The invention relates to a blow-in nozzle (1) for introducing a medium into a gas stream (5). In the region between an inner nozzle chamber (8) and the nozzle inflow opening (11) there is formed a swirl chamber (13) with a baffle plate (14) lying approximately opposite the inflow opening, the nozzle chamber (8) being radially offset with respect to the inflow opening (11). The medium (7) to be introduced into the gas stream (5) is therefore initially distributed within the blow-in nozzle (1) uniformly over the cross-section of the nozzle chamber (8), so that it can then be blown into the gas stream in fine distribution over a very large cross-section. <IMAGE>
