Method for firing alkaline pellets by utilizing metallurgical dedusting ash

Abstract

The invention provides a method for firing alkaline pellets by utilizing metallurgical dedusting ash. The method comprises the following steps that 1, various kinds of metallurgical dedusting ash aresoaked with water, mixed uniformly and stored in a sealed mode; 2, the treated dedusting ash undergoes secondary uniform mixing by a barrel-type mixer, pelletizing is carried out after the dedusting ash is uniformly mixed by the barrel-type mixer, and semi-finished products enter a rotary kiln for roasting after fresh pellets are dehydrated, dried and preheated; and 3, after roasting, circular cooling is carried out, and the pellets undergo secondary oxidation and cooling in a circular cooler and then are cooled to obtain finished products. The air permeability of the alkaline pellets preparedby the method is better than that of alkaline sintered ores in the smelting process, the particle size and strength of the alkaline pellets are both higher than those of the alkaline sintered ores, and the alkaline pellets contain less harmful elements, are high in iron removal rate, capable of reducing the coke ratio and stable in grade, and create advantageous factors for reducing iron making cost; and the method has the advantage that a large amount of waste dedusting ash generated in various metallurgy production projects is effectively utilized, so that energy is saved, and the environment is protected.

Description

technical field [0001] The invention relates to a method for firing alkaline pellets, in particular to an energy-saving and environment-friendly method for firing alkaline pellets by using metallurgical dedusting ash. Background technique [0002] The development of circular economy is a major strategic decision of our country, a major measure to promote the strategic deployment of ecological civilization construction, and an inevitable choice to accelerate the transformation of economic development mode, build a resource-saving and environment-friendly society, and achieve sustainable development. [0003] In order to improve air permeability in the process of ironmaking production, the ore powder is generally made into sintered or pelletized before pig iron smelting. During the smelting process, the pellets have uniform particle size, high iron content, good reducibility, and good low-temperature strength. [0004] At this stage, my country's demand for energy resources i...

AI Technical Summary

Problems solved by technology

In the production process of alkaline pellets, the process requirements are relatively high, and the temperature control range is relatively small. After a large proportion of dust removal is added according to the traditional process, kiln sticking and ring formation will occur.

[0006] In addition, other manufacturers use concentrate powder and lime to produce alkaline pellets, which can only reach 1% alkalinity. If you want to increase the alkalinity, it is easy to pop balls during the drying process of the grate machine, which will cause balls Small particle size, poor air permeability in ironmaking process, which is not conducive to production, even when 1% alkalinity is produced, the ball bursting rate is still high