Method for measuring molten material level in blast furnace, device for measuring molten material level in blast furnace, and blast furnace operation method

A method for measuring a molten material level in a blast furnace, the method comprising:

• a measurement step of measuring a vibration frequency distribution in a height direction of a furnace body of the blast furnace by using a plurality of vibration meters arranged at predetermined intervals along the height direction of the furnace body;
• a vibration intensity calculation step of calculating a vibration intensity in a frequency range due to blast at each of measurement positions by performing Fourier transform on the vibration frequency distribution;
• a numerical analysis step of calculating a maximum vibration intensity distribution of a lower part of the blast furnace by using a numerical analysis model in which the molten material level and a blast amount in the blast furnace are set as variables;
• and
• a molten material level calculation step of calculating the molten material level at which a difference between the vibration intensity calculated in the vibration intensity calculation step and the maximum vibration intensity distribution calculated in the numerical analysis step is minimized, and determining the calculated molten material level as a position of the molten material level in the blast furnace.