Do you have any friends who have done the direct reduced iron process?

Coal-based reduction ("direct reduction") principle (1) Two possible reactions of oxide solid carbon reduction MO(s) + C(s) = M(s) + CO (a) 2MO(s) + C(s) = 2M(s) + CO2 (b) Since the gasification reaction of carbon at high temperatures (≥900°C) CO2 + 2C = 2CO is extremely fast, there is actually very little CO2 in the gas phase, so the latter reaction may occur at lower temperatures. The actual gas phase product of reducing oxides with solid carbon is CO, which is carried out according to the previous reaction. (2) Two possible ways of reducing oxide solid carbon A: Method one: Reaction combination of incomplete combustion of carbon and formation of oxides 2 C(s) +O2 = 2 CO 2M(s) +O2 = 2MO(s) ————————————————————————— 2MO(s)+2C(s)=2M(s)+2CO B: Method 2: Combination of gasification reaction of carbon and indirect reduction reaction of oxide C(s) +CO2 = 2CO MO(s) +CO=M(s)+CO2 ——————————————————————— MO(s)+C(s)=M(s)+CO The thermodynamic equilibrium diagram is shown in Figure 16. (3) Equilibrium diagram of iron oxide reduced by solid carbon (4) Effect of pressure on iron oxide reduced by solid carbon

Are you talking about something called "sponge iron"? I've done it before.

It’s sponge iron. Can you talk about it in detail?

It is an iron-making production process that reduces iron ore into sponge-like iron below the melting temperature of iron. Its product is direct reduced iron (DRI), also known as sponge iron. Sponge iron remains unmelted and retains its ore shape. It is named after the formation of a large number of pores due to reduction and loss of oxygen, and the shape of the mass looks like a sponge when observed under a microscope. Sponge iron is characterized by low carbon content (<1%) and preservation of gangue in the ore. These characteristics make it unsuitable for large-scale use in converter steelmaking, and is only suitable for replacing scrap steel as raw material for electric furnace steelmaking. The content of harmful impurities such as sulfur and phosphorus and non-ferrous metals in sponge iron is low, which is beneficial to the smelting of high-quality steel in electric furnaces. Sponge iron with an iron content of more than 97% is also classified as sponge iron, but when used in the field of powder metallurgy, its shape is divided into block and powder (primary reduced iron powder). If it is further processed, it can also be made into secondary reduced iron powder, and its iron content will reach more than 99%. The main equipment for sponge iron is the sponge iron gas tunnel kiln, whose annual output can reach 50,000 to 80,000 tons of sponge iron. At present, this phase technology is relatively mature.

Generally, pellets are made from iron concentrate - pre-baked at 600℃ - carbon is added for reduction roasting at around 1100℃.

Coal-based direct reduced iron is the so-called "sponge iron". Because iron is reduced in a solid state, it still retains its original ore-like shape, like a sponge, so it is so called! To be honest, it is okay to directly restore the coal base on a small scale. Investing 300 million in a 150,000 to 200,000-ton production line is not the main thing. The key is that the cost of producing iron per ton is too high. The current domestic coal-to-iron ratio is basically 1: 1. Moreover, the grade of iron ore must basically reach above 66%, so it is currently uneconomical to apply it on a large scale in China, even for industrial applications. At present, direct reduced iron is used to produce sponge iron in China, which is mainly used for electric furnace steelmaking. Generally, the addition ratio is less than 35% to reduce costs. If you want to use sponge iron to make steel, it may not be realistic. Currently, MCC Changtian is doing better in this regard in China. You can consult!