| In the process of making PVA water-soluble film, drying method and drying parameter will influence the production efficiency and quality of PVA film in drying system. In order to define a suitable method and technological parameter to dry the PVA water-soluble film by casting on steel band,in this paper,customary proportion of industrial PVA hydrosols was studied. First, a test of drying thin layer of PVA hydrosols by hot air is established. It studies the drying and forming of film by Changing air temperature, wind speed and other factors. And it is found that the regression model of hot air drying on PVA hydrosols film with the equation of Page with the regression analysis. Meanwhile, the equation can describe the relation between moisture content and drying time in the process of dehydrated thin layer of PVA hydrosols; then, after the analysis, the feasibility that infrared radiation applied on drying PVA hydrosol is established. After a while, the orthogonal experiment of infrared radiation drying and combining infrared and hot air have been conducted. Then the results of these three ways of drying are studied and the dehydrating characteristics are obtained; finally, to find a reasonable dry technology for PVA film in Industrial production, the quality control of PVA film in practice is discussed, and some infrared heating devices are added to the production line for inspection experiments. Then, the experiments of combining infrared and hot air drying are also studied. The influence of factors to the index is analyzed. And the technological parameters for industry are determined. The results show that, combining infrared and hot air drying method can effectively increase the drying rate of thin layer PVA film. And its effect is embodied in the forepart of drying process. Meanwhile, the drying method about combining infrared and hot air for PVA water-soluble film has good effects on the improving of casting equipment of the PVA water-soluble film in industrial production.
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