Monitoring nitrogen oxides emissions from e.g. adsorption filters, gas scrubbers or catalysts used in waste gas purification using a solid electrolyte gas sensor

摘要

Measuring nitrogen oxides inside and outside a combustion process comprises feeding a gas mixture over a catalyst at more than 700 deg C, removing all components of the gas mixtures that disrupt the sensor signal, converting all other nitrogen oxides into NO, naturally cooling the measuring gas, heating the gas on an electrode (2), reacting with oxygen to give NO2, and measuring the potential at the electrode (1,2). An Independent claim is also included for an apparatus for carrying out the nitrogen oxides measuring process comprising two electrodes arranged on a heated ceramic solid electrolyte (3) which is connected to a heated catalyst (5) at the measuring gas inlet side.