两套丙烷脱沥青装置工艺对比研究

A COMPARISON STUDY OF PROCESSES BETWEEN TWO PROPANE DEASPHALTING UNITS

针对中国石油克拉玛依石化公司两套丙烷脱沥青装置生产的目的产品脱沥青油性质和收率的差异,对两套丙烷脱沥青装置的生产工艺进行对比,并对产品进行试验和性质分析。结果表明,800 kt/a丙烷脱沥青装置生产的脱沥青油产品粘度小、收率高、粘度指数低的原因是其所含小于560 C馏分过多所致,是两套装置生产工艺有所差别而引起的。通过对两套丙烷脱沥青装置的抽提塔结构及抽提原理进行分析,提出了提高蒸馏装置减压深拔程度,以降低减压渣油中小于560℃馏分含量,提高抽提塔塔顶温度和降低溶剂比等相应的解决措施。

Due to the various properties and yields of deasphalted oil（DAO）produced by two propane deasphalting units（250 kt/a and 800 kt/a）of Karamay Petrochemical Company, a comparison study was carried out for analyzing the process conditions and products properties. It was found that containing excess〈560 ℃ components in the DAO of 800 kt/a unit was the main cause of its low viscosity,high yield and poor viscosity index,which was resulted from the differences in processes and operation conditions of the two units. By analyzing the structure of extractors and extraction process, countermeasures for improving the quality of DAO of 800 kt/a unit were proposed,such as enhancing the severity of vacuum distillation to reduce（560 ℃ components in vacuum residue feed,increasing the top temperature of extractor and reducing the solvent to oil ratio in extraction.