The characteristics of the airflow tube coal drying technology are as below. (1). the large drying strength: because of the high air velocity, the particles are well dispersed in the gas phase, it can put the entire surface area as the effective drying area; (2). the drying time is short: the contact time between the two phrases of gas and solid is short, it is generally dried in 0.5-2 seconds or for a maximum of 5 seconds; (3). the thermal efficiency is high. The higher the airflow drying gas inlet temperature, the higher the thermal efficiency and it is generally above 60%; (4).The processing amount is large; (5). the equipment is simple.
Airflow tube dryer has simple structure and occupies less area. It requires little investment and is easy for automatic control; (6). The application range is wide. Airflow tube drying can be used for all kinds of powder and granular materials.
The rotary dryer with flue gas as the heat medium is a conventional coal drying technology, and widely used in drying various coal property and coal slime. The Drying Engineering Center makes technological advances and upgrades to the traditional technology and develop technology of rotary drying with closed circulating inert gas, which not only maximizes the reduction of operating cost, but also uses patented sealing technology to seal inlet and outlet of the dryer, the system is in full closed operation, safety
and environment friendly. The technology has been applied in the first section drying system of coal catalyst for Shenhua coal oil device and runs well.