Disclosed are coal falling pipe and circulating fluidized bed boiler

The utility model provides a coal falling pipe and a circulating fluidized bed boiler, which relate to the technical field of thermal energy engineering and chemical engineering and comprise a first pipeline, a second pipeline, a first air supply mechanism, a second air supply mechanism and a third air supply mechanism. The first pipeline is arranged in the vertical direction, and the lower end ofthe first pipeline is connected between the two ends of the second pipeline. The first air supply mechanism is arranged on the other side, opposite to the first pipeline, of the second pipeline; thesecond pipeline comprises a pipeline outlet, and the second air supply mechanism is arranged at the other end, away from the pipeline outlet, of the second pipeline; and the third air supply mechanismis used for supplying air to the joint of the first pipeline and the second pipeline. During specific operation, ventilation is conducted in the second channel through the first air supply mechanism,the second air supply mecha