Agglomerate modifier and using method thereof

Abstract

A agglomerate modifier for blasting iron-smelting and utilizing method are disclosed. The agglomerate consists of calcium chloride 80-90wt%, ferric chloride 10-20wt%, the purity of calcium chloride is up to 93%. The agglomerate modifier is added by water and prepared into modifier solution with 1-4% concentration, and sprayed on the surface of agglomerate by streaming volume of agglomerate 1-3wt%. Its advantages include low cost, to decrease low-temperature reducing pulverizing rate and improve reducing strength index.

Description

technical field [0001] The invention relates to a sinter modifier for blast furnace ironmaking and a method for using the same, belonging to the technical field of ironmaking. Background technique [0002] When using sintered ore to make iron, in the temperature range of 400-600 °C in the upper part of the blast furnace, under the action of the gas reducing agent CO, the sintered ore is formed from hematite (α-Fe 2 o 3 ) reduced to maghemite (γ-Fe 2 o 3 ) during the phase transition process, the volume expands by about 10%, resulting in reduced pulverization and reduced strength. In order to suppress the occurrence of this phenomenon, the method of spraying calcium chloride solution with a concentration of about 3% on the surface of sintered ore is usually used to reduce the low-temperature pulverization rate of sintered ore to a certain extent, but this method cannot completely solve the problem of sintering. Low-temperature pulverization of ore. Chinese patent CN11288...

AI Technical Summary

Problems solved by technology

[0002] When using sintered ore to make iron, in the temperature range of 400-600 °C in the upper part of the blast furnace, under the action of the gas reducing agent CO, the sintered ore is formed from hematite (α-Fe 2 o 3 ) reduced to maghemite (γ-Fe 2 o 3 ) during the phase transition process, the volume expands by about 10%, resulting in reduced pulverization and reduced strength

In order to suppress the occurrence of this phenomenon, the method of spraying calcium chloride solution with a concentration of about 3% on the surface of sintered ore is usually used to reduce the low-temperature pulverization rate of sintered ore to a certain extent, but this method cannot completely solve the problem of sintering. Low temperature pulverization of ore

Chinese patent CN1128890C provides a kind of blast furnace sinter composite surface additive, and this patent uses boric acid and calcium chloride as raw material to make spray agent, sprays on the sinter surface after sintering, although boric acid can suppress the natural pulverization of sinter ( That is, weathering), but it has no obvious effect on reducing the pulverization rate of low-temperature reduction of sinter, nor can it improve the reduction strength index

Chinese patent CN1087784C discloses a method of spraying magnesium chloride solution. Magnesium chloride is used instead of calcium chloride. Although the effect of suppressing sinter pulverization can be achieved, this method causes too much alkali metal to enter the blast furnace, which is not conducive to the maintenance of the blast furnace wall.

Chinese patent application CN1442496A discloses a method of spraying with borax, hydrochloric acid, magnesium chloride and water, which not only has the defect of bringing too much alkali metal into the blast furnace, but also increases the production cost