放射性废物的稳定化.pdfVIP

CHAPTER 17 Radioactive Wastes Stabilization The nuclear age in the 20th century has left behind a legacy of radioactive waste streams that are in need of proper disposal or permanent storage. Solving this problem is a major technological and environmental challenge in the 21st century. Radioactive waste materials are stored in several countries that were active in the development and production of nuclear weapons; the United States, former Soviet Union countries, and Great Britain are prominent among these. In addition, other countries using nuclear energy for power production are accumulating their own inventories of radioactive waste. The radioactive waste comes in all forms and shapes, and has various chemical and radiological characteristics. Solids, semi-solids, and liquids are stored at various US Department of Energy (DOE) sites and at former “closed cities” in Former Soviet Union countries, where nuclear weapons were produced. The level of radioactivity in these waste streams varies; in spent nuclear fuel rods it may be very high, whereas in personnel protective outfits used in laboratory research work, only suspect amounts of contamina- tion may be present. The waste streams consist of uranium tailings, process liquids, dismantled components, incinerated residues, liquid salt wastes, and even cement debris of demolished buildings with fixed contamination. In addition, some waste streams may also contain chemical constituents that are chemically hazardous, corrosive, flammable, or volatile. These waste streams must be stabilized so they will not find their way into groundwater, air, or other pathways and affect human lives through air or the food chain. Because of the wide variation in the waste stream composit