Gas-based shaft furnace, gas-based reduction-oxidation pellet system and method of using the system

Abstract

The invention particularly relates to a gas-based vertical furnace, a gas-based reduction oxidation pellet system and a method applying the same. The inner cavity of the vertical furnace body comprises a reducing section and a cooling section, wherein the reducing section comprises an oxidation pellet inlet, a spiral slideway, a first surrounding pipe, a second surrounding pipe, and a furnace topgas outlet; the oxidation pellet inlet is arranged at the upper end of the inner cavity; the spiral slideway which is bent downwards is arranged at the position from the inner cavity below the oxidation pellet inlet to the middle of the inner cavity, the upper part of the spiral slideway is a curved surface part, and the lower part of the spiral slideway is a grid part; the first surrounding pipesurrounds the outer side of the middle of the furnace body, a first nozzle of the first surrounding pipe extends into the inner cavity; the second surrounding pipe surrounds the outer side of the middle lower portion of the furnace body, the second surrounding pipe is arranged below the first surrounding pipe and is provided with a second nozzle extending into the inner cavity; and the furnace topgas outlet, located on the top end side of the curved surface part, is formed in the inner cavity; and the cooling section comprises a reduced iron outlet arranged at the bottom of the inner cavity.The vertical furnace has the advantages that preheating effect of the pellet can be improved, energy can be reasonably utilized, and production efficiency can be improved.

Description

technical field [0001] The invention belongs to the technical field of iron and steel metallurgy, and in particular relates to a gas-based shaft furnace, a gas-based reduction and oxidation pellet system and a method for applying the system. Background technique [0002] There are two types of direct reduction methods: gas-based and coal-based. The gas-based direct reduction method has become the mainstream technology of non-coking coal metallurgical processes because of its advantages of high volume utilization, high thermal efficiency, and high productivity. The raw materials used in the preparation of sponge iron by gas-based shaft furnace are oxidized pellets, oxidized pellets or composite binder pellets. The oxidized pellets are made of high-grade iron fine powder, and the iron content is greater than 66%. According to my country's natural gas, High-grade iron ore is scarce, and the direct reduction process in my country should use iron concentrate as raw material, and a...

AI Technical Summary

Problems solved by technology

In the production of the existing shaft furnace, due to insufficient waste gas for drying the green pellets, the green pellets are put into the furnace before they are completely dry; When exposed to high-temperature gas, it often bursts and produces a large number of broken balls and powders, causing bonding and affecting equipment operation rate

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