It was found that an unstable vortex zone existed in the upper space at the end of the riser of the super vortex quick separation (SVQS) system, which delayed the rapid draw-off of oil and gas and increased the risk of safe system operation. The velocity fields of SVQS system without vortex elimination plate, SVQS system with additional curved vortex elimination plate and SVQS system with new vortex elimination plate were analyzed, and it was found that the new vortex elimination plate improved the velocity field of the system, which in turn affected the separation performance of the system. The new vortex elimination plate reduced the pressure drop and the energy loss of the system without reducing the separation efficiency of the SVQS system. The concept of oil and gas residence time was introduced to analyze the specific residence time of oil and gas in the SVQS system, and it was found that the vortex elimination plate could reduce the residence time of oil and gas and fine particles in the system, and the residence time of oil and gas in the SVQS system with the addition of the new vortex elimination plate was smaller than that in the SVQS system with the addition of the curved vortex elimination plate. A comprehensive comparison revealed that the structure and performance of the new vortex elimination plate was superior and more informative for industrial applications.