Management of carbon dioxide released from spent nuclear fuel through voloxidation

The management of radioactive carbon (C-14) from spent nuclear fuel (SNF) in a voloxidation process is vital to prevent radioactive contamination of the environment. Thus, a double alkali method was applied to absorb the gaseous phase of C-14 (CO2) and to immobilize radioactive carbon into a stable structure. Based on the two-film theory, mass transfer and enhancement factor were evaluated for CO2 absorption in NaOH solution with regards to the effects of operating conditions such as the solution concentration, CO2 partial pressure, and gas flow rate on the absorbing performance. The absorption tests were carried out targeting the successful capture of CO2 released from SNF with a high decontamination factors (DF) more than 10(3). Causticization with Ca(OH)(2) leads to the immobilization of absorbed carbon into a scalenohedral calcite (CaCO3) crystal, and its stable and nonporous characteristics suggested that calcite is a suitable structure for preparing waste forms stored in a geological repository.

Automated summary

The study focuses on the management of radioactive carbon from spent nuclear fuel through a double alkali method, evaluating the effects of operating conditions on CO2 absorption performance. Causticization with Ca(OH)2 leads to the immobilization of absorbed carbon into a stable structure suitable for geological repository.