What are the main technical measures to prevent the abrasion of circulating fluidized bed boilers?

The inherent characteristics of circulating fluidized bed boiler determine that equipment wear is inevitable. In order to ensure the long-term safe and stable operation of the boiler, the main technical measures are as follows: ① selecting suitable anti-wear materials and reasonably designing the structure of wearing parts; (2) Special treatment technology for metal surface, increasing protective layer and reasonable construction. Circulating fluidized bed (CFB) boiler is a new type of combustion equipment developed in China in recent years, and the development of CFB combustion technology is advancing by leaps and bounds with its high efficiency and low pollution. Today, with the increasingly stringent environmental protection requirements, CFB boilers have become the most promising combustion equipment at present. However, compared with other boilers, CFB boilers wear more seriously. In engineering, wear is usually understood as an unexpected gradual change of material surface due to particle peeling caused by mechanical reasons (such as thinning and cracking). The common wear of boiler is the change caused by high-speed ash particles scouring from different angles and colliding with the furnace wall or heating surface. Some data show that the wear amount is directly proportional to the 3.22 power of smoke velocity, and increases with the increase of ash particle concentration. Theoretically, reducing wear should start with reducing flue gas velocity, ash particle concentration and particle size. Because of the large particle diameter and high material concentration, the bed combustion chamber has the most serious wear on the furnace wall. If the air chamber and bed are non-water wall structures, the thermal stress and material wear caused by the thick furnace wall will often lead to the falling off and cracks on the inner surface of the wall. This problem is well solved by replacing the square corner with fillet, because the cross-sectional shape of the corner has changed, which leads to the formation of vortex zone in the flue gas and accelerates the wear of the pipeline. We follow the trend and make the furnace wall at the lower part of the water cooling wall with the same cross section as the membrane wall, so that there is no cross section change in the vertical direction.