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One of the events postulated in the hazard analysis for the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak event involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids that behave as a Newtonian fluid. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and in processing facilities across the DOE complex.To expand the data set upon which the WTP accident and safety analyses were based, an aerosol spray leak testing program was conducted by Pacific Northwest National Laboratory (PNNL). PNNL's test program addressed two key technical areas to improve the WTP methodology (Larson and Allen 2010). The first technical area was to quantify the role of slurry particles in small breaches where slurry particles may plug the hole and prevent high-pressure sprays. The results from an effort to address this first technical area can be found in Mahoney et al. (2012). The second technical area was to determine aerosol droplet size distribution and total droplet volume from prototypic breaches and fluids, including sprays from larger breaches and sprays of slurries for which literature data are mostly absent. To address the second technical area, the testing program collected aerosol generation data at two scales, commonly referred to as small-scale and large-scale testing. The small-scale testing and resultant data are described in Mahoney et al. (2013), and the large-scale testing and resultant data are presented in Schonewill et al. (2012). In tests at both scales, simulants were used to mimic the relevant physical properties projected for actual WTP process streams.Examination of the results from the initial (subsequently referred to as Phase I) aerosol spray leak testing described in the preceding paragraph highlighted some uncertainties in evaluating aerosol generation that remained after the original scope of work was completed. Specifically, there was uncertainty with respect to aerosol behavior (namely aerosol release fraction and generation rates) for:  simulant(s) near the WTP rheological boundaries of (6 Pa/6 mPa·s and 30 Pa/30 mPa·s)  simulant(s) with solids loadings greater than 20 wt%  simulant(s) with a small solids fraction of particles that have a relatively high density  lower spray pressures (i.e., specifically 100 and 200 psig in the small-scale tests)  in-spray measurements.The need for additional (subsequently referred to as Phase II) aerosol spray leak testing was identified. The purpose of the study described in this report is to provide experimental data and analyses to supplement the results obtained during P...

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The tributyl phosphate sludge (TBP, Group 7) is the subject of this report. The Group 7 waste was anticipated to be high in phosphorus as well as aluminum in the form of gibbsite. Both are believed to exist in sufficient quantities in the Group 7 waste to address leaching behavior. Thus, the focus of the Group 7 testing was on the removal of both P and Al. The waste-type definition, archived sample conditions, homogenization activities, characterization (physical, chemical, radioisotope, and crystal habit), and caustic leaching behavior as functions of time, temperature, and hydroxide concentration are discussed in this report. Testing was conducted according to TP-RPP-WTP-467. ObjectivesThe test objectives are summarized in Table S.1 along with a discussion of how the objectives were met. Several objectives (in gray shading lighter than header shading) did not specifically apply to the scope provided in this report; they will be reported in companion reports as indicated in the controlling test plan. Y Group 7 contained a significant amount of P. The P behavior for the Group 7 composite during caustic leaching was characterized as a function of time, temperature, and free-hydroxide concentration.The P removal results can be found in Sections 3, 4, and 5.6) Determine the ultrafiltration flux before and after caustic and oxidative leaching over the operating range of solids concentrations during the leaching processes at 25°C when sufficient actual waste sample is available for testing the filtration behavior.Y Ultrafiltration (CUF) testing was performed on the Group 7 solids. The CUF testing was performed before leaching using slurries with both low-and high-solids contents. The high-solids slurry was obtained by blending wastes from AY-102 with the Group 7 slurry. Further CUF testing was performed after caustic leaching. During these tests, the ultrafiltration flux was determined as a function of transmembrane pressure and axial velocity. The CUF tests were conducted at ambient temperature. There was no oxidative leach performed on this waste type; therefore, there was no CUF testing done on post oxidative-leach materials.All the CUF testing results are discussed in Section 5. The solids characterization results are distributed throughout the report at the specific relevant sections. Test ExceptionsNo test exceptions applied to this work. Results and Performance Against Success CriteriaThe test plan delineated several success criteria, which are listed in Table S.2. Selected criteria were relevant to the test scope included in this report; the other criteria that are outside of the reported scope are shaded. Not applicable. The Group 7 sample did not have significant amounts of boehmite.5) The dissolution rate and the extent of dissolution of chromium in the actual waste solids are determined as a function of temperature and over a range of NaOH concentrations of interest to oxidative leaching. The NaMnO 4 dosage will be predetermined for the oxidation of the chromium in the waste solids. The associated uncert...

