Abstract
Scrap-metal is used as a refrigerant during steelmaking process in a basic oxygen furnace where it can reach about twenty percent of the charge. The quantity of the scrap-metal loaded to the basic oxygen furnace determines the cost and quality of the finished steel. But bulk density of the scrap-metal is also an important technological factor that can affect the steelmaking process itself. That is why it is necessary to measure bulk density of the scrap-metal before it is loaded to the furnace. The mass of the scrap-metal in a chute is measured by the specialized scale. If the weight of the scrap-metal is known, the problem can be reduced to finding the volume of the scrap-metal in the chute. However, contact methods cannot solve this problem. This problem was solved by using non-contact method of measuring the distance to the surface of the scrap-metal in the chute by means of a time-of-flight 3D-camera. As a result of the experiment conducted at the oxygen converter shop, there were obtained images of an empty and a full chute. These images are represented by matrixes containing distances for three orthogonal directions. The algorithm used in this paper calculates the scrap-metal volume by subtracting the reference image of the empty chute from the image of the full chute. This work is based on industrial experiments at the oxygen converter shop of Magnitogorsk Iron and Steel Works. The paper describes the problems arising in the application of the described algorithm to the task of scrap-metal volume calculation and offers ways of solving these problems. The proposed algorithm was used to calculate the volume of the scrap-metal. Comparison of the calculated here volume with the volume of the same scrap-metal in the chute that was obtained earlier using a different approach showed that error does not exceed 5%.
Keywords
Metals industry, steelmaking, furnaces, volume measurement, 3D-camera, scrap-metal, bulk density, basic oxygen furnace, non-contact measurement, scrap chute.
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