Monthly Research Progress
Institute for Clean Energy Technology
Support of Oak Ridge Site Closure
Characterization of Corrosion for Closure of Oak Ridge Research Reactor
The fabrication of a new submergible instrument box is nearly complete. Pool simulated-target measurements and leak test for submergible instrument box will be implemented in early August. In order to correct images due to the difference in the indices of refraction of the air within the box and the water surrounding the aluminum pit corrosion, our uncertainty analysis expert has begun a fresh examination of the problem. The second deployment into the Oak Ridge Research Reactor pool is scheduled for the week of September 11.
Bio-availability and Speciation of Mercury in the Oak Ridge Ecosystem
In July, we presented "The Bioavailability and Phytoremediation of Mercury Contaminated Soils from Oak Ridge" at the 18th World Soil Congress in Philadelphia, PA. The presentation was well received by the international audience. In addition, the soil samples were prepared for the new experiment on bioavailability of HgS-contaminated Oak Ridge soils. In August we will summarize the study on extraction of HgS from contaminated soils and will write a journal manuscript.
Accelerating Phytoremediation by Monitoring Plant Status
During the month of July, we built and tested a prototype sunlit chamber; these sunlit chambers will be used to investigate different channels of mercury uptake, such as plant root uptake of soil mercury and leaf intake of atmosphere Hg. Based on the test results, some improvements have been made and we have purchase necessary material to build six chambers for future experiments. We have also seeded a batch of Indian mustard plants for experiments that will be conducted in the following month. In the coming month, we are planning to conduct more phytoremediation experiments.
Support of Hanford Single Shell Tank Waste Disposition
In-tank/At-tank Characterization for Closure of Hanford Tanks
Stereovision. Experiments were performed using the Hanford waste tank simulation setup that the FTP effort has been using to characterize the performance of the FTP system. We tried different stereo matching approaches in order to obtain better results. We also tried applying the "grid" projection used by FTP in order to overcome the textureless problem associated with monochrome backgrounds and targets; preliminary results indicate that the use of a grid pattern improves the stereovision results.
Laser-induced fluorescence-spectral imaging. During July, we purchased optics that will enable us to investigate the fluorescence of simple uranium compounds when excited with the 266-nm fourth harmonic of a Nd:YAG laser. The LIF experiments using 266-nm excitation will be performed during early August.
Microwave-induced plasma-cavity ringdown spectroscopy. Mercury (Hg) vapor from three types of mercury-spiked water and soil have been measured using cavity ringdown spectroscopy. No additional sampling procedures, such as pre-concentration, heating, or other chemistry efforts, were used. The real-time information shows that the ringdown technique may be a simple and effective tool to study mercury dynamics, such as transform and fate of mercury in contaminated sources on DOE sites.
Fiber optic sensors. We continued our work on optimizing the procedure for making scintillating optical fibers. Several scintillating optical fibers consisting of scintillating agents (NaI, CsI, CdSe/ZnS core/shell quantum dot) were prepared and tested. Sensitivity improvement for gamma ray detection has been observed in some of the fibers. In general, higher sensitivity is achieved with the fibers having lower scintillating agent concentrations inside the fiber. This means that we need to reduce the concentration of the scintillating agent inside the fiber in our continuing work.
Fourier transform profilometry. During July, we expanded our efforts to prepare a report describing the results from the first stage of simulation testing by investigating the operator dependence of the current FTP method. This is being done by having several members of the ICET FTP team to independently obtain volume determinations from the same set of FTP images. A statistical analysis will be performed using the results obtained and will be included in the report on the first stage of evaluation of FTP performance. In order to test the ability of critical FTP optical components (Ronchi filter, diffuser, camera) to withstand nuclear radiation, we have developed a protocol for radiation testing. The planned procedure is to record every five minutes an image that includes the Ronchi filter, the diffuser, and a portion of a thin stainless steel plate that simulates the FTP probe wall. The protocol has been slightly modified in response from suggestions from our Hanford collaborators. In preparation for radiation testing, the camera control and image acquisition system has been modified and has been tested in a long-duration (>16 day) operation. In order to facilitate remote system monitoring during radiation testing, wireless network hard drive access (for saving the images from the computer at Cs-137 irradiator site) has been established. The system is currently undergoing wireless network access reliability test with a mock-up of Cs-137 irradiator chamber. We have begun development of imaging analysis software that will allow us to automatically analyze multiple regions-of-interest (ROIs) within a given image; this software will be used to quantitatively characterize the results of the radiation testing of the FTP components.
