Scale deposit inhibitor for kraft digesters and method for controlling scale deposition in kraft digesters
US5409571A · kind A · utility
20Cited by
32References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 1, 1994 |
| Grant date | Apr 25, 1995 |
| Priority date | — |
| Expiry date | Feb 1, 2014 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21C3/226
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A scale deposit inhibitor and a method for continuously controlling scale deposition applicable to a digester and its peripheral equipment used in kraft pulp manufacture are disclosed, the scale deposit inhibitor comprising a maleic acid-acrylic acid-hypophosphorous acid terpolymer having a maleic acid unit to acrylic acid unit molar ratio of 1:4 to 4:1, a hypophosphorous acid unit content of 1 to 12 mol %, and a weight average molecular weight of 500 to 10000. The scale deposit inhibitor is added to a cooking liquor in a concentration of 0.01 to 10 ppm per ppm of a calcium ion in the cooking liquor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.