Patent ID: 8156787

Claim:
A device for detection of the concentration of sulfur in fuel or oil, comprising: a metal or metal compound able to trap a sulfur component in exhaust gas arranged in a flow path of exhaust gas produced by combustion of fuel or oil, where a property of the metal or metal compound changing along with an increase in an amount of sulfur component trapped by the metal or metal compound is measured; and a controller configured to detect the amount of sulfur component trapped in the metal or metal compound from a measured property, to detect an actual cumulative value of an amount of SO X actually contained in the exhaust gas from a detected amount of sulfur component, to calculate an assumed cumulative value of an amount of SO X , assumed to be included in the exhaust gas based on an operating state of the engine under the assumption that fuel or oil of a sulfur concentration assumed in advance is used, and to determine that fuel or oil of a sulfur concentration higher than the concentration of sulfur assumed in advance is being used when the actual cumulative value of the amount of SO X becomes larger than the assumed cumulative value of the amount of SO X by a predetermined value or more, wherein the actual cumulative value of the amount of SO X and the assumed cumulative value of the amount of SO X are cumulative values in a predetermined time period, and the predetermined time period starts advancing when the fuel is refilled or the oil is changed.