Development of erosion monitoring model for blast furnace hearth based on moving-boundary method

Abstract

Monitoring the erosive states of a hearth lining plays an important role in the operation and maintenance for an iron-making blast furnace. A simulation model of the calculating erosion profile is established. In computational algorithm, the step-length factor of moving boundary is optimally calculated based on optimised gradient descent method and the temperature of the feedback from thermocouples. Furthermore, the erosion profile and residual thickness of hearth lining are restructured by the moved boundaries. In order to validate the proposed model, taking a hearth of the known profile with the non-uniformed erosion as an example, the developed monitoring model computationally obtains the unknown boundary using the measured temperature of the sample points. Then, through comparing the actual erosion profile and residual thickness of the hearth lining with the calculated values, the model reliability and errors are discussed. The averaged value of the relative errors is about 4·50%.

Keywords:

• Moving-boundary method
• Optimisation theory
• Hearth erosion
• Monitoring model
• Blast furnace