In modern industrial production, refractory brick, as a key refractory material, is widely used in the construction and maintenance of various high-temperature furnaces, which provides a solid guarantee for the stable operation and efficient production of industrial furnaces. This paper will introduce the application scope, advantages and precautions of refractory bricks in detail to help readers better understand the importance of refractory bricks in industrial production.

I. Scope of use of refractory bricks

Refractory bricks are widely used, covering many industrial fields. In the iron and steel manufacturing industry, refractory bricks are used for lining of blast furnace, hot blast stove, ladle, ladle, heating furnace and other equipment, which can withstand the erosion and mechanical impact of high-temperature molten metal. For example, in a blast furnace, refractory bricks can resist the high temperature corrosion of molten iron and slag, and prolong the service life of the blast furnace. In the non-ferrous metal smelting industry, refractory bricks can be used in melting furnaces, refining furnaces, reverberatory furnaces and other equipment to resist the chemical erosion of non-ferrous metal melt. For example, in the reverberatory furnace of copper smelting, refractory bricks can withstand the high temperature and chemical corrosion of copper liquid, ensuring the smooth smelting process.

In the building materials industry, firebrick is an important part of cement kiln, glass kiln, tunnel kiln, ceramic kiln, lime kiln and other equipment. Taking the cement kiln as an example, the refractory bricks can withstand the high temperature and chemical erosion during the firing process of cement clinker and ensure the normal operation of the cement kiln. In the field of energy and incineration, refractory bricks are used in coke ovens, boilers, fluidized bed boilers, electric furnaces, garbage incinerators and other equipment, which can withstand the erosion of high-temperature flames and smoke. For example, in a garbage incinerator, refractory bricks can resist the erosion of high-temperature flue gas and corrosive gas produced by garbage incineration, and improve the operating efficiency and environmental protection performance of the incinerator.

In addition, refractory bricks are also used in civil fields, such as domestic fireplaces, pizza oven and outdoor ovens. These civil stoves usually need refractory bricks to withstand high-temperature flames, while maintaining the structural stability and safety of the furnace body.

II. Advantages of refractory bricks

Refractory bricks can be widely used in many fields, mainly due to their excellent performance advantages.

(1) High temperature tolerance

Refractory bricks can remain stable at extremely high temperatures, and their fire-resistant temperatures range from 1580°C to 1850 C. For example, the refractory temperature of high-alumina brick can reach 1850°C, which can keep the structure intact in extremely high temperature environment without melting or deformation. This high-temperature tolerance makes refractory bricks an ideal material for lining of high-temperature furnaces, which can effectively protect the structure of furnaces and prolong the service life of equipment.

(2) Corrosion resistance

Refractory bricks have excellent corrosion resistance and can resist the erosion of various chemicals. Whether it is acidic, alkaline or neutral slag, melt or flue gas, refractory bricks can withstand their chemical effects. For example, in a glass kiln, refractory bricks can resist the chemical erosion of glass melt and ensure the normal operation of the glass kiln. This corrosion resistance enables refractory bricks to work stably in a complex chemical environment for a long time, reducing equipment damage and maintenance costs caused by chemical erosion.

(3) Wear resistance

In high-temperature furnaces, the scouring of burden, slag and high-temperature airflow will cause serious wear on lining materials. Refractory bricks have good wear resistance and can effectively resist these mechanical wear. For example, in a cement kiln, refractory bricks can withstand the impact and wear of the burden during the firing process of cement clinker and maintain the integrity of the lining. This wear resistance not only prolongs the service life of refractory bricks, but also improves the operation efficiency of furnaces and kilns and reduces the downtime and maintenance time caused by wear.

(4) Thermal shock resistance

Refractory bricks can keep the structure stable when the temperature changes sharply, and will not crack or peel off. This thermal shock resistance enables the refractory bricks to work normally in the process of starting and stopping the furnace and under the condition of large temperature fluctuation. For example, in an electric furnace, refractory bricks can withstand the rapid temperature change caused by arc heating, ensuring the stable operation of the electric furnace. This performance is very important to improve the reliability and safety of the furnace.

