Dielectric Properties of Low-Level Liquid Waste
Objective
DOE sites such as the Rocky Flats Environmental Technology Site and Oak Ridge National Laboratory (ORNL) are pursuing microwave heating processes for mixed and low-level radioactive wastes. Because of the lack of a dielectric material database on chemicals found in low-level liquid waste (LLLW), these microwave programs must often use trial and error methods and rely on past experience to attempt to predict the behavior of these thermal processes. Nonlinear thermal processes, such as thermal runaway, cannot be modeled without knowledge of the temperature dependence of the dielectric properties. Often this data does not exist; if it does, only very limited data near room temperature are available. This project will develop a data collection containing measurement of dielectric properties of various LLLW simulants as a function of composition and temperature that can be used to predict the behavior of a variety of microwave thermal treatment technologies, which have the potential to substantially reduce the volume of the LLLWs stored at many DOE sites.
Progress
Contact with the Remedial Action Program Center (RAPIC) continued to collect further information on the dielectric properties of LLLW.
Several LLLW simulates and recipes are being obtained.
Measurements of the dielectric properties of water and air were obtained, and the experimental system was calibrated.
After calibration, several measurements of the 4M and 6M Hanford simulates were performed. It was found that the dielectric constant (e') and the dielectric loss (e") of the simulates decrease with an increase in frequency and temperature. The dielectric data for the 4M simulate are more extensive than the data on the 6M simulate. Dielectric properties are affected by the composition of the simulate. A portion of the data for the 4M Hanford simulate is shown below:
| 4M Hanford Simulate | ||||||
|---|---|---|---|---|---|---|
| Frequency (GHz) |
22°C | 30°C | 40°C | |||
| e' | e" | e' | e" | e' | e" | |
| 0.5 | 80.22 | 907.91 | 82.18 | 1065.98 | 87.59 | 1348.6 |
| 2.5475 | 43.10 | 173.49 | 44.06 | 218.81 | 45.30 | 275.36 |
| 5.0825 | 37.50 | 104.59 | 38.67 | 120.98 | 40.24 | 150.43 |
| 10.055 | 28.59 | 60.58 | 30.55 | 67.76 | 32.65 | 81.53 |
| 15.0275 | 21.48 | 42.71 | 22.83 | 48.59 | 23.33 | 57.04 |
| 20 | 21.76 | 36.51 | 23.70 | 40.77 | 25.78 | 46.59 |
The following individuals are being contacted to acquire additional recipes for simulates to be used in the present investigations: Greg Springer and Bill Roushey, Rocky Flats; Terry White, Oak Ridge National Laboratory; Glenn Bastiaans, Ames Laboratory; Bob Peterson, EET Corp.; and Isaac Suazo, Los Alamos National Laboratory.
The recipe for the Rocky Flats sludge was obtained. It is
PI: M. A. Ebadian, Florida International University, (305) 348-2446