Damage Mechanism And Gunning Ceramic Glaze Coating, Coke Oven Coking Chamber Walls

According to present situation which has obviously affected the lifetime of coke oven that furnace gas leaking , difficulty of coking coal pushed and dropping of silica bricks caused by damage of coking chamber or serious carbon deposit of coke oven which has been running 20 years or so, damage situation of silica bricks of coking chamber was studied and the spraying ceramic coating on the wall of coking chamber was used. By studying the damage of silica bricks in relation to irregular microstructure caused by leakage of gas and carbon deposit in pores and flaws was discovered. When the temperature having been changed expansion and contraction in different area caused by different thermal expansivity of silica bricks and carbon was happened, which caused flaws.According to the damage mechanism of silica bricks, the spraying ceramic coating was invented. The application of the ceramic coating has not only prevented carbon deposit in pores and flaws, but also caused the ceramic coating bearing compressed stress which could effectively prevent crack propagation and cause crack blunting and branching on the border. Ceramic coating can overflowing the cracking and flaws in silica bricks. According to the priority and deficiency of the spraying technology, the dry spraying technology was used. The high temperature of coking chamber was used by the powder to adhere to it in a very short time. To execute it, the powder was consisted of different particle size, and part of raw material was micropowder. The fusing agent was also used. The pressure and angle of the spaying must be pay more attention to. By calculation the high temperature of coking chamber can be used by the coating powder to adhere to it in a very short time.By testing the properties of coated bricks, the porosity and carbon deposit abated. The porosity decreased from 15mm of not-coated bricks to 0.5~3m. The abrasive resistance of coated bricks is obviously raised compared with not-coated bricks. The abrasion of silica bricks decreased from 0.43g of not-coated bricks to 0.023~0.076g of coated bricks. The thermal shock resistance of coated bricks obviously raised. The cracking sequence changed from 1~2 sequence of not-coated bricks to 15~30 sequence of coated bricks.