Method for combusting a solid phase fuel, where the fuel is caused, by the help of a non-pneumatic feeding element (11), to be fed to an inlet opening (11a) in a burner device (10) having a first inlet (13a) for the oxidant through which an oxidant is caused to flow via a first supply conduit (13). The first inlet (13a) for oxidant is caused to be arranged in the form of an opening surrounding the inlet opening (11a), in that the oxidant is caused to flow out through the opening (13a) with a velocity of at least 100 m/s, through a burner pipe (16) and out through a burner orifice (17) to a combustion space (18), so that the oxidant by ejector action causes the fuel to be conveyed through the burner pipe (16) and out through the burner orifice (17).