Research On On-line Infrared Monitoring System Of Melt Temperature In AOD Furnace

At present,in the metallurgical industry,the temperature measurement in the AOD furnace during the smelting process is measured by the operator inserting a thermocouple into the surface of the molten steel.Because the temperature during smelting is too high,the top of the thermocouple will be damaged when it touches the surface of the molten steel during the temperature measurement process,which will cause the same temperature measurement point to use multiple thermocouples to measure the temperature,thus increasing the temperature measurement.Instability and increased loss of thermocouples,at the same time,due to objective factors such as the use of thermocouples to measure temperature requires manual operation and few temperature measurement points,resulting in poor safety,increased consumption of smelting raw materials,and large fluctuations in production capacity,resulting in the quality of steel smelted Rework and other problems due to failure to meet standards.Therefore,it is urgent to achieve energy conservation and emission reduction,reduce smelting costs,improve smelting efficiency,and improve the market competitiveness of metallurgical enterprises through technological progress.According to the research and analysis of the above-mentioned AOD furnace temperature measurement problem,a relatively complete non-contact infrared temperature measurement system is designed.This system adopts the furnace mouth temperature measuring device to cooperate with the bottom temperature measuring device.The furnace mouth temperature measuring device is installed outside the furnace body when the furnace body is tilted,and the light hole is aligned with the furnace mouth.Bottom gun,after simple transformation,the light path and the gas path can be shared one way.The infrared radiation in the furnace detected by the thermometer is analyzed by means of infrared dual-light colorimetric temperature measurement,and the original optical path system is re-optimized and designed,and the optical path is directly divided into two independent optical paths by a beam splitter.It solves the problems of low timeliness and poor durability of the original optical path.The jet characteristics,gas-liquid heat exchange characteristics and physical structure of gas-liquid interface of smelting gas blown into the furnace and molten steel in the furnace at the nozzle during the smelting process of AOD furnace are studied and analyzed.isothermal blackbody model.Then through the research and analysis of the chemical reaction between the molten steel in the smelting furnace and the blown gas at different stages,it is divided into three stages: large-scale blowing,small-scale blowing and reduction to conduct temperature compensation research.The corresponding temperature compensation model,through the control of the host computer,analyzes and calculates the collected data,and enters the corresponding temperature compensation according to different conditions.The finite element method is used to briefly analyze the temperature field in the AOD furnace.According to the characteristics of the heat source of the AOD furnace,the influence of the heat source point on the temperature field in the furnace is analyzed in units of point to line and then to surface.At the same time,a comprehensive overview of the temperature measurement system is given.At the same time,the upper computer system is designed based on the software Lab VIEW,and two application methods with PLC control system and without PLC control system are added to the designed system,and based on the two temperature measurement control systems,the existing AOD furnace The smelting process is improved.The designed temperature measurement system is calibrated in the laboratory and on site,and then the calibrated temperature measurement system is applied in actual production for inspection.Through the analysis of the measured data,it can be known that the temperature rise rate and thermoelectricity calculated by the temperature measurement system are calculated.The temperature rise rate calculated by the couple is basically the same,the average error is less than 0.3?/min,the error between the average temperature measured by the temperature measurement system and the thermocouple measurement value is less than 3.0?,and the relative standard deviation is less than 0.12%.It improves the production efficiency,promotes the effect of energy saving and emission reduction,and increases the production efficiency of the enterprise.