A BOILER AND A SUPERHEATER, AS WELL AS A METHOD

摘要

A boiler and a method in a boiler (1) producing thermal energy, the method comprising: combustion or fuel and combustion air in the furnace (2) of the boiler, delimited by walls; receiving of thermal energy by a steam superheater (15) placed on the wall of the furnace and comprising at least one heat exchange surface (21), and supplying of gas or a gas mixture to the front of said heat exchange surface to form a barrier layer (18) for protecting the heat exchange surface from flue gases (19) developed in connection with the combustion. At least one supply device (17) is provided in the superheater or in the direct vicinity of the superheater, to supply gas or a gas mixture to the front of said heat exchange surface to form a barrier layer (18) to protect the heat exchange surface from the flue gases (19) in the boiler. In one example, a supply device matrix is provided in the area delimited by the superheater.