Applicable for drying slurries and solutions as well as wet powder and pastry cake. Air classifier integrated flash dryer for every segment of industries. It is not possible to control dried product particle size with ordinary flash dryer. Product moisture content is not stable when drying paste or cake material by flash dryer. The combination of the intensive dispersion mechanism with high performance classifier brings the stable product quality; particle size and moisture content. Intensive dispersion effect on material in compact drying chamber leads the high thermal capacity coefficient and the compact system design. Compared to conventional Drymeister, DMR-H can (1) induce inlet air temperature up to 600°C, (2) increase capacity by 40% and (3) improved thermal capacity coefficient.
(DRYMEISTER is a registered trademark of HOSOKAWA MICRON CORPORATION in Japan)
Fig.1 Schematic structure
DMR-H is constructed with vertical cylindrical casing, grinding rotor at the bottom, feed inlet at the side, hot gas inlet at the bottom and classifying rotor at the top. Wet material is fed from the feed inlet down to grinding chamber to be dispersed and to meet hot gas. Where, highly effective heat transfer is taken place. Ground and dried powder is carried up to classifying zone. Fine particles go through the classifying wheel and transported to bag filter. Coarse particles fall down to grinding chamber for further grinding drying. Particle size of the product is controlled by the rotor speed of the classifier. Moisture content of the product is controlled by the outlet gas temperature of the dryer. DMR-H drying system consists of the screw feeder, Drymeister, heater, bag filter, blower and control cabinet. In case of drainage recovery is necessary, condenser and/or scrubber may be added. Gas circulation system with super heated steam brings good quality of product with energy saving (40% reduction).
Fig.2 Upper interior view
High dry ability and no adhesion inside
High speed rotor generates strong vortex which disperses the wet material and conducts rapid heat transfer. There is no stage for wet material sticks on machine interior.
Non adhesion in grinding chamber
Heated grinding track gives no adhesion on surface.
Fine and dry product
Intensive dispersing mechanism with high speed classifier performs three operations (grinding, drying and classifying) within seconds and produces the fine and dry product.
Easy control of particle size
Classifier speed directly determines the particle size of the product.
Easy control of moisture content in the product
Outlet gas temperature determines the moisture content of the product, although classifier speed influences the resident time of the material in dryer.
Superior dispersion leads high thermal capacity coefficient which realizes compact system design. Smaller system represents much better maintenaceability. Less than half of spray dryer system.
High energy efficiency
Saving energy by 50 – 70% less than spray dryer/rotary dryer. Inlet gas temperature of 600°C gives even better energy efficiency.
Construction material of ceramics for the powder contact parts.
Specially designed screw feeder for cake material.
Wide application references in various industrial field, from inorganic material to organic material, is show in Table 1.
Table 1 Application references
Fig.4 Saving the running cost
By the design of closed loop drying system with Drymeister, energy saving becomes considerable. Controlling above dew point operation, 70% of energy could be saved.
Fig.5 Flow of closed loop drying system
Table 2 Relationship between product moisture and outlet temperature of dryer