The invention relates to a method for partial reduction of SO2, wherein a SO2 stream, an oxidant and a gaseous fuel are fed to a burner and reacted in a flame reaction. The burner comprises at least one supply opening for the SO2 stream, at least one supply opening for the oxidant and at least one supply opening for the gaseous fuel, and a burner head (1) with first injection sets (7, 8) and second injection sets (9). First injection sets (7, 8) are arranged in a first section (4) of the burner head (1) and second injection sets (9) are arranged in a second section (5) of the burner head (1). The stoichiometric ratio of SO2, fuel and oxidant supplied through the first injection sets (7, 8) is different from the stoichiometric ratio of SO2, fuel and oxidant supplied through the second injection sets (9). (Figure 1)