Application analysis and material selection of refractory materials for CDQ furnace
Publish Time: 2020-09-25 Origin: Site
Structural characteristics of CDQ furnace
The main equipment of CDQ is dry quenching furnace masonry, which is cylindrical vertical masonry in positive pressure state. The outer surface of CDQ furnace is surrounded by metal shell, and the inner layer is made of different refractory products. The coke enters the cooling zone from the upper cone of the pre-storage room due to its self weight. The inert gas exchanges heat with the red coke in the cooling zone, and the thermal circulating gas enters the annular air duct from the ramps zone. After entering the primary dust removal chamber, the coke enters the boiler for heat exchange with boiler water to generate steam.
Due to the temperature fluctuation before and after coke charging, the upper cone of the pre-storage room has higher requirements for the thermal stability of the refractory brick masonry. The middle part of the pre storage section is a straight section solid refractory masonry, which mainly bears the thermal expansion after loading red coke and the impact and wear of coke. The lower part of the pre-storage room is an annular air duct, which is divided into two ring masonry of inner wall and outer wall, and the inner wall should bear coke loading Carbon impact and wear, but also to prevent the pre-storage room and annular flue due to the pressure difference caused by the leakage phenomenon.
The ramps zone is the key part of the load-bearing structure of the CDQ furnace. The temperature in the area fluctuates frequently, and the coke entrained by the circulating gas washes the part violently. Therefore, the requirements for the thermal shock stability, wear resistance and bending resistance of the bricks in the ramps zone are very high.
The refractory masonry in the inner wall of cooling zone is mainly subjected to the abrasion of coke falling and moving and the impact of frequent fluctuation of working temperature.
The 1 Dust Catching adopts gravity dedusting method to collect coarse-grained coke powder mixed in the circulating gas from the Annular duct area of CDQ furnace. The arch masonry structure is adopted for the refractory brick at the top of 1 Dust Catching, and the conical bucket structure is constructed by refractory bricks at both sides and bottom parts.
Performance analysis of refractory material for CDQ furnace
CDQ Furnace Parts | Work Environment | Performance Requirements of Refractory Materials |
Upper Cone | Temperature variations Wear heavily | Excellent thermal shock stability Wear-resisting |
Pre-storage Room | High temperature thermal expansion Wear from coke Wear heavily | High temperature resistance low thermal expansion Wear-resisting |
Ramps Zone | Bearing the upper masonry load Temperature changes frequently Circulating gas scour Wear of coke dust | High CMOR Excellent thermal shock stability Erosion resistance Wear-resisting |
Cooling Zone | The largest wear from coke Temperature changes frequently | High Wear-resisting Wear-resisting |
1 Dust Catching (1DC) | Top arch masonry: temperature changes frequently Conical bucket masonry on both sides: wear heavily Conical bucket masonry at the bottom parts: Large scour | Excellent thermal shock stability Erosion resistance Wear-resisting |
Selection of refractory material for CDQ furnace
CDQ Furnace Parts | Refractory Materials |
Pre-storage Room | BN/Clay Mortar |
Annular duct area | AM/Mullite Mortar |
Ramps zone | AT（A Carbide-Silicon-Mullite Brick）/SIC Mortar |
Cooling Zone | Columnar Mullite Wear-resisting brick/BM/Mullite Mortar |
1 Dust Catching (1DC) | AM/AN/Mullite Mortar/Clay Mortar |