Online Detection Of Slag/Iron Ratio In Blast Furnace Taphole Based On Multiple Features Of Slag-Iron Flow Stream Trajectory

Real-time online and accurate measurement of the Slag/Iron ratio of blast furnace taphole slag-iron flow is of great significance for guiding blast furnace low Slag/Iron ratio intensified smelting.However,the slag-iron flow of the taphole has the characteristics of high temperature,high speed,high gloss,etc.,and there is strong dust interference near the tappet,which makes it difficult to directly obtain the Slag/Iron ratio online.Therefore,this paper builds a numerical trajectory knowledge base of slagiron flow based on computational fluid dynamics(CFD)and proposes a real-time online detection method for Slag/Iron ratio of blast furnace taphole slag-iron flow based on the multi-characteristics of the stream trajectory,which breaks through taphole slag.The Slag/Iron ratio of the iron stream is difficult to detect online.The main work of this paper is as follows:(1)The numerical trajectory knowledge base of slag and iron outflow from the blast furnace taphole based on the wall jet model is constructed.The wall jet model of the blast furnace tapping process was established,and the variation law of the slag-iron outflow trajectory with the slag-iron ratio,taphole size,and elevation angle was revealed.Numerical simulation was carried out by ANSYS,and the slag-iron outflow trajectory under different conditions parameters was obtained.Outflow trajectory and formed a knowledge base.(2)A method based on the two-stage optimized Hough transform is proposed to fit the real-time image stream boundary of the taphole slag and iron flow.Firstly,an image edge extraction method based on the adaptive prior direction factor is proposed,which effectively reduces the number of stream burr edges and environmental noise points.Secondly,based on the slag and iron outflow trajectory,the spatial range and step size of the Hough transform parameters are optimized,and the real-time and accurate fitting of the stream boundary of the slag-iron flow image is realized.(3)A calculation method of slag-iron ratio based on multi-feature similarity matching of stream trajectories is proposed.Firstly,aiming at the difference between the boundary expansion coefficient of the slag-iron flow numerical trajectory and the actual slag-iron flow boundary,the boundary expansion coefficient of the slag-iron flow real-time image stream is calculated based on the jet theory.Secondly,multiple features such as trajectory features,boundary features,and moment features of the slag-iron flow numerical trajectory boundary and the real-time image stream boundary are extracted,respectively.Finally,a multi-feature similarity calculation model based on the normalized weighted Euclid distance is proposed,and the iron Slag/Iron ratio is calculated based on the multi-feature similarity matching.The experimental results show that the relative error of the proposed method is within 5.0%,which meets the production requirements of blast furnaces.