延迟焦化分馏塔喷淋脱过热与循环比的拟合计算

Fitting Calculation of the Recycle Ratio and the Spraying Intensity of De-superheating Gas Oil in DCU Fractionating Column

通过PROⅡ软件模拟计算,对某炼厂延迟焦化装置进行了核算改造,将装置循环比从原0.6降低至0.2,大大提高了装置的总液收率和经济效益。在分馏塔脱过热段采用蜡油喷淋替代原焦化原料上进料与焦化油气换热的脱过热方式,大大提高了气液传质效率及对焦化油气中焦粉的洗涤效果,提高了焦化蜡油的指标,减少了原人字板的结焦及焦化液体产品中焦粉的夹带量。着重介绍了降低循环比后主分馏塔的工艺调整计算及脱过热段蜡油喷淋量与循环比的拟合计算过程,并简述了脱过热段的改造工程方案。

Based on the simulation by PROⅡ,the recycle ratio of DCU in a North China refinery was reduced from 0.6 to 0.2,which rapidly increased the liquid product yield and the overall economic benefits of the unit.In the de-superheating section of the main fractionator,the trays were replaced by sprinklers and the wax oil was sprayed as the quench oil instead of the heavy residue oil,which greatly improved the gas-liquid mass transfer efficiency and the washing effect of coke powder in the reaction gas,reduced the coke powder in the liquid products and the risk of coking in this section.In this paper,the process adjustment calculation of the main fractionator and how to match the sprayed gas oil and the recycle ratio were introduced emphatically.The engineering modification of the main fractionator was also mentioned briefly.