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The use environment of refractories is quite complex, and different use environments put forward different requirements for refractories. In this section, we comprehensively analyze the general requirements of refractories in the use environment. Usually corresponding to each use requirements have a corresponding refractory performance corresponding to it.

1, resistance to temperature damage. In the process of use, the refractory will not melt or soften the material, which will lead to the destruction of the kiln structure or refractory components. The corresponding properties include refractoriness, load softening temperature, creep resistance at high temperature and high temperature strength.

2, resist the damage of thermal stress. In industrial kilns with batch production, the lining or refractory components repeatedly undergo the process of heating and cooling, the so-called "thermal shock". Even in non-intermittent, temperature-stable kilns, there is a large temperature difference between the hot and cold sides inside the refractory, both of which cause greater stress in the material. The magnitude of stress is related to the thermal conductivity, expansion coefficient, elastic modulus, strength and many other properties of the material. The related refractory can be used for thermal shock resistance.

3, resist the erosion of environmental media. Refractory materials in the use of the process is often inevitable to contact with the relevant media, such as metallurgical slag, molten metal, molten glass, cement clinker, molten coal slag and corrosive gases. At high temperatures, the refractory will be corroded when it comes into contact with these media. In addition, these media will also penetrate into the interior of the refractory along the pores and cracks of the refractory, causing the destruction of the internal composition and structure of the material. The composition and structure of refractories are the factors that affect the corrosion resistance of refractories. The corresponding serviceability is slag resistance.

4, does not pollute the bearing product. Refractory materials are used as containers that carry some molten or sintered products at high temperatures, industrial furnace linings or ceramic carriers used at high temperatures, such as ladles and tundish in the iron and steel industry, linings of glass tank kilns, and bearing plates (shed plates) and saggers for firing ceramic and electronic materials. If the refractory reacts with molten steel and glass solution, it will increase the content of impurity elements and inclusions in molten steel, forming stones or streaks in the glass. If the sintered electronic material reacts with the sintered electronic material, the bonding phenomenon will be caused, which will affect the surface roughness and other properties of the electronic material. In recent years, due to the rapid development of high-quality steel, the pollution of refractory materials to molten steel has been paid attention to. It is a noteworthy direction to study the pollution and possible purification effect of refractory materials on molten steel.

5, do not pollute the environment. Refractory materials in the production and use of the process should not cause harm to the human living environment, do not produce harmful substances that pollute the atmosphere, water sources, as far as possible to facilitate the recycling of materials. In recent years, the development and research of magnesia-chromium refractory replacement products is a good example. Magnesium-chromium refractory is a kind of widely used high-quality refractory, but due to the harm of hexavalent chromium to the human body, especially the pollution of water sources, magnesium-chromium refractory has been included in one of the varieties that should be eliminated, and new alternative products are being actively developed. When discussing the environmental impact of refractory production, it is also necessary to mention energy consumption and the impact of CO2 on climate. A large number of non-fired or amorphous refractory materials, the use of high temperature under the conditions of use to complete its necessary physical and chemical processes, to meet the requirements of use, the so-called "adaptive", to reduce the energy consumption of refractory production is of great significance. At present, although the share of amorphous refractories and non-fired refractories in refractories is not small, but the theoretical research on the application of refractory adaptive process is still weak, hindering the development of amorphous refractories and non-fired products. In addition, refractory materials are used in high-temperature furnaces, and refractory materials should play a certain role in the energy saving and emission reduction of industrial furnaces. Thermal insulation refractories with high thermal insulation properties and thermal insulation refractories that can be directly used on the hot surface or can be directly in contact with the melt are particularly important for the energy saving of various kilns and high temperature containers.