Method for making pellet by fine-grinded steel slag instead of bentonite

Abstract

The method to use fine-grinding steel sludge instead of bentonite to prepare the pellet ore comprises: a. fine grinding the steel sludge into power with 200items content more than 90%; b. adding 1-10m% former steel sludge into refined iron powder instead of bentonite; c. adding 6-10% water into the mixture; generating 8-20mm raw roll; d. sending former balls into shaft furnace or chain-pellet for drying and baking. The experiments show the product has up to the standard, increases grade 2.2% and reduces SiO2 1.7%, and realizes sludge recovery.

Description

Technical field: [0001] The invention relates to waste utilization of converter steel slag, in particular to a method for producing pellets by using finely ground steel slag instead of bentonite. Background technique: [0002] At present, my country discharges more than 40 million tons of steel slag every year, accounting for 12.09% of solid waste in the iron and steel industry, and its comprehensive utilization rate is only 36%. It is mainly used as blast furnace flux and sinter raw materials, steel slag cement, bricks and blocks. Converter slag generally contains Fe 2 o 3 15~25%, CaO45~50%, SiO 2 8 to 15% and a certain amount of MgO, S, P, etc., and the metal iron content in steel slag is calculated as 14%, so a large amount of metal in the piled steel slag has not been recovered, and the converter steel slag is discarded in the slag yard, which is not only a waste It consumes resources, takes up a lot of land, and causes environmental pollution. Therefore, the compreh...

AI Technical Summary

Problems solved by technology

Converter slag generally contains Fe 2 o 3 15~25%, CaO45~50%, SiO 2 8 to 15% and a certain amount of MgO, S, P, etc., and the metal iron content in steel slag is calculated as 14%, so a large amount of metal in the piled steel slag has not been recovered, and the converter steel slag is discarded in the slag yard, which is not only a waste resources, but also occupy a large amount of land, and cause environmental pollution

Therefore, the comprehensive utilization of converter steel slag has been included as an important link in the development of circular economy in the iron and steel industry, but there is no literature report on the new technology of using steel slag, reducing consumption, and exploring the use of finely ground steel slag instead of bentonite to produce pellets

Bentonite is usually used as an additive in the production of pellets, and bentonite contains SiO 2 At about 60%, the iron content of the pellets will decrease, and the energy consumption of the blast furnace will increase