March 2004
DIAL's Research Highlights
Diagnostic Instrumentation & Analysis Laboratory
Mississippi State University
John Plodinec, Principal Investigator
Prepared for the U.S. Department of Energy
Office of Science and Technology
Cooperative Agreement DE-FC01-04EW54600
Task 1
Support of Closure Sites
Fernald Silos Project Monitoring and Control Integration
Waste stabilization formulation development. A formal test plan was developed for the waste stabilization formulation development efforts. The test plan outlines the activities that need to be completed prior to initiating the formulation work, the various tests that will be performed, and the formulations that will be tested during this study. Due to the nature of the study, it is expected that the stabilization test plan will be revised as necessary to accommodate the direction of the formulation development.
K-65 has a high radium content, therefore, formulation development work for the Fernald Silos material must be performed in a facility that has the capability to control radon emissions from the waste material. A multiple glove box unit was designed and fabricated by DIAL personnel. Three interconnected units were fabricated; one unit will be used for material transfer, one unit for vibration testing of the treated material, and one unit for sample preparation.
Larbi Bounini, the Fernald leader for the formulation development, visited the DIAL facility to observe surrogate testing and to evaluate the progress of work. Twenty treatment samples were prepared in the DIAL laboratory using a K-65 surrogate. These samples were prepared in order to determine how different waste and treatment components affected the final waste form properties. The waste includes K-65 (surrogate for the initial testing), bentonite clay, water, and a flocculating polymer additive (this polymer will be added to the waste stream in the full-scale remediation facility during the retrieval activities). Various treatment components included cement, fly ash, and a super plasticizing agent to improve the flow properties of the treated material.
The surrogate testing provided an indication of how the waste form behavior trends change as various waste and treatment compositions are changed. The information gained during the surrogate testing has proven to be valuable, however the K-65 surrogate is a physical surrogate. The actual K-65 material is not chemically similar to the surrogate, so formulation development with K-65 is integral to providing useful treatment formulas to the Fernald Closure Project.
Wastewater equilibration study. A formal test plan was developed for the wastewater equilibration study. The test plan outlines the activities that need to be completed prior to initiating the wastewater treatment work, the various sample analyses that will be performed, and the water treatment options that will be tested during this study. Due to the nature of the study, it is expected that the stabilization test plan will be revised as necessary to accommodate the direction of the various treatment options examined.
The following activities are planned for the upcoming quarter:
- Begin formulation testing with K-65,
- Begin the wastewater equilibration study,
- Participate in the full-scale surrogate testing of the silos waste retrieval system (SWRS),
- Perform real-time data analysis for the full-scale surrogate testing of the SWRS.
Accelerating Phytoremediation by Monitoring Plant Status
During this month, we have been analyzing samples and data from previous phytoremediation experiments. We presented some of our results on mercury phytoremediation and related process monitoring during a recent meeting with the DOE Oak Ridge Operation officer and representatives from Bechtel Jacobs Company at Oak Ridge. We are planning to start new phytoremediation experiments in the coming months. Meanwhile, we will continue to analyze samples and data from previous experiments.
Task 2
Support of Hanford Single Shell Tank Waste Disposition
In-tank/At-tank Characterization for Closure of Hanford Tanks
Stereovision. During March, DIAL's stereovision effort continued its work on a scientific journal paper describing our state-of-the-art system.
Microwave-induced plasma-cavity ringdown spectroscopy. When the YAG laser system had been fixed, the ringdown measurements resumed. Spectral background interference was extensively studied in the UV spectral region in the vicinity of the mercury transition at 253 nm. Using the MIP-CRDS system, a high-resolution ringdown spectrum of the forbidden transitions in Hertzberg band I 
of O2 was obtained. Ringdown measurements of this band of O2 under low-pressure conditions have been previously reported in the literature. However, no one has yet reported the ringdown spectrum of this band under atmospheric conditions (both the plasma on and off). This spectrum is not only useful for the plasma-CRDS spectral interference study, but also very valuable for kinetic modeling of high-temperature combustion. Spectral assignment and data analysis are on-going. Additional effort was also focused on optimization of the MIP-CRDS system for mercury measurements.
Fiber optic sensors. Work this month focused on optimization of the conditions for making ZnS-doped sol-gel fiber. The effects of sol-gel silica precursor, the reagent used to form ZnS, and the concentration of ZnS in the sol-gel silica have been studied.
Fourier transform profilometry. The DIAL Fourier transform profilometry (FTP) effort identified and obtained light sources and reflectors for the probe utility light and the fringe projector; fabrication of associated components is underway. The blueprints of the Hanford S Farm tanks are being converted into AutoCad format; this will enable us to fabricate full-size mock-ups of the risers for in-housing testing. In order to fully utilize the functions that available in the current camera system, work continued on improvement of camera-control and image-acquisition software. Due to the large size of the Hanford tanks, the distortion caused by non-perpendicular target surfaces in the FTP measurement has been identified; work on possible methods of correction continued. Efforts continued on the engineering design work for the insertion probes; materials will be ordered as soon as the designs are complete and proper sizes of tubing are located. Our efforts on image quality improvement continued.
