RSV乙烷回收控制CO2冻堵工艺改进

RSV ethane recovery process improved to avoid CO2 freezing

为提高RSV流程对原料气CO2摩尔分数的适应性,应用重烃对CO2的吸收原理提出部分原料气过冷乙烷回收工艺(recycle split-vapor and feed,RSVF),并对提出的RSVF流程进行了改进效果、原料气CO2适应性及流程特性分析。分析结果表明,与RSV流程相比,RSVF流程对原料气CO2摩尔分数适应性更强,相同条件下提高CO2冻堵裕量1.5~1.8℃,节省主体装置总压缩功0~7.56%;当原料气CO2摩尔分数达2.5%时,对不同气质RSVF流程仍能达到90%以上的乙烷回收率。此外,RSVF流程过冷原料气的量一般控制在原料气总量的10%~20%;低温分离器气相过冷量控制在低温分离器气相总量的1%~10%;低温分离器液相过冷量需根据气质条件及原料气CO2摩尔分数确定。

In order to improve the adaptability of RSV process to CO2 content in feed gas,a ethane recovery process with feed gas partly supercooled( Recycle Split-Vapor and Feed,RSVF) is proposed based on the principle of heavy hydrocarbons to absorb CO2. The RSVF process is improved,and the adaptability to CO2 in feed gas and the process characteristics are analyzed. The analysis results show that compared with RSV process,the RSVF process is more adaptable to the content of CO2 in feed gas. Under the same conditions,CO2 freeze plug margin is increased by 1. 5-1. 8℃,saving the total compression work of the main device by 0-7. 56%.Ethane recovery rate by RSVF process can still exceed 90% under different feed gases when the content of CO2 in feed gas reaches 2. 5%. In addition,the amount of supercooled feed gas in the RSVF process is generally controlled at 10% to 20% of the total amount of the feed gas;the gas phase supercooling amount is controlled at 1% to 10% of the total gas phase in low temperature separator;the liquid phase supercooling amount in low temperature separator shall be determined according to the temperament conditions and the CO2 content in the feed gas.