Abstract: According to the lifting operation changes of the spent catalyst and interruption during back blowing in a CCR unit under low-load operation, after in-depth analysis of the reasons, it was found that when the pressure of the reaction system reduced, the separation hopper had no corresponding pressure-reducing mode. As a result, the opening of secondary gas control valve increased, and the “reverse pressure differential” of the spent catalyst flow increased from 15 kPa to 25 kPa, so that the flow of the spent catalyst in the riser was not smooth, and even interrupted after the back blowing. The problem could be solved by controlling the pressure of separation hopper and the opening of secondary gas control valve. Considering the feasibility and the difficulty of practical measures, using the manual pressure relief valve to reduce the separation hopper pressure, the “reverse pressure differential” of the spent catalyst flow was maintained at 15 kPa, opening the manual valve in time when back blowing to relieve pressure, which effectively solved the problem.

Key words: CCR unit, low-load, lift of spent catalyst, opening of secondary gas control valve, separation hopper pressure

摘要： 某企业连续重整装置在低负荷运行时待生催化剂(待生剂)提升操作发生变化,在反吹时甚至出现了提升中断的情况。深入分析原因发现,由于低负荷下反应系统压力下降,再生系统的分离料斗没有相应的降压方式,导致二次气控制阀开度增大、待生剂流动“逆压差”升高,由15 kPa升至25 kPa,从而使待生剂在立管内流动不畅,甚至在反吹后流动中断。从控制分离料斗压力和二次气控制阀开度的角度来解决问题。综合考虑措施的可行性和实际操作难度,使用分离料斗泄压手阀手动泄压来降低分离料斗压力,使待生剂流动“逆压差”维持在15 kPa,反吹时及时开大手阀泄压,有效地解决了问题。

关键词: 连续重整装置, 低负荷, 待生剂提升, 二次气控制阀开度, 分离料斗压力