A Process Intensification synthesis framework for the design of dividing wall column systems

In this work, we present a process intensification synthesis approach for the design of dividing wall columns based on the Generalized Modular Representation Framework. A superstructure-based representation is developed to represent chemical process alternatives leveraging modular phenomenological building blocks (i.e., pure heat exchange module, mass/heat exchange module). Novel process structures, including but not limited to dividing wall columns, can be systematically generated to enhance process cost and/or energy performance without pre-postulation of equipment design. To describe the possible liquid-vapor and liquid-liquid phase behaviors of the multi-component mixture, rigorous physical property calculations (e.g., UNIQUAC) are explicitly incorporated. The synthesis model is formulated as a single mixed-integer nonlinear optimization problem. The applicability and versatility of the proposed framework is showcased via an industrial case study on methyl methacrylate purification by Dow Global Technologies. Two new dividing wall column designs are obtained, both of which can achieve equipment size reduction and substantial energy savings compared to the original patent design.