Abstract:

Silica from the silica gel mSiO2 · nH2O appropriate dehydration from the solid particles of different sizes of the porous material. Its structure is very similar characteristics and uses activated carbon. Wet steam in the air and dust particles has a strong adhesive force, the role of a large number of desiccant, clarifying agent, also used as a catalyst carrier. Packaging engineering make extensive use of silica gel desiccant, generally use the traditional method of heat drying, oven baked with a spare 24 ~ 48h. Conventional heat drying because of poor thermal conductivity, porous desiccant adsorption of molecular force caused by the presence of water within the evaporation of the difficult, from the heated drying cycle to the long, power-consuming. In addition to water depth and difficult to achieve the purpose. According to the principle of microwave heating and microwave heating practice, repeated studies in composition and moisture absorption mechanism of silica, based on the use of polar molecules desiccant silica gel has a high microwave magnetic loss characteristics of industrial drying process to carry out research. According to the performance of commercially available silica gel indicator, moisture absorption rate of 31% or more, provided the chart [2] showed that the rate of silica gel up to 37% moisture, wet should be enough electromagnetic absorbent. Dynamics by microwave drying, microwave heating of water caused by the direct vaporization of the water jet can be formed out of steam pressure, driven by absorbed water inside the silica gel capillary structure along the outward movement, which greatly improved the water discharge rate.