Method and device for reducing metallized pellet by using high-purity water gas in pure oxygen shaft furnace

Abstract

The invention relates to a method of restoring metallized pellet by high purity water gas in a pure oxygen shaft furnace. The process is that: A. mill coal is used for preparing high purity of water gas. The high purity of water is sent into the shaft furnace from the under-part of the blowdowning stone roller of the shaft furnace and used for restoring pellet and high-grade iron ore as reducing gas and cooled gas. B. the moderate amount of pure oxygen is blasted into the upward side of the blowdowning stone roller, so as to burn a part of gas. C. the inlet pressure of gas is controlled by 0.4MPa to 2 Mpa while the pressure of oxygen is above that of gas. D. after dust abatement, gas passes through TRT and a transformation absorption device, and CO2 is recovered. Water vapor is put into a low pressure gasholder after condensation and partial separation. E. gas passing the through blowdowning stone roller is preheated by restored metallized pellet in a thermal state. F. metallized pellet which is cooled by gas is put into under-part of the blowdowning stone roller, and based on varied use, users of the next connection are supplied by different choices of the form of passivation and cooling or heat preservation. The invention has simple process flow, especially greatly expands operating factor and has greater economic and social benefits for less discharging carbon dioxide and improving the environment.

Description

(1) Technical field [0001] The invention relates to a production method of direct reduced iron, mainly a method for reducing metallized pellets in the shaft furnace by utilizing pure oxygen shaft furnace and high-purity water gas. (2) Background technology [0002] At present, the world's direct production of direct reduced iron has reached 60 million tons, of which 90% is the use of CO and H produced by natural gas cracking 2 As a reducing agent, the typical method is the Midex method in the United States. Due to the limitation of natural gas resources and the high cost, the direct reduction of shaft furnaces has not been developed in my country. [0003] Since we have mastered the method of producing high-purity water gas with non-coking coal (see patent: 200610045968.1), it can completely replace the CO and H2 produced by the cracking of natural gas. will develop faster. [0004] No process and equipment for producing direct reduced iron by reducing oxidized pellets, ri...

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Problems solved by technology

[0002] At present, the world's direct production of direct reduced iron has reached 60 million tons, of which 90% is the use of CO and H produced by natural gas cracking 2 As a reducing agent, the typical method is the Midex method in the United States. Due to the limitation of natural gas resources and the high cost, the direct reduction of shaft furnaces has not been developed in my country.

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