发明名称 |
CONTINUOUS COOKING WITH COOL IMPREGNATION AND DOM CONTROL |
摘要 |
A method of treating wood chips allows chemical pulp (e.g. kraft pulp) to be produced having enhanced fiber strength properties. In a first zone or stage the chips are cool impregnated (e.g. at a temperature of about 60-120 DEG C) with a first alkali-containing liquid (25-35 g/l expressed as NaOH). In the top of a continuous digester (13) in a second zone or stage (between the screen assemblies 17, 25) the chips are then treated with a second alkali-containing liquid having an alkali concentration at least 5 g/l less than the first liquid (e.g. 10-20 g/l) and a temperature of between about 120-160 DEG C (e.g. 130-150 DEG C). An extraction (25) typically takes place to effect the change in treatment zones. After the second zone the chips are cooked in a cooking zone or stage (32) at about 140-180 DEG C (e.g. 150-170 DEG C), and at a higher temperature than in the second zone.
|
申请公布号 |
WO9907936(A1) |
申请公布日期 |
1999.02.18 |
申请号 |
WO1998US16038 |
申请日期 |
1998.08.03 |
申请人 |
AHLSTROM MACHINERY, INC. |
发明人 |
STROMBERG, C., BERTIL;PROUGH, J., ROBERT;HENRICSON, KAJ, O.;MARCOCCIA, BRUNO, S. |
分类号 |
D21C1/06;D21C3/02;D21C3/24;(IPC1-7):D21C3/24 |
主分类号 |
D21C1/06 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|