Bell type blast furnace smelting method by using small-size sinters

Abstract

The invention discloses a bell type blast furnace smelting method by using small-size sinters. The method comprises the steps as follows: loading, that is, ore and coke both containing the small-size sinters are added into a bell type blast furnace; blowing, specifically, air blast kinetic energy is controlled to be 150-230kJ / s, the air blast temperature is not lower than 1,180 DEG C, and the air blast oxygen enrichment percentage is not lower than 1 percent; wherein, the small-size sinter comprises the following components by weight percentage: 45-55 percent of sinter which is 3-5 mm in particle size, 35-45 percent of sinter with particle size greater than 5 mm and 0-20 percent of sinter with particle size smaller than 3 mm. According to the bell type blast furnace smelting method by using small-sized sinter, disclosed by the invention, the defect that the small-size sinter cannot be used by a bell type blast furnace for smelting is overcome, and by regulating process parameters, the normal production is ensured and the economic benefit is improved. Moreover, the processing cost of sorting the grades of the singers is reduced by recovering the small-sized sinters in returned ore into the blast furnace for smelting. Furthermore, by adopting the small-size sinters, the state of the material shortage of blast furnace is eliminated, and the cost of raw materials is lowered.

Description

technical field [0001] The invention belongs to the technical field of ore smelting, and in particular relates to a method for smelting in a bell blast furnace using small-sized sintered ore. Background technique [0002] Small-sized sinter refers to sinter with a particle size greater than 3mm in the blast furnace sinter undersieve, and it occupies a large proportion of blast furnace return ore. Usually, the sintered ore with particle size > 5mm can be smelted directly as a finished product. However, due to problems such as finished sieve, under-ditch sieve specifications, and sieving efficiency, it is impossible for the returned ore to be completely sintered ore with a particle size of <5mm. Small-sized sintered ore with a particle size of 3-5mm. [0003] The recycling of small-sized sinter can not only alleviate the "bottleneck" of sinter supply, but also avoid energy waste, which in turn saves a lot of operating costs for enterprises. Through the tracking and an...

AI Technical Summary

Problems solved by technology

Therefore, when the bell-less blast furnace uses small-sized sinter, the operation of charging, distributing and blowing air is complicated.

[0005] In addition, there are many domestic and foreign documents and patents on the use of small-sized sinters for grading into bellless blast furnaces, but none of them are bell-type blast furnaces.

Images