Patent · US Expired

Method of refining wood chips or pulp in a high consistency conical disc refiner

US7240863B2 · kind B2 · utility

5Cited by
11References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 20, 2005
Grant dateJul 10, 2007
Priority date
Expiry dateAug 13, 2025

Classification

  • Technology area (CPC D)Textiles; Paper
  • CPC primaryD21D1/38
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

A method is proposed for improving pulp quality at high production rates on conical disc refiners. It permits a reduction in refining intensity by enabling fibre residence time to increase by increasing consistency, while avoiding the problem of plate plugging normally associated with high discharge consistency. In practice, inlet consistency is increased by the in-feed dilution, flat zone dilution or both, but without allowing the discharge consistency to rise. Instead, the discharge consistency is controlled at a fixed optimum value by the addition of dilution water within the conical zone. The result is that residence time is increased, and refining intensity decreased, by raising the consistency in the inner region of the refining zone, while avoiding the plate plugging caused by excessive consistency in the outer region of the refining zone.

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