富含CO2天然气低温分离防冻堵工艺研究

富含CO2天然气在采用低温分离技术进行处理时,容易导致天然气处理装置发生CO2冻堵,造成装置停车甚至设备损坏,影响装置的正常生产。借助HYSYS模拟软件,选择P-R状态方程,通过气体过冷、液体过冷、残余气再循环、残余气富集再循环、加入防冻剂五种工艺的CO2在脱甲烷塔塔液分布、乙烷收率、能耗等方面的对比分析,寻求较佳的方案解决富含CO2天然气轻烃回收装置的冻堵问题。经过综合分析得出,残余气再循环工艺及残余气富集再循环工艺性能优良,能有效处理富含CO2天然气。

Study on Technology for Preventing Ice Plug in Low Temperature Separation of Natural Gas Containing Rich CO2

If low temperature separation technology is applied for treating rich CO2 gas,ice plugging will occur often in gas treatment unit,which will result in shutdown and equipment damage and affect normal production.With the help of Hysys simulation software,selected is the P-R state equation and analyzed are CO2 fluid distribution in demethanizer,ethane recovery and energy consumption in such five processes as liquid supercooling process,gas supercooling process,residual gas recycling process,residual gas enrichment recycling process and antifreezing agent injection,explored is a better process plan to solve ice plugging in light hydrocarbon recovery unit for natural gas containing rich CO2.Comprehensive analysis results show that residual gas recycling process and residual gas enrichment recycling process have excellent performance and can effectively treat rich CO2 gas.