Title:
INFILTRATION FOR FINELY CRUSHED CELLULOSE FIBROUS MATERIAL AND APPARATUS THEREFOR
Document Type and Number:
Japanese Patent JP3682935
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a method for improving the mechanical strength characteristics of chemical cellulose pulp (esp. kraft pulp).
SOLUTION: The mechanical strength characteristics of chemical cellulose pulp is improved by low-temperature dipping infiltration method instead of conventional dipping method. Specifically, this method is as follows: wood chips, after subjected to steam treatment, is dipped in an alkali solution at about 80-110°C for 30min to 72h under a pressure of about 0-15 bar and dissolved at ≥8wt.%, and ≥15wt.% lignin is also dissolved. Although the alkali solution to be used pref. contain sulfide(s), any kind of alkali may be used provided that the alkali concentration is about 1.0mol/L in terms of NaOH. Subsequently, the wood chips is cooked at about 145-180°C to produce cellulose chemical pulp. Such an intermediate process that the wood chips is heated at about 110-150°C for 10-90min may be provided between the dipping process and the temperature-raising process (to the crooking temperature). For the wood chip treatment unit, a low-pressure dipping tank (together with related pump's) and other carrying means) has only to be equipped in addition to conventional equipment.
Inventors:
Casio. Henrixon
Aki Hannu Birupponen
Hannu Oravi Lamark
Ouvochimo Kötznen
See. Bertil Stronberg
Aki Hannu Birupponen
Hannu Oravi Lamark
Ouvochimo Kötznen
See. Bertil Stronberg
Application Number:
JP11274296A
Publication Date:
August 17, 2005
Filing Date:
May 07, 1996
Export Citation:
Assignee:
Andritz Incorporated
International Classes:
D21D5/00; D21C1/06; D21C3/26; D21D5/28; (IPC1-7): D21C3/26; D21C1/06
Domestic Patent References:
| JP3040886A | ||||
| JP2216289A | ||||
| JP50142801A | ||||
| JP46002951A | ||||
| JP5145681B2 | ||||
| JP317052B1 | ||||
| JP3930281Y1 |
Attorney, Agent or Firm:
Shizuo Nakamura