UBC Theses and Dissertations
Fractionation of pulp mill waste to produce hemicellulose oligomers for adsorption onto NBSK pulp Rangu, Varun
Non-renewable fossil fuels and the dangers of climate change have drawn significant research into the forest biorefinery. The pulp and paper industry is positioned to lead the implementation of new technologies from such research. Northern Bleached Softwood Kraft (NBSK) pulp is one of the chief products of the pulp and paper industry in British Columbia (B.C). It is primarily used as reinforcing pulp. Hemicellulose present in mill waste streams such as hog fuel, primary sludge, and chip fines, can be separated and utilized as a strength additive to improve physical strength properties of NBSK pulp, and reduce refining energy. This study investigated the influence of operating variables on the separation of hemicellulose oligomers from these lignocellulosic waste streams, and the adsorption of these oligomers onto NBSK pulp. Reaction temperature and residence time were studied for the separation of hemicellulose, while adsorption temperature, time, fibre consistency, oligomer-to-pulp percentage, and weight average molar mass Mw, were studied for the adsorption of hemicellulose onto NBSK pulp. Hog fuel and primary sludge were found to contain 58.98% and 67.90% polysaccharides respectively. Hemicellulose oligomer yields greater than 90% were obtained from hog fuel via liquid hot water treatment, and from primary sludge via dilute acid hydrolysis. A maximum total oligomer mass of 3.25g was obtained from 25g oven-dry hog fuel. Oligomer-to-pulp percentage and fibre consistency showed a linear effect on the adsorption yield, while adsorption temperature showed a nonlinear effect. The results are encouraging, and suggest the potential of these waste streams to produce a green hemicellulose-based paper strength additive.
Item Citations and Data
Attribution-NonCommercial-NoDerivatives 4.0 International