TMP refining of destructured chips
US7713381B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 7, 2007 |
| Grant date | May 11, 2010 |
| Priority date | — |
| Expiry date | Sep 7, 2028 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21D1/306
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A system for thermomechanical refining of wood chips comprises preparing the chips for refining by exposing the chips to an environment of steam to soften the chips, compressively destructuring and dewatering the softened chips to a solids consistency above 55 percent, and diluting the destructured and dewatered chips to a consistency in the range of about 30 to 55 percent. The destructuring partially defibrates the material. This diluted material is fed to a rotating disc primary refiner wherein each of the opposed discs has an inner ring pattern of bars and grooves and an outer ring pattern of bars and grooves. The destructured and partially defibrated chips are substantially completely defibrated in the inner ring and the resulting fibers are fibrillated in the outer ring. The compressive destructuring, dewatering, and dilution can all be implemented in one integrated piece of equipment immediately upstream of the primary refiner, and the fiberizing and fibrillating are both achieved between only one set of relatively rotating discs in the primary refiner.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.