摘要
目的国内油田伴生气乙烷回收均采用液相过冷工艺(LSP),解决该工艺在乙烷回收运行工况中存在的能耗较高、回收率较低的问题。方法基于LSP工艺流程和气相过冷、气液相混合过冷的原理,提出气液两相过冷改进工艺(GLSP)、原料气分流过冷工艺(FGSP),并进行工艺流程对比分析,重点研究改进工艺的特性和对原料气中CO_(2)的适应性。结果①GLSP工艺适用于外输气压力低的油田伴生气乙烷回收,具有乙烷回收率高、CO_(2)适应性强(CO_(2)摩尔分数为0.5%~2.5%)等特点;②GLSP工艺流程最优增压压力范围为4.0~4.5 MPa,乙烷回收率不宜超过95%;③在原料气中CO_(2)含量相同的条件下,随着气质变富,脱甲烷塔控制CO_(2)冻堵的能力不断增强;④在同一气质条件下,装置总能耗随着原料气中CO_(2)含量的增加而增大。结论提出的改进工艺提高了乙烷回收率,确定了最优增压范围,并提高了对原料气中CO_(2)的适应性,为实际低压富气乙烷回收装置设计提供参考。
Objective The domestic oilfield-associated gas ethane recovery adopts liquid subcooled process(LSP);the aim of this study is to solve the problems of higher energy consumption and lower recovery rate in the actual operation condition of LSP.Methods Based on the LSP and the principles of gas-phase subcooling and gas-liquid two phases mixed subcooling,two improved processes,gas and liquid subcooled process(GLSP)and feed gas split subcooled process(FGSP),were proposed and analyzed in comparison with each other,focusing on the characteristics and adaptability to CO_(2) in the raw gas.Results Firstly,the GLSP is suitable for the ethane recovery process of oilfield-associated gas with low outgoing gas pressure.It is characterized by high ethane recovery rate and strong adaptability to CO_(2)(CO_(2) mole fraction of 0.5%-2.5%).Secondly,the optimal pressurization pressure range of the GLSP is 4.0-4.5 MPa,and the ethane recovery rate should not exceed 95%.Thirdly,under the same condition of the CO_(2) content of raw gas,as the gas becomes richer,the ability of the demethanization tower to control CO_(2) freezing and blocking is increasing.Fourthly,under the same gas conditions,the total energy consumption of the plant increases with the increase of CO_(2) content in the feed gas.Conclusions The proposed improved process has increased the recovery rate of ethane,determined the optimal pressurization range,and improved the adaptability to CO_(2) in the raw gas,providing a reference for the design of actual low-pressure rich gas ethane recovery devices.
作者
雷利
刘清松
陈泳村
蒋洪
LEI Li;LIU Qingsong;CHEN Yongcun;JIANG Hong(Central Sichuan Oil and Gas District,PetroChina Southwest Oil&Gasfield Company,Suining,Sichuan,China;School of Petroleum and Gas Engineering,Southwest Petroleum University,Chengdu,Sichuan,China)
出处
《石油与天然气化工》
CAS
CSCD
北大核心
2024年第3期43-48,共6页
Chemical engineering of oil & gas
关键词
低压富气
乙烷回收
回收率
工艺改进
CO_(2)冻堵
low pressure rich gas
ethane recovery
recovery rate
process improvement
CO_(2)freezing and blocking
