Glass waste form

Converts secondary wastes to a high-quality glass waste form. 

The successful production of a nonleachable glass waste form from mixed low-level waste allows land disposal of the waste at a lower cost than the baseline technology (cementation) if it were used to stabilize the waste. This savings is primarily due to the large waste volume reductions realized during vitrification. In addition, glass final waste forms have been shown to have decreased teachability and increased structural stability as compared to the baseline waste form. 

Aloy, A. S., Iskhakova, O. A., Koltsova, T. I. Trofimenko, A. V. 1998. Glass waste form performance for disposal of the cesium and strontium concentrate resulting from the partitioning of HLW. Materials Research Society Symposium Proceedings, 506, 901-906. 

Chamberlain, D. B., Hanchar, J. M. et al. 1997. Development and testing of a glass waste form for the immobilization of plutonium. Materials Research Society Symposium Proceedings, 465, 1229-1236. 

Of these three processes, some have received more study than others. There have been a number of determinations of leach rates (step 1) particularly from borosilicate-glass waste forms (see, for example, 1, 3), but there has been minimal effort to deter-... 

Na, and B from a glass waste form. If, on the other hand, this test is to be adopted for a CBPC waste form, such as Ceramicrete, one may look for Mg, K, and P as the matrix components. Thus, the PCX evaluates the durability of the matrix material, which is a result of the integrity of the individual elements within the matrix. 

As may be seen from Table 17.8, Cs was added either as CsNOs or CsCl in the first three waste streams, whereas the form of Cs was not known in the last case, but certainly it was soluble because it was detected in wastewater. The TCLP results indicate that Cs, although added as nitrate or some other soluble form, is well immobilized. The LI is not as high as 18 that was reported by Bamba et al. [27] for a glass waste form, but it is certainly higher than the minimum of 6 expected from cement waste forms [28]. 

Laboratory testing at various scales, up to an engineering scale that was 1/16 the size of the planned full-scale unit, has been under way since about 2003. The objective of this testing has been to identify additives that will promote the formation of a suitable final glass waste form. It is important that the waste formed exhibit minimal leaching of radioactive components and other contaminants of concern, such as RCRA heavy metals (Buelt et al 1987 Loehr et al 1992 Thomas and Treat, 2001). 

Dacheux N, Clavier N, Le Coustumer P, Podor R (in press) Immobilization of tetravalent actinides in the TPD structrrre. Proc 10th Inti Ceramics Congress. Vincenzini P (ed) Techna Publishers, Florence, Italy Davis DD, Vance ER, McCarthy GJ (1981) Crystal chemistry and phase relations in the synthetic miner s of ceramic waste forms. II. Studies of uranirrm-containing monazites. In Scientific Basis for Nuclear Waste Management, vol. 3. Moore JG (ed) Plentrm Press, New York, p 197-200 Day DE, Wu Z, Ray CS, Hrma P (1998) Chemically durable iron phosphate glass waste forms. J Non-Crystalline Solids 241 1-12... 

Plasma arc treatment. The spent fuel is placed directly into a plasma centrifugal furnace with depleted uranium and neutron absorbers, where it is melted and converted into a HLW glass waste form. 

Glass material oxidation and dissolution system. The spent fuel is placed in a glass melt furnace where it is oxidized by lead dioxide and then converted into a LILW-LL glass waste form. 

Dissolve and vitrify. The spent fuel is dissolved and mixed with depleted uranium to reduce the enrichment. The mixture is then fed into a vitrification plant for conversion to a LILW-LL glass waste form. 

Considering the second category, it can be seen that the final product of three of the processes is a glass waste form, where the radionuclides are dissolved and immobilized. The final product of the fourth process (can-in-canister) is a metallic can (with the untreated spent fuel in it) embedded in a glass block. 

---