Internal modification of the rotary dryer is crucial. The investment for internal modifications is not substantial and relatively straightforward, but it is essential to understand the dryers structural principles, the types of materials being dried, and the accompanying dust collector setup. A feasible modification plan must be developed based on daily experience summaries. The general modification steps are as follows:

(1) The rotary dryer is equipped with a central X-shaped material lifting plate to reduce hot air voids, extend material residence time, improve heat exchange efficiency, and minimize the loss of high-temperature gas.

The installation can begin from the middle section of the dryer (later sections are also acceptable), sequentially installing 3 to 5 sets of lifting plates toward the head end, with intervals of 0.5 to 1 meter. Each set consists of 6 X-shaped lifting plates. However, no installation should be performed within 3 meters near the head end (due to the high moisture, high viscosity, and low temperature of the newly fed material, which may cause adhesion), as this would otherwise affect the overall drying efficiency.

(2) The rotary dryer removes the screw feeder blades from the feed end and replaces them with triangular ribs, which can be made of 6mm thick steel plates. The short leg height matches the height of the feed end baffle ring and is securely welded. The long leg length is 800mm, welded firmly to the inner cylinder of the dryer, with a welding circle every 50mm, naturally forming a conical feeder. Its function is to reduce material flow velocity in the high-temperature zone, fully absorb heat, enhance heat exchange efficiency, lower the temperature at the front end of the dryer, and prevent damage to the cylinder and baffle ring.

(3) Adjust the angle of the feed pipe. As long as it does not affect feeding, raise the discharge pipe as much as possible, ensuring the upper end does not contact the dryers material retention ring. However, the extension inside the drum should not be excessively long. The drop point can be controlled within 200mm of the retention ring to prevent material starvation at the front end and overheating damage to the retention ring and drum. By raising the discharge chute, both high-temperature gas circulation is facilitated and chute damage is prevented. The material naturally forms a curtain-like fall, directly exposed to high-temperature gases, thereby improving heat exchange efficiency.

(4) Modify the L-shaped lifter plate at approximately one-third the length of the drum in the tail low-temperature drying zone. Typically, the L-shaped lifter plate is fixed vertically at 90°, and can be welded sequentially around the circumference at angles of 30°, 90°, and 120°. This allows the lifter plate to distribute material over a larger area at varying heights in space through the rotation of the dryer, resulting in higher heat exchange efficiency.

The key to ensuring a dryers high quality and productivity lies in achieving a balance among "airflow, heat, and material.".

First, determine whether the dust removal and ventilation, dryer specifications and models, and the impact of modifications, as well as the heat supply capacity of the combustion furnace, are compatible.

Secondly, operational measures need to be strengthened:

①Feed the material evenly to prevent excessive moisture fluctuations;

② Adjust the heat source temperature promptly, and maintain stable furnace temperature and exhaust gas temperature;

③ The ventilation and dust removal equipment must operate normally to ensure balanced air volume and pressure. Only by mastering these key points can we achieve high production with low consumption, even under conditions of strong wind, large material flow, and intense heat.