Process flow of steelmaking plant

Complete process flow of iron and steel plant:

Mining → mineral processing → sintering → ironmaking → steelmaking → hot rolling → cold rolling → silicon steel.

Auxiliary production processes: coking, oxygen production, gas, self-provided electricity and power.

Iron powder is produced after mining in concentrator, and its iron content is generally above 60% (the higher the better). The method of obtaining iron from iron powder is to use blast furnace reduction method.

In order to adapt to blast furnace smelting, iron powder must be processed into blocks first, which requires that iron powder and limestone be made into blocks with uniform size by sintering machine or pelletizing equipment.

When adding to the blast furnace, coke (as fuel, it also plays an auxiliary role) is added, and hot air (about 1 150 degrees) is blown into the blast furnace. In this way, liquid molten iron will form at the bottom of the blast furnace and be regularly discharged from the taphole of the blast furnace.

In the joint venture, in order to make use of energy, molten iron is sent directly to the steelmaking plant through ladle.

Because the ironmaking process is a reducing atmosphere, the harmful component-sulfur cannot be removed. In order to ensure the quality of steel, some processes are now equipped with desulfurization processes in front of the furnace of ironworks or steel mills.

At present, there are two kinds of steelmaking process equipment: converter and electric furnace.

Extended data:

Main safety technologies in steelmaking production

(1) Prevention of explosion accident of elbow or reducer. Due to the high flow rate, the local resistance loss of the oxygen pipe elbow or reducer at the upper part of the oxygen lance is large. If there is slag in the tube or the degreasing is not clean, it is easy to induce high purity, high pressure and high speed oxygen explosion. We should improve the design, prevent sharp bends, slow down the flow rate, blow pipes regularly, clean filters and improve degreasing to avoid accidents.

(2) Prevent and control backfire explosion accidents. The negative pressure of oxygen pipe and the blockage of oxygen lance nozzle caused by low pressure oxygen are easy to backfire due to the gas produced by high temperature molten pool, resulting in explosion accidents. Therefore, oxygen pressure should be closely monitored. When using oxygen for multiple furnaces, don't rush to use oxygen, so as not to cause pipeline tempering.

(3) Prevent steam resistance explosion accidents. The backwater of the oxygen lance is blocked due to operational errors, and the accumulated water in the oxygen lance vaporizes at the high temperature of the molten pool, preventing high-pressure water from entering. When the steam pressure in the oxygen lance is higher than the strength limit of the lance wall, it will change and explode.

References:

Baidu encyclopedia-steelmaking

References:

Baidu encyclopedia-steel industry