Flattening Microwave Drying Machine
Conventional microwave drying equipments are heated by steam, which needs heating from inside to outside. The slow heating speed needs to consume a lot of coal. The microwave vacuum dryer uses electromagnetic wave heating, which does not need heat transfer medium, and directly heates to the inside of the object. The heating speed is fast. The microwave of 1 kilowatt can heat water at room temperature to 100 C in 3-5 minutes, thus avoiding the shortcomings mentioned above. Therefore, it has the advantages of high speed, high efficiency, shorter drying period and lower energy consumption. Compared with conventional drying technology, it can increase work efficiency more than four times.
Because microwave heating is used to heat the material from inside to outside at the same time, the temperature difference between inside and outside of the material is very small, and the inconsistency between inside and outside heating in conventional heating will not occur, resulting in the effect of expansion, conducive to crushing and greatly improving the drying quality.
In the 1980s, foreign developed countries began to develop industrial microwave vacuum dryer, and achieved good results in practical application. The French International Microwave Company processed seedless raisins by microwave vacuum dryer. The traditional process of 65 C, 24 hours hot air drying was changed to 50 C, 5 hours microwave vacuum drying. The product quality and output were greatly improved. In the late 1990s, our unit began to develop flattening microwave drying machine in China. Through several years of efforts, we completed the development of industrialized 10KW microwave vacuum dryer in 2000. It provides a new and efficient drying equipment for pharmaceutical engineering, biological engineering, chemical engineering, material engineering and deep processing of agricultural and sideline products.
Compared with abroad, in the application of microwave drying technology research in China started late, although many achievements have been made, but the application of microwave drying technology research field is narrow, mostly stay in the experimental stage or small-scale production stage, research subject to develop composite microwave drying technology, microwave drying of instantaneous heat transfer and mass transfer theory research is not enough, and microwave drying technology form a complete set of equipment and instrument development remains to be strengthened. In addition, although the application of microwave drying in natural rubber drying theoretical research has made great progress, but its scale, continuity and automation still have many problems to be solved, microwave drying on the molecular structure of rubber, non-rubber components and product performance and other aspects of the impact of further research. These are our future research priorities.