Special Structure of Large Fluidized Bed Dryer Machine

Special Structure of Large Fluidized Bed Dryer Machine

1. Dryer housing

According to the density and particle size distribution range of materials, manufacturers of large vibrating fluidized beds increase the width and height of the upper shell and reduce the wind speed to reduce the entrainment of gaseous dust. At the same time, polishing treatment should be applied to the surface inside the shell to avoid material accumulation on the wall.

2. Air distribution board and air chamber

In order to achieve uniform fluidization of materials, a strip shaped air distribution plate (orifice plate) and multiple air chambers are installed in the lower part of the fluidized bed, and the "square eye holes" on the air distribution plate have the same direction, facing the discharge port of the dryer, to facilitate the discharge of block materials.

3. Built-in heat exchanger

In order to improve heat transfer efficiency and reduce comprehensive energy consumption, four sets of heat exchange coils are installed above the air distribution plate (under normal operation, the coils are submerged by boiling materials), and the bottom of the coils is about 20cm away from the air distribution plate to facilitate the removal of block materials. Due to the erosion of boiling materials over a long period of time, the coil is prone to wear and leakage. Therefore, a dedicated extraction guide rail is set up in the bed for easy maintenance; Moreover, the outer surface of the coil and its fixing device is polished to reduce material adhesion.

4. Blending zone

The blending zone is located below the feed inlet and between two sets of coils. By adjusting the opening of the air valve, the air volume in the blending zone can be increased, which increases the fluidization speed in this area and quickly dries the wet material that falls, avoiding agglomeration and accumulation in the bed.

5. Overflow weir

The overflow weir is located at the outlet of the drying bed, slightly higher than the coil tube. An arc shaped baffle is installed above it, which can be adjusted outside the bed. The height can be adjusted between 0-30cm to control the residence time of the material in the bed and ensure the final moisture content of the dried material.