Implementation of biorefining technologies in Kraft mills: impact assessment and feasibility

牛皮纸工艺生产的木浆用于制造高质量的印刷纸、薄纸和包装材料。这是一个有吸引力的候选人，部分转化为生物炼制，同时保持其传统的核心产品的生产。森林生物精炼厂的前提是，溶解在废液中的化学制浆步骤的副产品木材的一些有机成分可以用于比现场燃烧以恢复其打浆价值更大的优势，如目前所做的那样;它们可以用作制造具有显著市场价值的各种产品的原料。然而，将卡夫食品厂改造为生物精炼厂将大大改变其可持续能源生产的能力。本项目建议制定一种方法和标准，以评估加拿大硫酸盐米尔斯生物精炼厂的技术经济可行性。从高度集成和节能的卡夫米尔斯的基本情况下，我们将应用最先进的模拟技术和系统工程工具，以检查关键生物精炼技术的能量平衡和运行成本的过程中的影响。它们是木质素沉淀、半纤维素提取和生物质气化。将开发一种先进的能源效率分析新方法，并将其应用于研究。它将考虑到单独和共同影响能源消耗的因素：内部能源回收、使用蒸汽注入和混合、水系统关闭、供热和发电以及采用能源升级技术（热电联产和三联发电、吸收式热泵）。经济可行性将通过一种新的热经济分析方法进行评估。将确定生物精炼技术对工艺废气排放的影响。该项目的主要成果将是指导方针，可用于审查拟议的生物精炼概念的可行性，指导对这些技术的投资，并帮助制定解决技术障碍的研究战略。生物炼制单元操作模型和纸浆厂为基础的生物炼制独特的工艺模拟软件将产生和验证。

The Kraft process produces wood pulp for the manufacture of high quality printing papers, tissue papers and packaging material. It is an attractive candidate for partial conversion to biorefinery while maintaining the manufacturing of its traditional core products. The premise of the forest biorefinery is that some of the organic constituents of the wood which are by-products of the chemical pulping step dissolved in the spent liquor may be used for greater advantage than being burnt on-site to recover their beating value as is currently done; they could be used as feedstock for the manufacture of a broad variety of products which have a significant market value. However, the conversion of a Kraft mill to a biorefinery will profoundly modify its capacity for sustainable energy production. This project proposes to develop a methodology and criteria to evaluate the techno-economic feasibility of biorefinery options for Canadian Kraft mills. Starting from the base-case of highly integrated and energy efficient Kraft mills, we will apply state-of-the-art simulation techniques and systems engineering tools to examine the effects of key biorefinery technologies on the energy balance and operating cost of the process. They are, lignin precipitation, hemicelluloses extraction and biomass gasification. A new methodology for advanced energy efficiency analysis will be developed and applied to the study. It will take into account the factors that affect energy consumption individually and in conjunction: internal energy recovery, use of steam injection and mixing, water systems closure, heat and power production and the incorporation of energy upgrading technologies (co- and tri-generation, absorption heat pumps). Economic viability will be assessed by a new thermo-economic analysis method. The impacts of biorefining technologies on the process air emissions will be determined. The major outcome of this project will be guidelines that can be applied to examine the feasibility of proposed biorefinery concepts, guide investments in these technologies and help develop research strategies that address technical impediments. Models of biorefinery unit operations and a unique process simulation software for pulp mill-based biorefineries will be produced and validated.