Al_2O_3含量对烧结矿平衡相组成及特性的影响

Influence of Al_2O_3 on Sinter for Its Phase Compositions and Properties in Equilibrium

为寻求烧结矿在Al2O3含量提高后冶金性能变化的内在原因,实验研究不同Al2O3含量烧结矿的平衡相组成、组元分布特性以及Al2O3对烧结矿物相结构、组成的影响行为,分析Al2O3含量对烧结矿冶金性能的影响。得出:烧结矿中Al2O3含量提高时,其全部进入铝固溶复合铁酸钙相并导致该矿物明显增加。该物相的化学组成可由w(Al2O3)=1.5%时的7.7CaO·13.6Fe2O3·Al2O3·3.4SiO2转变为w(Al2O3)=3.0%时的4.8CaO·11.4Fe2O3·Al2O3·2SiO2;磁铁矿相和粘结相硅酸二钙会随Al2O3含量提高而减少。这种改变使烧结矿的还原性能得到一定改善,但也是引起高铝烧结矿性能劣化的主因,对高炉顺行不利。

To obtain the internal mechanics of metallurgical properties variety of sinter as Al2O3 content level raising ,it was studied that Al2O3 behavior acts on phase compositions and element distributions in equilibrium in sinter and the influence on the phase structure and metallurgical properties of sinter was investigated as well.The results showed that all of Al2O3 existed in the complex calcium ferrite solid solution with aluminum-bearing, and this phase increased greatly as the increasing of the content of Al2O3. As a reasuh,its chemical formula changes from 7.7CaO·13.6Fe2O3·Al2O3·3.4SiO2 to 4.8CaO·11.4Fe2O3·Al2O3·2SiO2 when the percentage of Al2O3 was from 1.5 up to 3.0. Magnetite and calcium silicate were decreased with the content of Al2O3 increasing. These changs were the main reason which the metallurgical properties of sinter with high level Al content was deteriorated, in spite of reducibility of sinter improving, which was harmful to BF operation.