Strategies for High Vacuum Dewatering on Paper Machines
نویسنده
چکیده
The Paper machine vacuum system is an important operation for dewatering of wet web to increase percentage solids in web. There are various models available to assess the influence of vacuum on the above parameters. In this present investigation the steady state model is discussed for estimating optimum vacuum load in flat boxes of Fourdrinier paper machine as the flat boxes are the main components to dewater the sheet in this section as well as wire and felts in the paper machine. From the detailed investigation it has been found that for a given furnish and vacuum level, there is an ultimate achievable dryness of the web beyond which the sheet will not undergo further drying , no matter what the length of exposure is. There are two main factors in vacuum dewatering the ultimate achievable dryness for that vacuum, and the rate at which that dryness is attained. This paper also indicates the effect of temperature and slots design for vacuum dewatering.
منابع مشابه
Rewetting and forming fabric structure
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