Process Chemistry and Operations Planning for Hanford Waste Alternatives
The upgraded version of the DBLSLTDB database was released to engineers at Hanford and at Savannah River. This activity was necessitated by OLI Systems Inc., initial release of ESP version 6.7 followed, in short order, by the release of version 7.0. The fitting of the data and the subsequent evaluation of the various constituents covered by the thermodynamic conditions within the database has taken considerable effort. Moreover, this activity is necessary with any potential future changes to the OLI Public database that may impact the chemistry of DBLSLTDB. For these reasons discussions with OLI personnel have been initiated with the express purpose of investigation the integration of DBLSLTDB in the standard Public database. This activity would primarily allow for certification.
Solubility studies on the Na-F-PO4-OH system continued. These new experiments are being conducted at 20°C and are based on a request from Hanford engineers. All of the samples in water, 1- and 3-m NaOH have equilibrated and sample work up has been completed for the 3-m series and for most of the 1-m samples. Following receipt of the laboratory data the results will be compared to predictions using V7DBLSLTDB, and then, if necessary, the determination of solubilities at 15°C.
Disposition of Idaho HLW Calcine
Support of CH2M-WG Calcine Disposition Project
The orders have been placed for the feeding systems and mixer for the pilot scale system. The lead times for both are 10 - 12 weeks. We expect to begin shakedown testing of the mock up in October/November 2006. No further lab work is expected to be done between now and the mock up work. All notebook pages have been scanned into the system.
Support of SRS Salt Disposition and Other SRS Alternatives
Modeling and Experimental Support for High-level SRS Waste Disposition
The DASR experiment with the tank 38 salt cake simulant with 1.5% by weight of sludge added has been completed. Fractions are being worked up for analysis. As expected the duration of the experiment was between the salt cake and the salt cake with 3% added sludge. ESP calculations are in progress to compare to the experimental results. Solubility experiments for the CsNO3-KNO3-Water system are continuing.
Process Improvements for the Defense Waste Processing Facility (DWPF)
On-line slurry analysis. All the work related with dual-pulse (DP)-LIBS will be postponed to next year because we are unable to purchase a dual-pulse laser system in this fiscal year. Work on collecting calibration data for simulated melter feed continues. Methods to improve the mixing process of frit with the DWPF base sludge were studied. Various data analysis methods were tested on glass batch and slurry data to obtain the best method for each sample type. Beside the slurry measurement, we have also planned to evaluate some powder samples with LIBS based on the discussion in monthly teleconference with SRNL. LIBS had been successfully used to evaluate the glass batch by first pressing the powder into the pellet in our early work. In this work, we will evaluate the powder sample with LIBS for three different sample forms (i.e. powder, powder pressed into pellet form with and without binder). The powder composition was obtained from SRNL. The chemicals which were not available in our laboratory were ordered. The power batch were prepared based on the receipt provide by SRNL. Five power samples of different compositions of Cerium will be made from the batch for LIBS calibration.
Improvement of waste throughput. Experiments run so far to examine the relative reaction rates of the two frits have not provided the information expected. These tests have been done both with a dried version of the Case 7d SRAT as well as with the slurry. It appears that in both sets of experiments, the 200 frit reacts more rapidly (at lower temperatures) than the 320 frit, and that's not what has been observed in practice. The products of these experiments are now being evaluated by Differential Scanning Calorimetry and optical microscopy. Future batches, in particular Sludge Batch 4 (SB4), to be run at DWPF expect to contain much more alumina. We will be receiving SB4 simulant and a new frit, Frit 503, to study these reaction rates. Frit 418, which we already have a supply of, will also be tested.
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
During July, the results of our first series of media velocity testing were presented at the 29th Air Cleaning Conference held in Cincinnati, OH. A shipment of 17 HEPA filters was received from Camfil Farr and preparations were made to begin a new series of media velocity tests. Writing of manuscripts to be submitted to Review of Scientific Instruments describing the ICET aerosol generator and HEPA Filter Test Stand was continued. ICET engineers within the HEPA group made additional progress in designing a filter holder to facilitate testing and air blow back cleaning of large CeraMem filtration units.
Inquiries may be addressed to:Dr. Roger King, Interim Director
205 Research Blvd.
Starkville, MS 39762-5932