Reaction engineering and mixing in pulp and paper processes

化学纸浆生产是加拿大的一个主要资源型产业，继续与日益激烈的全球竞争、波动的加元和老化的基础设施作斗争。为了提高行业的竞争地位，必须实现制浆工艺的改进和创新，并降低制造成本。本研究提案中描述的项目旨在减少制浆和漂白操作中的化学品使用，提高产品均匀性和质量（创造营销机会和增加产量的可能性），并展望该行业的未来可能性。建议开展三个项目：首先是确定混合过程如何影响纳米晶纤维素（NCC）的生产和性能，NCC正在研究作为纸浆纤维的新型增值产品的来源。混合和反应工程可以影响纳米级产品的生成，并且所提出的工作将在NCC生成和特性的背景下对此进行研究。第二个项目将研究多硫化合物的生产，这是一种化学添加剂，当存在于蒸煮液中时，可以显着提高纸浆产量。我们将开发一个多硫化物生成的反应工程模型（包括相关的传质过程和新的动力学信息）作为反应器设计和优化的工具。这项工作也将扩展到检查现有的纸浆液体氧化过程（特别是白色液体氧化）。最后，我们正在进行的工作，研究宏观尺度混合纸浆悬浮液已经确定了几个值得追求的机会，包括混合和流动在两个工业上重要的混合器配置。在我们的研究小组开发的实验技术将被应用到这些混频器配置。

Chemical pulp production is a major resource-based Canadian industry that continues to struggle with increased global competition, a fluctuating Canadian dollar and aging infrastructure. To improve the competitive position of the industry, improvement and innovation in pulping processes must be achieved and a reduction in manufacturing costs realized. The projects described in this research proposal aim to reduce chemical use in pulping and bleaching operations and improve product uniformity and quality (creating marketing opportunities and the possibility of increased production), as well as look to future possibilities in the industry. Three projects are proposed: The first is to determine how mixing processes impact the production and properties of nanocrystalline cellulose (NCC) which is being studied as a source of novel and value-added products from pulp fibre. Mixing and reaction engineering can influence generation of the nano-scale products, and the work proposed will examine this in the context of NCC generation and properties. The second project will examine the production of polysulfide, a chemical additive shown to markedly improve pulp yield when present in the cooking liquor. We will develop a reaction engineering model for polysulfide generation (which will include relevant mass transfer processes and new kinetic information) as a tool for reactor design and optimization. The work will also be extended to examine existing pulp liquor oxidation processes (particularly white liquor oxidation). Finally, our ongoing work examining macroscale mixing of pulp suspensions has identified several opportunities worth pursuing, including mixing and flow in two industrially important mixer configurations. The experimental techniques developed in our research group will be applied to these mixer configurations.