关键词: 催化裂化装置, 催化剂, 钠中毒, 电脱盐, 置换, 钝化剂和助剂

Abstract: Sodium poisoning occurred in the FCC units of three refineries due to the increase of sodium content in the balance agent to about 11 000 μg/g. The slurry yield of FCC unit in refinery Z increases, the activity of FCC equilibrium agent in refinery F decreases from 67.4% to 52.4%, and the light oil yield decreases from 79.87% to 76.44%. In Z refinery, by replacing the new electric desalting equipment and using balance agent replacement, the content of sodium and vanadium in the balance agent is reduced, and the slurry yield is reduced by 1.3%. Due to the poor properties of feedstock in F refinery, when the unit consumption of fresh agent is increased to 5.5 kg/t, the sodium content in the equilibrium agent had no obvious change, the activity is restored to 62.0%, and the light oil yield is restored to 78.3%, which can maintain a good product distribution. Due to the low metal content in the equilibrium agent in J refinery, the vanadium content is 1 000 μg/g, the activity and performance of the balancing agent can be well maintained by increasing the catalyst unit consumption to 1.0 kg/t. Through the analysis, strengthening the electric desalting, using catalyst replacement, using anti metal additives and so on can effectively prevent and deal with catalyst sodium poisoning accidents.

Key words: FCCU, catalyst, sodium poisoning, electric desalting, replacement, passivators and additives