Monthly Research Progress
Institute for Clean Energy Technology
Support of Oak Ridge Site Closure
Characterization of Corrosion for Closure of Oak Ridge Research Reactor
Because of lack of funds for the end of the federal fiscal year, our Oak Ridge collaborators were unable to provide the support required to enable deployment into the Oak Ridge Research Reactor (ORRR) pool during September; a revised deployment date is being sought.
Bio-availability and Speciation of Mercury in the Oak Ridge Ecosystem
In November, we systematically tested the new mercury analyzer. Instrument parameters such as detection limit, detection quantity, precision and accuracy, memory effects, as well as calibration procedures have been studied. A series of contaminated soils and plant samples were compared with both cold vapor atomic absorption spectrometer and the mercury analyzer. The results will be summarized, and a manuscript is in preparation. We also submitted a manuscript entitled "Stability and Bioavailability of Mercury Sulfide in Oak Ridge Soils" to WM 07.
In December, we will continue work on the two manuscripts.
Accelerating Phytoremediation by Monitoring Plant Status
During this month, we finished the mercury phytoremediation experiments with Chinese brake fern; this experiment was started in August with aged Oak Ridge soil. Also during this month, we finished the experiments on investigating the different mercury uptake mechanisms, such as plant root uptake of soil mercury and leaf intake of atmospheric Hg, using the special chambers designed and constructed by ICET engineers and technicians. Currently, we are running a new round of mercury phytoremediation experiments with fresh soil (from Mississippi). We will finish this current experiment in December.
Support of Hanford Single Shell Tank Waste Disposition
In-tank/At-tank Characterization for Closure of Hanford Tanks
Stereovision. During November, we performed a series of experiments, including some in conjunction with Fourier transform profilometry's experiments simulating Hanford waste tanks. Some images were acquired at a distance of 60 feet. Analysis of the acquired images is still in process with an emphasis on improving the disparity match. We continued our efforts to optimize the experimental setup and software for deployment into the Hanford waste tanks.
Laser-induced fluorescence-spectral imaging. We completed optimizing the 266-nm (fourth harmonic) output from our Nd:YAG laser this month. LIF experiments using 266-nm excitation and simple uranium compounds will begin. Experiments using a mercury lamp (254 nm) as the excitation source will also begin.
Microwave-induced plasma-cavity ringdown spectroscopy. During December, the microwave-induced plasma-cavity ringdown spectroscopy (MIP-CRDS) effort resumed measurements of uranium using a diode laser. Analysis and processing of the Hg ringdown measurement data continued. Measurement of multiple tank volatile organic compounds (VOCs) will be furthered when the optical parametric oscillator (OPO) laser source is delivered and available for use.
Fiber optic sensors. During this month, we designed two experiments in order to record the scintillating light spectrum with our optical fiber compatible spectrometer. In the first experiment, the scintillating light signal from a quantum dot solution in a quartz cell was focused with a lens into an optical fiber, and detected with an optical fiber-compatible spectrometer. It is expected that the scintillating light intensity fed into the spectrometer will be much higher than that in our previous experiment using fiber scintillators. A new system for this experimental design was assembled, and a test was carried out this month. However, the scintillating light signal was not high enough for the spectrometer to detect the spectrum. In a second experiment, Teflon AF tubing with a diameter of 650 mm and filled with a quantum dot solution was used as a scintillating optical fiber. Preliminary test results obtained with this scintillating optical fiber indicate that the scintillating light output is not high enough for the optical fiber compatible spectrometer to record the emission spectrum from the quantum dot solution.
Fourier transform profilometry. During November, we finished generating synthetic FTP images. The synthetic FTP images will be utilized for the FTP analysis uncertainty study and for data validation and verification. Development of the tank imaging stitching scheme has nearly been completed; the system is undergoing tests for code verification using synthetic images. Fabrication of a curved tank bottom continued. The curved tank bottom simulator will enable us to evaluate the performance of the FTP system under conditions simulating those that will pertain within the Hanford waste tanks. Our efforts to prepare a report describing the results from the first stage of simulation testing continued; a draft of the report will be provided to Hanford in December. We have been utilizing MSU's Cs-137 gamma irradiator in order to test the ability of critical FTP optical components (Ronchi filter, diffuser, SONY 78B camera) to withstand gamma radiation and to characterize the performance of the camera when exposed to gamma radiation. A set of eight pocket dosimeters has been used to characterize the change of gamma radiation intensity with distance along the radiation path centerline of the MSU gamma irradiator chamber. Our Hanford collaborators have provided us with video of retrieval efforts in tank S-112; this will enable us to better understand the conditions the FTP system will be deployed in.
