委内瑞拉奥里超稠油减黏工艺研究

Visbreaking of Venezuela Orinoco super heavy oil

进行了不同反应温度和反应时间的减黏裂化反应,确定了高温短时间和低温长时间2种反应的较佳反应条件,分别为:415℃/30min,390℃/2h。并考察了反应的生焦率及产物的黏度、收率、四组分含量、残炭、凝点、闪点及胶质和沥青质结构。结果表明,委内瑞拉奥里超稠油可以采用减黏裂化工艺进行降黏,并使产物满足380#燃料油黏度标准。减黏反应的温度和时间是互补的,减黏反应进行的深度是反应温度和反应时间共同作用的结果。较高的反应苛刻度使得减黏产物成为非牛顿流体,呈现假塑性流体形态,且有屈服值,对船运可能造成一定的影响。因此,减黏反应的条件要严格控制。高温反应产物的胶质和沥青质的缩合程度较高,同时结构单元中的芳环数也较多,进一步生成生焦前驱物的趋势较强。最终确定委内瑞拉奥里常渣减黏裂化的最佳反应条件为:390℃/2h。

415℃/30 min and 390℃/2 h are respectively decided as the optimal reaction conditions at high temperature for brief periods and the low temperature for long periods.Coking yield,viscosity,liquid product yield,SARA,carbon residue,freezing point,flash point and the structures of resin and asphaltene are studied.The results show that the viscosity of Venezuela Orinoco AR may be decreased by visbreaking reaction,and meet the viscosity standard of 380# fuel oil.The reaction temperature and time are complementary,and jointly effect reaction depth of visbreaking.Visbroken product becomes non-newtonian fluid at relatively high reaction conditions,presents the property of pseudoplastic fluid and has yield value,which influences ship transportation.So the reaction conditions must be strictly controlled.Condensation degree of resin and asphaltene of visbroken product at 415℃/30 min is higher than that of 390℃/2 h,and the aromatic ring number in structural unit increases.Visbroken product at high temperature for brief periods has more strong trend to formation coke precursor.Finally,390℃/2 h is considered as better reaction condition.