The industrial park is a typical complex energy system. Multi-energy complementation can be achieved by making use of the coupling mechanism of multiple energy sources

which can significantly enhance the economic efficiency and energy utilization of plant. Thus

this paper proposes a multi-energy cooperative optimization model of integrated energy system in the plant considering stepped utilization of energy. Firstly

the structure of the integrated energy system in a plant is described. Then

the energy production equipment

energy conversion devices

and energy storage devices in the integrated energy system are independently modeled. Taking the lowest daily operation cost as the optimization objective

the mixed integer linear programming method is used to solve the model under the constraints of cooling and thermal power balance and the physical constraints of equipment. The proposed model follows the idea of scientific energy use of “grade counterparts

stepped utilization”

which achieves the stepped utilization of energy according to the grade of heat. Thus the optimization of industrial production process and equipment operating parameters is realized. Finally

the example analysis shows that the proposed optimal dispatch strategy is more suitable for the actual demand of engineering

and can reduce the operation costs of industrial users.