Selection of Refractory Materials for Rotary Kiln

Rotary kiln is the key equipment for hazardous waste treatment and is widely used in the domestic hazardous waste treatment industry. The quality of rotary kiln refractories affects the stable operation of rotary kiln. The selection and maintenance of rotary kiln refractories in hazardous waste treatment are analyzed for reference in specific engineering applications.

Incineration of hazardous waste in a rotary kiln usually requires several stages such as drying, pyrolysis, burning, and combustion. After these stages, the harmful components in the hazardous waste are fully decomposed and destroyed at high temperatures, forming high-temperature smoke and slag. These high-temperature fumes and slag can cause erosive damage to the refractories built in the rotary kiln.

Therefore, the rotary kiln refractories used for hazardous waste incineration should have the following characteristics:

1. High temperature resistance. It can operate for a long time in a high-temperature environment above 800 °C.

2. High strength and excellent wear resistance. In order to withstand the expansion stress at high temperatures and the stress caused by the deformation of the rotary kiln shell, the refractory material in the rotary kiln needs to have a certain mechanical strength.

3. Good chemical stability and thermal stability to resist the corrosion of chemical substances in the flue gas, and can withstand the alternating thermal stress in the combustion state.

4. Good thermal expansion stability. Although the thermal expansion coefficient of the rotary kiln shell is greater than that of the refractory material of the rotary kiln, the shell temperature is generally around 150-300°C, but the temperature of the refractory material is generally above 800°C, which may cause the thermal expansion of the refractory material to be greater than that of the rotary kiln shell Body, easy to fall off.

5. Low porosity. High porosity will make the flue gas easily penetrate into the refractory material and corrode the refractory body.