ESTIMATION OF SILICON TRANSFER BASED ON RADIALLY SAMPLED SLAG AND METAL AT TUYERE LEVEL

A probe capable of measuring radially from tuyere nose to the deadman was installed at a low silicon operation blast furnace. The mechanism of silicon transfer was investigated by using the probe. Molten metal dripps mainly in the region between the end of the raceway and the position of 2.3 m from tuyere nose. [Si] content of the dripping metal in the region controls that of tapped metal. [Si] content at the tuyere level is dependent on (FeO) and (Al2O3) generated from low reduction degree ore and coke ash respectively. [Si] content in the region of 0.9 - 1.3 m from tuyere nose reaches 0.51% which is higher than the tapped value of 0.23%. However, [Si] content in the region of 1.5 - 2.3 m is 0.16%. Totally, average [Si] content at the tuyere level is 0.28%. Consequently, the region which mainly control the overall silicon transfer is above the tuyere level. Amout of desiliconization below the tuyere level is 0.05%, which is the difference between the [Si] content at the tuyere level and the tapped value. The desiliconization reaction occurs mainly below the region of 0.9 - 1.3 m from tuyere nose.