Procedure and apparatus for preparing hot groundwood
AssigneeYhtyneet Paperitehtaat Osakeyhtio Jylhavaara
InventorAhti Syrjanen
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Abstract
Procedure for preparing hot groundwood from wood chips, wherein a chip stream is conducted into a pressurized steaming chamber, where the chips stay a few minutes and are heated to a temperature higher than 100.degree. C., and from the steaming chamber through a sluice feeder into a hot grinder of enclosed construction, i.e. the stage I grinder, when the pre-ground groundwood is conducted through a separating cyclone into a stage II grinder, the groundwood derived herefrom being conducted towards further treatment steps. The pre-ground groundwood is conducted from the steam separating cyclone through a sluice feeder into the stage II grinder. The stage II grinding is carried out in a hot grinder of enclosed construction.
Claims5
In a process for preparing hot groundwood from wood chips, wherein a chip stream is conducted into a pressurized steaming chamber, where the chips stay a few minutes and are heated to a temperature higher than 100.degree. C, and from the steaming chamber is conducted through a sluice feeder into a hot stage I grinder of enclosed construction, whence the pre-ground groundwood is conducted through a separating cyclone into a stage II grinder, and the groundwood from the stage II grinder is conducted towards further treatment steps, the improvement which comprises the step of conducting the pre-ground groundwood from the steam separating cyclone through a sluice feeder into a hot stage II grinder of enclosed construction and conducting steam generated by the stage II grinder into the steam separating cyclone.
In an apparatus for preparing a hot groundwood from wood chips comprising a steaming chamber, a sluice feeder, a hot stage I grinder of enclosed construction, a steam separating cyclone, a stage II grinder and a hot groundwood output line leading from the stage II grinder, connected so that a chip stream passes consecutively therethrough, the improvement comprising a sluice feeder located between the steam separating cyclone and the stage II grinder;
- a hot stage II grinder of enclosed construction and a steam pipeline connecting the stage II grinder to the steam separator.
Dependencies are inferred from the claim text.