Effect of Coke Reactivity on Sinter Softening-melting Property by Simultaneous Evaluation Method of Carbonaceous and Ferrous Burdens in Blast Furnace

Abstract

In future blast furnace operation which aims at low carbon consumption, it is indispensable to optimize the quality of carbonaceous and ferrous burdens, not evaluations of each individual but both sides of them considering interactions under the coexistence. Therefore, a simultaneous evaluation method of carbonaceous and ferrous burdens at cohensive zone of blast furnaces by softening-melting test which simulated the temperature profile in blast furnaces determined by reactivity of coke was developed. The effect of sinter ore reducibility and coke reactivity on sinter soften-melting property at cohensive zone of blast furnaces were evaluated. With increasing CRI, coke reactivity, gasification start temperature lowers as a result of increasing the reduction rate of sinter at 900-1 000°C and increasing softening shrinkage resistance at the initial stage of the shrinkage near 1 200°C.

Decrease in Carbon Consumption of a Commercial Blast Furnace by Using Carbon Composite Iron Ore

“…1) As a solution, including for coke reactivity enhancement, [2][3][4][5] a method was found for faster reduction and gasification reaction (coupling mechanism) by closely arranging iron ore and carbonaceous materials, and this mechanism was extensively studied. [6][7][8][9] Many of the results of these studies suggest that the use of carbon composite iron ore in blast furnaces will improve the efficiency of reduction reaction, and thus proves also, as it is reported, the result of its use in a commercially operated blast furnace.…”

The Effect of Abandoned Basic Oxygen Furnace Gas Blowing on the Softening–Melting–Dripping Performance of Full High Cr‐Bearing Vanadia–Titania Magnetite Pellets

“…T 40 is the temperature at which the burden shrinkage rate is 40%. T s is the temperature at which the pressure drop steeply increases to 500 Pa. T d is the temperature at which the weight of dripped substance reaches 20 g . For the softening zone, the results show that with the concentration of CO 2 in ABOFG increasing from 0% to 30%, T 4 decreased from 1187 to 1173 °C, T 40 decreased from 1271 to 1254 °C, and [ T 40 – T 4 ] reduced from 84 to 81 °C.…”

“…T 40 is the temperature at which the burden shrinkage rate is 40%. T s is the temperature at which the pressure drop steeply increases to 500 Pa. T d is the temperature at which the weight of dripped substance reaches 20 g. [10][11][12][13][14][15] For the softening zone, the results show that with the concentration of CO 2 in ABOFG increasing from 0% to 30%, T 4 decreased from 1187 to 1173 C, T 40 decreased from 1271 to 1254 C, and [T 40 -T 4 ] reduced from 84 to 81 C. These variations indicate that the softening process of HCVTM ore occurred even earlier, and the position and height of the softening zone declined, which were beneficial to the improvement of the gas permeability in the block-softening zone. [6,12,16] In addition, for the melting-dripping zone, as the concentration of CO 2 in ABOFG increased from 0% to 30%, T s was almost maintained at about 1322 AE 2 C, and T d decreased from 1517 to 1500 C. Obviously, the results indicate that [T d -T s ] reached its lowest test point of 177 C when the concentration of CO 2 was 30%, whereas T s and T d were 1323 and 1500 C, respectively.…”

New Evaluation Methods Discussion of Softening–Melting and Dropping Characteristic of BF Iron Bearing Burden

“…The softening temperature interval (Δ T 1 ) was defined as difference value between softening start temperature and softening end temperature, which was used to evaluate softening properties of iron bearing burden, the softening temperature interval parameters have not been reported in the foreign literature . As can been seen from Figure , the softening temperature interval was 4–40 or 10–40% of charge column height shrinkage, among which most researchers tend to use the latter.…”