| 초록 |
The behavior of uranium during thermal treatment of halogen-containing plastics is investigated using Gibbs free energy minimization method. Two-step simulation method was used considering that the decomposition and combustion of plastics occurs very fast and the reaction of surrounding gas and uranium species in the bulk ash occurs relatively slow. UO3, UO2Cl2 and UO2F2 were determined as volatile uranium species under typical incineration conditions (1000-1300K) and high-temperature melting conditions (1300-1800K). A significant fraction of gaseous uranium species can be emitted during the incineration of halogen-containing waste. The volatility increase of uranium species was greater for high-temperature melter due to the more elevated temperatures. However, for molten carbonate salt oxidizer, one of the promising alternatives to incinerator, no significant volatilization of uranium species could be expected. UO3 and UO2(OH)2 were found as volatile uranium species for molten salt oxidation but their fractions were extremely small and negligible. |
