(58c) Design of Heat-Integrated Pressure Swing Distillation Process Using a Graphical Pinch Analysis

Based on a graphical pinch analysis, a method for the fundamental design and heat integration of pressure swing distillation (PSD) is demonstrated. The pinch pressure, determined by the graphical pinch analysis, serves as a minimum pressure constraint that enables the provision of the required temperature driving force for heat integration and bypass of distillation boundaries. To evaluate the feasibility of heat-integrated pressure swing distillation (HIPSD), the proposed method necessitates the visualization of feasible composition regions for initial feed compositions and pinch temperature contour lines, considering pressure changes and the dynamic characteristics of a three-component mixture. Therefore, in this study, an in-depth investigation was conducted through three case studies to demonstrate heat integration in the HIPSD. The HIPSD system can have different pinch pressures depending on the distillation column arrangement or the separation sequence of products. Furthermore, considering pinch constraints, the proposed analysis method allows for the design of energy-efficient HIPSD processes by determining the optimal operating pressure of the columns.