基于Aspen Plus模拟的气体多级压缩过程(火用)分析

以某实际裂解气压缩过程为背景,建立了Aspen Plus流程模拟模型,分析了两种多变压缩过程模拟模型的特点及应用前提。根据热力学原理,对粗裂解气在绝热、等温以及多级压缩增设中间冷却等条件下的压缩过程进行了(火用)分析。结果表明:气体压缩过程中(火用)随压力的上升而增大,而在级间冷却过程中总(火用)则相应下降;压缩级数越多,压缩过程(火用)效率越高,但增幅逐渐平缓。五级压缩过程的实例研究结果表明,过程(火用)增加约2 350kW,过程(火用)效率为62.67%,回收热(火用)潜力为476kW。

EXERGY ANALYSIS OF MULTI-STAGE GAS COMPRESSION PROCESS BASED ON ASPEN PLUS SIMULATION

Different models for a polytropic compression process were analyzed by using Aspen Plus, with the multi-stage compression process of an actual cracking gas plant taken as background. According to the principle of thermodynamics, exergy analysis were conducted for the compression process of raw cracking gas under conditions of adiabatic, isothermal and multi-stage compression. The results showed that during the compression process, exergy increased as pressure increased, while the corresponding total exergy droped in the inter-stage cooling process. The compression exergy efficiency increased as the number of stages increased, and flattened gradually. The analysis for the practical five-stage compression process showed the exergy increase was 2 350 kW, and the exergy efficiency was 62.67%, potential for exergy recovery was 476 kW.