An integrated optimisation model of refinery short-term planning: a case study

A refinery is a complex system that commonly consists of production and utility systems. The production system has various processes, properties and stages that utilise all raw materials to fabricate the final product. Each unit in the production system requires utility commodities provided by the utility system. In providing steam and electricity, the utility system uses the fuel from the production system. In this study, an optimisation model is developed to simultaneously consider production and utility systems in decision making during production planning. This study also considers the use of crude cocktail instead of single crude in the production process. The solution obtained by the integrated model is compared with that obtained by the sequential model. Moreover, the use of single crude is compared with that of crude cocktail. The solutions obtained by the integrated model with crude cocktail yield higher profit than that obtained by the sequential and model with single crude. The model analysis indicates that material cost and production price have a significant effect on the objective function.