Sand and gravel separator is a sand and gravel separation equipment suitable for rivers, reservoirs, and coal yards. Composed of the hull, frame, gearbox, conveyor belt, rotary screen, engine or motor. This model has a simple structure, is economically applicable, and easy to operate. It is divided into drum type sand screening machine, washing drum type sand screening machine, vibrating screen type sand screening machine, etc. Separators are widely used in industries such as highways, hydropower, and construction for washing, grading, and impurity removal, as well as for washing fine-grained and coarse-grained materials. They are suitable for building and road construction sand and gravel, and can clean and separate soil and debris from sand and gravel. Their novel sealing structure, adjustable overflow weir plate, and excellent transmission device have good cleaning and dehydration effects. Used for the recycling of residual concrete generated during the production and transportation process of large and medium-sized concrete mixing plants, the aggregate and mud water are separated by washing and spiral method. The sand and stones of the aggregate are washed and discharged into the sand pool and stone pool respectively, which can be reused. The mud water can be reused in production after sedimentation and filtration, and the sewage can be used for car washing after sedimentation and filtration. The mud water can be used in the production of the mixing plant, which not only saves water, but also improves the strength of the concrete under the same conditions, achieving less waste discharge.