A method for resource utilization of waste activated carbon to achieve emission reduction of nox and dioxin in iron ore sintering

Abstract

The invention discloses a method for realizing iron ore sintering NOx and dioxin emission reduction by recycling waste activated carbon, the method comprises the following steps: water immersion, grinding and drying pretreatment are performed on the waste activated carbon to obtain activated carbon powder, after a urea solution is sprayed on the surface of the activated carbon powder, the activated carbon powder is mixed with raw materials comprising a coarse grain fuel, slaked lime and fine-grain hematite for granulating to obtain a granular material I; raw materials comprising an iron-containing raw material, a fusing agent and a fine granular material are mixed for granulating to obtain a granular material II; the granular material I and the granular material II are uniformly mixed andsequentially subjected to material distribution, ignition and sintering. According to the method, under the condition that the sintering production quality index is not influenced, the waste activatedcarbon is used to replace part of coke powder or anthracite, the waste activated carbon can be recycled, NOx and dioxin emission in the sintering process can be reduced, follow-up tail end treatmentpressure is reduced, and the sintering production cost is reduced.

Description

technical field [0001] The invention relates to a method for reusing waste activated carbon, in particular to a method for resource utilization of waste activated carbon under the sieve of a desulfurization and denitrification activated carbon analysis tower to realize NOx and dioxin emission reduction during iron ore sintering, and belongs to the technical field of iron and steel metallurgy. Background technique [0002] The iron and steel industry is one of the most important sources of industrial pollutant emissions. With the increasing maturity and popularization of desulfurization technology, high-risk pollutants such as NOx and dioxin have received more and more attention. Among them, more than 50% of NOx comes from the sintering process, and sintering is also the second largest source of toxic pollutant emissions after municipal waste incinerators. With the increasingly stringent environmental protection requirements, the state's emission limit for sintering NOx has b...

AI Technical Summary

Problems solved by technology

The cost of a single-stage activated carbon adsorption tower is low, but it is difficult to reach a NOx outlet emission concentration of 100mg / Nm 3 requirements, while multi-stage towers will significantly increase investment and operating costs

[0004] The activated carbon regeneration tower is a device for high-temperature activation of catalysts and recycling of by-products. Activated carbon is heated and eroded by airflow in the regeneration tower, which is prone to wear and tear. After regeneration, it is sieved, and the fine-grained activated carbon under the sieve is discarded, resulting in Large consumption of activated carbon increases operating costs

Waste activated carbon still has a certain adsorption activity, but because it adsorbs K, Na, Cl and other impurities, and the particle size and strength are not up to standard, it cannot be returned to the adsorption tower for reuse, but is mainly returned to sintering to replace part of the fuel. Fine particle size, good reactivity, does not match the combustion performance of traditional coke powder, anthracite and other fuels, directly added to the sintering material will lead to a decrease in the sintering yield and strength of the sintering ore, and the content of harmful impurities in the sintering ore will increase

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