Hemicellulose recovery and purification from TMP mill wastewaters

近年来，由于全球竞争和对纸产品需求的减少，北美的森林产品行业面临着重大挑战。据信，北美的纸浆和造纸（PP）工业必须结合生物精炼工艺或在现有的PP米尔斯厂中创建新的部分，以除了传统的PP产品之外，还生产增值化学品和生物能源，以在全球范围内竞争。目前，在Resolute Forest Products Inc.在雷霆湾操作中，2-5%的木材材料，包括半纤维素、木质素和提取物，作为胶体颗粒溶解或分散到工艺沃茨中。传统上，溶解在废水流中的有机分子被认为是“废物”，需要进一步处理。例如，大多数废物流用作PP米尔斯厂的低热值源（硫酸盐米尔斯厂中的黑液）或以废水流排放用于能量密集型需氧生物处理。PP废水流和污泥中单个有机分子的真实值和势能尚未被探索和利用。本研究将探讨先进膜分离技术从TMP废水中回收和纯化半纤维素的可行性，以生产增值产品，减少废水处理厂的有机负荷，节省运营成本。预计将为综合森林生物精炼开发新的分离技术（膜分离），其效率是目前技术无法实现的。

The forest products industry in North America has faced significant challenges in recent years, due to global competition and reduced demand for paper products. It is believed that the pulp and paper (PP) industry in North America has to incorporate biorefining processes or create a new segment in the existing PP mills to make value-added chemicals and bioenergy, in addition to the traditional PP products, to compete globally. Currently, in the thermo-mechanical pulping (TMP) process of Resolute Forest Products Inc. Thunder Bay Operation, 2-5% of the wood materials, which includes hemicelluloses, lignin and extractives, are dissolved or dispersed as colloidal particles into process waters. Traditionally, the organic molecules dissolved in the wastewater streams are considered as "wastes" and need further treatment. For example, most of waste streams are used as low heat value sources to the PP mills (black liquor in kraft mills) or discharged in wastewater streams for energy intensive aerobic biological treatment. The true values and potential energy of the individual organic molecules in the PP wastewater streams and sludge have not been explored and utilized. The proposed study will investigate the feasibility of advanced membrane separation technology for hemicellulose recovery and purification from a TMP mill wastewater to produce a value-added product and reduce the organic loading to the wastewater treatment plant and save operating cost. It is anticipated that novel separation technology (membrane separations) will be developed for integrated forest biorefinery with efficiency that is not achievable with current technologies.