Abstract: Taking the project of 2×350MW thermal power unit of Datang Linzhou Thermal Power Company Limited as example, the fundamental principles of the pneumatic ash handling system was introduced. According to the practical operation curves, the application of the pneumatic dense phase ash handling system with internal bypass was analyzed. Aiming at the problems existing in operation, the solutions were given, which can be used as reference for design and application of the system.

Key words: tube in tube, pneumatic ash handling, designed capacity, pressure in conveying pipe, ash gas ratio, curve of ash handling system