Testing SummaryThis is the final report in a series of eight reports summarizing the characterization, leach, and filtration testing of a wide variety of Hanford tank waste sludges. The information generated from this series is intended to supplement the Waste Treatment and Immobilization Plant (WTP) project understanding of actual waste behaviors associated with tank waste sludge processing through the pretreatment portion of the WTP. The work described in this report presents information on a high-iron waste form, specifically the ferrocyanide tank waste sludge. Iron hydroxide has been shown to pose technical challenges during filtration processing; the ferrocyanide tank waste sludge represented a good source of the high-iron matrix to test the filtration processing. Specifically discussed in this report are:  selection and compositing of tank waste sludge samples The effectiveness of each pretreatment process step was evaluated by following mass balances of key components (such as B, Cd, Cr, Pu, Ni, Mn, and Fe), demonstrating component (Al, P, Cr, Cs) removal, demonstrating filterability by evaluating filter-flux rates under various processing conditions (transmembrane pressure [TMP], crossflow velocities, and wt% undissolved solids [UDS]), filter fouling, and identifying potential issues for WTP. ObjectivesThe test objectives delineated in the controlling test plan (TP-RPP-WTP-467 (a) ) are provided in Table S.1 along with discussions of how the objectives were met. Several objectives (in gray shading lighter than header shading) did not specifically apply to the scope provided in this report; they have been reported in companion reports as indicated in the controlling test plan. Y Filter matrix testing was performed before leaching using slurries with both low (5.9 wt%) and high (13 wt%) solids contents. Further filter matrix testing at high-solids (15 wt%) content was performed after caustic leaching and washing of Group 8 solids. In this case, the leached and washed Group 8 solids were combined with caustic leached and washed solids from Group 7, tributyl phosphate sludge mixed with solids from AY-102. During these tests, the ultrafiltration flux was determined as a function of TMP and axial velocity. The filtration tests were conducted at ambient temperature.Dewatering curves were generated before and after caustic leaching and after each of four washes. An additional dewatering curve was generated after filter matrix testing in combination with Group 7/AY-102 solids to define filter flux as a function of wt% UDS and WTP-RPT-170, Rev. 0 xxii All the CUF testing results are discussed in Section 4. 7) Scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and XRD will be used to determine the primary mineral forms present for Al, Cr, and P and provide information to enable the correlation of these mineral forms to dissolution behavior.Y SEM and TEM coupled with EDS and XRD were performed on the washed Group 8 solids before caustic leaching. XRD...

SummaryThis document completes the requirements of Milestone 1-2, PNNL Draft Literature Review, discussed in the scope of work outlined in the EM-31 Support Project task plan WP-2.3.6-2010-1. The focus of task WP-2.3.6 is to improve the U.S. Department of Energy's (DOE's) understanding of filtration operations for high-level waste (HLW) to enhance filtration and cleaning efficiencies, thereby increasing process throughput and reducing the sodium demand (through acid neutralization). Developing the processes for fulfilling the cleaning/backpulsing requirements will result in more efficient operations for both the Hanford Tank Waste Treatment and Immobilization Plant (WTP) and the Savannah River Site (SRS), thereby increasing throughput by limiting cleaning cycles.The purpose of this document is to summarize Pacific Northwest National Laboratory's (PNNL's) literature review of historical filtration testing at the laboratory and of testing found in peer-reviewed journals. Eventually, the contents of this document will be merged with a literature review by SRS to produce a summary report for DOE of the results of previous filtration testing at the laboratories and the types of testing that still need to be completed to address the questions about improved filtration performance at WTP and SRS. To this end, this report presents 1) a review of the current state of crossflow filtration knowledge available in the peer-reviewed literature, 2) a detailed review of PNNLrelated filtration studies specific to the Hanford site, and 3) an overview of current waste filtration models developed by PNNL and suggested avenues for future model development.This extensive review provides a starting point to help achieve the ultimate goal of the current project, which is to identify technologies such as modifications to the process (e.g., reconfiguration of the filter geometry or changes to operational techniques) or the use of physical property modifiers that increase the sustainability of the filter process. Overall, two avenues of future model development are recommended: 1) determination of long-term filtration dynamics of actual waste and waste simulant slurries and 2) evaluation of the impact of solution chemistry on the rate of filtration and filter fouling. A better understanding of these long-term fouling dynamics and solution chemistry effects will help in developing better predictive models and improved process optimization.v