Rotary dryer, also known as rotary drum dryer, is a type of industrial dryer employed to reduce or minimize the liquid moisture content of the material it is handling by bringing it into direct contact with a heated gas. The dryer is made up of a large, rotating cylindrical tube, usually supported by concrete columns or steel beams. Indirect heat transfer rotary dryer produced by our company is featured with a reasonable structure, well-produced, high yield, and low consumption, the advantages of operating convenience. In the indirect dryer, which is more suited to fine and dusty materials, there is little or no contact between the product and the drying gases since they are heated from the outside, via a stationary jacket fitted with either multiple burners or other external heat source.
Wet material from the belt conveyor or bucket elevator to the hopper, and then by feeder feeding through the feeding device into the terminal. Drum dryer cylinder into a slightly tilted to the horizontal rotating cylinder. Adding material from the higher end, low-end entry by the heat carrier, and the material into a counter-current contact, but also heat carrier and the material together and flow into the cylinder. With the rotating cylinder, the material runs by gravity to a more bottom end. Wet material in the cylinder body to move forward the process, directly or indirectly heating the heat carrier, the wet material to dry, and then the discharge end by the belt conveyor or screw conveyor sent. Tumble dryer wall of the cylinder body with lifting plate, its role is to copy the material up and planted, so that the surface of the material increases the contact with the air flow to improve drying rate and to promote material progress. Heat-carrier is generally divided into hot air, flue gas.
After heat-carrier around cylinder dryer back then, generally require cyclone trap the gas inside the material brought down. For further reduction of dust content in exhaust gas should be handled through the bag filter before discharge. After drying, the material is discharged from the low-end, the material residence time in the dryer about 20 to 40 min. Exhaust gas also flows from low pressure site to high pressure site. Material is unloaded from the dryer after drying and the exhaust gas is discharged to the atmosphere by the dust collector.Often, indirect heated dryers are used when product contamination is a concern. In some cases, a combination of direct-indirect heated rotary dryers are also available to improve the overall efficiency.
The Rotary dryers has been optimized a lot , which possesses the following characteristics :
1. The internal adopts assembled structure which has improved the accuracy of the equipment and it is easy to transport and install.
2. According to the characteristics of different fertilizers ,we have arranged the second granulation zone reasonably so as to improve the granulation effect .
3. Adopts assembled hoist board so as to exchange heat fully and lower the energy consumption .
4. Temperature induction monitor ,uniform vibration and airproof setting , which improve performance and productivity efficiently .
5. The assorted combustion furnace is a type of energy-efficient and has the characteristics of smaller area ,easy regulation and equipped with greenhouse .