Abstract:

The efficient utilization of refinery naphtha has an important impact on the economic benefit of the integrated refinery and chemical enterprises. The problems existing in the production process of CDU naphtha, hydrogenation naphtha, light and heavy naphtha of hydrocracking unit in a refinery were analyzed. The optimization measures were put forward according to the molecular management concept of “making ethylene if it is suitable for ethylene, making aromatics if it is suitable for aromatics, making oil if it is suitable for oil”. Changes in the blending ratio of crude oil result in a decrease in the mass fraction of paraffin in CDU naphtha. It is suggested to optimize the quality and yield of naphtha by “planning in advance” and “dynamic adjustment”. The final boiling point of hydrogenated naphtha increased from 190 ℃ to 230～240 ℃, the yield increased from 22% to 30%～40%, the mass fraction of paraffin decreased from 70% to 60%～65%, and it was still a relatively high quality cracking feedstock. Mass fraction of chain paraffin in the crude naphtha in the stripper of the hydrogenation unit reached 74.17%, so it was turned to the light hydrocarbon system of the atmospheric and vacuum distillation unit. Thus, CDU naphtha yield increased by 0.5 percentage points, and the high quality ethylene feedstock was increased effectively. The model of oil and gas pipeline at the top of the hydrocracking stripper was established by HYSYS. The optimal target of temperature at the top of the tower was determined through calculation, and the temperature was controlled at no less than 95 ℃ in summer and 98 ℃ in winter, respectively.

Key words: refining and chemical enterprise, refining naphtha, catalytic cracking diesel, group composition, final boiling point, paraffin

摘要：

炼油石脑油的高效利用对炼化一体化企业的经济效益有重要影响。分析了某炼化企业蒸馏石脑油、加氢石脑油和加氢裂化轻、重石脑油生产过程中存在的问题，按照“宜烯则烯，宜芳则芳，宜油则油”的分子管理理念提出了优化措施。原油掺炼比例变化导致蒸馏石脑油链烷烃质量分数下降，建议通过“提前筹划”“动态调整”实现石脑油质量和产量最优化。加氢石脑油终馏点由190℃提至230～240℃,收率由22%上升至30%～40%,链烷烃质量分数由70%降至60%～65%,仍是较优质的裂解原料。催焦柴加氢装置汽提塔粗石脑油链烷烃质量分数达到74.17%,将其改至常减压蒸馏装置轻烃系统，蒸馏石脑油收率提高0.5百分点，有效增产了优质乙烯原料。利用HYSYS软件建立加氢裂化汽提塔顶油气管道模型，通过核算确定塔顶温度优化目标，夏季和冬季控制温度分别不低于95、98℃。

关键词: 炼化企业, 炼油石脑油, 催化裂化柴油, 族组成, 终馏点, 链烷烃