Intensified Flexible Distillation Process for Multi-Period Operation

Abstract

Canada’s aspirations towards an energy independent future mean that it can ill-afford to rest while the rest of the world pursues sustainable energy technologies and other efficient means of energy and chemical fuels production. Fortunately, the abundance of biomass—a sustainable energy resource—within Canada’s borders provides a great opportunity for those seeking to help mitigate the threat of fossil fuel induced climate change to intervene; by taking advantage of this abundant resource and using it in new and improved energy and chemicals production pathways. Our current work, therefore, derives from this notion; and in it, our objective is: the development, design, and optimization of a novel separation process for producing high purity—chemical grade—Methanol (MeOH) and Dimethyl Ether (DME) from biomass-derived syngas.Approaches surveyed often focus on designs of entirely new pieces of equipment, but our work is a take on subtly but critically improving one of the oldest and most ubiquitous pieces of process equipment: tray distillation columns. Using a novel approach for solving the optimization problem, an algorithm is furnished and this is implemented in Matlab, while all process simulations are performed in Aspen Plus. The development of a rigorous framework for designing intensified flexible distillation process for high purity DME-MeOH production is one main contribution of this work. Another major finding is that an intensified flexible process design for DME-MeOH separation for multi-period operation has lower total annualized cost compared the conventional processes. Furthermore, the proposed process shows a lower penalty for being flexible whencompared with the status quo. Although further studies on the effects of process dynamic behaviour, including on transitions and other transient characteristics, are needed, the findings so far suggest a potential for substantial life-time cost savings in new process designs for DME-MeOH separations.