Gas Injection for Hydrodynamic Slug Control

Gas injection as an effective method to mitigate hydrodynamic slug has been studied using OLGA simulation. Different control strategies have been investigated to reduce the amount of injected gas required to mitigate slugs. The control strategies are based on using a PI controller to control the valve opening of gas injection through various riser measurements used as controlled variables. The results show that the holdup transmitter at the riser top as the controlled variable is the best control strategy, followed by the differential pressure across the riser. It is also concluded that using riser top choking reduces the requirement of injection gas.