WECO-RTO are regenerative heat exchanger to utilize the energy of the hot clean air to the largest extent possible for heating the cold exhaust air. The energy conversion efficiency of the heat exchanger constitutes above 90% and even the energy at low concentrations of pollution in the exhaust air allows to operate the exhaust air cleaning plant in an autothermical way. Because of a combustion chamber temperature above 800°C comparatively low residual concentrations of NOX (< 50 mg/Nm3) and CO (< 50 mg/Nm3) remain in the clean air. Also the emission of CO2 is considerably reduced due to the low fuel consumption.
The exhaust air flows over a previously heated bed 1 and is heated to the combustion temperature in the oxidating chamber. In the combustion chamber the organic pollution of the exhaust air is oxidated to CO2. The hot clean air left the combustion chamber over bed 2 and bed 3 and heat these up.
The exhaust air flows over the heated bed 2 in the oxidating chamber and is heated. The clean air is utilized to warming the third heat exchanger. Simultaneosly a component current of the clean air is used to clean the previously with exhaust air loaded bed 1 of remaining contaminant.
The exhaust air enters the oxidating chamber over bed 2 and is heated to the combustion temperature. The hot clean air leaves the oxidating chamber through regenerators bed 1 and bed 3and is simultaneosly warming the material of the heat store.