Waste gas treatment system and waste gas treatment method

Abstract

The present invention comprises: a first catalyst disposed in a piping and promoting the reaction of nitrogen oxides with ammonia; a second catalyst, which is an oxidizing catalyst disposed in the piping downstream of the exhaust gas flow direction than the first catalyst; a reducing agent supply unit that supplies a reducing agent that becomes ammonia to the aforementioned piping upstream of the first catalyst when the first catalyst arrives; a first catalyst outlet sensor that measures the nitrogen oxide concentration of the aforementioned exhaust gas downstream of the first catalyst and upstream of the second catalyst; a second catalyst outlet sensor that measures the nitrogen oxide concentration of the exhaust gas downstream of the second catalyst; and a control device that controls the amount of reducing agent supplied from the reducing agent supply unit to the piping based on the detection results of the first catalyst outlet sensor and the second catalyst outlet sensor.

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