Application Scope of Refractory Materials -2

2: Ironmaking system

The ironmaking system includes sintering, coking, blast furnace and its ancillary equipment. The ignition furnace of the belt sintering machine is made on site with refractory plastic and clay combined Refractory castables, or lifted with prefabricated blocks of phosphoric acid Refractory castables, with a service life of 3-6 years.

When using a linear ignition device, there is more pressure on the top of the furnace, and the working conditions of the furnace become better. Lightweight and high-strength refractory castables or refractory fibers and their products can be used as lining, and good results can also be achieved;

The top insulation layer, covering layer, and furnace door of the coke oven are poured with refractory castables. When the furnace head is damaged, it is repaired with spray paint. In addition, the dry quenching equipment also uses heavy or lightweight refractory castables;

A blast furnace is a continuous production ironmaking equipment. Small blast furnaces were once built using prefabricated blocks made of aluminate cement and high alumina phosphate refractory castables, but now they are commonly built using resin bonded aluminum carbon unburned bricks.

The water-cooled walls of large blast furnaces are rammed with silicon carbide castables, while the bottom cushion layer and surrounding brick joints are filled with refractory castables and silicon nitride fillers. When the lining is damaged, refractory pressed materials and refractory spray coatings are used to repair it, in order to extend its service life and achieve a furnace life of 10 or even 15 years.

The blast furnace tapping hole is generally blocked with dispersed Al2O3-SiC-C gun mud, which can ensure stable tapping and normal operation.

The blast furnace tapping ditch was originally made of refractory ramming material, with a per ton iron consumption of approximately 1.1kg. Now, using low porosity dense refractory materials for casting, the one-time iron throughput reaches about 100000 tons, and the cumulative iron throughput of the first generation of trench age is about 900000 tons. The unit iron consumption per ton of refractory materials is less than 0.38kg. At the same time, self flowing refractory castables and non baking refractory castables have also been applied on the iron tapping hook of blast furnaces. Hot blast furnaces are key auxiliary equipment of ironmaking blast furnaces.

The lining of small and medium-sized blast furnace hot blast furnaces is constructed with prefabricated refractory castable blocks. The burner of the hot air stove can be built with prefabricated refractory castable blocks or poured on site, and the working lining of the ball top can be poured with castable. The body of a large hot blast stove is adjacent to the first layer of lightweight spray coating with a volume density of about 1.3g/cm3 on the furnace shell, and a layer of acid resistant spray coating is sprayed on the top of the ball to form an overall lining. Materials such as corundum refractory castable are used for on-site pouring, and good usage effects are achieved; Torpedo type molten iron tanks and mixed iron furnaces generally use partially or entirely refractory castable materials, and can also be repaired with refractory spray coatings, resulting in better usage effects.