对二甲苯吸附分离工艺模型建立与冲洗方式的优化计算

石油炼制与化工 ›› 2021, Vol. 52 ›› Issue (9): 83-89.

对二甲苯吸附分离工艺模型建立与冲洗方式的优化计算

朱宁,李林玥,杨彦强,王德华

中国石化石油化工科学研究院

收稿日期:2020-11-30 修回日期:2021-04-09 出版日期:2021-09-12 发布日期:2021-08-30
通讯作者: 朱宁 E-mail:zhuning.ripp@sinopec.com
基金资助:
中国石油化工股份公司项目

MODELING AND OPTIMIZATION IN BED-LINE FLUSHING METHOD OF THE PARA-XYLENE SEPARATION SYSTEM

Received:2020-11-30 Revised:2021-04-09 Online:2021-09-12 Published:2021-08-30

摘要/Abstract

摘要： 为了优化对二甲苯（PX）吸附分离工艺的冲洗方式，采用静态吸附法研究了在吸附温度为180 ℃、吸附压力为0.8 MPa条件下不同浓度的C₈芳烃异构体在PX吸附剂上的饱和吸附量和吸附平衡常数，并采用动态穿透曲线法进行数据拟合，得到各个组分在吸附剂上的传质系数；以所得参数为基础，建立了PX吸附分离工艺计算模型，考察床层管线死体积、冲洗流量、冲洗液组成等变量对吸附剂的吸附分离性能的影响，计算出较优的冲洗配置为：解吸剂进料和抽出液出料之间的管线用解吸剂冲洗，抽出液出料和原料进料之间的管线用抽出液冲洗，原料进料和抽余液出料之间的管线用原料冲洗。

关键词: 模拟移动床, 模型, 吸附分离, 二甲苯分离

Abstract: The saturated adsorption capacities and equilibrium constants of C₈ aromatic isomers were obtained by the static adsorption method. The breakthrough curves of C₈ aromatics isomer were plotted by dynamic adsorption experiments. The lumped mass transfer coefficients of C₈ aromatics were calculated through curve fitting by Aspen Chromatography. Based on the parameters above, the model of the industrial-scale simulated moving bed for para-xylene separation was constructed. The influences of dead volume, flushing flow rate and flushing liquid composition on the adsorption and separation performance of adsorbent were investigated. Especially, the optimization calculation of the bed-line flushing method was carried out and the preferable flushing set was figured out. The optimized the flushing method was calculated where the desorbent was used as the flushing stream between desorbent and extract ports, the extract stream was used between extract and feed ports, and the feed stream was used between feed and raffinate ports.

Key words: simulated moving bed, model, adsorption separation, xylene separation

朱宁李林玥杨彦强王德华. 对二甲苯吸附分离工艺模型建立与冲洗方式的优化计算[J]. 石油炼制与化工, 2021, 52(9): 83-89.

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