Optimization of energy and water use in multipurpose batch plants using an improved mathematical formulation

Presented in this contribution is a formulation that addresses optimization of both water and energy, while simultaneously optimizing the batch process schedule. The scheduling framework used in this study is based on the recent and efficient formulation. This formulation has been shown to result in a significant reduction of computational time, an improvement of the objective function and leads to fewer time points. The objective is to improve the profitability of the plant by minimizing wastewater generation and utility usage. From a case study it was found that through applying only water integration the cost is reduced by 11.6%, by applying only energy integration the cost is reduced by 29.1% and by applying both energy and water integration the cost is reduced by 34.6%. This indicates that optimizing water and energy integration in the same scheduling framework will reduce the operating cost and environmental impact significantly.