Process Chemistry and Operations Planning for Hanford Waste Alternatives
The solubility experiments on the Na-F-PO4-OH system in 0, 1, and 3-m NaOH and at 15 and 25°C have been completed. The data has been worked up and is being checked for consistency against previous experiments at 25°C. Studies on the Al(OH)3 to AlOOH transition continued. A mass of gibbsite was placed in the muffle furnace at 210°C and converted to AlOOH in a period of 20 hours. TGA analysis did not reveal any residual water. Literature articles were gathered and are being used with the ESP software to see if the lower temperature transition of Al(OH)3 to AlOOH is captured in the thermodynamic software.
Work on the neural network continued with a conference call with the principal customers at CH2 M Hill Hanford Group. This call served as a point of focus for future efforts associated with network development.
Disposition of Idaho HLW Calcine
Support of CH2M-WG Calcine Disposition Project
The feeders, mixers, and control equipment are now being installed on the test stand for the mock up system. We expect to begin shakedown testing of the mock up over the next month.
Samples were taken from one drum of the calcine simulant (non-hazardous) received in September. Chemical analysis will be done on the material in order to compare it with previously used materials and to confirm the submitted analysis. We have also made two sets of cubes (17% and 34%) to test for mechanical strength. No anomalies were observed during mixing. Results will be available next month.
Support of SRS Salt Disposition and Other SRS Alternatives
Modeling and Experimental Support for High-level SRS Waste Disposition
Solutions have been prepared for the system CsNO3-NaNO3-Water in 1 and 3-m NaOH at 25°C. Several solutions have already reached equilibrium and formed solids. Calculations for the system, KNO3-NaNO3-Water in 1 and 3-m NaOH at 25°C were repeated due to the recent release of an upgrade for ESP V7.0 and preparation of these solutions has begun.
Investigations of the ESP model database(s) for uranium, neptunium and plutonium complexes are underway. The latest date associated with any thermodynamic data contained within the Public database is 1994. Consequently, an effort considerably larger than first envisioned will be needed to address the lack of data. In keeping with future development efforts regarding the Mixed Solvent Electrolyte (MSE) model it is intended to use this platform for future database development.
Process Improvements for the Defense Waste Processing Facility (DWPF)
On-line slurry analysis. Work continued on improving the performance of LIBS slurry measurement. The weak signal from Si lines found in the data of simulated melter feed indicated that the frits were not uniformly mixed and dissolved in sludge. The procedures for making the simulated melter feed will be carefully examined to find a better method to prepare the simulated melter feed.
The preliminary study on the analysis of Pu residue generated during the processing of the weapons grade Pu has shown that the sample in pellet (with PVA binder) gave the best analytical figure of merit. Due to the practical consideration, the SRNL prefers to perform LIBS analysis on pellet with no binder added and kept in the original container during the measurement. More data on this sampling method will be studied.
Two papers entitled "Analysis of Surrogate of Plutonium (Pu) Residue Using Laser Induced Breakdown Spectroscopy" and "The Parametric Study of Slurry Sample with Laser Induced Breakdown Spectroscopy" were presented at the Southeast Regional American Chemical Society Meeting, November 1 - 4, 2006, held in Augusta, GA.
Improvement of waste throughput. X-ray diffraction (XRD) experiments on SB4 simulant with Frits 418 and 503 were begun this month. Materials heated to 600°C, 700°C and 800°C are being examined. The results will be available in December.
Discussions have been started on a task involving using ICET diagnostic instrumentation to assist with melting studies using the Cold Cap Evaluation Furnace (CEF) which has been built at SRNL. This task will be a large part of our effort in the coming year.
Support of the Fernald Silos Project
Fernald Silos Project - Remediation Process Support
Final decontamination and disposition of the Fernald building and the associated systems is ongoing. Communication with the Fernald Management Team will continue through project completion.
HEPA Filter Performance Assurance
Regenerable HEPA Filter Performance Testing
Media velocity testing on Flanders Nuclear Grade HEPA filters was continued. This testing was performed with the cyclone in place. Three papers are being finalized for submission to referred journals. These papers are:
Inquiries may be addressed to:Dr. Roger King, Interim Director
205 Research Blvd.
Starkville, MS 39762-5932