May 2005
 
 

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-FC01-05EW07029

 

Task 1

Support of Closure Sites


Fernald Silos Project Monitoring and Control Integration

Waste stabilization formulation development. Formulation testing continued. During May, the primary goal was to begin the formulation testing using ADVACAST 530, a viscosity modifier. It is expected that during the processing phase, the non-homogeneity of the K-65 material will create significant difficulties in handling both the waste slurry and the grout product. ADVACAST 530 is a super plasticizer intended to reduce the viscosity of the final grout mixture without increasing the amount of bleed water present. However, preliminary testing has proven that the use of ADVACAST 530 does in fact increase the amount of bleed water for a given formulation. The testing also demonstrated that the amount of ADVACAST 530 required to create a self-pouring, self-leveling mix was three to five times the doping level indicated by the manufacturer.

The following activities are planned for the upcoming months:

  • continue formulation testing with K-65;
  • continue TCLP evaluations;
  • continue development of formulations for samples with Advacast;
  • make recommendations on the use of ADVACST 530; and
  • finalize Jacobs Engineering computer model and perform water balance simulations.

Accelerating Phytoremediation by Monitoring Plant Status

During the month of May, we started a new experiment on mercury phytoremediation. Soils from previous experiments were re-mixed and re-sampled before using again for the current experiment. Also during this month, we prepared soils for phytoremediation experiments involving CCA (chromated copper arsenate, a wood preservative agent) and copper. A preliminary experiment using the prepared soils will be conducted in the coming month. Meanwhile, we have been analyzing samples and data from previous experiments.

Bio-availability and Speciation of Mercury in the Oak Ridge Ecosystem

During this month, we ordered two manufacturer-made 8 x 4 x 4-ft acrylic aquarium tanks. We submitted a full manuscript to the Tenth International Conference on Environmental Remediation and Radioactive Waste Management to be held in Glasgow, Scotland, September 4 - 8, 2005. The manuscript title is "Bio-availability and Speciation of Mercury in Soils from Oak Ridge, Tennessee, USA." In addition, we have also started to write three mercury manuscripts from the previous experiments. Their tentative titles are:

  • Fractionation, Transformation and Bio-availability of Hg in Soils of Oak Ridge, TN;
  • Mercury Solubility, Speciation and Plant Effects (Bio-availability) in Soil of Oak Ridge, TN; and
  • Natural Attenuation Process of Hg Contaminated Soils from Oak Ridge, TN.

At the same time, we are continuing to study the changes of bio-availability of mercury species in contaminated soils with planting. The experiments have been deployed together with the phytoremediation study. Finally, this month, we have identified two students: one undergraduate student with chemistry major at MSU and one Ph.D. candidate.

We plan to have the drafts of the three mercury manuscripts in the coming month. We will conduct the preliminary experiments on a small size test bed with new functioned metal/soil blender/mixer.

Task 2

Support of Hanford Single Shell Tank Waste Disposition


In-tank/At-tank Characterization for Closure of Hanford Tanks

During May, our collaborators at Hanford have been contacted to arrange a conference call to report our progress and to discuss our efforts for them for the next Cooperative Agreement Year.

Stereovision. During this month, the stereovision effort investigated the effect of background texture/features on the precision of stereovision determinations. It has been found that when the background is textured and/or has features, the stereovision determination precision is better than when the background is uniform or texture less.

Laser-induced fluorescence-spectral imaging. During May, we attempted to record the laser-induced fluorescence (LIF) spectra of a series of simple uranium and thorium compounds using 355-nm excitation or 532-nm excitation. LIF emission was observed for uranyl acetate (for both 355 and 532-nm excitation), uranyl oxalate (for 355-nm, but not for 532-nm excitation), and uranyl nitrate (for both excitation wavelengths). No LIF emission for either excitation wavelength was observed for uranyl formate, uranyl oxide (U3O8), thorium dioxide, or thorium nitrate. Using 532-nm excitation, the relationship between LIF emission intensity and laser excitation power was investigated.

Microwave-induced plasma-cavity ringdown spectroscopy. Due to the extensive use of the plasma-cavity ringdown system, maintenance servicing of the plasma source occurred and the CCD detector of the spectrometer was sent back for vacuum cleaning. A manuscript entitled "Atmospheric Measurements of Elemental Mercury in Contaminated Soil and Water Using Cavity Ringdown Spectroscopy" was written for publication in a refereed journal.

Fiber optic sensors. In order to block stray light from entering the highly sensitive photomultiplier tube (PMT), the fibers (both scintillating fiber and shielding fiber) and the connectors have to be shielded with a black tube. During this month, we purchased a flexible black rubber tube for shielding purposes. The fibers and connectors will be inserted into this tube in assembling the scintillation fiber optic sensor.

