Wood Biomass from the Model Wastewater and Its Fractionation

Abstract

The production of veneer in Latvia and many countries of East Europe is accomplished by the hydrothermal treatment of hardwood in special water basins. As a result, formed effluents contain wood-originated pollutants, which are responsible for the enhanced chemical oxygen demand and the intensive colour of the wastewater. Keeping in mind the volume of the polluted effluents formed annually at the Latvian plywood plants, it is very important to extract qualitatively and quantitatively the formed biomass from the effluent. The choose of an effective method of the waste biomass extraction depends on chemical characterisation of the effluent. In this work, for imitating woodworking wastewater, birch sawdust was hydrothermally treated in mild alkaline conditions at 90 o C. The yield of the solid biomass did not exceed 7% and contained, mainly, hemicelluloses in the polysaccharide form and lignin. The applied instrumental analysis (FTIR-, UV-, Raman spectroscopy) testify the dominant content of hemicelluloses in the obtained biomass. The fractionation of the biomass was performed using concentrated sulphuric acid and ethanol. As the obtained results have shown, the content of lignin, hemicelluloses and water-soluble degraded wood products in the solid biomass corresponded to the following mass ratio: 1.2 /6.7 /1.0, respectively.

New Environmentally Friendly Dust Suppressant Based on Lignocellulosic Biomass From Wood Processing Wastewater

“…The previous studies [18] of the component composition of the biomass with instrumental analysis (FTIR-, UV-, Raman spectroscopy; HPLC) indicated that the dominant wood component in the obtained biomass were hemicelluloses, and the content of hemicelluloses, lignin and water-soluble degraded wood products in the biomass corresponded to the following mass ratio: 6.7/1.2/1.0, respectively.…”

“…The hydrothermal treatment of sawdust was performed with 0.01M NaOH at a 1/50 (mass ratio of the oven dry sawdust to water) hydromodulus and a temperature of 90°C for 4 h. After hydrolysis, the hydrolyzate was separated from the sawdust treated through filtration. The model solution characterization has been published in our previous work [18].…”

Characteristics of the Coagulate Obtained During the Process of Model Wastewater Treatment

“…A hydrolysis was fulfilled in an alkaline water environment, at the water duty of 1/50, the temperature 90 °C and the duration was about 4 hours. The model wastewater was described by HLES content, COD, BOD 5 and its color [11,12].…”