天然气乙烷回收关键参数分析研究

开展天然气乙烷回收可提高油气田的经济效益。以西北油田顺北区块天然气为案例，基于HYSYS软件建立乙烷回收模拟仿真模型，分别研究进深冷装置关键参数（进深冷装置压力、温度），关键设备参数（低温分离器温度、膨胀机出口压力、膨胀机效率、脱甲烷塔顶压力）和关键节点参数（干气回流比、低温分离器气相分流比）等对乙烷收率和装置能耗的影响规律，结果表明脱甲烷塔顶压力和低温分离器温度是乙烷回收最敏感的影响因素，因此在生产操作控制上应尽量保持脱甲烷塔顶压力和低温分离器温度为定值，减少其波动；另外，可通过改变干气回流比和低温分离器气相分流比来调节乙烷的收率和装置能耗。基于这些关键参数对乙烷收率和能耗的影响分析，为天然气乙烷回收的参数控制和参数调节提供了依据。

Analysis of the key parameters governing ethane recovery from natural gas

Ethane recovery from natural gas can improve the economic benefits of oil and gas fields. Taking the natural gas in the Shunbei block of the Northwest Oilfield as an example, an ethane recovery simulation model has been established based on HYSYS software. The effects of key parameters (pressure and temperature of the cryogenic unit), key equipment parameters (low temperature separator temperature, expander outlet pressure, expander efficiency, demethanizer top pressure) and key node parameters (dry gas reflux ratio and gas phase separation ratio of the low temperature separator) on the ethane yield and unit energy consumption have been studied. The results show that the top pressure of the demethanizer and the temperature of the cryogenic separator are the most important factors affecting the recovery of ethane. Therefore, fluctuations in the top pressure of the demethanizer and the temperature of the low-temperature separator should be kept as low as possible. In addition, the yield of ethane and the energy consumption of the unit can be controlled by adjusting the dry gas reflux ratio and the gas-phase split ratio of the low-temperature separator. The effects of these key parameters on the ethane yield and energy consumption have been analyzed, and the results provide a basis for parameter control and parameter adjustment during natural gas ethane recovery.