Abstract:

The serious coking in disengager in 1.4 Mt/a RFCC unit of Daqing Branch of CNPC limited the long-term operation. The analysis on the post-riser system and the stripper of the unit indicated that the open-type structure of the exit-tube of primary cyclone separator without pre-stripping device led to a long residence time of oil and gas in the disengager and coking; the structure defects and single stripping technology of stripping section were the another important reason for the coking in disengager. The technologies of SVQS (oil and gas quick separation system) and MSCS (high efficiency stripping combination technology) developed by China University of Petroleum (Beijing) were employed to revamp the disengager. The results show that the light oil yield increases 3.46 percentage points, and the liquid yield increases 1.44 percent points, while the coke yield decreases 1.43 percentage points, and the unit energy consumption reduces by 41.5 MJ/t.

Key words: RFCC, post-riser system, stripper, SVQS, MSCS