1. Several problems in the design of tail flue of circulating fluidized bed boiler;
The main performance is that although the circulating fluidized bed boiler is equipped with a cyclone separator, the concentration of fly ash that the separator failed to collect and entered the tail flue is still high, reaching 4kg/m3. Because the separator efficiency deviates from the design efficiency in actual operation, more large particles enter the tail flue, which leads to great wear strength and increases the wear degree at this position.
2. Influence of tube bundle design structure:
According to relevant data, the wear of staggered tube bundles in the second row is about 2 times larger than that in the first row, and the wear in the same row is smaller than that in staggered rows. The local wear of the first row of in-line and staggered tube bundles is basically similar, ranging from θ = 45 to 60, while the local wear of the second row of staggered tube bundles ranges from θ = 30 to 45. The larger the particle size, the smaller the θ angle.
3, high flue gas velocity:
According to the experiment, the wear rate is directly proportional to the n power of particle velocity. If the flue gas velocity is equal to the dust particle velocity, then n=3. The higher the flue gas velocity, the higher the dust particle velocity, which leads to the increased wear of the heating surface at the tail of circulating fluidized bed boilers such as economizer.