下行式中型装置中大庆常压渣油催化裂化初期的过程动力学——Ⅱ.试验结果的分析和讨论

DYNAMICS OF RESID CATALYTIC.CRACKING PROCESS IN THE PILOT PLANT WITH A DOWNFLOW TRANSFER REACTOR Ⅱ. ANALYSIS AND DISCUSSION OF PILOT PLANT RESULTS

采用液雾蒸发过程数值模拟软件对大庆常压渣油催化裂化的中型试验结果进行处理和分析。结果表明,专门的原料蒸发段对降低裂化过程的焦炭产率、改善裂化产品结构的作用是显著的。对中型试验结果的研究和分析表明,催化裂化过程初期动力学(Dynamic)因素(如原料的雾化和汽化程度、催化剂温度、催化剂与原料油的混合温度等)对渣油裂化过程有显著的影响。在较高的蒸发段汽化率和其它较优的操作条件下,可以得到优良的裂化产品结构。在中型试验研究的基础上,通过对原料油在催化剂微孔中的吸渗过程的流体动力学分析,提出了渣油催化裂化的物理化学模型,并对渣油催化裂化过程动力学因素的作用实质进行了分析。

A downflow transfer reactor system with special vaporization zone for studying dynamics of the initial period of resid catalytic cracking process was designed and set up. The main characteristics of this pilot plant are: a highly efficient atomization system for the feedstock, a controllable feeder system for hot catalyst, and the regenerator operation being independent of the reactor.With CRC-1 zeolite catalyst and Daqing reduced crude as feedstock, effects of some imp ortant variables in the initial period of resid catalytic cracking process were examined, including: atomization and vaporization of the feedstock, the temperature of inlet catalyst, the temperature of the mixing zone for the feedstock and catalyst, etc. The results showed that the said pilot plant is an useful tool for studying the dynamics of resid catalytic cracking.