High Basicity Sinter Research Articles

高碱度烧结矿低温还原过程中粉化机理的研究

于显微镜下观察高碱度烧结矿低温还原20、40、60 min后显微结构的变化。研究发现烧结矿在低温还原时赤铁矿向磁铁矿的转变很少，烧结矿低温还原时显气孔率和体积几乎不变。进一步研究发现，低温还原时铁酸钙分解为赤铁矿生成新的小气孔，随反应的进行气孔变大导致相邻气孔不断合并，使烧结矿变为疏松大气孔结构，强度不断下降，这是造成烧结矿低温粉化的一个重要原因。 The change of microstructure of high-basicity sinter after undergoing low-temperature reduction for 20, 40 and 60 min was observed. The study found that hematite transformed rarely to magne-tite in low-temperature reduction process of sinter, and the sinter’s apparent porosity and volume were almost constant. Further study found that with calcium ferrite decomposing into hematite in low-temperature reduction process, new small pores were generated, and the pores became larger along with the reaction, which resulted in merging of the adjacent pores. After that, the sinter’s structure became loose with big pores, and its intensity decreased, which caused chalking of the sinter in low temperature.

Operation at High Pellet Ratio and Without External Slag Formers – Trials in an Experimental Blast Furnace

Blast furnaces that operate with pellets and sinter normally use high basicity sinter and acid pellets to balance the slag chemistry. When external additives are used, irregular slag formation occu ...

Melting Characteristics and Wettability of Binding Phase in Sinter

The melting characteristics and wettability of the binding phase in high basicity sinter were studied. By changing n CaO: n Fe 2O 3 (molar ratio of CaO to Fe 2O 3) as well as the percentage of MgO, SiO 2, and A1 2O 3, the melting characteristics and wettability of the binding phase were discussed. The results indicated that the characteristic melting temperature was the lowest and wettability was the best at n CaO: n Fe 2O 3 = 1:1 (without addition); the addition of MgO increased the characteristic melting temperature and contact angles; when the percentage of SiO 2 or AI 2O 3 was 3%, the characteristic melting temperature was the lowest, whereas the contact angles increased with an increase in SiO 2 and A1 2O 3 contents.

Stabilizing the composition of blast-furnace products from titanomagnetites with a nonconical loading trough

In Russia currently, titanomagnetite ore is converted to vanadium-bearing hot metal and then vanadium slag (the raw material for vanadium production) at OAO Nizhnetagil’skii Metallurgicheskii Kombinat (NTMK) and Chusov metallurgical plant. The complex blast-furnace batch contains unfluxed pellets and high-basicity sinter from the Kachkanar enrichment facility, manganese sinter, limestone, and coke. The batch composition and its charging sequence largely determine the stability of the product composition. The nonconical charging troughs and a conveyer system for lower charging at the NTMK furnaces impose certain constraints on the production of vanadium hot metal and slag of constant quality. The efficiency of nonconical charging units at blast furnaces largely depends on the control program, as noted in [1]. In the present work, we consider means of stabilizing the product composition in the blast-furnace smelting of titanomagnetites with nonconical charging troughs. The results may be extended to the blast-furnace smelting of batch other than magnetites. The configuration of the materials in the charging bunker, including the order of limestone charging, considerably influences the stability of the product composition, as shown in [2]. Accordingly, the rational method of introducing limestone in the charging bunker is determined in industrial tests. At blast furnace 5, samples of hot metal and slag are taken at 10-min intervals, with different methods of introducing the limestone in the bunker: at the bottom, in the middle, and at the top. Each stage lasts two days. To reduce the influence of random factors on the results, the charging pattern is changed immediately after taking the samples in the previous stage of the test. The samples are taken in steady smelting conditions (i.e., at least 8 h after the change in charging pattern), for two successive discharges each day. From each discharge, eight samples are taken. The overall loading system and the batch distribution over the annular cross sections are not changed significantly during the experiment.

Producing high-basicity sinter from low-silica ore

Experience at OAO MK Azovstal in the production and blast-furnace use of sinter of basicity 1.74 is described. The sinter is produced using unique low-silica ore (∼1% SiO2) in quantities of 195.0–352.6 kg/t of sinter. In appropriate market conditions, this ore may be used to increase hot-metal supplies, to stabilize furnace operation, or to compensate for the losses of hot metal due to furnace shutdown.

Use of high-basicity sinter in the charge of a 3000-m3 blast furnace

Use of high-basicity sinter in the charge of a 3000-m3 blast furnace

Effectiveness of screening high-basicity sinter in a combination sinter processing system

Effectiveness of screening high-basicity sinter in a combination sinter processing system

Blast furnace operated on high-basicity sinter

Blast furnace operated on high-basicity sinter

Application of pyrite cinders in the production of high-basicity sinter

Application of pyrite cinders in the production of high-basicity sinter