页岩气三甘醇脱水装置脱水效果影响因素分析

Analysis of Factors Affecting the Dehydration Effect of Shale Gas Triethylene Glycol Dehydration Unit

在页岩气田的不同生产阶段,各项工况参数变化范围较大,三甘醇脱水装置运行工况可能会偏离最佳区间,容易导致脱水效果不显著,从而影响正常生产。采用HYSYS软件,对300.0×10^(4)Nm^(3)/d的页岩气三甘醇脱水装置进行了流程模拟,定量分析了三甘醇循环量、三甘醇贫液质量分数、原料气入塔流量、原料气入塔温度、吸收塔操作压力、三甘醇贫液入塔温度、塔板总效率和吸收塔塔板数等工艺参数对三甘醇脱水效果的影响,并确定各项工艺参数的合理操作范围,以实现最佳脱水效果,满足干气外输要求。结果表明,提高三甘醇循环量、贫液质量分数、吸收塔操作压力、塔板总效率和吸收塔板数,以及降低原料气入塔流量和温度、三甘醇贫液入塔温度,有助于改善三甘醇脱水效果;提高重沸器温度和汽提气流量有利于提高三甘醇贫液质量分数。此外,将HYSYS模拟计算结果与现场生产数据进行了对比,结果表明两者基本吻合,从而验证了模拟计算结果的准确性,其可用于指导实际生产。上述研究结果对提高脱水效率和降低投资成本具有一定的指导意义。

In different production stages of shale gas fields,various operating conditions and parameters vary widely,and the operating conditions of the triethylene glycol dehydration unit may deviate from the optimal range,which may easily lead to insignificant dehydration effects,which will affect normal production.The HYSYS software was used to simulate the process of a 300.0×10^(4)Nm^(3)/d shale gas triethylene glycol dehydration unit.The influence of the process parameters on the dehydration effect of the triethylene glycol such as the triethylene glycol circulation volume,the mass fraction of the triethylene glycol lean liquid,the flow rate of the feed gas into the tower,and the temperature of the feed gas into the tower,the operating pressure of the absorption tower,the temperature of the lean triethylene glycol liquid entering the tower,the total efficiency of the trays and the number of trays in the absorption tower were quantitatively analyzed.And the reasonable operating range of each process parameter was determined to achieve the best dehydration effect and meet the requirements of dry gas export.The results show that increasing the triethylene glycol circulation,lean liquid mass fraction,absorption tower operating pressure,total tray efficiency and number of absorption trays,as well as reducing the flow and temperature of feed gas into the tower,and the temperature of triethylene glycol lean liquid entering the tower are all helpful to improve the dehydration effect of triethylene glycol;increasing the temperature of the reboiler and the flow of stripping gas are beneficial to increase the mass fraction of the lean triethylene glycol.In addition,the HYSYS simulation calculation results are compared with the on-site production data.The results show that the two are basically consistent,which verifies the accuracy of the simulation calculation results,which can be used to guide actual production.The above research has certain guiding significance for improving dehydration efficiency and reducing investment cost.