不同相态CO_2管内稳态节流实验

在CO_2管输过程中,节流易导致CO_2温降过大,威胁管道的安全运行。采用自主设计的CO_2节流实验装置,进行了不同相态CO_2管内稳态节流实验,采集管内参数变化情况,分别研究了节流前后压差、节流前CO_2相态及杂质N_2含量对CO_2稳态节流温降的影响。实验结果表明:CO_2的节流温降随节流前后压降的增大而增大,随N_2含量增大而减小;气态CO_2的节流效应最强,超临界态次之,液态CO_2节流效应最弱;节流前压力越大,相同压降的CO_2节流温降越小,节流前压力对气态CO_2节流温降的影响小于液态CO_2。

Experiment on steady-state throttling process of piped CO_2 at different phase states

In the process of CO2 pipeline transportation, throttling can lead to large CO2 temperature drop, and consequently threatens the safe operation of the pipeline. In this paper, the steady-state throttling experiment was conducted on CO2 of different phase states by using the independently designed CO2 throttling experiment device to acquire internal parameters inside the pipeline. And the influences of pressure difference before and after the throttling, CO2 phase state before the throttling and impurity N2 content on the CO2 temperature drop after steady-state throttling were investigated. It is indicated that CO2 temperature drop after the throttling increases with the increase of pressure difference before and after the throttling and decreases with the increase of N2 content. The throttling effect of CO2 is the strongest at gas state, secondly at supercritical state and the weakest at liquid state. As for the same pressure difference, the higher the pressure before the throttling, the smaller the CO2 temperature drop after the throttling. In addition, the CO2 temperature drop after the throttling is less affected by the pressure before the throttling at gas state than at liquid states.