Conventional mud contains a lot of air, with an air content of 7% to 10%. The presence of the air prevents the wetting of solid particles and water, reduces the plasticity of the mud, increases the elastic deformation of the mud during molding, and causes the product defect. After vacuum mud scouring, the volume of mud air can be reduced to 0.5% to 1%, and due to the kneading and squeezing effect of the screw on the mud, the directional structure of the mud is improved and the components are more uniform. The shrinkage of the green body is reduced, the dry strength is doubled, and the product performance is significantly improved.