Applications of corundum bricks in the petrochemical industry

Corundum bricks have an alumina content ≥90%, a refractoriness exceeding 1790℃, a dense structure, high high-temperature strength, and are resistant to corrosion from reducing gases such as hydrogen and carbon monoxide. They are also resistant to erosion and penetration by oil and gas media, making them a core lining material for high-temperature and high-pressure petrochemical units, suitable for harsh operating conditions of 1200-1500℃.

1. Linings for synthetic ammonia converters and coal gasification furnaces

First-stage and second-stage converters withstand long-term high-temperature, high-pressure, and strong reducing gas flows at 1300-1450℃. High-purity corundum bricks resist hydrocarbon and water vapor erosion, preventing lining spalling and gas leakage. Chromium corundum bricks are used as the working layer in coal-water slurry and slag-oil gasification furnaces to resist the erosion of high-temperature molten slag and high-speed gas flows, reducing the frequency of unplanned unit shutdowns.

2. Radiation section, furnace bottom, and furnace tube support for ethylene cracking furnaces

The temperature in the radiation zone of the cracking furnace is 1000-1250℃, and the flue gas contains sulfides and hydrocarbon media. Corundum-mullite bricks possess both high-temperature resistance and thermal shock resistance. Used in furnace walls, furnace bottoms, and irregularly shaped support bricks, they protect furnace tubes from high-temperature deformation and media corrosion, ensuring stable pyrolysis reactions.

3. Wear-resistant lining for catalytic cracking cyclone separators and flues

Oil and gas carrying catalyst particles erode the inner walls of equipment at high speeds. Corundum bricks, with their high Mohs hardness and wear resistance far exceeding high-alumina and clay bricks, are used in separator cones, inclined tubes, and high-temperature flue bends to reduce wear and perforation, extending equipment lifespan.

4. Lining for high-temperature sections of carbon black reactors and heating furnaces

The reaction zone of carbon black furnaces experiences extremely high temperatures and highly corrosive acidic flue gas. Corundum bricks, with their strong chemical stability, are not easily reacted with the media. In various tubular heating furnaces, corundum bricks are used to line the high-temperature furnace chamber and burner perimeter to isolate the high-temperature flame and prevent ordinary refractory materials from softening and cracking.

Compared to ordinary refractory bricks, corundum bricks are suitable for the complex high-temperature and corrosive environment of petrochemical plants. Although the cost is relatively high, the overall operation and maintenance cost is lower over a long period of operation. They are an indispensable high-temperature refractory material for modern large-scale refining and fertilizer plants.