Abstract: Methods and apparatus for separating vapor from refined cellulosic material are disclosed. The method includes discharging the refined cellulosic material downwardly through an inlet opening into a discharge chamber maintained at substantially the same pressure as the refiner, deflecting the vapor laterally with respect to that cellulosic material, passing the vapor through the discharge chamber at a flow rate of less than 15 meters/sec. so that the cellulosic material carried by the vapor is separated from the vapor by sedimentation, and discharging the cellulosic material from the discharge chamber.

Abstract: Process and apparatus are provided for continuously conveying particulate compressible fibrous material from a first zone at a first gas pressure to a second zone at a second gas pressure with a pressure differential therebetween of at least 0.5 bar while retaining the prevailing gas pressure in each zone, which comprises:(1) continuously compressing the particulate material in the first zone into a gas-containing but gas-impermeable mass extending across the interface between the two zones;(2) continuously passing the mass of material out from the first zone into the second zone while maintaining the gas pressure within the mass constant at the gas pressure of the first zone; and(3) continuously breaking up the mass entering the second zone into particulate material.

Abstract: A screw conveyor is provided capable of maintaining a relatively uniform flow of conveyed material, even when operating well below its flow capacity, having a helical screw with a plurality of helical blade segments at one end, each segment extending over an arc of from about 100.degree. to about 130.degree. about the central stem of the screw, and having a pitch length within the range from about 0.5 to about 3 times the pitch length of the helical screw; the pitch length of the helical screw being from about 0.5 to about 1 times its diameter; the segments being spaced apart a distance within the range from about 0 to about 22 mm; the plurality of segments taken collectively defining a plurality of through passages extending axially along the central stem of the screw, and extending in uniformly spaced relationship .+-.10.degree. circumferentially about the 360.degree.