Fourier transform profilometry. During May, the FTP effort finished and successfully tested a prototype software program for remote control of the motors that will be used for probe and elbow manipulation. An EXCEL worksheet for calculating various position parameters used for probe and elbow control under practical measurement environments was completed; this will facilitate deployment in waste tanks with differing geometries. A draft plan for FTP measurement within TVA's Regenesys tanks in Columbus, MS, has been completed and is under review; we plan to test our probe-based systems at Regenesys prior to demonstration at Hanford's Cold Test Facility. Our efforts to contact TVA to learn about conditions and schedule for testing at the Regenesys facility continued. Our efforts to reduce the weight of the elbow section housing the FTP optics continued. Investigation and prototyping of dual usage of a single light for both fringe pattern projection and utility illumination is underway. Development of a base plate to interface the support tower with the telescoping probe is on-going. In order to facilitate installation of new instrumentation at DIAL, the FTP laboratory is being moved to a different laboratory room.

Process Chemistry and Operations Planning for Hanford Waste Alternatives

Significant progress is being made on the neural network application for the G2 model. The Neur-onLine software application was received from CH2M Hill and is being evaluated with the results from the model simulations performed last month. Training of the network is currently in progress. A number of different network configuration options including predictive and backward propagation models appear to provide the lowest RMS errors.

New solutions for aluminum-nitrate solubility measurements were prepared starting with reduction of aluminum wire in caustic followed by the addition of sodium nitrate. The new procedure, as compared to using technical grade sodium aluminate, will allow for a considerably larger range of hydroxide loadings. Tentatively, it is planned to extend the solubility experiments to 7 m. Solutions were prepared in 1-m NaOH and these are undergoing equilibration.

A manuscript entitled "Solubility in the Na-F-SO4-OH System" was accepted for publication in the Journal of Chemical and Engineering Data. Three other companion papers are being prepared and it is expected that these manuscripts will be submitted in July.

Flexible Scintillating Optical Fiber Sensor for Determination of Liquid Level

Progress on this task will be reported at a later date.

 

Task 3

Disposition of Idaho HLW Calcine


Support of INEEL Calcine Disposition Project

Progress on this task will be reported at a later date.

 

Task 4

Support of SRS Salt Disposition and Other SRS Alternatives


Support for SRS Salt Disposition Alternatives

Corrections to the previous Letter Report were sent as a Status Report to FIU and SRS. Additional information on experimental results will be included as FIU completes the experiment and forwards all of the data. All physical parameters, concentrations and volumes will then be compared to the predicted model results. The information received on the remaining undissolved salts within the column will be used for modeling heel dissolution processes.

Calculations on potassium-hydroxide-water, potassium-nitrate-water, and potassium nitrate-sodium nitrate-water systems in 1-molal sodium hydroxide and 1-molal potassium hydroxide at 25°C have been completed. Results are currently being examined and compared to literature values. Calculations continue on these systems for 3 molal sodium hydroxide and 3-molal potassium hydroxide at 25°C and 50°C. Additional literature information collection is underway for cesium, strontium, plutonium, and technetium.

On-line Analysis for Defense Waste Processing Facility

A slurry circulation system was further tested by collecting LIBS data by adding the various concentrations of Fe2O3 in water. This solution was circulated through the slurry system and spectra were recorded with a 0.5-m Spex spectrometer. These data were used to generate a Fe calibration curve. LIBS spectra were also recorded by spiking Fe2O3 into the original (base) RIC slurry sample. These data provided a Fe calibration curve only in the concentration range higher than the original sample. The results presented at the American Ceramic Society meeting with rotating a bottle slurry sample were quite encouraging. A decision was made to work further on a rotating bottle slurry sample system during the discussion with David Peeler, Sharon Mara, and Connie Herman in the ACerS meeting.

Support of Production of High Waste Loading Glasses in the DWPF

Progress on this task will be reported at a later date.

 

Task 5

HEPA Filter Performance Assurance


Regenerable HEPA Filter Performance Testing

During the month of May, tests were conducted to determine particle loss (KCl as test particulate) in the HEPA test stand due to settling in the aerosol generator tower and transfer line. In a separate experiment, the resulting particle size distributions of a 30% KCl solution dispersed by various nozzle types used with the DIAL aerosol generator on the HEPA test stand were compared. This was done in an effort to find a nozzle that would increase the particle count mean diameter relative to that currently attainable. The HEPA group also met with Kenneth Rubow from Mott Corporation and presented to him DIAL's filter testing capabilities and results of the evaluation of Mott powdered metal and metal fiber filters. Recommendations were made to the ASME Committee on Nuclear Air and Gas Treatment regarding the development of subsection FI of the AG-1 standard for HEPA metal media filters.

 

Inquiries may be addressed to:

Dr. John Plodinec, Director
205 Research Blvd.
Starkville, MS 39762-5932

 

Phone: 662-325-2105
FAX: 662-325-8465
Email: dial@dial.msstate.edu