采用Aspen Plus软件对轻烃回收装置优化设计

Optimized design of light ends recovery unit with Aspen Plus process simulation software

采用Aspen Plus软件对新建的一套2.8 Mt/a轻烃回收装置吸收塔-再吸收塔-脱吸塔-稳定塔的四塔流程进行模拟,并使用灵敏度分析对轻烃回收系统的主要影响因素（包括吸收剂的选择、再吸收塔设置、脱吸塔的进料方式以及稳定塔回流比等）进行了研究,结果表明：1选用常压塔顶一级冷凝石脑油和稳定塔底石脑油分别用作吸收剂和补充吸收剂时的液气质量比为4.18,C3,C4组分的吸收率达到95%以上,干气质量好;2增设再吸收塔且再吸收塔采用16块浮阀塔盘后,干气中C＋3组分的摩尔分数由2.3%降为1.4%,预计可回收液化石油气产品535 t/a,可增加经济效益267万元/a;3脱吸塔进料方式采用冷、热双股进料,选择第25块板为最佳进料位置;4稳定塔适宜的回流比为3.6-3.8。

The 4-tower （absorber, re-absorber, desorption, debutanizer） process of a new 2.8 MM TPY light ends recovery unit is simulated with Aspen Plus software. The main impact factors of light ends recovery system （including absorbent selection, design of re-absorber, feeding of desorption and reflux ratio of debu-tanizer, etc） are studied. The results show that ： 1 ） When the 1 st-sidedraw condensate naphtha from the overhead of atmospheric column and the stabilized naphtha from the bottom of debutanizer are used as absorbent and supplementary absorbent and the liquid to gas ratio is 4.18, the absorption rate is over 95 % and dry gas quality is good; 2） When a new absorber is added and installed with 16 floating valve trays, the mole fraction of C3^＋ in dry gas is reduced to 1.40/o from 2.3%. The expected LPG recovery is 535 t/a, and annual economic benefit is 2.67 million Yuan RMB ; 3 ） Both hot and cold feeds are fed into the de-absorber at 25th tray ; 4） The proper reflux ratio of debutanizer is 3.6 - 3.8.