GOALI:Catalyst Deactivation and Heat Transfer Modelling for Fixed Bed Reactors Using Computational Fluid Dynamics

GOALI：使用计算流体动力学对固定床反应器进行催化剂失活和传热建模

• 批准号: 0625693
• 负责人: Anthony Dixon
• 金额: --
• 依托单位: Worcester Polytechnic Institute
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-10-01 至 2011-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0625693&HistoricalAwards=false
• 关键词: GOALI; Catalyst; Deactivation; Heat; Transfer

ABSTRACTPI: Anthony G. Dixon and Hugh Stitt Institution: Worcester Polytechnic InstituteProposal Number: 0625693Title: GOALI: Catalyst Deactivation and Heat Transfer Modelling for Fixed Bed Reactors Using Computational Fluid DynamicsToday's increasing environmental and economic pressures on the chemical industry have resulted in a continuing push towards more efficient processing in chemical reactors, by increasing conversion and selectivity, and by managing the energy requirements of the process effectively. The key to accomplishing these goals is improving understanding of the physical and chemical processes taking place within chemical reactors, upon which correct design and operation are based. Catalytic tubular fixed bed reactors are widely used for large-scale, heterogeneously-catalyzed gas-phase reactions, such as steam reforming. These reactors have large heat effects, especially near the tube wall, where strong temperature gradients exist. For analysis and scale-up, modeling and simulation are essential tools. Existing models, however, have been found to be inadequate, and do not allow reliable priori design. The main reason that the current models are not good enough is that they are based on intuitive simplifications, with the model parameters being fitted to specific conditions.The intellectual merit of this project is that a systematic approach to fixed bed reactor modeling is will be undertaken using first principles to understand the effects of tube wall heat transfer and of catalyst particle design on reactor performance. Building on previous work by the Principal Investigators, a methodology will be developed to improve one's ability to predict radial temperature profiles in catalyst tubes, and to assess the impact of heat transfer on catalyst performance. Computational fluid dynamics (CFD) will be used to simulate fluid flow patterns and temperature fields around the catalyst, to capture the effects of changes in the catalyst particle shapes and features. This will be coupled with transport and reaction inside the solid catalyst particles, with emphasis on the effects on catalyst deactivation through coking. The result of this coupled approach will be that deactivation rates inside the reactor tubes will be evaluated under the correct conditions, especially in the near-wall region, giving much improved predictive capability. A feature of the work will be the collaborative effort between industry and academia, allowing extensive validation of the computer simulations by comparison to data taken directly from industrial pilot plants, and ensuring that the practical, industrial perspective informs the work at all stages.The broader impact of this work lies in the benefits to society of improved methods for carrying out catalytic reactions, and in education and infrastructure development. Johnson Matthey is a major supplier and innovator in catalyst development. The improved understanding of the interaction between heat transfer and catalyst deactivation that will result from this collaborative work will increase catalyst and reactor tube life, thus having positive consequences for sustainable engineering. Of particular importance for the future is hydrogen production, and efficient use must be made of the abundant reserves of natural gas, using conversion technologies such as steam reforming, the focus of this project. It is also important that the students who are educated in reaction engineering are exposed to modern computational tools. Both undergraduate and graduate students will be involved in this research. The project results will be disseminated broadly, through industrial use and interdisciplinary conferences.

摘要：安东尼·G.狄克逊和休斯蒂特机构：伍斯特理工学院提案编号：0625693标题：目标：使用计算流体动力学的固定床反应器的催化剂失活和传热建模当今对化学工业日益增加的环境和经济压力导致了对化学反应器中更有效处理的持续推动，通过增加转化率和选择性，以及通过有效地管理工艺的能量需求。 实现这些目标的关键是提高对化学反应器内发生的物理和化学过程的理解，这是正确设计和操作的基础。催化管式固定床反应器广泛用于大规模的非均相催化气相反应，例如蒸汽重整。 这些反应器具有很大的热效应，特别是在管壁附近，那里存在很强的温度梯度。 对于分析和放大，建模和仿真是必不可少的工具。 然而，现有的模型，已被发现是不够的，不允许可靠的先验设计。目前的模型不够好的主要原因是，它们是基于直观的简化，与模型参数被拟合到特定的condition.The智力的优点是，该项目的固定床反应器建模的系统方法是将进行使用第一原理，以了解管壁传热和催化剂颗粒设计对反应器性能的影响。 在主要研究人员以前工作的基础上，将开发一种方法，以提高预测催化剂管中径向温度分布的能力，并评估传热对催化剂性能的影响。 计算流体动力学（CFD）将用于模拟催化剂周围的流体流动模式和温度场，以捕捉催化剂颗粒形状和特征变化的影响。 这将与固体催化剂颗粒内部的传输和反应相结合，重点是通过焦化对催化剂失活的影响。 这种耦合方法的结果将是反应器管内的失活速率将在正确的条件下进行评估，特别是在近壁区域，从而大大提高了预测能力。 这项工作的一个特点是工业界和学术界之间的合作努力，通过与直接从工业试验工厂获得的数据进行比较，允许对计算机模拟进行广泛的验证，并确保在所有阶段都能从实用的工业角度指导工作。这项工作的更广泛影响在于改进催化反应的方法，以及教育和基础设施建设。 约翰逊万丰是催化剂开发领域的主要供应商和创新者。 通过这种合作，对传热和催化剂失活之间相互作用的理解得到了提高，这将延长催化剂和反应器管的寿命，从而对可持续工程产生积极影响。 对未来特别重要的是制氢，必须利用该项目的重点-蒸汽重整等转化技术，有效利用丰富的天然气储量。 同样重要的是，在反应工程教育的学生接触到现代计算工具。本科生和研究生都将参与这项研究。项目成果将通过工业用途和跨学科会议广泛传播。