Selection of Lattice Brick Material for Regenerative Chamber of Glass Furnace

Lattice body is an important part of heat storage and heat transfer in heat storage chamber. It is required that the lattice brick can withstand high temperature, corrosion resistance, heat storage, heat transfer, and good resistance to cold and heat.

The heat storage effect of a regenerator is usually measured by the heating area of the lattice, that is, the surface area of the lattice that can carry out heat exchange.  The larger the heat storage area is, the more heat is accumulated, the more heat halo is released, so as to fully improve the preheating temperature of air and gas, the more beneficial to fuel combustion.

According to the temperature of the top, upper, middle and bottom parts of the regenerator and the amount of flying materials, different alkaline grid bricks are used.

The top (above 1400°C) due to high temperature, flying material, easy to generate liquid phase with the brick body, so easy to stick flying material and make the brick body stress, therefore, the top of the use of high temperature with excellent creep resistance of zirconium brick or 98% high purity magnesium brick.

The upper part (1000~ 1400*C) has less flying material settlement, and high purity magnesium brick can be used.
In the middle part (800 to 1000°C), there are few flying materials, but it is the sulfate condensation area, which is easy to react with flying materials to form magnesium silicate (MgSiO3). At the same time, SO2 and SO3 formed in the reaction process of nitroso and fuel combustion in the coordination materials are also easy to react with magnesium oxide, resulting in repeated solid liquefaction of magnesium sulfate or magnesium sulfite.  Volume expansion leads to structural damage of magnesite brick, so this part chooses direct bonded magnesite chrome brick (DMC-12) with good thermal stability and low porosity (magnesite chrome brick is not allowed to be used in areas with high environmental protection requirements, and magnesite + magnesite olidine brick is often used).

The temperature at the bottom (below 800°C) alternates between hot and cold, with heavy load and less erosion by alkaline materials. Therefore, materials with good thermal stability and load bearing strength should be used, usually low porosity clay brick (DN-12, DN-13 or DN-15) or sillimanite brick.  If we do not consider the properties of various alkaline bricks and use them in general, it will affect the other lattice when one part of the lattice is damaged, thus reducing the life of the whole lattice.  As most basic firebricks, including magnesia-chrome bricks, contain cracking of one part of the damage will affect other lattice, thus reducing the life of the whole lattice.  As most alkaline firebricks, including magnesium-chrome bricks, contain cracking.