A device for thermal treatment of corrosive gases includes a chamber for heating gases in which there are at least four heating elements or four groups of heating elements including an electrically conductive material, wherein each heating element or group is connected to a separately regulatable and/or controllable subsystem of an electrical energy network and can thereby be heated by direct current flow, wherein each heating element or group can be controlled or regulated with respect to at least one either identical or different value of a parameter selected from the group consisting of temperature, heating power, current, voltage and resistance, or with respect to another heating element process variable, which can be influenced by the device, and wherein at least four regulatable and/or controllable subsystems are DC-isolated from ground potential. The invention also relates to a corresponding method for the thermal treatment of corrosive gases.