Boiling drier; also called fluidized bed; after 30 years of use; improvement; at present in the pharmaceutical, chemical, food, food processing and other aspects; it reflects the increasingly important role. It is composed of air filter, boiling bed main machine, cyclone separator, bag filter, high pressure centrifugal fan, operation table. Due to the nature of the different drying materials; ancillary dedusting equipment; can according to need; simultaneous selection of cyclone separator, bag dust collector; one can also choose one. Generally speaking; materials with larger specific gravity simply select the cyclone separator. Lighter weight materials need to be supporting the bag dust collector; and a pneumatic feeding device for choice.
Boiling drier in the distribution plate has two functions, one is the supporting material layer, two is the uniform distribution of gas. The distribution plate hole size, shape, distribution, porosity and so on fluid distribution is very important. Gas distribution is not uniform, will make the bed in a "Circulation", which tend to be extremely easy to make some parts of the bed layer in a "channeling", while the remaining part is the death bed, then most of the gas along some channel bed in order to "form short channeling" through the bed away, the gas solid contact much worse, it should be to avoid. Design of the distribution plate good, should not uniformity appears to suppress the bed, namely when the bed layer in certain parts of the pressure drop, flow velocity increased, generated by increased distribution board should be able to prevent the flow resistance, thus suppressing deterioration of fluidization.
At present the majority of boiling dryer using the air distribution plate form is single, the perforated plate or mat shape net vertical, the material in the fluidization process is easy to appear the fluidization uneven or the dead angle and so on, can not ensure the uniformity of particles in drug, while a single hole form cannot meet the requirements of different production process drugs. On the other hand, in order to reduce the leakage loss of drugs, the current widespread use of multilayer network structure, the airflow distribution board and the bed body with a bolt fixing, inconvenient disassembly, not easy to clean and problems caused by residual cross contamination etc.. Recommendations: the use of computer fluid dynamics model of heat and mass transfer, model, distance, the hole in the air distribution plate design aperture, porosity parameters such as aerodynamics, Thermodynamics Simulation and verification, to meet the requirements of the production process of different materials. In the installation, connection is made detachable, in order to ensure quick and thorough, complete cleaning. |
Boiling drier in the distribution plate has two effects