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Pellet is one of the important feeds to iron blast furnace and increased proportion of the pellet is used around the world. Pellet production is cleaner than sinter and its uniform properties allow stable blast furnace operations. Boron iron concentrate is a by-product during production of boron and contains approximately 54% Fe, 3–6% B2O3, and 10% MgO. B2O3 can form liquid binding phase inside the pellet at relatively lower temperature which reduces the fuel and refractory consumption during the pellet production. MgO can reduce the reduction expansion rate of the pellets. Effects of boron iron concentrate, preheating temperature, and time on the strength of the preheated pellet have been investigated. It was found that the compressive strength of the preheated pellet with addition of boron iron concentrate was increased with increasing preheating temperature and time. When the pellets were preheated at 1030 °C for 25 min, the strength of the pellets with 50% boron iron concentrate can reach more than 600 N/P. The optimized parameters can significantly increase the strength of the pellet and reduce the loop formation of the rotary kiln.

The growth rate of ring formation increased when titanium-containing powder had been added into Shougang grate-kiln to produce titanium-containing pellets, which had a strong impact on the production processes. In this article, the mechanism and influencing factors of the ring formation problem had been studied, based on sampling and analyzing samples from different parts of kiln. The result indicated that liquid phase of low-melting point and particles were the main reason of ring formation. The ring formation was difficult to clean up because its strength increased in the high-temperature oxidability atmosphere. The desiccation and preheat of green-ball were degraded when the titanium-containing fines had been added. A large amount of powder and particles were produced in kiln because of the lower compressive strength of dry-ball, which led to the rapid growth of rings.

Low-silica pellet is beneficial for blast furnace to reduce the amount of slag and fuel rate. However, the reduction swelling of low-silica pellet is serious. The effects of TiO2 and MgO on...

The use of pellet with low SiO2 content in blast furnace (BF) will reduce the slag amount as well as fuel rate and increase the productivity. In this paper, the effect of the firing temperature and...