Method and apparatus for minimizing steam consumption in the production of pulp for fiberboard and the like
US4136831A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 4, 1977 |
| Grant date | Jan 30, 1979 |
| Priority date | — |
| Expiry date | Aug 4, 1997 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21B1/12
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Method and apparatus for minimizing steam consumption in the production of pulp used for the manufacture of fiberboard and the like, in which chips of cellulosic material are ground in a defibrator or refiner in an environment of saturated steam above 100.degree. C and corresponding steam pressures. The chips are normally presteamed with atmospheric steam separated from the pulp at the discharge end of the defibrating process to a temperature between 90.degree. C and 100.degree. C and compressed and dewatered to a dryness of at least 50% and then passed into a preheater which forms part of the defibrating or refining apparatus, where the compressed and dewatered chips are heated to the desired defibrating or refining temperature, usually ranging between 130.degree. C and 200.degree. C, by a portion of the high-temperature high-pressure steam generated by the heat of friction in the grinding space of the defibrator, which portion, upon discharge from the grinding housing, is separated from the pulp and recirculated under increased pressure above the discharge pressure. If the other portion of the discharged atmospheric steam, upon separation from the pulp, should not have sufficient…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.