The drum of the rotary dryer is a slightly inclined and rotatable cylindrical body, with wet materials entering from the upper part of one end and dry materials collected from the lower part of the other end. Hot air enters from the feeding or discharging end and is discharged from the upper part of the other end.
The cylinder is equipped with a forward copying plate, which continuously picks up and sprinkles the material during the rotation of the cylinder, allowing it to fully contact with the hot air flow to improve drying efficiency and move the material forward.
The heat source for drying materials is generally hot air, high-temperature flue gas, water vapor, etc. Specific selection can be made based on the properties and quality requirements of the material.

Quartz sand is transported to the hopper by a belt conveyor or bucket elevator, and then enters the feeding end through the feeding pipeline through the feeding machine of the hopper. The slope of the feeding pipeline should be greater than the natural inclination angle of the material, so that the material can flow smoothly into the dryer. The dryer cylinder is a rotating cylinder slightly inclined from the horizontal line. The material is added from the higher end, and the heat carrier enters from the lower end, coming into counter current contact with the material. There are also cases where the heat carrier and the material flow together into the cylinder. As the cylinder rotates, the material moves to the lower end under the action of gravity. During the forward movement of the wet material inside the cylinder, it directly or indirectly receives heat from the heat carrier, allowing the wet material to dry, and then is sent out through a belt conveyor or screw conveyor at the discharge end. There is a copying plate installed on the inner wall of the cylinder, which is used to pick up and sprinkle the material, increase the contact surface between the material and the airflow, improve the drying rate, and promote the advancement of the material. Thermal carriers are generally divided into hot air, flue gas, etc. After passing through the dryer, the heat carrier generally needs a cyclone dust collector to capture the materials carried in the gas. If further reduction of exhaust dust content is required, it should be discharged after passing through a bag filter or wet dust collector.