The Performance of Drag Reducing Agents in Multiphase Flow Conditions at High Pressure: Positive and Negative Effects

Drag reducing agents (DRA) in multiphase flow pipeline is of great interest in petroleum and pipeline industries since production can be increased by decreasing the pressure drop. Experiments were carried out in a 36-m long, 10-cm diameter multiphase flow system to examine the effect of drag reducing agents (DRA) on average pressure drop and slug characteristics. Superficial liquid velocities between 0.5 and 1.5 m/s and superficial gas velocities between 4 and 10 m/s were investigated. Temperature and pressure were maintained at 30 °C and 0.45 MPa. The DRA concentrations of 0, 25 and 50 ppm were used in this study. The results show that the average pressure drop decreased significantly by the change of flow characteristics when DRA was injected into the pipeline. At certain conditions, it was seen that a transition in flow pattern occurred from slug to wavy stratified flow with DRA. In addition, DRA was able to decrease the degree of turbulence at the gas-liquid interface with the addition of DRA. Some negative performance with the use of DRA in multiphase flow pipeline is also presented in this paper.