Apparatus for the production of mechanical wood pulp

An apparatus for the manufacture of wood pulp with a grinder located in a housing in which wood stock is ground up to form a slurry of mechanically ground wood in a trough located below the grinder, comprising:

• a discharge conduit unrestrictively coupled to a lower end of the trough to convey ground wood therefrom;
• a valve interposed in the conduit;
• and
• means for generating a signal indicative of the level of the slurry in the trough to actuate the valve and control the discharge of ground wood from the trough through said conduit while maintaining the slurry level above the discharge conduit.

An apparatus for the mechanical production of wood pulp with a grinder located in a housing pressurized with a gas from a supply with wood stock being fed through a pressure lock into the housing to be ground up by the grinder for formation of a slurry of ground wood in a trough below the grinder, comprising:

• a discharge conduit coupled to a discharge port located at a lower end of the trough to convey ground wood therefrom, said discharge conduit being in unrestricted ground wood flow communication with the slurry of ground wood below the grinder;
• valve means interposed in the conduit for regulating the flow of ground wood slurry from the trough;
• and
• means coupled to the trough for generating a signal indicative of the level of the slurry of ground wood therein and actuate said valve means for regulation of the flow of ground wood from the trough.