Capillary dewatering method and apparatus

摘要

The invention relates to a system for reducing the moisture content of a paper web in a papermaking process, comprising: a rotating capillary dewatering roll that has a capillary membrane with capillary pores therethrough which have a substantially straight through, non-tortuous path, the capillary pores having a pore aspect ratio of from about 2 to about 20; wherein the capillary dewatering roll is a non-sectored roll such that the vacuum pressure within the capillary dewatering roll is substantially the same throughout; means for pressing a web to the capillary membrane to ensure hydraulic contact between the water contained in the web and the water in the pores of the capillary membrane, and means for spraying the capillary membrane with a cleansing fluid to wash the surface of the capillary membrane and to flush any particulates trapped within the capillary pores through the substantially straight through, non-tortuous capillary pores to the inside of the rotating capillary dewatering roll. In another aspect, the invention relates to a respective method of removing water from a wet porus web in a papermaking process without substantial overall compaction of the web. <IMAGE>