Fundamental characterization and enhancement of chemical engineering processes using advanced optimal control techniques

该研究计划的重点是应用最优控制的原理和技术来确定基本的传输特性，并提高化学工程过程的性能。提出的目标是：(i)确定聚合物和重油中各种气相溶剂的未知和急需的浓度依赖的多组分扩散系数；（ii）研究稠油采收率的提高——同时使用最优控制的原理和技术。第一个目标涉及分别在工业相关聚合物和重油中对气体混合物（如二氧化碳和氮气）和气相溶剂（如蒸汽和丙烷）的浓度依赖、多组分扩散系数的实验测定。了解多组分扩散系数对于提高聚合物的生产和加工以及稠油的采收率至关重要。然而，人们对多组分扩散的认识很少，实验的多组分扩散率数据也很少。这一目标下的研究将通过实验确定与工业相关的各种温度和压力条件下聚合物和重油中气相混合物的浓度依赖扩散率，从而提供急需的知识。除了确定多组分扩散外，本研究的显著特征是使用最优控制技术捕获浓度依赖性。这一结果将使聚合物和重油领域的工程师能够确定涉及多组分扩散的各自工艺的最佳操作条件。第二个目标涉及应用最优控制来提高稠油采收率，并随后通过实验室规模实验进行验证。加拿大的重油储量约占世界现有石油储量的一半，在轻油储量不断减少的情况下，加拿大的重油储量完全能够满足世界对石油产品的需求。然而，由于稠油本身的高粘度，稠油的提取并不容易。提取需要复杂的回收方法，需要加强。为此，我们将利用最优控制来确定溶剂注入压力和时间策略，以提高蒸汽萃取（Vapex）的石油产量，与传统的热工艺相比，蒸汽萃取是一种非常环保的工艺。我们最初的实验室测试结果非常令人鼓舞。他们的石油产量增加了35%。为了有条不紊地实现这种强化，我们将制定并解决最优控制问题，以确定最大限度地提高石油产量的注入政策。在实验中实施最优策略，以验证和交叉检查石油产量。还将考虑诸如减少能源成本和水消耗等其他目标。值得注意的是，拟议的研究计划在应用最优控制方面是新颖和创新的，这将使传输特性的细粒度捕获成为可能，并为过程增强提供了广阔的空间。这项研究的结果将为多组分运输提供更深入的见解，并为更具成本效益和环保的重油开采开辟新的途径。最后但并非最不重要的是，拟议的研究项目将通过积极参与硕士和博士研究生，为培养高素质人才提供一个很好的平台。他们将学习并将最佳控制技术应用于实际目的，并在毕业后提高加拿大工业的高技能劳动力能力。

The focus of the research program is to apply the principles and techniques of optimal control to determine the fundamental transport properties and to enhance the performance of chemical engineering processes. The proposed objectives are: (i) to determine the unknown and much-needed concentration-dependent, multi-component diffusivities of various gas-phase solvents in polymers and heavy oils; and (ii) to investigate the enhancement of heavy oil recovery --- both using the principles and techniques of optimal control. The first objective involves the experimental determination of concentration-dependent, multi-component diffusivities of gas mixtures (e.g. carbon dioxide and nitrogen) and gas-phase solvents (e.g. steam and propane) in, respectively, industrially relevant polymers and heavy oil. The knowledge of multi-component diffusivities is vital for the enhancement of polymer production and processing, and the recovery of heavy oil. However, the understanding of multi-component diffusion is little, and the experimental multi-component diffusivity data are scarce. Research under this objective will furnish that much-needed knowledge by experimentally determining the concentration-dependent diffusivities of gas-phase mixtures in polymers and heavy oil at various temperature and pressure conditions of industrial relevance. In addition to the determination of multi-component diffusion, the salient feature of this research is the capture of concentration-dependence using the techniques of Optimal Control. This outcome will enable engineers in the polymer as well as heavy oil sector ascertain the best operating conditions for respective processes involving multi-component diffusion. The second objective involves the application of Optimal Control for enhancement of heavy oil recovery and subsequent validation using laboratory scale experimentation. Being about half of the estimated oil-in-place world over, the Canadian heavy oil reserves are more than capable of meeting the world demand of petroleum products in the face of diminishing light oil reserves. However, the extraction of heavy oil is not easy due to its high native viscosities. The extraction requires sophisticated recovery methods, which need to be intensified. For this purpose, we will utilize Optimal Control to determine solvent injection pressure versus time policies that intensify oil production in Vapor extraction (Vapex), which is a very environmental-friendly process in contrast to the conventional thermal processes. Our initial laboratory tests have been very encouraging. They have registered up to 35% increase in oil production. To realize such intensification methodically, we will formulate and solve the optimal control problem to determine the injection policy that maximizes oil production. The optimal policy will be implemented in experiments to validate and cross-check the oil production. Additional objectives such as reducing energy costs and water consumption will also be considered. It is important to note that the proposed research program is novel and innovative in applying Optimal Control, which will enable a fine-grained capture of transport properties and unleash a vast scope for process enhancement. The results from this research will provide deeper insights into multi-component transport and open new avenues for more cost effective and environmentally friendly recovery of heavy oil. Last but not least, the proposed research program will provide an excellent platform for the training of highly qualified personnel by actively involving master's and doctorate students. They will learn and apply optimal control techniques to practical ends and, upon graduation, enhance the highly-skilled work force capacity of the Canadian industry.