A Call for a Different Plant Modelling Paradigm and a New Generation of Software

Abstract

This paper is an invitation to change the plant modeling paradigm to achieve much easier convergence and ensure model consistency between different incarnations of the plant model, while retaining accuracy on par with the rigorous models. Rigorous physical properties [property/mole] are replaced by [property/mass] approximation at local conditions, making bulk properties much less sensitive to changes in stream composition. This eliminates the need for stream mole fractions and stream compositions can be described by linear component mass flows. Detailed process flow diagram is a common topology for all models. Different incarnations of node models are employed at different levels of abstraction (planning, scheduling, optimization, control, design), ensuring inheritance, consistency and increasing accuracy of solutions as plant model instances move from mass to mass-energy, to mass-energy-and-approximate-stream-properties. After the plant model with approximate properties is solved, they are updated via rigorous thermodynamic methods and the plant model is resolved until convergence.