(5) high dimensional accuracy

Refractory bricks have high dimensional accuracy and can ensure the close fitting of furnace lining. Precise dimensions enable the refractory bricks to better adapt to the shape and structure of the furnace, reduce gaps and cavities, and improve the integrity and sealing of the furnace lining. This is of great significance to improve the thermal efficiency and operational stability of the furnace.

III. Matters needing attention in the use of refractory bricks

Although refractory bricks have many advantages, some matters need to be paid attention to in the process of use to ensure that their properties are fully exerted and their service life is prolonged.

(1) Correct selection of refractory brick type

Different types of refractory bricks are suitable for different working conditions. When selecting refractory bricks, it is necessary to choose the appropriate refractory brick type according to the temperature range, chemical environment, mechanical load and other factors of the furnace. For example, for furnaces with high temperature and strong chemical erosion, high alumina bricks should be preferred; For furnaces with low temperature but high wear resistance requirements, clay bricks can be selected. In addition, it is necessary to consider whether the size and shape of refractory bricks meet the design requirements of the furnace.

(2) Standard construction

The construction quality of refractory bricks directly affects its service effect and service life. In the process of construction, the operation should be carried out in strict accordance with the construction specifications. First of all, it is necessary to ensure that the basic structure of the furnace is flat and firm, and provide good support for the masonry of refractory bricks. Secondly, when laying refractory bricks, it is necessary to ensure that the gaps between bricks are uniform and tight, so as to avoid too large or too small gaps. Excessive gap may lead to furnace charge or slag entering the gap, resulting in the damage of refractory bricks; If the gap is too small, it may affect the thermal expansion of refractory bricks and lead to cracking of brick bodies. In addition, the construction personnel should have professional construction skills and experience to ensure the construction quality.

(3) Reasonable oven drying

Before the newly-built refractory brick kiln is put into use, reasonable baking operation is needed. The purpose of the oven is to gradually discharge the moisture in the refractory brick, at the same time, make the brick body adapt to the high temperature environment during the process of gradually heating up, and avoid the brick body from cracking or peeling due to the rapid temperature change. The baking process should be carried out in strict accordance with the baking curve, and the heating rate and holding time should be controlled. For example, in the drying process of cement kiln, it usually needs to go through three stages: low temperature drying, medium temperature drying and high temperature drying, and each stage has strict requirements on heating speed and heat preservation time. Reasonable baking operation can effectively prolong the service life of refractory bricks and improve the operation stability of furnaces.

(4) Regular maintenance and inspection

During the operation of the furnace, the refractory bricks should be maintained and inspected regularly. Regular inspection can find the damage of refractory bricks in time, such as cracks, peeling and wear. For minor damage, it should be repaired in time to prevent further damage. For example, for cracks on the surface of refractory bricks, refractory mud can be used to repair them. The severely damaged refractory bricks should be replaced in time to ensure the safe operation of the furnace. Regular maintenance and inspection can not only prolong the service life of refractory bricks, but also find potential safety hazards in time to ensure the normal operation of furnaces.

IV. Conclusion

As an important refractory, refractory brick plays an irreplaceable role in the construction and operation of industrial furnaces. Its excellent high temperature resistance, corrosion resistance, wear resistance, thermal shock resistance and high dimensional accuracy enable it to meet the needs of various complex working conditions. However, when using refractory bricks, it is also necessary to correctly select the brick type, standardize the construction, properly bake the furnace and regularly maintain and inspect it, so as to give full play to its performance advantages, prolong its service life and provide reliable guarantee for industrial production. With the continuous development of industrial technology, the performance and application scope of refractory bricks will also be continuously improved and expanded, making greater contributions to the efficient operation of industrial furnaces and kilns and energy conservation and emission reduction.