A data-driven predictive modeling approach for converter inlet temperature in the copper smelting acid-making process

In the copper smelting Flue Gas Sulfuric Acid, accurate prediction of the converter inlet temperature is of great engineering significance for ensuring safe operation, reducing energy consumption, and improving system stability. To address the strong coupling, long time delay, and pronounced nonlinearity inherent in this process, we proposed a data-driven soft-sensing method designed for real-world industrial applications. The proposed approach was validated in an actual "two-conversion–two-absorption" industrial system. First, the Partial Autocorrelation Function was employed to analyze Distributed Control System data, identifying the most relevant input variables and time windows to provide a high-correlation feature foundation for model construction. Then, a Gated Recurrent Unit neural network was utilized to model temporal dependencies, effectively capturing complex dynamic relationships while suppressing noise interference. Furthermore, an Attention Mechanism was incorporated to enhance the model's focus on key temporal features, improving adaptability to process fluctuations and enhancing the interpretability of prediction results. Finally, the proposed model was implemented and verified in an industrial Flue Gas Sulfuric Acid process. The experimental results demonstrated that the method maintains stable predictive performance and accurately captures the dynamic variation of the first-layer converter inlet temperature. It effectively assists operators in adjusting process parameters in real time, thereby improving system safety, continuity, and operational reliability. The findings verify the engineering feasibility and practical applicability of the proposed method, providing strong technical support for the intelligent operation of copper smelting sulfuric acid production systems.