What are the main factors affecting heat transfer in circulating fluidized bed boilers and the law of change? How to solve the problem of water-cooled wall wear

　　Circulating fluidized bed boilers are mainly used in thermal power industry and paper industry. Generally, the rated working pressure of circulating fluidized bed boilers is between 3.8MP and 27.0MPa. Now because of the environmental protection policy, the new circulating fluidized bed boilers are basically supercritical and ultra-supercritical boilers. Today we talk about the main factors affecting the heat transfer of circulating fluidized bed boiler and what is the law of change?

　　What are the main factors affecting the heat transfer of circulating fluidized bed boilers and the law of change?

　　The heat transfer mechanism between the gas-solid two-phase flow in the combustion chamber of circulating fluidized bed boiler and the heat receiving surface can be divided into three parts: gas convection, particle convection and radiation heat transfer from the gas-solid mixture to the heat receiving surface.

　　The heat transfer coefficient of the heat receiving surface has an exponential distribution along the bed height. Along with the change of load in the circulating fluidized bed combustion chamber, the concentration of the material changes along the bed height. At this time, the heat transfer coefficient of the heated surface along the bed height is also changing. The bed temperature increases, the heat transfer is enhanced; the circulation volume increases, the heat transfer coefficient increases. Fluidization speed has less influence on heat transfer of circulating fluidized bed boiler.

　　How to solve the problem of water-cooled wall wear

　　Circulating fluidized bed boiler is probably the most headache for enterprises is the problem of water-cooled wall wear, water-cooled wall wear will cause water-cooled wall leakage burst tube shutdown. Boiler as one of the important production equipment, if the water-cooled wall wear and tear leaking out of the furnace enterprises can not be produced. A power plant, paper mill a day can not start production losses will be huge, so how to completely solve the enterprise water-cooled wall wear is particularly important.

　　In order to help enterprises completely solve the problem of water-cooled wall wear, grille anti-wear was developed and widely promoted and applied. At present, a number of power plants and paper mills at home and abroad are completely away from the water-cooled wall wear problem with the help of grating anti-wear, and realize the long-cycle safe, smooth and economic operation of circulating fluidized bed boilers.