Adding method of carbonless brick bond

Carbon free brick is made of high aluminum or corundum particle material, high aluminum or corundum powder material, magnesium oxide particle or powder material, which is combined into a certain shape and volume of firebrick with a composite binder.

At present, resin and magnesium salt are generally used as bonding agents for non-carbon brick lining of ladle at home and abroad. Although the carbon-free brick made of resin as a bond has a high compressive strength at room temperature, the strength decreases due to decarbonization and oxidation at high temperature, and the carbon-free brick made of carbon-free raw materials still contains 1.5 2.5% carbon due to the addition of resin.

The principle of coagulation and hardening of magnesium salt solution as a bond of carbon-free brick is mainly caused by the reaction of magnesium chloride (MgCl2*6H20) with magnesium oxide to produce magnesium oxychloride, and the rapid and continuous hydration of magnesium oxyoxide to produce Mg(OH)2 due to the presence of magnesium chloride. The reaction is MgO+ MgCl2+H20 ^ xMgO y MgCl22H20

MgO +H20 ~~ Mg(OH)2

The hydration reaction between water and MgO in aluminum-magnesium refractory is originally relatively slow, but when there is MgCl2 in the water solution, it can accelerate the dissolution of Mg(OH)2, thus promoting the continuous hydration of MgO, promoting the formation of Mg(OH)2 and becoming a continuous crystal skeleton structure, so that the strength of the combination can be improved. Mg(OH)2 in pubic 0. When C or so is decomposed, it becomes a highly dispersed MgO with quite high activity. This product can promote solid phase sintering and make sintering easy.

It can be seen that the carbon-free brick with magnesium salt solution as the binder has good high temperature performance and high temperature strength, and the carbon content is less than 0.1%, but the magnesium salt solution as the binder has the disadvantages of low compressive strength at room temperature.