How Will Air Exhaust and Temperature Influence Product Drying?

Writer： admin Time：2020-10-16 14:16 Browse：℃

There are many factors that will influence the drying efficiency, today we will discuss about the air exhaust and temperature.

How will air exhaust and temperature influence product drying? The following example can tell us the answer that how the air exhaust and temperature influence the drying
 
There is a company whose product is granule preparation of traditional Chinese medicine. Several years ago, the company adopted hot air circulation oven and fluid bed drying machine for production. The general production processes were as follows: mixing extract, sugar powder and dextrin in proper proportion, adding moisturizer, stirring, sieving through 14-mesh screen and then drying in hot air circulation oven or fluid bed drying machine.
 
However, after drying, the product was not qualified. 200kg granules were dried but the moisture content of semi-finished products was above the acceptable level. There can be many causes, including inappropriate drying time and temperature, operation error in lab or in the workshop and so on. At last, the technical deputy minister checked the air exhaust system and found that the dust from fluid bed dryer clogged the system. Actually, not only time and temperature, but also exhaust air volume play a role in drying effect. Therefore, even if time and temperature were properly set, that the wet air cannot be exhausted still caused unqualified drying.
 
And two year later, still this company, it edited new production procedure for the granule preparation but set higher temperature for granule drying. During technical verification, the material was burnt and the verification failed. Through investigation, it was found that product’s features were not taken into account while formulating the procedure and that the drying temperature was beyond product’s endurance.
 
In fact, traditional Chinese medicines are of multiple varieties and have complex components. During traditional Chinese medicine drying, parameters should be controlled within a reasonable limitation and the product’s features should also be considered. Generally speaking, it is not practical to dry the traditional Chinese medicine of much sugar, strong viscosity, heat sensitivity and easy oxidation.