摘要
中国石化(SINOPEC)某乙烯装置处理量为640kt/a,主流程为前脱丙烷前加氢、双脱丙烷流程,制冷系统为三元混合制冷系统。该制冷系统在为分离系统提供冷量,满足一些低温精馏塔再沸器加热需求的同时,还通过冷剂的预冷及过冷,有效回收工艺物流的冷量。利用流程模拟软件及其他相关优化软件,建立该乙烯装置分离系统和制冷系统的工艺模型,并利用模型分析在当前工况下,脱乙烷塔进料分配量发生变化时,对该塔、冷箱及制冷系统的影响,根据本装置特点,进行脱乙烷塔和三元制冷系统的联合操作优化。将脱乙烷塔的三股进料量分别由45t/h、35t/h及70t/h调整为45t/h、45t/h及60t/h,同时适当降低三元冷剂缓冲罐VB-465的压力,以带走从脱乙烷塔进料物流侧额外回收的冷量,并将这部分冷量用于脱甲烷塔及乙烯精馏塔的冷剂用户。优化调整后,最终减少三元制冷压缩机功率消耗约1117kW,每年节省操作成本505万元,优化效果明显。
An ethylene unit of Sinopec has a processing capacity of 640kt/a.Its primary process is a front- end depropanization and front-end hydrogenation,double depropanization process and its refrigerating system is a ternary hybrid refrigerating system.While providing cooling to the separation system to meet some need for heating the reboiler of the low-temperature rectifying column,the refrigerating system also effectively recovers cooling quantity from process streams through precooling and supercooling of refrigerant.With the help of pro- cess simulaiton software and other optimization software,researchers established a process model for the sepa- ration system and refrigerating system of the ethylene unit and analyzed the effect of changes in the dis- tributed volume of feed in the dethanizer on the dethanizer,cold boxes and the refrigerating system with the help of the model under the current working conditions.Based on the analysis results and the characteristics of the unit,they conducted integrated operational optimization for the dethanizer and the ternary refrigerating system.The measures taken included changing the three charging rates of the dethanizer to 45t/h ,45t/h and 60t/h from 45t/h,35t/h and 70t/h while properly reducing the pressure of the ternary refrigerant buffer tank VB-465 in order to take away the additional cooling capacity recovered from the charging side of the detha- nizer and to supply the cooling capacity to the users of refrigerants of the demethanizer and ethylene rectify- ing column.After the optimization,the power consumption of the ternary refrigerating compressor dropped by around l117kW and annual savings of operational cost reachd 5.05 million RMB.
出处
《中外能源》
CAS
2013年第10期84-89,共6页
Sino-Global Energy
关键词
乙烯装置
脱乙烷塔
制冷系统
模拟
优化
ethylene unit
dethanizer
refrigerating system
simulation
optimization
