In this master's thesis, we examined the energy-intensive process of continuous casting of steel. A literature review was conducted on energy efficiency in the steel industry and waste heat recovery from metallurgical processes. Theoretical foundations were presented, followed by the thermodynamic and thermoeconomic analysis of continuous casting of steel. Using the simulation model of continuous casting of steel billets and the JMatPro steel property database, we computed the input data fields and calculated the flows of energy, entropy, and exergy of the considered control volume. We calculated its internal and total exergy efficiency. Based on the thermoeconomic analysis of the electric arc furnace and the ladle furnace, we estimated the exergy cost in the steel plant. We calculated the costs associated with exergy losses during continuous casting of steel and evaluated the economic potential of waste heat recovery within the framework of finite-time thermodynamics. A parametric analysis evaluated the influence of steel grade and casting conditions for 180 mm × 180 mm billets. The analysis included the steels: 16MnCrS5, 46MnVS5, and 100Cr6. For the steel 46MnVS5, the impact of casting temperature in the range of 1515 °C to 1535 °C and casting velocity between 1.58 m $min^{-1}$ and 1.62 m $min^{-1}$ was examined. The results include graphical representations of the calculated fields, highlighting regions of the largest irreversibility. Adjusting casting parameters enables annual economic savings of the steel plant, ranging from €64,900 to €330,700, depending on the steel grade.
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