Method for preparing direct reduced iron by bio-oil

Abstract

The invention relates to a method for preparing a direct reduced iron by a gas base method, in particular to a technology for preparing the direct reduced iron by taking the bio-oil and iron ore powders as raw materials. The method comprises the following steps of firstly sending the bio-oil and water vapor into a water vapor reforming reactor, converting the carbon-hydrogen-oxygen-contained organic matter in the bio-oil into a mixed gas with principle components of hydrogen and carbon dioxide, obtaining a reduced gas with the hydrogen concentration of more than 90vol% by a tail gas purifying and collecting system, subsequently preheating the reduced gas to the temperature of 100-200 DEG C and sending the preheated gas into a reduction reactor containing the iron ore powders, starting a self-heating system and controlling the temperature in the reduction reactor within 650-900 DEG C and keeping the temperature for 1-2h so that the reduced gas and the ferric oxide in the iron ore generate an oxidation-reduction reaction to obtain the direct reduced iron. The method is characterized in that a coke or a natural gas is not needed and the reproducible bio-oil raw material is used and the method has the advantages of being friendly to environment, simple and quick process, low energy consumption, high metallization rate and high production cost.

Description

technical field [0001] The invention relates to a method for preparing direct reduced iron by using a gas-based method, in particular to a technology for preparing direct reduced iron by using bio-oil and iron ore powder as raw materials. Background technique [0002] At present, there are two main smelting methods for iron and steel production: blast furnace ironmaking technology and direct reduction iron technology using natural gas or coal. Among them, blast furnace ironmaking is the main technical method in steel production at present, accounting for about 90% of the steel production output. It uses high-quality iron ore, coke and solvent for slagging as raw materials. The ironmaking process consists of coking, sintering and blast furnace processes, and the energy consumed accounts for more than 30% of the total energy consumption of steel production. And the traditional steel industry is a serious source of pollution. Another method is the direct reduction iron technol...

AI Technical Summary

Problems solved by technology

[0005] Visible, at present existing production direct reduction iron technology mainly has two problems: (1) the raw material and fuel that iron oxide is reduced to metal iron in the prior art are coke or natural gas, and this class raw material is non-renewable fossil raw material, Vulnerable to supply, price and regional constraints, and how to reduce harmful gases (CO, NOx, SO 2 ) and greenhouse gas (CO 2 ) emission problems; (2) In the direct reduction iron technology, hydrogen-rich syngas with a high hydrogen-carbon ratio is required as the reducing gas, but whether it is the syngas obtained from gas vaporization or natural gas reforming, CO occupies a large proportion

[0008] So far, no reports have been found on the application of bio-oil to iron reduction technology

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