Study Of Slag Flow Real-Time Detection System On Blast Furnace Slag Runner

During the 1980s, the level of the automation of blast furnace has a rapid development at home and abroad. Many countries pay more and more attention to the research of blast detection to find new dynamic model of the development status of the furnace and to establish the integrated control and management system. In the past, the blast furnace slag as a byproduct of the iron production has always been thrown away as waste. But after the study about the secondary comprehensive utilization of resources technology, we find that the blast furnace slag can be used as the cement raw materials or manufacturing ceramic, hollow brick and porous sound-absorbing material and so on. In this way, the waste utilization, reducing of the environmental pollution and improving of the economic efficiency can be easily achieved.So far, in the production of blast furnace in China, the water quenching granulation process is used as the main blast furnace slag treatment process. Which means to wash the slag with high-pressure water to make the slag quench into small particles, then get it on the belt through the filter, remove the water residue and finely ground the slag as cement raw material. During the process that the iron slag and cooling water mixed together, there are many factors would have great influence on the quality of the water residue which include the ratio of the slag flow and the cooling water flow, the temperature of the slag and so on. To monitor the flow of the molten iron slag and improve the quality of the water residue, it is necessary to detect the flow rate of the floating molten slag in the slag ditch. Through the detection, we can also get the proportion of the hot metal and slag, which could monitor whether or not the hot metal will flow into the slag. Besides, information on other parameters can be derived, which has important reference value on the blast furnace slag management.Currently, there are no relevant documents about the detection technique of the slag flow in the slag ditch. To achieve the detection of slag flow, four parameters must be detected respectively which include the slag flow rate, temperature, width and height of the liquid surface. It is hard to achieve accurate measurement since the slag ditch under the erosion and corrosion of the molten slag and the slag's characteristics. A method to detect the real-time flow of the slag is proposed in this article after research and field trips. This method uses image processing technology to detect the surface width and the surface velocity of the molten slag; with ultrasonic transit-time method to detect the liquid level of the slag and use thermocouple to detect the temperature of the high-temperature molten slag intermittently. Then derive the formula of the flow with the parameters detected, based on which we can perform flow calibration to obtain the formula can be used to get the real-time flow of molten slag. The real-time monitoring function of slag flow and each parameter is achieved with Kingview and the slag flow and changes of the parameters can be easily analysised with historical trend curve. Then we can analysis and manage the information of molten slag compratively well. Which would have guiding significance during the iron production process.Finally, experiments show that the real-time slag flow detection system in the slag ditch proposed in this article is feasible, and the system can meet the designed requirements.