5. Vacuum Flashing

Question 1

■ Process Description & Objective?

Answer 1

■
▪ Distillation at reduced pressure.
▪ Separate straight run residue without causing cracking.
▪ Reducing pressure will reduce boiling point of compounds which will help to separate straight run residue into more cuts without cracking molecules.

Question 2

■ Feedstock and products?

Answer 2

■
▪ Straight run residue
│
– Light Flashed Distillate (Flasher Tops) — Cat Cracking
– Heavy Flashed Distillate (Flasher Tops) — Cat Cracking

▪ Flasher Bottoms (Highest concentration of sulphur) — 
│
– Feed to an asphalt Plant
– A thermal cracker
– A Coker
– Blending component for residual fuel