Modeling and Conflict Detection of Crude Oil Operations for Refinery Process Based on Controlled Colored Timed Petri Net

Recently, there has been a great interest in the modeling and analysis of process industry, and various models are proposed for different uses. It is meaningful to have a model to serve as an analytical aid tool in short-term scheduling for oil refinery process. However, in oil refinery process, there are special constraints and requirements, and the existing models cannot be applied directly. Thus, as an application in this paper, we extend the hybrid Petri net to model the crude-oil operations in oil refinery process. This Petri net is called controlled colored timed Petri net (CCTPN). In this model, a token carries both discrete and continuous properties. A token in a discrete place shows its discrete properties, while the continuous properties are captured when it is in a continuous place. A discrete transition treats a token just as a discrete one, and a continuous transition deals with it as a continuous one. In this way, we integrate the discrete and continuous processes together in the CCTPN. Based on the CCTPN, liveness for CCTPN is defined, and with the liveness definition we show how to detect conflicts in scheduling the system by using this model.