Discussion on the current situation of coking prevention and control technology of boiler heating surface of coal-fired power station

With the promotion of low-nitrogen combustion technology and the mixing of high-alkali coal represented by Zhundong coal, the coking problem of heating surface of coal-fired boilers such as water wall and superheater is becoming increasingly prominent, which seriously affects the safe and stable as well as economic operation of the units. The formation and development of coke involves complex physicochemical interactions. The mechanism, influencing factors and treatment measures of coke have been extensively studied at home and abroad. Besides controlling the coal quality, optimizing the boiler design and adjusting the boiler operation, the preparation of anti-coking coating is also an important technical path to realize the prevention and control of coking on the heating surface. In the process of coating design and preparation, on the basis of meeting the anti-coking performance requirements, the coatings need to combine appropriate high temperature resistance, wear resistance, corrosion resistance, heat transfer property and other properties.