Probing the inner structure of a blast furnace by cosmic-ray muon radiography

By using the detection system of the near-horizontal cosmic-ray radiography originally developed for probing inner structure of volcanic mountains, a measurement was conducted to probe the inner structure and its time-dependent change of the blast furnace for iron-making. Precise determination (± 5 cm) of the thickness of brick used for both base-plate and side-wall was made in 45 days; a crucial information to predict a life-time of the furnace. Also, the local density of iron-rich part was determined in ± 0.2 g/cm in 45 days; static structure as well as time-dependent behavior can be monitored for the iron-rich part of the furnace during operation.