Blast furnace ironmaking, the bottom is lower.

During blast furnace ironmaking, the furnace bottom is located at the bottom of the whole blast furnace, which is mainly composed of refractory bricks and refractory concrete, and its function is to prevent slag and molten iron from infiltrating. In the process of blast furnace ironmaking, coke needs to be added from the top, ore needs to be added from the throat and hot air needs to be blown in from the tuyere of blast furnace. The three move in opposite directions and react from top to bottom, and finally molten iron and slag are generated.

The chemical equation of blast furnace ironmaking is as follows:

1. Gasification: CO2+C=2CO (condition: high temperature).

2. Ironmaking: Fe2O3+3CO=2Fe+3CO2 (condition: high temperature).

3. Slagging: CaCO3=CaO+CO2↑ (condition: high temperature) CaO+SiO2=CaSiO3 (condition: high temperature).

The principle of blast furnace ironmaking is the process of putting iron ore, oil, coal, coke and other raw materials into the blast furnace for heating, and taking oxygen away from iron to form iron.

The main equipment for ironmaking is blast furnace. Iron ore, coke and limestone are added from top to bottom during smelting, and hot air is blown into the furnace from bottom to top. At high temperature, the reactants fully contact and react to obtain iron.

Principle:

Blast furnace ironmaking is a complicated process. Its raw materials are iron ore, limestone and coke. The reaction in blast furnace is mainly divided into three parts, the first part is the process of preparing reducing agent, the second part is the main principle of ironmaking, and the third part is the process of removing impurities and slagging. But the iron smelted in blast furnace is impure and contains a small amount of impurities, so it is called pig iron.

2. During ironmaking, iron ore, coke, limestone and other raw materials are added to the blast furnace (ironmaking furnace) in layers according to a certain proportion, and a large amount of oxygen-enriched air heated by the hot blast stove is blown into the blast furnace from the air inlet, so that the coke burns to produce carbon dioxide, which reacts with the hot coke on the upper layer and is reduced to carbon monoxide.

3. Carbon monoxide is added from the top of the blast furnace to react with the falling iron ore. Among them, iron oxide is gradually reduced to liquid iron, commonly known as molten iron. After the reduced molten iron accumulates to a certain extent, it is discharged from the bottom of the furnace.

4. Limestone added during ironmaking plays a role in slagging, with the purpose of making gangue with high melting point in iron ore react with limestone to generate calcium silicate floating on molten iron, so as to separate slag from molten iron.