Facility and method for producing direct reduction iron by iron ore powder coal derivation

Abstract

The invention provides a facility and a method for producing direct reduction iron by iron ore powder coal derivation, and belongs to a coal derivation method for producing direct reduction iron. The method comprises the following steps: (1) feeding iron ore powder into a multi-stage preheater, and flowing in the multi-stage preheater with high-temperature flue gas in a countercurrent manner to complete quick drying preheat of the iron ore powder and cooling of the high-temperature flue gas; (2) feeding the high-temperature iron ore powder and reduced coke in a reduction rotary kiln to form an ore-coke mixture, providing high-temperature airflow to combustion of the rotary kiln by a burner, and reducing the ore-coke mixture by means of heating to form an iron powder mixture; (3) simultaneously feeding the iron powder mixture and the reduced coal into a cooling rotary kiln by virtue of a connector to complete iron powder cooling and reduced coal coking to form iron-coke mixture; and (4) performing screening and magnetic separation on the iron-coke mixture to separate the reduced coke, direct reduction iron and slag charge, and supplying the reduced coke serving as a reducing agent to the reduction rotary kiln. The method can be used for combining iron powder cooling and reducing agent preparation, and has the advantages of large energy-output scale, low cost and high heat utilization.

Description

technical field [0001] The invention relates to a facility and method for producing direct reduced iron, in particular to a facility and method for producing direct reduced iron based on iron ore pulverized coal. Background technique [0002] As an important raw material for iron and steel smelting in my country, direct reduced iron is increasingly favored by iron and steel enterprises. The production of direct reduced iron can be divided into gas-based method and coal-based method. Due to the lack of natural gas resources in my country, the complexity and high cost of coal-to-gas process, and the technology of gas-based method is monopolized by foreign countries, it is difficult to adapt to my country's national conditions. The mainstream coal-based process in my country is the rotary kiln reduction pelletizing process. The raw materials go through drying and grinding, humidification and pelletizing, pellet sintering, pellet cooling, rotary kiln heating and reduction. The r...

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Problems solved by technology

[0003] The purpose of the present invention is to overcome the shortcomings of high energy consumption, low output, unsatisfactory working conditions and high cost in the production of direct reduced iron by the rotary kiln coal-based method, and provide a method for producing direct reduced iron based on iron ore pulverized coal

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