Information sifting. The information sifting effort has completed the identification feature in the spectral identification tool. Users are now able to determine the closest match from the library based on Euclidean distance between the unknown spectrum and those in the library.
Flexible Scintillating Optical Fiber Sensor for Determination of Liquid Level
Sol-gel preparation procedures were modified and tested during this reporting period. The chemical combinations included two gelation catalysts, two silicon alkoxide precursors, and several scintillation compounds as the doping material. Some of the mixtures resulted in opaque and fragile glasses not suitable for development of the optical fiber sensor. The sol-gel glasses of good optical quality were coated on the inner wall of light guiding fused silica capillary for further testing. Assembly of the photomultiplier detection system is scheduled for the next reporting period.
Tank Leak Detection and Monitoring System
The special ringdown gas cell was assembled on the portable optical plate. A tremendous effort was focused on the initial ringdown alignment. Due to the special design of the gas cell (no adjustable parts in the mirror mounts), ringdown alignments of this gas cell are very challenging. However, a preliminary alignment was successfully achieved. The light source used was provided by a temperature controlled diode laser with the near-IR output of ~ 1650 nm, where two transition lines of water are to be used for determination of moisture concentrations. This compact laser source was also mounted on the same optical plate and the laser output was injected into the ringdown gas cell through a section of single mode optical fiber. The ringdown signal was detected by a photodetector and monitored by an oscilloscope. Although a clear mode buildup pattern has been achieved, the system alignment needs further improvement before moisture concentrations can be accurately measured. A laptop computer ordered for the data processing of the tank leak detection system (TLDS) has been delivered and the ringdown software and the data acquisition system will be developed and loaded to the computer.
A technical hurdle needs to be overcome. A strong optical feedback was observed in this initial ringdown alignment due to the use of the non-wedged ringdown mirrors. In order to mitigate/eliminate the optical feedback effect, which influences the measurement accuracy, a pair of wedged ringdown mirrors will be employed in the final prototype TLDS.
Task 3
Disposition of Idaho HLW Calcine
Support of INEEL Calcine Disposition Project
Dr. W. Gene Ramsey will be leaving DIAL. Drs. Adriana Giordana and Mark Bricka will lead the project. Dr. Giordana will be the point of contact. Dr. Tom Thomas has been informed of the change and provided with new contact information.
The problems in dissolving calcium fluoride have been solved and a new analysis method has been developed. The new compositional analysis results for the calcine simulants appear consistent with previous analysis results obtained by ICP-SP3. DIAL is reviewing the literature survey provided by Dr. Thomas.
Task 4
Support of SRS Salt Disposition and Other SRS Alternatives
On-line Analysis for Defense Waste Processing Facility
Dr. Singh and Dr. Plodinec visited SRTC on March 23 to discuss various issues about the LIBS project. The SRTC has expressed a need to analyze the sludge sample in addition to on-going study on pellet and glass samples. The SRTC will provide some sludge samples for initial tests. The process of making glass samples for LIBS calibration has been delayed because Dr. Ramsey is leaving and because of the need for ordering some chemicals. The pellets with different CaCO3 were made and used to obtain the calibration data for Ca in pellet form. A new glass batch mixture based on EA glass composition was made. The new batch will be used to prepare the various pellets for the calibration of Fe, Al, Mg, B, Na, Li, and Si. Different data analysis techniques (e.g., self-absorption correction, plasma emission normalization, etc.) are under evaluated to improve LIBS accuracy and precision.
Task 5
HEPA Filter Performance Assurance
Regenerable HEPA Filter Performance Testing
During the week of February 29 - March 4, three papers were presented at the 2004 Waste Management Conference in Tucson, AZ:
- "Measurement Uncertainty in Determination of Particulate Loading by EPA RM-5 and RM-5I,"
- "A Comparison of Methods for Particulate Measurement and Monitoring of HEPA Filters,"
- "Evaluation of Mass Emission Rates Down Stream of HEPA Filters as a Function of Source Terms and Selected Failure Modes."
During the month of March, the new pump for supplying the liquid to the atomizing nozzle arrived. This pump is a magnetic drive gear pump. It has a higher capacity and produces a more constant liquid flow rate than the syringe pump. There has been ongoing work in the HEPA laboratory to get ready for preliminary DOP testing. Also received during March was a new aerodynamic particle sizer (APS) manufactured by TSI, Inc. of St. Paul, MN. Preliminary work on calibration of this instrument was begun.