催化裂化分馏和吸收稳定全流程模拟与优化

Process simulation and optimization for fluid catalytic cracking fractionation system and absorption-stabilization system

关键词:  Aspen-Plus  全流程模拟  恩氏蒸馏曲线  补充吸收剂  分馏塔 

Key words:  Aspen-Plus  whole process simulation  ASTM D86 curve  additional absorbent  fractionating tower

摘要:

应用Aspen-Plus流程模拟软件,对金陵石化Ⅰ催化裂化分馏和吸收稳定系统进行全流程模拟,产品的恩氏蒸馏曲线基本与实际相符。分析得出,随着分馏塔顶循、一中返塔温度的上升,汽油干点和柴油的95%馏出温度均上升,此外,在保证稳定塔塔底再沸器热负荷和分馏塔产品质量合格的前提下,模拟求得一中最小循环量和相应的油浆占总取热量的最大比例；其次,随着补充吸收剂流量的增大,干气中C⁺₃的体积分数逐渐降低,解吸塔和稳定塔再沸器的热负荷逐渐增大；随着解吸塔再沸器热负荷的增加,液态烃中C₂体积分数逐渐下降,稳定塔再沸器的热负荷也随之增大。由此可知,为了保证产品质量,需调节分馏塔各相应段的取热量,并调节好吸收稳定系统的再沸器热负荷、液气比等操作参数。整个模拟与优化过程对生产具有积极的指导意义。 

Abstract:

The Aspen-Plus process simulation software was applied to simulate the whole process of fractionation, absorption and stabilization system of Jinling Petrochemical Company 1# FCC. The simulated ASTM D86 curve of the products agreed very well with the actual curves. The results showed that the gasoline endpoint and the 95% distillate temperature of diesel oil increased with the rise of top cycle and the first middle return temperature. In addition, under the premise of ensuring the heat load of stable column bottom reboiler and the quality of the distillation column products, the minimum circulating flow rate of the first middle and the maximum ratio of the slurry to the total amount of heat were obtained by simulation. With the increase of absorbent flow, the volume fraction of C⁺₃ in dry gas reduced gradually, the heat duty of the desorption tower and the reboiler of stable tower increased gradually. With the heat duty increase of desorption tower reboiler, the volume percentage of C₂ in LPG decreased gradually, and the heat duty of the stable tower reboiler increased. In order to ensure the quality of the products, it needs to adjust the heat remove of different fractionating tower sections. In addition, it is important to adjust the reboiler heat load, liquid gas ratio and other operating parameters of the absorption stabilization system. The simulation and optimization provide positive guiding significance to the production.