Comparative Study of Biomass Extraction from the Hydrolyzate of Wood Hydrothermal Btreatment, Using Polyethyleneimine and Aluminium Salts

Plywood is one of the main exported products of Latvia's woodworking industry. The hydrothermal treatment of wood is the first stage before its mechanical processing. During this treatment, autohydrolysis of wood takes place, involving the cleavage of hydrolyzable bonds in lignin and polysaccharides. As a result, the wastewater of a basin of wood hydrothermal treatment is dramatically polluted with low molecular lignin, hemicelulose fragments and wood extractives, which all together may be called as waste wood biomass (WWB). Keeping in mind the zero waste policy for rational use of bioresources and the possible usage of waste wood originated matter in practice [1-3], it is very important to extract quantitatively the formed biomass from the basin's wastewater, with the following qualitative removal of the formed sludge. The aim of the study was to compare the effectiveness of biomass extraction from the model wastewater of the wood hydrothermal treatment, using separately polymer cation and inorganic salts as coagulant