天然气脱水系统模拟及主要设备优化

陕北某天然气净化厂由于新气源的并入,造成净化后商品气无法达到国家天然气相关标准,这是一个迫切需要解决的问题。通过ChemCAD 6.0.1软件对脱水系统进行模拟,研究分析TEG循环量、原料气进料温度及TEG贫液质量分数对脱水效果的影响,得到最佳的优化操作参数为:TEG循环量为5.5 m3/h,原料气进料温度为26℃,TEG贫液质量分数为99%。通过FRI,HTRI,Pipe Flow Expert等专业软件对TEG脱水塔、TEG贫液水冷器等关键设备进行核算,结果表明:TEG脱水塔的流体力学性能均符合要求,其工作点亦落在负荷性能图的适宜位置;TEG循环量提高导致TEG贫液水冷器负荷增大,需要更换管束,以达到换热效果。研究结果可为该净化装置的优化和改造提供可靠的理论依据,同时对同类型装置也具有一定的借鉴作用。

Simulation of natural gas dehydration system and optimization of main equipment

Due to the new gas sources incorporated into a natural gas purification plant in the north of Shaanxi province,the sales gas after purification can not meet the relevant national standard,and such problem needs to be solved urgently in the practical production.The dehydration system was simulated by ChemCAD 6.0.1 software and the influences of TEG(triethylene glycol) circulation quantity,the temperature of feed gas,lean TEG mass fraction on dehydration effect were analyzed.The best optimized operating parameters are as follows: the circulation quantity of TEG is 5.5 m3/h,the temperature of feed gas is 26 ℃,and the mass fraction of lean TEG is 99%.The key equipment such as TEG dehydration tower,lean TEG water cooler etc.were checked by FRI,HTRI,Pipe Flow Expert professional software.The results show that the hydrodynamic performance of TEG dehydration tower can meet the requirement;the operating point easily locates on the appropriate area of the load characteristic diagram.Because the increase of TEG circulation quantity causes heavier load,the original tubes need to be replaced so as to achieve a better effect for lean TEG water cooler.The results provide a reliable theoretical proof for dehydration system optimization and valuable reference for similar plants.