VALOIR: Value added lignins as renewable raw materials dedicated to the end-users requirements out of black liquor from existing pulp mills

• Research unit: EU RFP
• Project number: 97.0304-2

Key words (English)

Lignin; black liquor; dispersant; surfactant; cementitious material

Alternative project number (English)

EU project number: FAIR-CT98-3521

Research programs (English)

EU-programme: 4. Frame Research Programme - 4.3 Biomedical/Health research

Short description (English)

See abstract

Partners and International Organizations (English)

Coordinator: ATO-DLO (NL)

Abstract (English)

The production of cellulose fibers from annual plants/crops is accompanied by a significant amount of processing waste products (known as black liquors). The target of the VALOIR project is to reach a valorisation of such side products.
The joint investigations of this project were carried out by Granit S.A. and 'Holderbank'. Granit was responsible for the modification of the black liquors and 'Holderbank' responsible for the testing of ap-plications in the construction industry, especially in cementitious materials.
Black liquor is a renewable, non-hazardous raw material that opens a potential for the production of environmentally friendly construction materials.
In the first project phase, the black liquors were refined by the new process. Granit S.A. developed this process, which is a selective oxidation, and has in the meantime been granted an European Patent (EP 970275A). After such treatment of the black liquor, the lignins were chemically modified to polymers with dispersing characteristics.
The investigation of our activity was focused on the application of such materials for the production of cementitious materials. In a first assessment, the dispersing effects of different modified lignins were tested to optimise the selective oxidation process. Received samples were tested in mortars prepared according to test method EN 196 (SIA 215.001). Most promising lignins were selected and formulated by the addition of required anti-foaming agents. After that screening the optimised admixtures were selected for further testing.
As next step the application of the modified lignins will be tested as processing additions in the cement production process. In this evaluation the economical benefits expressed in cost/efficiency-ratio, will be compared with other, preferably renewable, commercial products.

References in databases (English)

Swiss Database: Euro-DB of the
State Secretariat for Education and Research
Hallwylstrasse 4
CH-3003 Berne, Switzerland
Tel. [phone]
Swiss Project-Number: 97.0304-2