The heat treatment process usually includes three processes of heating, holding and cooling, and sometimes only two processes of heating and cooling. These processes are interconnected without interruption. This process can be carried out with the aid of a ceramic heat exchanger. The production process of ceramic heat exchangers is basically the same as that of kiln furniture. Thermal conductivity and oxidation resistance are the main application properties of the material. The principle is to place the ceramic radiator near the flue outlet and at a higher temperature without the need for cold air and high temperature protection. When the kiln temperature is 1250-1450 ℃, the flue outlet temperature should be 1000-1300 ℃, the waste heat recovery rate of the ceramic heat exchanger can reach 450-750 ℃, and the recovered hot air is sent into the furnace. The kiln and combustion gas form a mixture, which directly reduces production costs and increases economic benefits.

Ceramic heat exchangers have been well developed under the limitation of the use of metal heat exchangers, because it better solves the problems of corrosion resistance and high temperature resistance, and has become a heat exchanger for recycling high temperature waste heat. After many years of production practice, it shows that the ceramic heat exchanger works well. Its main advantages are: good thermal conductivity, high temperature strength, good oxidation resistance and thermal shock resistance. Long life, less maintenance, reliable and stable performance, easy to operate. Metal heat treatment is a device for recovering waste heat from high temperature flue gas.