Recycling Method of Waste Refractory Bricks in Steelmaking

In this case,

Recycling Method of Waste Steel refractory brick

In the monthly production of 900t steelmaking waste bricks, there are 250t can not be selected points and can only be abandoned; there 650t can choose points and clear composition, easy recycling. To this end, the following two aspects of development: a) waste brick as raw materials, that is, as a smelting, refining

B) the waste brick classification, mashing processing, adjust the composition and particle size and then used as refractory, including the used SN skateboard Ladle Permeable Brick, electric furnace waste brick regeneration (repair) technology, there will be waste Bricks are used as raw materials for indeterminate shapes (castable and pounding materials, etc.).

In this case,

Direct recycling of waste bricks

1 for LF ladle refining slagging material

In the LF refining of molten steel, CaO (lime) and CaF2 (fluorite) are added to the ladle for desulphurization (S) of molten steel and trapping of floating inclusions from the molten steel. Of the melting loss of MgO in the firebrick refractory sale melt, to be added to the residue containing MgO

Light burning dolomite.

Therefore, the choice of containing MgO-C, Al2O3-MgO-C and other components of the steel waste high insulating brick as a substitute for light burned dolomite. The CaO content of the waste brick is lower than that of the light burned dolomite, but contains about 30% Al2O3 and low SiO2 content (only 3.5%) which reduces slag basicity.

The experimental results show that: (1) The waste brick is used as LF ladle refining slagging material,

A) Compared with the light burned dolomite, the waste slag contains Al2O3, even if the amount of large, slag viscosity increase is small, and will not reduce the slag off the S capacity, it can reduce the slag agent CaF2 addition;

B) When the amount of waste brick used as slagging agent reaches ≥3kg / t steel, the amount of molten MgO in the slag can be controlled to a saturation of ≤100kg / furnace. With such a good effect, and now waste refractory brick for sale has been the full amount of recycling for slagging agent.

2 for electric furnace melting slagging agent

Stainless steel (referred to as SUS) is the furnace after the initial refining by argon oxygen decarburization (ie AOD) furnace refining. In the electric furnace smelting, in order to ensure the slag basicity and improve Cr yield, lime (CaO) slag should be added. Therefore, the choice of AOD furnace used dolomite waste brick instead of lime for slagging. The main components of waste brick is 59% MgO, 39% CaO, 0.8% SiO2. The results show that MgO can be effectively restrained from melting (ie, the melting loss of lining brick) in refractory materials. When the dosage of waste dolomite brick reaches 1.5t / furnace, MgO

The number of non - waste brick by the slag when the 100

And the amount of Cr2O3 in the slag can be controlled to a low level so as to improve the yield of Cr. In addition, the addition of waste brick will not cause the molten steel boiling, but also not because of the slag basicity of the impact of molten steel off S.

As the amount of dolomite waste brick with AOD furnace dolomite brick increase in the amount of increase, it is now all the dolomite waste brick for SUS melting slagging agent.

In this case,

Recycled waste bricks are used as raw materials

The Regeneration of Skateboard for Ladle

Ladle slab is installed in the bottom of the ladle to control the amount of molten steel out of the plate-like refractories. The loss includes wear loss caused by scouring in the molten steel at the hole (0.5mm reaming speed) and the sliding friction between sliding blocks (the maximum wear rate of the sliding surface is 1.7mm / furnace times) due to skid brick surface cracks less, so long as the holes on the brick and sliding surface repair can be fully regenerated. In recent years, based on the progress of refractory material regeneration technology, SN slippery bricks were experimentally regenerated.

Regeneration of electric furnace brick

Steelmaking waste brick should not only be used as LF and electric furnace slagging material, and should have a higher value-added development, the recycling of recycled. To this end, must be removed from the surface of waste brick attached to the slag, steel. But in fact the electric furnace used MgO-C, MgO waste brick surface attachment Slag, steel less easy to select points. Therefore, the bricks that were re-made as the main raw materials were used in the low heat load of the electric furnace, and the experimental study was carried out.

The apparent porosity of the regenerated bricks and new bricks were 81% and 84%, respectively, and the C contents were 13% and 12%, respectively. The apparent porosity was 5.1% and 4.0%, the specific gravity was 2.83 and 2.80, The compressive strengths were 50 and 40 MPa, respectively. Therefore, the physical and chemical properties of the base

This is quite. The two brick are used in electric furnace slag line part of the real furnace test showed that the new brick erosion rate index of 100, and recycled brick of 110, which is basically the same corrosion resistance.

Now, MgO-C recycled brick has been applied to the electric furnace vault; and is expanding its application to other parts.

3 is used as an unshaped refractory

As a method for recycling waste refractory materials, it has been studied as a castable material and a milled material. Due to the combination of unmodified refractory composition, particle size, binder was adjusted to obtain the necessary corrosion resistance and adhesion.

When recycling recycled products, the use of unshaped refractories to study the use of high-frequency ladle in the package: the cladding when not attached to the refractory material into the Al2O3 series of mashed goods, try to use it for ladle heat Low load and non-severe erosion sites, such as ladle trunnions and

Above the site, including the end of the package and the wall corner parts. Although the composition of recycled material and original material is different (such as SiO2 content of 4% and 3%, respectively), but in the rotary erosion test, the amount of slag erosion is basically the same, it can be fully used.

Now, the proportion of recycled materials in different parts of the ladle has reached 50% -100%.