FGBX  Sealed -circuit Circulation Fluidizing Dryer

Description
Usually, for the synthetic drugs, they are crystallized in organic solvents. Meanwhile, they contain a considerable number of organic solvents. If these solvents are directly discharged into the atmosphere, they will not only pollute the environment heavily but also cause energy waste. So, recovering and recycling all kinds of the solvents from the raw material and drugs when drying the raw material and drugs of the medicine meets the requirements of environmental protection as well as the enterprise development. In the point, to dry the raw material medicine and partial medicine, choosing the closed-circuit circulation drying system is more suitable. The system helps to realize a more effective unity of economic, better environmental and social benefits.

Advantages compared with the traditional drying equipments

1. It can effectively recover organic solvents, reduce production costs, and avoid the environmental pollution caused by the solvents.
2. It can make the material dry with lower water content (the moisture content can be reduced to 0.5%) under a low temperature of drying medium (generally nitrogen).
3. During the drying process of the closed-circuit circulation fluid bed dryer, the wet and hot air containing the solvent enters the condenser and let the solvent in the air become liquid state. In this way, it not only recovers the solvent, but also condense the dehumidify and dry the air. For the recovered solvent, it can be reused as to save the cost. Meanwhile, the exhausted air will not cause the pollution to the environment. After the condensing and dehumidifying, the absolute humidity in the air is low, the drying capability of the dryer becomes stronger. It is more suitable for drying the material moisture-absorbing for closed- circuit circulation fluid bed dryer.During the drying process of the closed-circuit circulation fluid bed dryer, the wet and hot air containing the solvent enters the condenser and let the solvent in the air become liquid state. In this way, it not only recovers the solvent, but also condense the dehumidify and dry the air. For the recovered solvent, it can be reused as to save the cost. Meanwhile, the exhausted air will not cause the pollution to the environment. After the condensing and dehumidifying, the absolute humidity in the air is low, the drying capability of the dryer becomes stronger. It is more suitable for drying the material moisture-absorbing for closed-circuit circulation fluid bed dryer.
4. The sealed -circuit circulation fluid bed dryer is with fully -closed structure. the circulation air inside the machine is nitrogen. During drying anaerobic materials or materials containing flammable and explosive organic solvents, because of the low oxygen in the circulating air, the material in the dryer cannot be burned or oxidized. In this way, the system effectively avoids the occurrence of fire or explosion accidents in the producing process, with the higher-level safety class.
5. The sealed-circuit circulation fluidizing dryer requires low air pressure inside when it is working with only a slight positive pressure needed. Thus, the equipment is equipped with a relatively low power of the fan. Under the positive pressure condition, the hot air is blown up from the bottom of the material mesh board. The air penetration capability is strong. Although the material fluidizing height is not high, the hot air and material contact with each other more fully, and the drying speed is faster. At the same time, the energy consumption is reduced.
6. The main machine of the closed-circuit circulation fluid bed dryer adopts specially-made pulse back-blown dust removal system. The dust removal effect is good. The filter element is made of special material, with the good surface finish quality, the large filtering area, the high filter precision, and the low resistance. In this case, the dust is not easy to adhere to the filter cylinder, but easy to disassemble and clean.

Principle
1.Nitrogen filled and oxygen dump
When closing the corresponding pipeline control valve, the system is in a completely closed state; when open the exhaust air pump, the oxygen in the system will be pumped out as to let the system reach a micro-negative pressure state. When the system pressure gauge shows a certain value, to close the corresponding exhaust valve as well as the exhaust air pump. At this time, the nitrogen control valve is opened and nitrogen is filled into the system. When the oxygen residue in the system is less than the required value detected by the on-line oxygen detection device, the system is in a micro-positive pressure state. At this moment, to close the the nitrogen control valve and enter into the next process.
2.Drying Period
Open the circulation fan and make the material fluidize well; open the radiator to heat up the system to the required temperature. Through the nitrogen transferring, the heat brought out the moisture and the organic solvents in the material as well as a small amount of micro-powder. In the system, the fine powder is collected by a dust collector (filtered to 2-5μm). After going through the condenser, the solvent and organic solvent inside the air are condensed into the liquid, which is collected by a storage tank. The nitrogen becomes dry after dehumidified and condensed, and circulated inside the system by the fan.
3.Nitrogen protection system
The nitrogen protection is mainly controlled by on-line oxygen detector. When the oxygen content exceeds the required value, the nitrogen filling device is automatically opened and fill the nitrogen into the system. When the oxygen content in the system meets the requirements, the nitrogen filling device is automatically closed.
4.Overpressure protection system
When the pressure in the system exceeds the set value, the pressure detection device acts and automatically empties and relieves the pressure. When the system pressure meets the requirements, close the automatic exhaust valve, and the system is running normally.
Parameters

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