Liquid Fuel Reformation in Direct Droplet Impingement Microreactors

该奖项由2009年美国复苏和再投资法案(公法111-5)资助。目标和方法应用于化学处理通常需要在固体催化剂存在下蒸发液体试剂、混合和多相反应，然后进行产品分离。在传统的大型化学反应器中，每个过程通常在专用部件中进行，针对其给定的功能进行优化，并连接在一起形成整个系统。这些大型化工厂的缩小版已被考虑用于分布式应用，特别是从碳氢化合物液体原料生产氢气，但基于单独单元操作方法的反应器设计已被证明很快变得次优，特别是对于空间有限的应用。为了应对反应堆小型化的挑战，出现了多功能反应堆的概念，其中探索了不同单元操作的协同组合以实现性能的改善。直接液滴撞击反应器(DDIR)是一种以非常高的速率对高能量密度液体燃料进行多功能化学处理的新概念，使高密度功率转换技术的发展成为可能。这个项目的重点是建立对DDIR反应堆中燃料输送、蒸发和反应之间复杂相互作用的基本理解，从而为这类新型反应堆的优化设计和操作提供一种经过实验验证的方法。预计拟议的研究将产生以下贡献：(1)理论分析和模拟将产生DDIR设计图(S)，该设计图允许以转化率和选择性作为性能指标来确定最佳运行点；(2)从理论上推导的最优设计图(S)将得到实验验证，展示了DDIR反应器性能的预测趋势。实验验证将有助于建立将发展到其他反应系统的一般理论框架扩展到一定程度的置信度；以及(3)将通过实验和模拟对DDIR反应器的强制非稳态操作进行探索性研究。据推测，通过改变这些强制时间尺度相对于系统的自然时间尺度，可能会导致时间平均反应堆性能的改善。广泛的影响如果成功，这项研究将为社会带来显著的好处，潜在地为广泛的工程应用带来变革的好处，包括开发一种新的反应堆技术，用于便携式和分布式发电，以及对包括可再生能源在内的多种液体燃料进行高效的化学处理。这项研究将通过将研究成果整合到几门学术课程中并通过本科生的研究机会来促进发现和理解，同时促进教学、培训和学习。扩大代表性不足群体的参与将通过吸纳代表性不足群体的研究生和本科生来实现，其中包括HBMU：克拉克·亚特兰大学院、斯佩尔曼学院和莫尔豪斯学院的毕业生。这项工作将通过在PI的机构开发和维护MEMS制造和表征设施来加强研究和教育的基础设施。将通过几项活动进行广泛传播，以增进对科学技术的了解。首先，将促进业界的积极参与，使研究成果能够转化为行业实践。其次，研究成果将通过技术论文和在工程论坛上的陈述以及国际工程学会为当地高中生组织的特别活动来传播。

0928716FedorovThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Objectives and Methods to be EmployedChemical processing frequently requires vaporizing liquid reagents, mixing, and heterogeneous reaction in the presence of a solid catalyst, followed by product separation. In traditional large scale chemical reactors each process is typically carried out in dedicated components, optimized for their given function, and linked together to form the overall system. Scaled down versions of these large-scale chemical plants have been considered for distributed applications, in particular hydrogen generation from hydrocarbon liquid feedstock, but the reactor design based on the individual unit operation approach has been shown to quickly become sub-optimal especially for space-constrained applications. To address this challenge of reactor scale-down, the concept of multifunctional reactors has emerged, in which synergistic combination of different unit operations is explored to achieve improved performance.The Direct Droplet Impingement Reactor (DDIR) is a new concept for multifunctional chemical processing of high energy density liquid fuels at very high rate, enabling development of high density power conversion technologies. This project focuses on establishing fundamental understanding of the complex interplay between the fuel delivery, evaporation, and reaction in DDIR reactors, resulting in an experimentally-validated methodology for optimal design and operation of this new class of reactors.Intellectual MeritNew theoretical and experimental tools will be developed to carry out a comprehensive study of the DDIR reactor concept. The following contributions are expected to result from the proposed investigation: (1) Theoretical analysis and simulations will yield the DDIR design map(s) that allow determination of optimal operating points using conversion rates and selectivity as performance metrics; (2) Theoretically-derived optimal design map(s) will be experimentally validated, demonstrating the predicted trends in DDIR reactor performance. The experimental validation will be instrumental in establishing a degree of confidence in extending the general theoretical framework developed to other reacting systems; and (3) Exploratory studies of the forced unsteady-state operation of the DDIR reactor will be undertaken, via experiments and simulations. It is conjectured that by changing these forcing time scales relative to the natural time scales of the system, improvements in time-averaged reactor performance may result.Broader ImpactsIf successful, this research could provide a significant benefit to society with potentiallytransformational benefits to a wide range of engineering applications, including development of a new reactor technology for portable and distributed power generation and efficient chemical processing for a broad range of liquid fuels, including renewable energy sources. This research will advance discovery and understanding while promoting teaching, training, and learning by incorporating the research results into several academic courses and through undergraduate research opportunities. Broadening of participation by underrepresented groups will be achieved by engaging graduate and undergraduate students from under-represented groups, including graduates of HBMUs: Clark Atlanta, Spellman, and Morehouse Colleges. The work will enhance the infrastructure for research and education by developing and maintaining facilities for MEMS fabrication and characterization at the PI's institution. Broad dissemination to enhance scientific and technological understanding will be achieved through several activities. First, active industry involvement will be facilitated to enable the transfer of research results into industry practice. Second, research results will be disseminated through technical papers and presentations in engineering forums, as well as special events that the PI will organize for local high school students.