UREA QUALITY DIAGNOSIS SYSTEM

摘要

A urea quality diagnosis system capable of accurately diagnosing the quality of aqueous urea solution within a urea tank. The concentration and the level (L) of an aqueous urea solution within a urea tank (16) are detected, and when the level (L) is higher than or equal to a predetermined value, the quality of the aqueous urea solution is diagnosed on the basis of the detected value of the concentration of the aqueous urea solution.