Modelling liquefied petroleum gas storage and distribution

This paper presents two models for the Liquefied Petroleum Gas (LPG) transfer and storage operations in a refinery. First, a simulation model is proposed, based on Petri Nets, which integrates the continuous and discrete parts of the process. The second model uses mixed integer linear programming techniques for the optimisation and scheduling of the system. The models allow the visualization and simulation of the problem, helping the system operator to easily test and correct scheduling plans despite the complexity of the operations. Results from the simulation model, when applied on the optimisation model, can then be used to reduce the severity of the problem.