Consteel electric arc furnace, as one typical short-process smelting equipment, is widely applied in many steel plants. Nevertheless, similar to basic oxygen furnace (BOF), the steelmaking process in Consteel electric arc furnace is also a complicated multivariable high-temperature physicochemical process, and the fluctuation of process parameters in Consteel electric arc furnace would make it difficult to stably control the end-point target. The impurities such as phosphorus should be kept under control in the steelmaking process due to their possible adverse effects on the steel quality. [1] Thus, the endpoint phosphorus (P) content is one of the main target values at the end of smelting operation in the steelmaking process due to its significant influence on the steel products, [2][3][4][5] particularly for low phosphorous steels production. To enhance the dephosphorization efficiency, a lot of industrial experiment is carried out to determine the optimal parameters. For instances, Liu et al. [6] investigated the dephosphorization ratio of hot metal with 80 t BOF, and the experiment results showed that the suitable process conditions for obtaining a high dephosphorization ratio in the converter were that the basicity of slag was 1.2-2.0, and the temperature for the intermediate deslagging was 1600-1700 K. Wu et al., [7] through the industrial test of 120 t converter, determine the process of double slag operation in BOF to stabilize the dephosphorization effect. Yang et al. [8] applied the high-temperature laboratorial experiments to investigate the influence of temperature on the dephosphorization of hot metal at the low temperature range of 1300-1450 C with the slag of the low basicity (CaO/ SiO 2 ) of about 1.8. Tian et al. [9] reported that the effects of Fe 3þ content and the basicity of the dephosphorization slag on dephosphorization were greater than those of the decarbonization slag. Yang et al. [10] make a test in 180 t BOF and determine the range of smelting parameters to reduce the end phosphorus less than 0.007%. The reference mentioned earlier is to optimize the dephosphorization process parameter according to the industrial experimental data; however, optimizing the dephosphorization process parameter according to the actual production data is rare. With the improvement of data storage technology and information collection technology, a large number of actual production data can be obtained. [11,12] From these actual production data, we can obtain a lot of valuable information, which is benefit for adjusting the process parameters to improve the dephosphorization ratio. However, in the face of a large amount of data, it is impossible to mine the valuable information just by human. Data mining techniques are mainly used to mine the hidden information, and their patterns justify their importance in decision making. [13] For examples, Pal and Halder [14] utilized the multiobjective optimization technique to address important issue of achieving low phosphorus content along with high-end blow temperat...