Argon Oxygen Refining Ferroalloy Furnace Line Detection Method

Energy saving, consumption and emission reduction is the three most active areas of currently industrial production. With the World Climate Conference held in Copenhagen, environmental issues, once again focused the world's attention, energy conservation and environmental protection brook no delay. National Science and Technology Support Planning subjects "Argon-Oxygen refining ferroalloys energy-saving and emission reduction technology application research" is an innovative practice which is presented under the above context. The application of technology AOD Argon-Oxygen refining in stainless steel production is already quite mature, make it applied in the ferroalloy smelting is a new attempt. This article starts from the production reality, taking the real-time requirements, whether the system can be realized and the cost into integrated account, and designs an end-gun infrared colorimetric temperature measurement system.In this paper, firstly clarify the purpose and significance of the temperature on-line measurement in an argon-oxygen refining ferroalloys production. After a detailed analysis of the development status of AOD furnace temperature on-line detection at home and abroad, and by comparing the several commonly used temperature measurement methods, such as the model predicting temperature on-line detection, the sapphire fiber sensing temperature on-line detection, the blackbody cavity temperature on-line detection, and the infrared sensing temperature on-line detection, an improved method of temperature measurement—infrared end-lance temperature measurement is proposed based on the problems of the emissivity amendment difficulties and the low accuracy of the traditional temperature measuring methods. This approach used the gray body features of the isothermal hot metal cavity at the outlet of AOD's bottom gun to avoid a large number of background radiated interference and stabilize the emissivity at the same time. This method effectively solved the problem of inaccuracy of an infrared temperature measurement.As the injecting gas blows into an AOD furnace at the room temperature, aiming at the cooling effect of the blowing gas to the high temperature hot metal cavity, using principles of functional relationship, a temperature compensation model is established in this paper to realize temperature compensation. Synthesizing the temperature inversion model of infrared colorimetric theory and temperature compensation model of blowing gas, the two-step internal calibration of the measurement system is completed. The internal calibration is of good linearity and adaptability to the environment, and its measurement accuracy is better than a conventional laboratory blackbody calibration method. In order to achieve these functions, the four main components, the optical system, the optical fiber transmission system, the signal detection unit and the control and mathematical operation unit are designed and debugged in this paper based on the designing principles of the weak signal detection systems and the analysis of the temperature measurement system's architecture in detail; After the error analysis of the designed systems, some experiments are carried out determine the performance parameters of the temperature measuring system, and the results show that the indicators are to meet the design requirements.The infrared end-gun temperature measurement system is simple, reliable, high precision and low cost, and it has good market prospect.