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.