Invention Grant
- Patent Title: Bleaching process of chemical pulp
- Patent Title (中): 化学纸浆漂白工艺
-
Application No.: US12295378Application Date: 2007-03-27
-
Publication No.: US08524038B2Publication Date: 2013-09-03
- Inventor: Aki Vilpponen , Panu Tikka
- Applicant: Aki Vilpponen , Panu Tikka
- Applicant Address: FI Espoo
- Assignee: Oy Lannen Tutkimus—Western Research Inc.
- Current Assignee: Oy Lannen Tutkimus—Western Research Inc.
- Current Assignee Address: FI Espoo
- Agency: Young & Thompson
- Priority: FI20060314 20060331
- International Application: PCT/FI2007/050168 WO 20070327
- International Announcement: WO2007/113381 WO 20071011
- Main IPC: D21C9/14
- IPC: D21C9/14

Abstract:
A process for the bleaching of chemical pulp, wherein the initial bleaching of the pulp includes a first chlorine dioxide treatment (D0) and a following alkaline treatment with oxygen and hydrogen peroxide (EOP), which stages are separated from each other with a washing stage, and a treatment of the pulp to reduce the content of transition metals of the pulp prior to the peroxide treatment. The process is characterized in that alkali is added to the pulp after addition of chlorine dioxide in the D0 stage to adjust the pH of the pulp to neutral or basic (N stage) prior to the washing stage following the chlorine dioxide stage, whereby the initial bleaching includes the sequence D0N EOP.
Public/Granted literature
- US20090242152A1 BLEACHING PROCESS OF CHEMICAL PULP Public/Granted day:2009-10-01
Information query