摘要 |
A method and apparatus are provided for effecting presteaming and deaeration of wood chips, or like comminuted cellulosic fibrous material. Presteaming takes place in a vertical presteaming vessel, utilizing a plurality of uniformly radially spaced nozzles adjacent the bottom of the vessel, a plurality of generally uniformly radially spaced steam introduction pipes in a central portion of the vessel, and a pair of synchronized rotating valves for feeding steam to the introduction nozzles and pipes in a coordinated manner. After presteaming, the chips pass through a chips meter to a vertical chute in which they are entrained in liquid, and then pass to a horizontal deaerating vessel. In the deaerating vessel, deaerated liquid is passed in a path generally perpendicular to the path of the material flowing through the deaeration vessel. The deaerated material discharged from the deaeration vessel passes through a vertical chute to a conventional high pressure feeder, and then is subsequently passed to the top of a continuous digester.
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