关键词: 催化裂化, 催化剂跑损, 粒度分布, 流化性能, 微反活性, 产品分布

Abstract: Based on the data during the period of catalyst loss caused by the blocking in the dipleg of regenerator cyclone separator in company W, the effects of catalyst loss in the catalytic cracking unit on the particle size distribution of equilibrium catalyst, the fluidization of reaction regeneration system, the micro-activity of equilibrium catalyst and its impact on product distribution are studied. The analysis shows that a large amount of catalyst loss will lead to a large change in the particle size distribution of the equilibrium catalyst. The proportion of 0～40 μm catalyst, as well as 40～80 μm catalyst is greatly reduced, while the proportion of catalysts larger than 110 μm is greatly increased. The fluidization of the regenerator is unstable and the coke burning effect is getting worse. The temperature difference between the dilute phase and the dense phase of the regenerator is increased. The temperature fluctuation of riser outlet affected the thermal balance of the unit and cause the unit to run at reduced capacity. The catalyst micro-reactivity is greatly reduced, the reaction performance of the catalyst is also deteriorated, and the product distribution changed greatly.The yields of liquefied petroleum gas and gasoline reduce greatly, the yields of diesel and slurry increase significantly, and the yield of coke increased slightly.

Key words: catalytic cracking, catalyst loss, distribution of particle size, fluidization performance, micro-activity, product distribution