How does a three-cylinder slag dryer achieve effective continuous drying?

A three-cylinder slag dryer replaces the single-cylinder dryer with three nested cylinders. During operation, material and hot air flow sequentially into the inner and outer cylinders. After being deflected and folded in a Z-shaped pattern, the material is fully dried by utilizing heat energy before being discharged, achieving effective heat energy recycling.

During the drying process, the three-cylinder slag dryer employs a unique drying process combining co-current and counter-current flow. The slag first enters the inner layer through the feeding device, achieving co-current drying. Under the action of the lifting plates in the inner layer, the slag is continuously lifted and scattered, spiraling forward to exchange heat with the hot air flow.

Subsequently, the slag moves to the other end of the inner layer and enters the middle layer for counter-current drying. In the middle layer, the slag moves in a two-steps-forward-one-step-back manner, fully absorbing heat from both the inner and middle cylinders, while extending the drying time and ensuring the material reaches an optimal dry state. The slag falls into the outer layer and travels in a rectangular multi-loop pattern within the outer drum. Material that has reached the desired dryness level is rapidly discharged from the drum under the influence of hot air, while wet material that has not reached the desired dryness level cannot move quickly due to its own weight and undergoes thorough drying within the rectangular lifting plates, thus completing the drying process.

To further improve drying efficiency, the three drums employ variable frequency speed control technology, which can adjust the drum speed according to the moisture content and output requirements of the incoming material to ensure that the needs of the next process are met. Simultaneously, the inclusion of an automatic temperature monitoring system makes operation more convenient, enabling real-time monitoring and adjustment of the dryer's internal temperature to ensure the stability and effectiveness of the drying process.