The  circulating fluidized bed boiler is mainly composed of three parts of combustion system of equipment, gas-solid separation recycling equipment and convective flue, of which, the combustion equipment includes air chamber, air plate, combustion chamber, the hearth of boiler, fuel oil and coal feeding system and so on; Gas-solid separation circulation equipment includes two parts of material separation devices and returns unit. The convective flue includes the heating surface of superheater, reheater, economizer and air preheater etc.(lsh)