Experimental Research for Operating Thermal Electric Plant Ash in Coating Powder Production Used in the Continuous Steel Casting Lines

In this paper the authors present obtaining of a technological powder used for the continuous casting of steel. The powder is applied in the casting plant distributor to ensure thermal insulation, prevent oxidation of the steel and especially to capture the steel inclusions. The powder helps to purify the steel and thus improve its quality. The paper presents the physical and chemical characteristics of the power plant ash, which is a fine-grained waste, stored in dumps and which can be used for the production of coating powders. Several experimental recipes were made, in which the proportion of power plant ash was between 65-80%. To characterize the recipes, measurements were made to determine the humidity, volumetric mass, spread area, particle size analysis, melting temperature and chemical analysis. After analyzing the physical, chemical and thermal characteristics, pilot experimental batches were performed for testing in the steelworks. The favourable effects of the use of Cenoterm powder were highlighted by analyzing the slag samples taken from the experimental batches. These showed an increase in the MnO content of steel up to 30%, an increase in alumina, magnesium and a decrease in silica. They show that the molten powders in the formed slag are reactive and play a beneficial role in the quality of the steel. Consumption of ash-based coating powder was between 0.065 and 0.22 kg/t liquid steel