July 01, 2026 [Zawya]- Saudi-listed National Industrialisation Company (Tasnee) has completed construction of the ethylene cracker expansion project at the Saudi Ethylene and Polyethylene Company (SEPC) in Al Jubail Industrial City and has commenced pilot production.

The company disclosed the milestone in a filing to the Saudi stock exchange on Wednesday.

SEPC is a joint venture between Tasnee Sahara Olefins Company (TSOC) and US-based LyondellBasell. Tasnee holds a 60 percent stake in the venture.

Tasnee awarded the engineering, procurement and construction (EPC) contract for the project, valued at approximately $500 million, to South Korea’s SGC E&C (formerly SGC eTEC) in December 2023.

At the time of the award, the company said the expansion would increase olefins production at the ethylene cracker by 18 percent.

Prior to the expansion, the plant had a nameplate production capacity of 1 million tonnes per year of ethylene and 285,000 tonnes per year of propylene.