Why is raffinate oil increasingly used as ethylene cracker feedstock in China?

Why is raffinate oil increasingly used as ethylene cracker feedstock in China?
Chinese integrated projects are shifting raffinate from blending into steam cracker feeds. The Quanzhou 1.5 million t/y ethylene project lists light naphtha, hydrocracking tail oil, aromatics raffinate and saturated LPG as cracking feedstock, producing polyolefins, EVA, butadiene and MTBE. The Gulei complex, after revising its energy review, will consume 1.91 million tons of naphtha annually while outputting 5.08 million tons of raffinate oil alongside raffinate C4 and C5 streams. This reflects a broader trend: as reformers maximize aromatics, the leftover paraffinic raffinate becomes a cheap, light cracker feed that improves ethylene yield versus heavier naphtha, tightening the merchant raffinate pool available to independent buyers.