The Research Of Multiple Objective Decision Method For The Quality Parameters Of Carbon Anode

In the modern aluminum industry, the production method of aluminum is Hall-Heroult electrolytic process. Electrolytic cell is the main equipment in electrolytic aluminium production. Carbon material is the anode of electrolytic cell, and it plays a double effect of conductive and participating in chemical reactions. So the production of carbon anode (also called pre-baked anode) has a key role in the aluminium electrolysis production process.In the production of carbon anode material, calcination and roasting are very important process steps. They influence the product quality of carbon anode, the energy consumption of production, environmental control and so on. Chinese the 11,12,13 five-year plan strictly required electrolytic aluminum production to achieve energy conservation and emission reduction, scientific production. At the same time, the calcination and roasting of anode is one of the key links which can achieve the requirements.In this paper, the development and research of anode calcination and roasting technology at home and abroad are reviewed. Two phases of technology control modes are analyzed. On the basis of summarizing the theories, this study aims to the qualities of carbon, puts forward the methods of control modeling and multi-objective fuzzy decision to optimize the technological parameters of roasting. The results are compared by simulation experiments and experimental verification. The main works of this paper are divided into the following points:1. The data collected on the spot are disposed. The method of RHM (Resampling by Half-Mean) is used to get rid of abnormal values, which can improve the accuracy of the late data modeling.2. The intelligent optimization methods such as PSO (Particle Swarm Optimization), GA(Genetic Algorithm) and RBF(Radical Basis Function) neural network intelligent modeling method are in combination and applied to the quality parameters control of carbon anode calcination and roasting.3. Carbon anode calcination quality parameters mainly include ash content, volatile component, power specific resistance, sulphur content, true density and so on. Carbon anode roasting quality parameters mainly include ash content, electrical resistivity, the coefficient of thermal expansion, the reactivity of CO2, compression strength, volume density, true density and so on. This study builds up intelligent models. One model is constituted by technological parameters of calcination and the quality parameters of petroleum coke. The other one is constituted by the technological parameters of roasting and the quality parameters of carbon anode. Lastly, the result of modeling are analyzed and compared. This study puts forward the modeling method for quality control in carbon anode calcination and roasting, and this method is based on the quality parameters of carbon anode.4. This study puts forward to optimize the technological parameters of roasting through multi-objective fuzzy decision. The author analyzes the correlation of the technological parameters with the quality parameters in roasting process, uses the technological parameters of roasting as the decision theory domain. According to the quality parameters of carbon anode which are as index function, it optimizes the technological parameters. To realize optimized control effect in the energy saving, consumption reduction and reduce emissions of roasting process.