汽提条件对两段提升管催化裂化待生剂汽提过程的影响

Influence of Stripping Conditions on Stripping of Spent Catalysts From Two-Stage Riser Fluid Catalytic Cracking Unit

在模拟汽提实验装置上,对两段提升管催化裂化工业装置不同提升管内的待生剂进行了汽提实验研究。结果表明,汽提温度和汽提蒸汽流量均存在最佳值。当汽提温度为510℃时,两种待生剂的汽提效率达到最大值。继续提高汽提温度,一段待生剂汽提的产物分布和焦炭组成无明显变化;而二段待生剂的焦炭产率略有增加,且焦炭由可溶性焦炭向不可溶焦炭转变。汽提蒸汽的流量对两种待生剂汽提过程的影响趋势相似,但是二段待生剂达到最大汽提效率所需的蒸汽流量高于一段待生剂。汽提后待生剂的可溶性焦炭分析表明,二段待生剂可溶性焦炭的缩合度高于一段待生剂,且二段待生剂表面和孔道内沉积的可溶性焦炭的组成差别较小。

Experimental stripping of spent catalysts from different risers of a commercial TSRFCC unit was carried out in laboratory.The results show that the stripping temperature and steam flow can be further optimized.Stripping efficiency of two spent catalysts reaches the maximum value at 510℃.The stripping product distribution and stripped coke content of spent catalyst from 1 st stage riser doesn't change obviously when the temperature is being raised sequentially.However,the stripped coke yield of spent catalyst from 2 nd stage riser becomes increased slightly,and more soluble coke is converted to insoluble coke.Steam flow has similar effect on stripping of both spent catalysts.Nonetheless,the spent catalyst from 2 nd riser need more steam flow to get much higher stripping efficiency than the spent catalyst from 1 st riser.Composition of soluble coke from stripped spent catalyst shows that the condensation degree of 2 nd riser soluble coke is higher than that of 1 st riser soluble coke.And there is no obvious difference between the soluble coke on surface and the soluble coke in pore of the stripped spent catalyst from 2 nd riser.