 to April 2033.

“With the latest deal, the company has secured fuel for facilities in Ulsan, which previously used Bunker C as their main fuel sources. The company plans to substitute Bunker C with LNG so that a larger amount of Bunker C can be spared to produce more lucrative products,” an S-Oil spokesperson said.

The Bunker C will be processed at the residue upgrading complex and olefin downstream complex that S-Oil is currently building in Ulsan, it said.

S- Oil previously invested a total of some 4.8 trillion won ($4.25 billion) for the project involving the residue upgrading and olefin downstream complexes. The construction is expected to be completed in April next year.

Details and prices of the contract remained undisclosed by the company.

By Shim Woo-hyun (ws@heraldcorp.com)