PLG series Fluidized Spray Dryer (upper venting) is one of the most successful designs of spray dryers by now, which can be applied to various types of products, especially those products and materials hard for powder forming by traditional drying technologies.

PLG series Fluidized Spray Dryer (upper venting) combines the technologies of fluid-bed drying and spray drying, making it easy to control the shape and size of particles. Usually used for agglomeration or granulation of spray drying, this series of drying machine can not only complete the drying process under low powder temperature, but also enable perfect drying & forming of thermo-sensitive Products.

Advantages:
1. Able to generate free-flowing powders in the process of agglomeration, forming or granulating;
2. Little dust in the generated powders (called dust-free particles for short);
3. Able to dry thermoplastic and hygroscopic products that can not be processed by other equipment;
4. Ideal drying equipment for thermo-sensitive products due to low temperature of particles in the whole process of drying;
5. Available for high-efficiency energy utilization as drying is completed under low temperature of outgoing air.

Characteristics of PLG Spray Dryer:
(1) Four spray guns are provided, whereby the sprayed droplets collide and aggregate into large hollow particles to improve the solubility of powders.
(2) The drying tower adopts 18-20MPa high-pressure spraying, whereby materials are fully atomized and kept in sufficient contact with hot air to increase the heating area, improve the thermal efficiency and enable instant drying of products.
(3) The air distributing device is designed with multiple adjustable air ducts to ensure vertical downward flow of air in the tower, prevent bias flow and vortex, and reduce dust conglutination on the wall to the maximum.
(4) The air exhausting part is designed with four venting points at the top, and air is reversed to 180 degrees after reaching the bottom to increase the drying time of materials and efficiently utilize the hot air. The equipment enables even venting and can reduce dust conglutination on the wall to decrease entrainment in the cyclone separator and improve product yield.
(5) Fine powders in the cyclone and bag type cyclone dust collectors return from the tower top to the tower body and aggregate into big particles to improve the solubility of bean flour and protect the environment.
(6) Powders in the tower body enter from the bottom of cone coupling into the vibrating fluid bed for secondary drying, granulating and cooling. In this way, product quality and solubility are improved.
(7) The cooled power can be packed after screening by the vibrating screen classifier. The equipment of compact structure is designed with one powder outlet only to reduce powder loss and make it easy for operation.
(8) Condensed water is used for preheating of cold air to recover waste heat and extend the service life of heat exchanger.
(9) The cylindrical tower body with cone couplings is not designed with any other complex structures, thus easy for cleaning.
(10) The tower body is designed with a safety explosion door and explosion channel to prevent dust explosion caused by maloperation.
(11) Air hammers are provided at the lowest part of cone couplings of drying tower, bag type dust collector and cyclone separator, which are intermittently started up in sequence under control of a pulse control instrument to timely and efficiently shake off possible powders accumulated in the cone couplings.
(12) Cone angle of the tower is designed below 45°to ensure smooth falling of dust in the cone couplings.
(13) According to control requirements of various systems, an instrument box is provided for direct start-up and control of mechanical and electrical equipments, which is designed with display of inlet air temperature, exhaust air temperature, internal temperature of the tower, negative pressure in the tower body, as well as inlet air temperature and negative pressure of fluid bed.

Mode of Operation:
The liquid feed of solvent, suspension or emulsion is pumped into the atomizer (spray gun) in the air distributor at the top of tower.
Liquid is atomized and led into the high-speed flow of dry air, and the atomized liquid drops are driven by air flow into the built-in fluid bed, and dried into particles at the same time.
While particles enter the fluid bed, air flow is reversed upward and vented from the top of drying tower.
Fine particles separated from exhaust air are re-circulated into the drying tower body.
Fluidization of particles in the fluid bed, circulation of fine powders and movement of particles in dry air flow occur in an air environment with higher dust density than traditional drying system. The bonding problem of particle surfaces is solved, and those particles with high moisture content can be further processed.
Moisture content of particles in the fluid bed can be controlled with certain range to obtain larger particles and enable change of structure (agglomeration or granulation).
If required, the products can be finally dried and cooled in another external fluid bed connected to the outlet of the built-in bed.

Applications:
Chemicals: Cleaning agent, dye, fertilizer, inorganic and organic salts, insecticide and tannic acid etc.
Medicine: Analgetics, antibiotics, plasma, enzyme and vitamin etc.
Polymers: e-PVC, styrene, UF and PF resin etc.
Food: Coffee, dairy products, egg products, condiments, maltodextrin, soup bases, vegetable protein and yeast etc.

Attentions before Order:
Liquid name and property: solid contents(or water contents), viscosity, surface tension and PH value;
Dry powder density residual water contents allowed, particle size, and maximum temperature allowed.
Output: shift time daily;
Energy that can be available at user’s site: steam pressure, electricity properly,fuel of coal, oil and natural gas;
Control requirement: whether or not the inlet and outlet temperatures should be controlled. Whether the whole control system should be fully automatic or semi-automatic;
Powder collection requirement: whether it's necessary to use cloth bag filter and the requirement of the environment of the exhausted gas. Other special requirements.