| 摘要 |
A process for producing alkali pulp by using a single, cylindrical pressurized reaction vessel having therein a liquor-inpregnating zone, a cooking zone, a washing zone, and a diluting zone in that order, and having a motor-driven scraping or agitating device and a pulp discharging outlet in the end portion of the diluting zone. Alkaline aqueous medium containing dissolved oxygen therein is introduced into the diluting zone. A part of the introduced alkaline aqueous medium countercurrently contacts cooked cellulosic materials transferred from the washing zone to the diluting zone to proceed with oxygen-alkali delignification, and is finally discharged out of the vessel from the end portion of the cooking zone. The remainder of the introduced alkaline aqueous medium contacts the cooked cellulosic materials in the diluting zone in a scraping or agitating manner by means of the motor-driven scraping or agitating device to proceed with oxygen-alkali delignification, and finally serves as diluting liquor to be discharged out of the vessel accompanying the resulting pulp. |
