Silica Mortar Used In the Coke Oven

Silica mortar is a type of monolithic refractory formulated with a certain proportion of silica refractories, additives and binders. It is mainly used as a joint material or a coating material in the coke oven, glass furnace, acid steel-making furnace and other thermal equipment. 

When used as a joint material, its quality has a great effect on the quality of masonry. It can adjust the size error and irregular shapes of bricks to make the masonry neat and the load balance. It can also make the masonry a strong and tight whole to resist the external damage and prevent the intrusion of gases and melt.

 

When used as a coating material, its quality has great impact on the protective layer and the service life of the masonry. So, mortar should have good flowability, plasticity, adhesion and stability. 

 

Silica mortar used in the coke oven can be divided into three generations. The first generation was developed before 1970s. It is formulated with silica powder, sand powder and soft directly bonded clay in a certain proportion. But, this generation has poor workability and the saturation of ash is difficult to guarantee. The second generation was developed during 1970s and 1980s. This generation is formulated with natural silica sand or earth and soft bonded clay in a certain proportion. Sometimes, additives are added. It has good workability, has low requirements on the technical level of the construction workers and can ensure the saturation of ash. But it does not bond with silica bricks. After 1980s, the third generation emerges. It is made of natural silica earth or sand and soft bonded clay. It has high requirements on the softening temperature under load and the bonding strength. To improve its workability, some additives can be added. It can greatly reduce the leakage rate, increase the bond strength and prolong the service life of the oven. 

 

But with the increasing scale and complexity of coke ovens, the previous mortars have shown insignificancy. More and more new silica mortar recipes have been developed to meet requirements.