催化裂化装置烟机结垢问题的原因与防范措施

针对催化裂化装置各级旋风分离器工作异常以及催化剂磨损加剧造成烟气中催化剂微粒增加，导致烟机结垢的问题，结合3.5 Mt/a重油催化裂化装置等具体实例，对结垢原因进行了探讨。结果表明，各级旋风分离器排料不畅、负荷过高、三级旋风分离器单管负荷分布不均等问题会导致烟气中催化剂微粒增加，是造成三级旋风分离器和烟机结垢的重要因素之一。通过优化旋风分离器的设计，保证旋风分离器料腿排料顺畅，提高细粉回收率，可有效防止三级旋风分离器分离单管结垢堵塞，达到防止烟机结垢的目的。在对再生系统旋风分离器改造并加强相关工艺技术指标的监控后，烟机在最近三年运行状态良好。同时介绍了日常生产中的主要监控手段和控制指标。

CAUSES OF CATALYST DEPOSITS IN THE FLUE GAS EXPANDER OF RFCCU AND COUNTERMEASURES

The causes of catalyst deposits in flue gas expander of a 3.5 Mt/a RFCC unit were analyzed. It was found that with the increase of catalyst fines in flue gas, heavy deposition of catalyst in cyclone separation system and flue gas expander could be happened. In order to avoid increasing catalyst fines in flue gas, keeping the catalyst discharge of cyclones in good conditions, evading overloading and keeping balance loading of individual pipe for the third cyclone separator were essential. By optimizing the design of cyclone separator to smoothly discharge of catalyst and to increase the recovery rate of catalyst fines, the flue gas expander was kept running in good conditions for three years. Besides, some monitoring and control measures in daily operation were also introduced.