Thickening-dewatering process is an important solid-liquid separation process in the field of nonferrous metal beneficiation and metallurgy. However, there are some problems in the process, such as difficult on-line detection of key variables, mutual coupling between production equipment and manual experience operation, which lead to high energy consumption and are difficult to ensure process safety. To solve the above problems, a coordinated optimization model of the thickening-dewatering process based on mixed integer linear programming is constructed in this paper. Based on the historical data of the industrial field, the prediction model of underflow concentration and the prediction model of operation time of underflow pump and pressure filter pump are established. Considering the ladder electricity price, a coordinated optimization model of the thickening-dewatering process is established with the goal of minimizing the energy consumption in the production process and the constraints of production process conditions and equipment safety. By introducing auxiliary decision variables and linearizing the optimization model, the complex nonlinear process problem is transformed into a mixed integer linear programming problem which is easier to be solved. Finally, the proposed method is applied to the thickening-dewatering process of a concentrator. After application, the average concentration underflow during ore drawing is increased by 13.5%, and the economic index of energy consumption is reduced by 46.8%.