Enhancing dissolving pulp production and co-product value

提高溶解浆产量和副产品价值

• 批准号: 516527-2017
• 负责人: Saddler, John
• 金额: $ 6.73万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=692470
• 关键词: Enhancing; dissolving; pulp; production; co

Dissolving pulp is used for manufacturing cellulose derivatives that are used in products such as clothing, cigarette filters, pharmaceuticals, etc. Dissolving pulp is composed of >95% cellulose, thus the hemicellulose and lignin must be removed during the pulping process.Although cellulose purification is an intensive process, the conversion of a Kraft pulp mill to produce dissolving pulp is transformative, as the mill adapts a true biorefinery approach with the potential to generate value from the cellulose, hemicellulose, lignin and extractive biomass components. The critical process modification when converting a conventional Kraft mill to produce dissolving pulp is the prehydrolysis of the wood chips which helps to facilitate the removal of hemicellulose, while subsequent kraft pulping is mostly aimed at removing the lignin. Fortress Specialty Cellulose (FSC) is at the forefront of Canadian efforts to produce dissolving pulp using a pre-hydrolysis Kraft (PHK) pulp feedstock. However, the PHK process presents bottlenecks as it requires extended cooking times and additional digester capacity upstream of kraft pulping. Therefore, methods that can boost hemicellulose removal can increase the overall production rate of a dissolving pulp mill. During prehydrolysis, wood issubjected to treatment under acidic conditions at high temperatures to dissolve the hemicellulose, thus the subsequent transitioning of the acidic prehydrolyzed pulp to the highly alkaline kraft process also presents challenges. As well as these challenges, the PHK process annually produces approximately 40,000 metric tonnes of hemicellulosic sugars. Therefore, valorization of this hemicellulose stream is crucial to the functioning of the mill and creating additional revenues to realize a biorefinery approach. The specific objectives of the proposal can be summarized as follows: 1. To treat wood chips with enzymes to enhance the subsequent removal of hemicellulose during the prehydrolysis process; 2. To integrate green liquor pretreatment during PHK production to reduce pH control issues and enhance cellulose yields and 3.To valorize the hemicellulose produced during pre-hydrolysis through fermentation to "bio-jet" and "drop-in" fuel.

溶解纸浆用于制造用于服装、香烟过滤嘴、药品等产品的纤维素衍生物。溶解纸浆由约95%的纤维素组成，因此在制浆过程中必须去除半纤维素和木质素。虽然纤维素提纯是一个密集的过程，但卡夫纸浆厂生产溶解纸浆的转变是革命性的，因为该工厂采用了真正的生物精炼方法，有可能从纤维素、半纤维素、木质素和提取的生物质成分中产生价值。将传统的硫酸盐纸浆转化为溶解纸浆时，关键的工艺改造是对木屑进行预水解，这有助于去除半纤维素，而随后的硫酸盐纸浆主要是为了去除木质素。堡垒特种纤维素（FSC）是在加拿大的努力，生产溶解纸浆使用预水解硫酸盐（PHK）纸浆原料的最前沿。然而，PHK工艺呈现瓶颈，因为它需要延长蒸煮时间和额外的蒸煮能力上游硫酸盐浆。因此，能够促进半纤维素去除的方法可以提高溶解纸浆厂的整体生产率。在预水解过程中，木材在高温的酸性条件下进行处理，以溶解半纤维素，因此酸性预水解纸浆随后向高碱性硫酸盐工艺过渡也提出了挑战。除了这些挑战，PHK工艺每年生产约40,000公吨半纤维素糖。因此，这种半纤维素流的增值对工厂的运作和创造额外的收入至关重要，以实现生物炼制方法。建议的具体目标可概括如下：用酶处理木屑，提高预水解过程中半纤维素的后续去除；2. 在PHK生产过程中整合绿色液预处理，以减少pH控制问题，提高纤维素收率和3。通过发酵将预水解过程中产生的半纤维素转化为“生物喷射”和“插入式”燃料。