Abstract:

The debutanizer of No.2 cracking unit of the ethylene plant in Maoming had been operated for a long time. The unsaturated olefins in the feed polymerized at high temperature and blocked the trays, reducing the separation effect of the debutanizer. As a result, the loss rate of C4 in the bottom of debutanizer increased. To solve the high C4 loss in the debutanizer, the process flow was revamped by utilizing the idle post depentanizer of the No.2 cracking gasoline hydrogenation unit. The debutanizer and the post depentanizer were operated in series, and the material from the bottom of the debutanizer was used as the feed to the depentanizer to further separate and recover C4, thus greatly reducing the loss rate of high value-added C4 products and improving the economic benefit.

Key words:  ')">

 , revamping of post depentanizer, tray blocking, C4 yield