Enhancing the Supersonic Gas Separation operating envelope through process control strategies of the feed conditioning plant for offshore CO2 removal from natural gas

•One of the potential technologies for offshore CO2 capture is Supersonic Gas Separation (SGS).•Robust feed conditioning process plant is required due to stringent requirements of cryogenic temperature, pressure and inlet CO2 composition.•Control strategies for the SGS feed under ±15% disturbances in temperature, pressure and ±5 mole% variations in CO2 are studied.•Effective disturbances elimination in the first flash separator of the SGS feed plant is crucial in minimizing the impact to the SGS operation.•PID controller performs significantly better in disturbance rejection than Model Predictive Control.