基于渣油结构表征的轻脱沥青油残炭超标原因分析

对溶剂脱沥青装置原料进行了窄馏分分离,并对窄馏分进行基本性质分析、质谱分析以及平均结构参数计算,研究了轻脱沥青油残炭值过高的主要原因。实验结果表明,随着窄馏分收率的增加,烷烃含量减少,芳烃含量增加,氢碳原子比逐渐降低,硫含量、氮含量、金属含量、相对分子质量和残炭值均呈现递增趋势。收率为21.6%~27.7%的窄馏分,它的残炭值大幅增加是导致轻脱沥青油残炭值过高,进而限制轻脱沥青油收率的主要原因;具有较多支链的低缩合芳烃含量的明显增加,是造成窄馏分残炭值过高的主要原因。

Cause analysis of the excessive carbon residue in light deasphalted oil based on structural characterization of residue

Narrow fractions were separated from raw materials of solvent deasphalting plant. The main reason for the excessive carbon residue in light deasphalted oil was analyzed through basic properties analysis,mass spectrographic analysis,and average structural parameter calculation of narrow fractions. The results show that alkane content decreased,and aromatic hydrocarbon content increases with the yield increasing of narrow fractions. The H/C ratio decreased gradually. The sulfur content,nitrogen content,metal content,relative molecular mass,and carbon residue content presented increasing tendency. Sharp increase of carbon residue of narrow fractions with the yield from 21.6% to 27.7% was the main reason for the excessive carbon residue and the yield limit of light deasphalted oil. The significant increase of low condensation aromatics with branched chains was the main reason for excessive carbon residue of the narrow fractions.