Chip pumping to a digester

A system for feeding comminuted cellulosic material entrained in liquid to a high pressure feeder connected to a digester, comprising:

• a vertical treatment vessel having a discharge at the bottom thereof;
• a metering device connected to the discharge of said treatment vessel;
• a generally vertical chute extending downwardly from said metering device;
• a high pressure feeder connected to a digester;
• a slurry pump for pumping a slurry of comminuted cellulosic material in liquid, said slurry pump having an inlet, and said pump connected to said high pressure feeder;
• said chute operatively connected to said slurry pump inlet;
• a substantially vertical liquor tank having a top and a bottom, said bottom including a discharge opening therein;
• and
• a conduit directly connecting said liquor tank discharge opening with said slurry pump inlet.

A slurry feeding system for feeding a slurry of comminuted cellulosic fibrous material treatment system comprising:

• a substantially vertical pretreatment vessel;
• means for metering the flow of comminuted cellulosic fibrous material from the pretreatment vessel;
• means for entraining the metered comminuted cellulosic fibrous material in liquid to form a slurry;
• a slurry pump having an inlet;
• means for feeding the slurry to the inlet to the slurry pump;
• means providing a separate supply of liquid to the inlet to the slurry pump to facilitate the transfer of comminuted cellulosic fibrous material to the slurry pump to permit separate control of liquor and comminuted cellulosic material volumes, and to minimize the effect of changes in liquid volume upon operation;
• a high pressure feeder having a low pressure inlet and a high pressure outlet;
• a digester;
• means for transporting the slurry under the influence of the slurry pump to the low pressure inlet of the high pressure feeder;
• and
• means for transporting the comminuted cellulosic fibrous material from the high pressure feeder to said digester.