Research And Development Of The Air Drying Process Water Soft Measurement System

Pneumatic drying is one of key procedures in the process of flash smelter. Keeping the moisture content of concentrate between 0.1% and 0.3% is an important premise of flash smelting process. Because the moisture content of concentrate in dust collecting room is difficult to detect on-line, the controlling method according to experiences causes great fluctuation in the moisture content of concentrate. So it is necessary to develop soft-sensing system to forecast the moisture content on-line in pneumatic drying process.Based on mechanism analysis of pneumatic drying, the principal factors that influence the moisture content are acquired. The heat balance model of moisture is proposed through analyzing the heat transfer mechanism, and the PCA regress model of moisture is presented on the basis of mass collecting data by using statistical analysis. According to the advantages of two models, the soft sensor model is established. An intelligent coordinator is designed to coordinate the heat balance model and the PCA regress model by using the expert rules. The simulation results show that the soft sensor model is valid and feasible, the prediction precision is improved. On-line correction method of soft sensor is proposed to guarantee that the prediction precision would not decrease along with the changes of working condition, and the robustness of the model is enhanced.A soft-sensing system for the moisture in pneumatic drying process is developed. The software is programmed with VC++ and adopts modularization design. The application software communicated with the configuration software with OPC technology. By collecting the real-time data, soft sensor of the moisture is implemented with functions of visual monitoring, data management, printing, and so on. Results of industrial operation indicate that the system predicts the moisture content of concentrate accurately and settles the foundation for optimization control of pneumatic drying.