Aerosol and melt chemistry in the ACE molten core-concrete interaction experiments

Experimental results are discussed from the internationally sponsored Advanced Containment Experiments (ACE) Program on the melt behavior and aerosols released during the interaction of molten reactor core material with concrete. A broad range of parameters were addressed in the experimental program: Seven large-scale tests were performed using four types of concrete (siliceous, limestone/sand, serpentine, and limestone) and a range of metal oxidations for both boiling water and pressurized waster reactor core debris. The release aerosols contained mainly constitutents of the concrete. In the tests with metal and limestone/sand siliceous concrete, silicon compounds comprised 50% or more of the aerosol mass. Releases of uranium and low-volatility fission-product elements were small in all tests. Releases of tellurium and neutron absorber materials (silver, indium, and boron from boron carbide) were high.