​Selection of Refractory Materials for Carbon baking furnace

Selection of Refractory Materials for Carbon baking furnace

A Carbon baking furnace is a device for thermally treating coal, available in rotary and steam models. The choice of refractory materials also differs depending on the type of kiln.

A steam kiln indirectly heats the coal through combustion. The kiln lining is made of sand-lime bricks with good thermal conductivity and a high softening point. A crucible kiln is a heat exchanger kiln. The lining of this kiln is made of high-aluminum ceramic bricks, and special low-porosity clay bricks are used as the lining material. Wear-resistant molds must be used in the burner orifice.

An electrode kiln is a multi-chamber kiln. Since the bottom of the kiln bears the higher load and high temperature, special clay bricks are used as the lining; ordinary clay bricks are not suitable. A carbon calcination furnace is a device for heat treatment of carbonaceous materials in a closed state. This process allows the carbonaceous materials to achieve better antioxidant and anticorrosive properties.

The carbon steam calcination furnace consists of four small crucibles. This furnace fully utilizes the carbonaceous materials by supplementing part of the furnace gas during calcination and burning them in the combustion channel. The combustion channel temperature during calcination is between 1300 and 1380°C. The sand-lime bricks used for the combustion channel of the calcination crucible must withstand high temperatures. They must also be exposed to the impacts of loading and unloading carbonaceous materials onto the crucible walls. They must also be subjected to flue gas erosion and severe slag erosion.

Due to the operating conditions, the lining of the calcination crucible and combustion channel is made of sand-lime bricks. Due to the high temperature of the combustion opening, high-alumina bricks are used for the masonry, while red bricks and lightweight insulating bricks are used for the furnace base. The choice of refractory materials for coal-fired kilns mainly consists of high-load-bearing clay bricks, high-temperature sand-lime bricks, lightweight insulating bricks, and wear-resistant concrete.