Abstract: As the core component of the vacuum interface valve that separates the atmosphere and vacuum in the vacuum sewage system on ships, the design of a reliable and practical vacuum interface valve is crucial to the whole vacuum sewage system. In this paper, a vacuum interface valve is designed, using ANSYS Workbench to carry out finite element analysis on the rubber spool on the rubber spool, to explore the shape variable and stress law under different pressure and spool structure, and to simulate the passability by utilizing the DPM particle model to detect the percentage of exported particles, and to conclude that the optimal ratio of the interface valve's design parameter is 1.40:1, and that the exported particles show a normal distribution phenomenon. Combined with the particle trajectory cloud map and velocity cloud map, we analyze that the reason for the normal distribution of the exit particles is that particles with different diameters have different mass velocities, and the particles are subject to different gravitational forces as well as different Saffman's shear lifting forces, which explains the reason for the distribution of the exit particles. Due to the different shape variables caused by the spool structure, the distance of the particles from the wall surface is different, so the wall surface of different structural models absorbs particles to a different extent, which makes the percentage of exported particles different, and this analysis explains the differences in the passage of the valve caused by the different structures of the vacuum interface valve.