The rotary cylinder dryer is one of the traditional equipment, which is commonly used to dry fertilizer, grain, sand and other materials. It has the irreplaceable characteristics of other drying equipment. The drum dryer has large production capacity, simple structure, continuous operation and easy operation. After continuous optimization and improvement, it is still widely used in metallurgy, building materials and chemical industry. Rotary cylinder dryer play a vital role in fertilizer granulating production line.
Heat transfer in the drum dryer
When fertilizer, grain and sand enter the dryer, the direction of material movement is the same as that of hot air flow. The induced draft fan at the end of the dryer causes the hot air to flow out along the outlet of the dryer. The material exchanges heat with the air and the wall of the cylinder during the movement of the cylinder to evaporate water.
Residence time of material in drum dryer
The residence time of fertilizer, grain and sand in the dryer drum must be longer than the drying time of the material in order to ensure the drying requirement of the product. The residence time of the material in the dryer is related to the length of the cylinder, inner diameter, rotating speed, horizontal inclination angle and structure (with or without sheeting). According to the relevant factors, the appropriate parameters can be set to play the performance of the drum dryer and improve the production quality of the product.
Inclination angle of rotary cylinder dryer
The inclination angle of the dryer installation depends on the length of the cylinder and the residence time of the material. The angle between the dryer and the horizontal line is generally 0-8°, generally 1.5-3°, not more than 6°.
Rotary speed of dryer
The rotational speed range of rotary dryer is 1-8r/min, and the common rotational speed is 1-3r/min. If the diameter of the drum is large, the rotating speed should be smaller. When drying fertilizer and other materials, in order to ensure effective drying and increase the speed, the inclination angle of the rotary drum should be reduced.