Research And Application On The On-line Temperature Detection Of Aluminum Cell Shell And The Cell Status Diagnosis Expert System

Aluminum cell is the main aluminum producing equipment with so much energy consumption as 13000kWh per ton, so it makes sense to study the method to reduce energy consumption. In this paper, the aluminum cell temperature on-line inspecting system was constructed, shell temperature was collected, relationship between shell temperature and freeze profile was studied, aluminum cell status diagnosing expert system was designed, realizing the inspection of aluminum cell energy and material balance, achieving the object of reducing energy consumption.(1) The on-line detecting system for shell temperature was constructed.Shell temperature detecting system consists of industrial computer, temperature transform module, temperature transform apparatus and thermocouple. Temperature signal is transferred to the transform module through thermocouple. After the temperature is transformed into digital signals, the signals are transferred to the temperature transform apparatus and again to the industrial computer through temperature transform apparatus, followed by signal processed, database managed and alarm notice. On one hand, the measured temperature values are stored and displayed as the form of table, and on the other hand, its values are provided as basis for the aluminum cell status diagnosing expert system.(2) The temperature and freeze profile simulation system was designed.Based on shell temperature and related technical parameter, finite volume method was used to construct freeze profile quasi three dimension simulation model based on soft measure principle. Fortran and Visual Basic software was used to develop aluminum cell temperature field simulation program displaying the current freeze profile。(3) The aluminum cell status diagnosing expert system was developed.According to inspected temperature of shell, the result of freeze profile simulation and aluminum cell technical parameter, the expert system database was built in the mode of object-property-value and stored in tree structure. Based on the cause of its failure, phenomenon and disposal of the diseased aluminum cell, rules for expert system was produced by the fuzzy producing method, and the energy balance diagnosing for aluminum cell was realized.Some original points in this paper: Based on shell temperature inspected values and freeze profile simulation results, the on-line shell temperature detection, numeric simulation and AI technology were integrated to fulfill the diagnosis for aluminum cell status.More than half year's application verified its stability and high intelligence. The error between freeze profile simulation result and the measured value was less than 2cm. The diagnosis expert system can effectively prevent malfunction of aluminum cell, ensure its stable production. The technical indexes of aluminum cell were improved with application of our research, with electric efficiency enhanced from 92.8% to 93.5%, and energy consumption decreased from 13715 kWh/t-Al to 13578 kWh/t-Al.