Overfiring air port, method for manufacturing air port, boiler, boiler facitily, method for operating boiler facility and method for improving boiler facility

摘要

An overfiring air port (100) of the present invention is to supply an incomplete combustion region with air making up for combustion-shortage, in a furnace in which the incomplete combustion region less than stoichiometric ratio is formed by a burner. Furthermore, the airport is characterized by comprising: a nozzle mechanism for injecting air including an axial velocity component of an air flow and a radial velocity component directed to a center line of the air port (100) ; and a control mechanism for controlling a ratio of these velocity components.