What are the main factors affecting the wear of the water wall in fluidized bed boilers?

It’s mainly the scouring by particles in high-temperature cycles, I guess

The main factors affecting the wear of the water wall are as follows: 1. Influence of flue gas flow velocity: The higher the flue gas flow velocity, the more severe the wear, and the wear amount is proportional to the cube of the flue gas flow velocity. The greater the primary air flow, the greater the wear. Furthermore, the greater the amount of secondary air, the more severe the disturbance to the combustion process inside the furnace, and the greater the wear on the water wall as well. 2. Influence of flue gas particle concentration: The higher the particle concentration in the flue gas, the greater the wear on the water wall. Because the larger the number of particles, the more intense the impact and erosion on the pipe wall. During the operation of a circulating fluidized bed boiler, the higher the load, the greater the bed density and the bed differential pressure, which indicates a higher particle concentration and thus greater wear. Due to its specific combustion method, the density of solid materials in a circulating fluidized bed boiler is several dozen to over a hundred times that of a coal powder boiler. 3. Influence of fuel properties: The greater the hardness and ash content of the fuel particles, the stronger the cutting effect on the walls of the water-cooled tubes, resulting in greater wear. Especially when coal gangue or other high-hardness fuels are used in combustion, it **reduces the operating time before the water wall tubes burst. 4. Impact of installation and maintenance quality: Poor quality in the installation and maintenance of boilers can lead to issues such as incomplete welding of the heating surface fins, which results in the leakage of numerous particles and causes wear on the sides of the water wall tubes. Or, a large number of raised areas remaining on the surface of the tube panel after welding can cause particle eddies that increase wear. 5. Wear of wear-resistant materials: The pipe walls at the slag discharge ports, secondary air inlets, and coal feeding ports in the dense phase region of the furnace can suffer wear due to the detachment of wear-resistant materials. At the return air inlet of the wind-water combined cooling fluidized bed slag cooler, excessive wind speed blows away the wear-resistant material, resulting in wear. 6. Influence of the boiler’s own power field: Due to the uneven distribution of smoke flow velocity inside the furnace, the smoke flow velocity at the corners is much higher than that in the middle, resulting in more severe wear there compared to other areas.