Patent · US Expired

Refiner control

US6935164B2 · kind B2 · utility

2Cited by

7References

33Claims

0Family size

Assignee

ABB AB · SE

Inventors

Thomas Liljenberg · Hagfors, SE
Stefan Backa · Visby, SE
Lennart Thegel · Västerås, SE

Key dates

Filing date	Jun 27, 2001
Grant date	Aug 30, 2005
Priority date	—
Expiry date	Jun 27, 2021

Classification

Technology area (CPC G)Physics
CPC primaryG01N2291/02872
WIPO fieldMeasurement
WIPO sectorInstruments

Abstract

In the present invention a refiner (108) of a mechanical pulping line is supplied with a controllable acoustic source (14), arranged for emitting acoustic signals into the pulp fluid. The controllable acoustic signal is allowed to interact with the fibres in the pulp, and the acoustic (pressure) signals resulting from such an interaction is measured. At least one spectral component is measured. The measured spectral component is used to predict properties, content and/or size of the fibres. These properties may then be used to control the refiner (108) process. The used acoustic signal has preferably a wavelength that is large compared with a typical site of the particles.

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