The equipment relies on the physical principle of centrifugal sedimentation to complete the separation of starch milk and sand impurities by using density difference. Slurry enters the cylinder from the eccentric tangential direction to form a high-speed rotating flow field, and sand impurities are thrown to the wall and sink. The purified starch milk moves to the center, forms upward overflow and is discharged from the top outlet to enter the subsequent section. The sinking sand impurities gather in the cone bottom slag hopper. The internal structure of the equipment can prevent impurity backmixing and ensure separation effect. The equipment realizes swirling separation only by feeding pressure without mechanical transmission, running smoothly and energy-saving. Operators can complete impurity cleaning by regularly opening the slag discharge valve to ensure continuous operation of the equipment.