吸收稳定系统稳定塔侧线汽油作补充吸收剂

STUDY ON USING STABILIZER SIDE-CUT NAPHTHA AS SUPPLEMENTARY ABSORBENT OF ABSORBER

改善吸收塔中C_3及以上组分的吸收效果,减少贫气中的丙烯含量,实现干气变"干",是提高催化裂化装置吸收稳定系统丙烯回收率的关键。从改善吸收塔补充吸收剂的物性人手,研究了用稳定塔侧线汽油作吸收塔补充吸收剂的效果。与稳定汽油相比,稳定塔侧线汽油的分子极性更接近丙烯的分子极性,因此可大大提高吸收塔的吸收效果。研究结果表明,采用此新工艺后,干气中丙烯的摩尔分数可降低31.5%,干气量可下降1.7%,一套1.0 ML/a的催化裂化装置可因此增加丙烯产量915.6t/a;同时,装置的汽油产量和质量保持不变,吸收稳定系统的能耗基本不增加。

The improvement of absorption performance of C3＇s and plus in absorber and reduction of pro- pylene in lean gas are critical to increase propylene＇ s recovery rate of absorption-stabilization system of FCCU or RFCCU. The performance of side-cut naphtha of stabilizer as supplementary absorbent is studied on the basis of improving physical properties of supplementary absorbent. As compared with stabilized naphtha, the molecule polarity of stabilizer side-cut naphtha is closer to that of propylene. The study shows that, with the new process, the propylene in dry gas can be reduced by 31.5% and the yield of dry gas is lowered by 1.7%. An annual 915.6 tons of additional propylene will be produced in a RFCC unit with a capacity of 20 000 b/d, while the quality and quantity of product naphtha remain unchanged and there is no increase in the energy consumption of the absorption-stabilization system.