Rotary steam tube dryer is an efficient and environmentally friendly drying equipment. Unlike traditional dryers, it uses waste heat steam as a heat source, indirectly heated by tubes, and converted into the temperature and heat required for material drying through technology. So, how does the rotary steam tube dryer work?

  The following is a case study of the application of steam tube dryer in coal slime drying production line, taking it as an example:

  The steam coal slime dryer equipment mainly consists of a tube heat exchanger, a heat source inlet and outlet center pipe, a rotary drum, an inlet and outlet machine, an induced draft fan, a dust collector, and a distribution cabinet. Wet coal slurry is fed into the dryer through a conveyor belt. Under the uniformly distributed lifting plate and tube flipping inside the drum, it fully contacts with the thermal conductive hot oil (steam) tube heat exchanger, achieving heat and mass transfer at 110-250 ℃. The moisture in the material vaporizes and disperses, and is discharged with the airflow. The moisture in the material gradually decreases until it reaches the target moisture level, and is discharged through the discharge port. This drying method not only has high heat utilization efficiency, but also relatively low cost and easy operation, so it has been widely used in many industries.

  The drying process inside the rotary steam tube dryer is a complex process of heat and mass transfer. In terms of heat transfer, there is not only contact heat transfer between the dried material particles and the tube, but also convective heat transfer between the tube and the moisture carrying gas, between the moisture carrying gas and the material particles, as well as heat conduction between the material particle layers. In terms of mass transfer, in addition to convective mass transfer between material particles and the moisture carrier medium and moisture diffusion inside material particles, there are also complex moisture diffusion processes between relatively stationary particle clusters. As the dryer rotates, the particle movement state inside the dryer constantly changes, and the corresponding heat transfer characteristics will also undergo significant changes.

  Compared to traditional dryers, steam rotary dryers have stronger adaptability and can be applied to various wet materials such as coal slime, coal, distiller's grains, coffee grounds, tea residue, etc., while also being more environmentally friendly. If you have any questions, please feel free to contact us.