为提高乙烷回收流程的抗CO₂冻堵能力，基于RSV流程提出了一种抗冻堵能力强的富气乙烷回收工艺改进流程RSVP流程。针对3种高含CO₂且气质较富的天然气，对RSV流程和RSVP流程的总压缩功耗和CO₂冻堵裕量以及对CO₂适应性进行了对比分析。研究表明，RSV流程和RSVP流程的装置综合能耗基本相同，但RSVP流程的抗CO₂冻堵能力较强；不论原料气中CO₂摩尔分数如何变化，RSVP流程的CO₂冻堵裕量一直比RSV流程高，且对CO₂的适应性较强。对RSVP流程进行机理分析研究表明，相比脱甲烷塔顶不加重烃，加入重烃时脱甲烷塔CO₂冻堵裕量、乙烷回收率以及外输气丙烷摩尔分数均增高，脱甲烷塔上部CO₂摩尔分数下降，气相乙烷摩尔分数下降且气相甲烷摩尔分数升高，说明过冷的重烃进入脱甲烷塔顶具有吸收CO₂和冷凝乙烷组分的效果，但会导致重烃气化进入外输气中。最后对RSVP流程进行了特性分析，研究表明，预冷分离温度和液相分流比直接影响进入脱甲烷塔顶的重烃量，预冷分离温度保持在10~15℃且预冷分离器液相分流比保持在60%~80%时较为适宜。

In order to improve the ethane recovery process's anti ability against CO₂ freeze-plugging,RSVP,an improved process for recovering ethane from rich gas,is proposed on the basis of RSV process.As for three kinds of natural gas with high CO₂ content and rich temperament,the comparative analysis is performed for total compression power consumption and CO₂ freezing-plugging margin of RSV process and RSVP process,and the adaptability of CO₂.The research shows that RSVP process exhibits the same comprehensive energy consumption as that of RSV process,but RSVP has a stronger assistance to CO₂ freeze-blocking than RSV.No matter how the molar fraction of CO₂ in raw gas changes,RSVP always gives a higher CO₂ freeze-plugging margin than RSV,and shows a stronger adaptability to CO₂.The mechanism analysis shows that compared with the scene without addition of heavy hydrocarbons at the top of the methane removal tower,CO₂ freeze plugging margin,ethane recovery rate and the content of propane in export gas all increase when heavy hydrocarbons are added.In addition,CO₂ content at upper part of the methane removal tower also decreases,ethane content in gas phase decreases and methane content in gas phase increases,indicating that the overcooled heavy hydrocarbons entering the methane removal column has the effect of absorbing CO₂ and condensing ethane components,but will cause heavy hydrocarbon to enter the export gas.The results through analyzing the characteristics of RSVP process show that the pre-cooling separation temperature and liquid phase split ratio can directly affect the amount of heavy hydrocarbons entering the top of the methane removal tower.The pre-cooling separation temperature shall be maintained at 10-15℃ and the liquid phase split ratio in pre-cooling separator shall be kept in the range of 60%-80%.

蒋洪(1965-),男,硕士,教授,研究方向为油气集输及处理技术、系统能量综合利用及节能技术和汞污染控制技术