BERG, A.; FUENTEALBA, C.; SALAZAR, J.:
Proceeding 17th International Symposium on Wood, Fibre and Pulping Chemistry ISWFPC 2013 Vancouver, 12-14 de junio 2013.
The possibility of separating cellulose, lignin and hemicelluloses in an acetic media has been known for several decades: There are numerous studies in the laboratory and, in turn, a pilot plant in southern Germany was implemented in the late 80s for pine wood processing, and in northern France a few years ago for wheat straw.
This presentation shows the results at the pilot level of a discontinuous process that operates in the Technological Development Unit from the Universidad de Concepción in Chile and consists of a 800 l pressurized digester, and a pulp closed washing system with organic solvents, based on three consecutive stages of dilution-pressing. Comparative results are presented when processing softwood (Pinus radiata D. Don), hardwood (Eucalyptus globulus) and agricultural residues (wheat straw). The main difference between the three materials is the optimum digestion temperature. In case of wheat straw, it is possible to operate at normal pressure, adding formic acid to the solution.
The digestion of wheat straw was carried out processing a total of 600 kg of raw material. The wheat straw pulp was used to produce paper in a commercial machine, dissolved carbohydrates were used as a replacement for molasses in dairy cow feeding and lignin was applied as a wood adhesive component.
The technical results of the process, the characterization of lignocellulosic components and applications for the products are reported.