Towards Distillation Process Supervision using Qualitative Model-Based Reasoning

This paper provides a contribution to Qualitative Reasoning for distillation process supervision. Initial results using a Qualitative Physics to model physical systems have been encouraging, but scaling the approach to realistic problems does not appear as straightforward as initially expected. An approach based on Transfer Function theory is proposed with an application study to a computer simulation of a distillation process. Using a numerical model of the process as a reference, the relevancy of the information provided by the Qualitative Transfer Function-based model is demonstrated. A second model is proposed, which takes into account the mass balance inside the column using approximate knowledge on the relationships between the physical variables involved. The qualitative aspects of the approach allow to capture non-numerical information which is sometimes very useful for supervision purposes.