Design of three-phase separator under slug condition
The impact of slug flow change on equipment should be considered in the design of three-phase separator,and it can adapt to the whole cycle development process of oil-gas field.A transient model of multiphase flow of oil-gas-water is established by using OLGA software.Considering the influence of slug flow,the size of three-phase separator is calculated and the adaptability of three-phase separator to the change of flow parameters is simulated and analyzed.The results show that the average attenuation rate of the liquid plug length is 2.67 m/s,the residence time is 4 min,and the safety factor is 1.5.The final design size of the three-phase separator is 2 400 mm×7 200 mm,the nominal volume is 36 m3,and the number is 2.The maximum atmospheric oil ratio of the three-phase separator can be adapted to is 40 m3/m3,and the maximum liquid conveying flow rate is 700 m3/d.The change of pressure has almost no influence on the operation of the three-phase separator.