Optimization & Modification In K Oilfield's NGL Recovery Unit

K Oilfield's NGL recovery unit based on the propane refrigeration cycle process is in Kazakhstan.Because of its serious aging phenomenon,the actual working condition meets a high deviation with its design and another issue is that NGL is at a low purchase price currently.Due to LPG's high demand and stable price in local market,reprocessing NGL to LPG and natural gasoline can get stable economic results.Therefore,making reasonable measures to build the LPG distilation system is quite necessary.By making investigation on recovery technologies of natural gas light hydrocarbon both at home and abroad,this paper shows the dilemma of this recovery process and two modification measures are proposed.Then numerical simulation is conducted by Aspen HYSYS and comparison is made through recovery rate,LPG and natural gasoline's production,exergy of the whole system,construction quantity and economic performance and a better modification measure is determined.Because this measure has a large improving space in many aspects,key operating parameters are optimized.After modification and parameters'optimization,the C₃ recovery rate could reach 90.92%,up4.13%than before and grows 26.41%compared with the original process;the C₃⁺recovery rate could reach 93.53%,rising 18.84%than the original process;the net profit could grow 160.1 thousand dollars per year than before.To test this unit's adaptability,the composition,boost pressure and temperature of feed gas have been designed and changed.By analyzing the tendency of C₃&C₃⁺recovery rate and unit product energy consumption,a conclusion can be drawn that this modified unit has strong adaptability.