Patent ID: 6641699
Filing Date: 2003-11-04
Classification: D21B,D21C,Y10S

Abstract:
A chemical wood pulping process having reduced volatile organic compound emissions, the process comprising:(a) extracting wood particulates with solvent at a pressure less than 50 psi to reduce naturally-occurring particulate pitch and volatile organic compound content without significant dissolution of lignin and wood cellulosic components, the solvent recycled for reuse in extraction of wood extractives, said solvent being selected from the group consisting of methanol, ethanol and acetone; (b) commingling the extracted wood particulates with a liquor comprising chemical reactants, not including the solvent used to extract the wood particulates, for solubilizing lignin contained in the wood particulates; (c) allowing the chemical reactants of the liquor to react with lignin contained in the extracted wood particulates under controlled conditions of temperature and pressure for a time sufficient to solubilize and remove lignin from the wood particulates; and (d) producing a wood pulp comprising individual cellulosic fibers while releasing a reduced amount of VOCs in the wood pulping process, as compared to a chemical wood pulping process selecting wood particulates containing naturally-occurring levels of VOCs.