Abstract: An arrangement for the catalytic oxidation of the harmful components in a cooled carrier gas from a technical process. The arrangement includes two parallel gas ducts which are connected at one end through a bend and whose other ends are connected to gas lines for the carrier gas and for purified gas. The gas ducts are connected to each other through a three-stage thermal energy return unit. The exchanger stage of the thermal energy return units are arranged spaced from each other and are composed of individual heat tubes whose number increases from exchanger stage to exchanger stage. The size ratio of the heat-exchanging surfaces of heating part to cooling part of each exchanger stage decreases in flow direction of the carrier gas from exchanger stage to exchanger stage. The catalyst is integrated in the gas duct for the carrier gas immediately downstream of the heating part of the last exchanger stage.