Direct Fired Rotary Dryers, Commercial and Pilot Scale,
for processing at temperatures up to approximately 1,200 °F (635 °C)
Direct Fired Rotary Calciners
A directly heated rotary dryer from Thermal Processing Solutions can be gas or oil fired, or hot air utilizing a heat exchanger or heating elements fired in a parallel flow or counter flow arrangement. Utilization of a heat exchanger allows the use of a dry gas such as air or nitrogen as the heat transfer media. In a direct fired dryer, heat transfer rate and process atmosphere composition/volume are dependent, therefore consideration must be given to the compatibility of the process material with the drying gas composition as well as the gas velocity. The direct heated dryer is subject to limited temperature profiling due to the single point source of heat.
TPS direct rotary dryers are suited to applications requiring:
- Processes requiring limited control of the process gas composition.
- Oxidizing, slightly reducing, and high humidity gas compositions possible.
- Processes that require limited isolation
- Processes with reaction kinetics improved by solid/solid or solid/gas contact
- Materials that are conduction heat transfer limited, and benefit from the dynamic exposure to a radiant heat source
- Processes requiring gentle heating
- Processes that require a volatile component to be thermally stripped from a substrate
- Materials that will tolerate a temperature profile limited by a single heat source
- Materials not sensitive to entrainment. Sufficiently coarse particle size distribution or high specific gravity to tolerate the process gas sweeping velocity
Indirectly Heated Dryer
An indirectly heated rotary dryer is essentially the same arrangement as the indirectly heated calciner, but is designed for operation at much lower temperatures. The indirectly heated dryer is used principally to desorb volatiles from solids. It is applied in drying applications where in applications where the process must remain isolated or the particle size is fine.
Click here for the full technical details of our indirect rotary dryers (PDF 177k)