Patent ID: 7189373

Claim:
A carbon monoxide removal system comprising: plural preferential oxidation reactors disposed in series which remove carbon monoxide contained in reformate gas via a catalyst, the preferential oxidation reactors comprising a first preferential oxidation reactor and a second preferential oxidation reactor arranged further downstream than the first preferential oxidation reactor; an air supply mechanism which supplies air containing oxygen as an oxidizing agent to the first preferential oxidation reactor and the second preferential oxidation reactor; a first temperature sensor which detects a temperature of the first preferential oxidation reactor; a second temperature sensor which detects a temperature of the second preferential oxidation reactor; and a controller functioning to: determine a target carbon monoxide conversion rate of the first preferential oxidation reactor based on the temperature of the first preferential oxidation reactor; determine a target carbon monoxide conversion rate of the second preferential oxidation reactor based on the temperature of the second preferential oxidation reactor; control the air supply mechanism so that an air supply flow rate to the first preferential oxidation reactor based on the target carbon monoxide conversion rate of the first preferential oxidation reactor, and an air supply flow rate to the second preferential oxidation reactor based on the target carbon monoxide conversion rate of the second preferential oxidation reactor.