| 摘要 |
<p>Particulate or fibrous material, after treatment with gaseous reagents in a vessel (10) under pressure in a continuous process, is discharged from the pressure vessel (10) by entering a discharge conduit (20) in pressure communication with the pressure vessel (10), and is conveyed through the discharge conduit (20) by means of a feed conveyor (22) located therein. The feed conveyor (22) compacts the material to form a dense, substantially gas impervious plug thereof in the discharge conduit (20) against the outlet end thereof. The outlet end (34) of the discharge conduit (20) comprises an exit passage (38) of small cross-sectional area so as to cause compaction of the material therein by means of the conveyor (22). A valve means (42) is provided, movable rapidly between a fully open position and a fully closed position to permit passage of the cooked material therethrough, from the dense, compact plug formed in the outlet end (34) of the discharge conduit. Operating means (43,44) is provided to move the valve (42) rapidly between its fully open and fully closed positions, at predetermined intervals. In this means, the cooked material can be discharged intermittently at frequent intervals from a pressure vessel, allowing the pressure cooking process to be conducted continuously. The dense compact plug prevents reagent losses and pressure losses on discharge of the material. The process is particularly well adapted to the steam cooking of wood chips to produce fibrous cellulosic product.</p> |
