Back to results
US 2026/0193838 A1Published application
Method for bleaching cellulose pulp formed from recycled textile material
AssigneeValmet Corporation
InventorsMaria VENNERSTRÖM, Ann-Sofi NÄSHOLM, Sofia BYLUND
Life of this patent
Estimating the term…
Abstract
A method for bleaching pulp formed from recycled textile material comprising cellulose The method comprises subjecting the pulp to at least Pulp formed from one bleaching stage (2), after a final bleaching stage of said at least one bleaching stage, washing (3) the pulp, and after said washing, acidifying (4) the pulp.
Claims13
A method for bleaching pulp formed from recycled textile material comprising cellulose, said method comprising:
- subjecting the pulp to at least one bleaching stage;
- and
- after a final bleaching stage of said at least one bleaching stage, washing and acidifying the pulp, wherein:
- said final bleaching stage comprises hydrogen peroxide bleaching, the method further comprising, prior to or during said hydrogen peroxide bleaching, adding magnesium sulfate, and
- said acidifying is carried out by:
- adding at least one acidifying chemical during the washing, and
- an acidifying stage after said washing, the acidifying stage comprising adding at least one acidifying chemical.
4 more elements
A system for producing bleached cellulose pulp from recycled textile material comprising cellulose, said system comprising:
- a pulping arrangement arranged to receive the recycled textile material to produce pulp therefrom;
- at least one bleaching arrangement arranged to bleach pulp obtained from the pulping arrangement, wherein a final bleaching arrangement of said at least one bleaching arrangement is configured for hydrogen peroxide bleaching;
- means for adding magnesium sulfate to, or prior to, said final bleaching arrangement;
- a washing arrangement arranged to wash bleached pulp from said final bleaching arrangement;
- means for adding at least one acidifying chemical to said washing arrangement;
- and
- an acidifying arrangement arranged to acidify the pulp from the washing arrangement.
4 more elements
Dependencies are inferred from the claim text.