[3F05-09] Decommissioning Technology

[3F08] Volume reduction of concrete contaminated by ¹⁴CO₂

(1) Condition for separating aggregate by rubbing

*Hitoshi Nakashima¹, Norikazu Kinoshita¹, Kazutaka Torii¹, Yuki Sasaki¹, Mamoru Hanzawa¹ (1. Shimizu corporation)

Keywords:rubbing condition, separation of aggregate, contaminated concrete, fine powder

The ¹⁴CO₂ produced during long-time operation of nuclear power plants has been adsorbed in the surrounding concretes. The amount of ¹⁴C cannot be ignored for the decommissioning. If aggregates can be isolated from concretes debris, the volume of the radioactive wastes can be reduced. The basic test was carried out to reduce the volume of the radioactive wastes contaminated by ¹⁴CO₂. Aggregates were isolated by rubbing using a Los Angeles machine from concrete debris prepared as simulated wastes. We will present trends of the amounts of production of fine powder produced by different condition of heating condition of samples carried out prior to rubbing, size and amount of iron ball loaded together with the debris.