Patent · US Active

Processes and systems for the pulping of lignocellulosic materials

US8262851B2 · kind B2 · utility

2Cited by
8References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 18, 2007
Grant dateSep 11, 2012
Priority date
Expiry dateJul 1, 2029

Classification

  • Technology area (CPC D)Textiles; Paper
  • CPC primaryD21C9/16
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

A non-compression vessel, such as a digester, is employed for the chemical preconditioning of the chips followed by a fiberizing device to break the preconditioned chips down to fiber bundles, which are then washed before a high consistency chemical treatment. The digester may be one such as used in conventional chemical pulping of wood with or without screens for the extraction of chemical. If extracted this chemical could be recirculated to the digester with treatment in the circulation loop such as heating or the addition of dilution or other chemicals. This digester may be hydraulic or vapor phase (that is contain a vapor space within the digester), and operate in either a continuous or batch fashion. This digester allows for the discharge of material without the use of a screw mechanism. The digester treated material is then defiberized to convert the chips into course fiber bundles, which then is washed and dewatered. The washed and dewatered pulp is then treated with alkali peroxide chemicals to develop brightness and other pulp properties.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.