Sludge enters the guide plate in the dryer from the feeder through the chute. With the rotation of the cylinder, the sludge is guided to the inclined lifting plate, which is lifted to the center of the cylinder and gradually descends to form a curtain. The high-temperature airflow passes through the curtain to preheat the sludge and evaporate some water. When the sludge overflows and moves to the movable grate wing, the material is mixed with the preheated grate wing to transfer heat to the material, so that part of the water evaporates. At the same time, the material entrained by the wing plate is lifted and sprayed for many times, and the material and the hot air flow carry out convection and contact heat exchange. At the same time, the cleaning device buried in the material also slides down along the inner side of the arc-shaped lifting plate to clean the material attached to the inner wall of the lifting plate. After rotating the vertical line with the cylinder, the cleaning device is dragged on the back of the arc lifting plate to clean the materials attached to the outer wall of the lifting plate. With the continuous rotation of the drum, part of the water evaporates and the sludge is further dried. At the same time, the cleaning device also plays a role in crushing sludge particles and improving the drying speed. Finally, after drying, the sludge becomes loose material with low moisture content and is discharged from the discharge port.
The most commonly used sludge drying equipment is a single-channel rotary dryer;
Suitable for drying municipal sludge. Single-channel rotary dryer is a new type of equipment developed on the basis of ordinary rotary dryer. It is equipped with depolymerization mechanism, movable grate wing, cleaning device and crushing device, which can dry sticky materials that ordinary rotary dryers can't handle. According to the characteristics of sludge with certain viscosity and small particle size, single channel dryer is the best choice. Single-channel rotary dryer, downstream process and specially designed feeding device are used to exchange heat with high-temperature hot flue gas at the moment when sludge enters the dryer, and a hard shell is formed on its surface, which greatly reduces the phenomenon of sludge sticking to the cylinder and blocking by accumulated materials. In addition to the lifting plate, the dryer head 1/4 section is also equipped with a depolymerization mechanism to enhance evaporation and a linked grate wing plate, which can not only conduct heat, but also prevent sludge from sticking to the cylinder and lifting plate, making full use of the fast drying speed at the feed end and realizing the method of "stripping" layer by layer to make it dry quickly. High viscosity sludge drying equipment generally adopts hot air rotary vane dryer;
According to the viscosity of sludge, two-axis rotary vane dryers (vertical and horizontal) and three-axis rotary vane dryers (horizontal) can be used to dry high-humidity materials with initial moisture content below 85% to final moisture content below 12% at one time, and the drying time is short, generally 2- 10 minute. Because the high-speed stirring blades violently stir the wet materials, the wet materials can be in good contact with hot air. The moisture in the first half of the machine evaporates quickly, and the temperature of hot air in the machine drops sharply. Therefore, even if high-temperature hot air is used, the temperature rise of the material is not high. Typical applications include electroplating sludge drying, papermaking sludge drying, oilfield sludge drying, chemical sludge drying, mineral sludge drying, fruit residue drying, bean residue drying, sugar residue drying, peat drying, rare earth drying and other high-humidity materials, organic and inorganic compounds and chemical raw materials drying.