* S-Oil to build $4.7 bln refining, petchem plant -KNOC
* S-Oil was a sole bidder for land offered at 519 bln won
* Sales contract to be signed this week -KNOC spokesman (Adds S-Oil's filing to stock exchange)
By Meeyoung Cho
SEOUL, Feb 18 (Reuters) - South Korea's third-largest refiner, S-Oil Corp, has won a tender to buy land from state-run Korea National Oil Corp (KNOC) to build a refining and petrochemical facility worth at least 5 trillion won ($4.72 billion).
S-Oil paid 519 billion won for 92 hectares (227 acres) of land and was the sole bidder, a KNOC spokesman said. The refiner also confirmed winning the tender for the land in a filing to the stock exchange on Tuesday.
A final sales contract will be signed later this week, said the KNOC spokesman. S-Oil had been regarded as the most likely buyer after reports that it had been asking the government for help getting land for projects.
An industry source familiar with the matter said that S-Oil is planning to build a refining and petrochemical facility, although the investment details would be finalised later in a board of directors meeting.
One of the tender requirements was that potential bidders received approval from their board of directors for a refinery or petrochemical plant worth at least 5 trillion won.
S-Oil is reported to be considering expanding its paraxylene operations. Paraxylene, used to make clothing and plastic bottles, is produced by processing naphtha, a refined product of crude oil or condensates.
The South Korean refinery already has a 740,000-tonnes-per-year paraxylene plant as part of its refinery and petrochemical operations.
A spokesman for S-Oil declined to comment on any project details.
The land the refiner is buying is more than 300 km southeast of the capital Seoul, in Ulsan, where S-Oil has its 669,000-barrels-per-day refining facility.
S-Oil's largest shareholder is Aramco Overseas Co B.V., a unit of Saudi Arabian Oil Company (Aramco). It has a 35 percent stake.
($1 = 1060.4 Korean won) (Reporting by Meeyoung Cho; Editing by Ed Davies and Tom Hogue)