The steam tube rotary dryer is a closed indirect heating rotary dryer, featuring the following characteristics and applications:

Working principle

The steam tube rotary dryer provides heat by installing steam heating tubes inside the cylinder. These heating tubes run through the entire dryer body and are arranged in several concentric circles (generally 1 to 4 circles). The heat required for drying is mainly provided by the heating tube, while the drying effect of the carrying gas can be ignored. Its purpose is to carry the volatile components. The materials are conveyed to the rotating cylinder by the screw conveyor, indirectly heated by the heat exchange tubes, and finally lifted by the discharge lifting plate and discharged through the material guide pipe.

Structural composition

This dryer is mainly composed of a rotating drum, a feeding screw, a supporting device for rollers, a discharging box, seals at the feeding and discharging ends, rotary joints and a transmission system, etc. One end of the heat exchange tube is welded to the steam chamber, and the other end is sealed with a pipe plug, which is the free end and can expand freely when heated.

Application field

Steam tube rotary dryers are widely used in the drying of materials such as HDPE (high-density polyethylene) and PTA (purified terephthalic acid) in the petrochemical industry, coal moisture regulation (CMC) in the metallurgical industry, gypsum calcination and heavy alkali calcination in the building materials industry, and other processes. It is also used for the drying of lignite in lignite power plants to enhance the utilization efficiency of lignite resources and the economic efficiency of power plants.

Operating characteristics

Large processing capacity: The steam tube rotary dryer has a relatively large processing capacity.

Good sealing performance: Suitable for drying materials containing organic volatile components, ensuring the safety of the operation process.

Large operational flexibility: The drying heat source can be steam, and lignite, long bituminous coal and coking coal can all be dried. The range of coal drying particle size is wide.

Stable operation: It can achieve long-term continuous operation, with high reliability and low maintenance costs.

Environmental protection and energy conservation: During the drying process of the steam tube rotary dryer, the exhaust gas flow is small, and it is less likely to carry dust. Moreover, due to the high moisture content in the exhaust gas, it is conducive to the recovery of special solvents and waste heat in the exhaust gas, thereby achieving a dual effect of energy conservation and environmental protection.