催化烟机实际回收功率影响因素的探讨

Study on impact factors of actual recovered power of flue gas expander of FCCU

通过对催化裂化装置烟机实际回收功率问题进行探讨,全面分析主风总量、装置加工量、烟机入口压力、烟机出口压力、烟机入口温度、气温、双动滑阀开度、烟机结垢等如何影响烟机实际回收功率。分析得出：烟机入口压力控制在252～264kPa;烟机出口压力控制在5～8kPa;烟机入口温度控制在674～680℃;关闭或稍开双动滑阀;优化反再操作,控制烟气中催化剂细粉含量在较低水平,烟机入口烟气催化剂细粉密度小于200mg/m3;主风量调整过程要缓慢等结论使烟机实际回收功率保持在较高水平。同时提出多项维护烟机长周期高效运行的建议措施：严格控制烟机入口烟气温度小于680℃;烟机轮盘温度控制高限340～350℃,以防止催化剂细粉结垢严重;烟气管线加固保温以减少烟气输送过程中的热损失等,力保烟机高效长周期高效运行。

Through the study on the actual recovered power of flue gas expander in a FCC unit, the im pacts of total main air flowrate, FCCU operation capacity, inlet and outlet pressures of flue gas expander, inlet temperature of flue gas expander, atmospheric temperature, openness of doubleaction slide valve, operation time （operation time reflects the fouling of flue gas expander）, etc on the actual recovered power are ana lyzed. It is concluded that the actual recovered power can be kept at higher level when the inlet pressure range of flue gas expander is controlled at 252 264 kPa and the outlet pressure range is controlled at 5 8 kPa, the inlet temperature range of flue gas expander is controlled within the range of 674 ~ 680 ℃ , the doubleaction slide valve is closed or slightly open, the operation of reactionregeneration system is optimized, catalyst fines in flue gas are controlled at lower level, the density of catalysts is maintained at less than 200 mg/m3 and the main air flowrate is slowly adjusted, etc. In addition, a number of effective measures are recommended such as strictly controlling the temperature of inlet flue gas below 680 ℃, controlling the temperature of steam with in the range of 340 350℃ to prevent the fouling of steam turbine by catalyst fines and reinforcing heat insula tion of flue gas pipeline to reduce the heat loss in process of flue gas transmission. All these measures are taken to maintain the highefficiency longterm operation of flue gas expande