Sunrise Refractory Tood you the Efficiently Method of Extend the Life of Magnesium Carbon Brick for Slag Line

Research by Sunrise Refractory Group found that the kiln slag first wets the surface of the magnesia-carbon brick, and then penetrates into the matrix of the magnesia-carbon brick along the pores left after the graphite is oxidized. Erosion and erosion generate low-melting-point liquid phases containing Ca, Si, and Al, thereby gradually eating away magnesite particles.

 

It can be inferred that with the extension of the reaction time, a cementitious structure will be formed in the magnesia-carbon brick, the magnesia particles will be embedded in the liquid phase, and the corners of the magnesia particles will be eroded by the slag and become smooth, thereby making the magnesium-carbon The composition and performance of the brick erosion layer and the original brick layer, especially the thermal expansion coefficient, are very different. When subjected to thermal shock and thermal shock during use, the working surface of the magnesium carbon brick will be peeled off and chipped. Under the conditions of refining outside the kiln, due to the high refining temperature, the viscosity of the slag will decrease, and the interior of the lining will be reduced. The temperature is also higher, and the slag can penetrate into the deeper part of the refractory material to form a thicker reaction layer, which will exacerbate the melting loss of the magnesium carbon brick lining and cause severe peeling and chipping damage. Therefore, the influence of kiln slag on magnesia-carbon brick is mainly manifested by chemical erosion and the resulting poor thermal shock stability, and spalling damage.

In summary, the wetting angle of the two types of furnace slag on the magnesium carbon brick is less than 90 °, which makes it easy to wet the surface of the magnesium carbon brick. When it contacts the magnesium carbon brick, it will accelerate the damage rate of the magnesium carbon brick and low iron The wetting phenomenon of kiln slag is more obvious. In erosion experiments, this phenomenon reduces the corrosion resistance of Mg-C bricks in contact with low iron slag.

 

In order to extend the slag erosion life of kiln magnesium carbon bricks, we can start by adjusting the composition of the slag and increasing the wetting angle of the slag on the magnesium carbon bricks to form a stable slag layer on the surface of the magnesium carbon bricks to prevent surface graphite. Oxidation, inhibit the melting of slag on the surface of magnesia-carbon bricks, or optimize the matrix structure of magnesia-carbon bricks, improve the introduction form and amount of graphite in magnesia-carbon bricks, and adjust the composition of the matrix, thereby affecting the magnesia-carbon bricks. The number, size, shape, and distribution of pores formed by carbon oxidation during use extend the service life of magnesium carbon bricks in the slag line of the kiln.