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Executive SummaryThe Hanford Site in Washington State manages 177 underground storage tanks containing approximately 250,000 m 3 of waste generated during past defense reprocessing and waste management operations. These tanks contain a mixture of sludge, saltcake and supernatant liquids. The insoluble sludge fraction of the waste consists of metal oxides and hydroxides and contains the bulk of many radionuclides such as the transuranic components and 90 Sr. The saltcake, generated by extensive evaporation of aqueous solutions, consists primarily of dried sodium salts. The supernates consist of concentrated (5-15 M) aqueous solutions of sodium and potassium salts. The 177 storage tanks include 149 single-shell tanks (SSTs) and 28 double-shell tanks (DSTs).Ultimately the wastes need to be retrieved from the tanks for treatment and disposal. The SSTs contain minimal amounts of liquid wastes, and the Tank Operations Contractor is continuing a program of moving solid wastes from SSTs to interim storage in the DSTs. The Hanford DST system provides the staging location for waste feed delivery to the Department of Energy (DOE) Office of River Protection's (ORP) Hanford Tank Waste Treatment and Immobilization Plant (WTP). The WTP is being designed and constructed to pretreat and then vitrify a large portion of the wastes in Hanford's 177 underground waste storage tanks.The retrieval, transport, treatment and disposal operations involve the handling of a wide range of slurries. Solids in the slurry have a wide range of particle size, density and chemical characteristics. Depending on the solids concentration the slurries may exhibit a Newtonian or a non-Newtonian rheology.The extent of knowledge of the physical and rheological properties is a key component to the success of the design and implementation of the waste processing facilities. These properties are used in engineering calculations in facility designs. Knowledge of the waste properties is also necessary for the development and fabrication of simulants that are used in testing at various scales. The expense and hazards associated with obtaining and using actual wastes dictates that simulants be used at many stages in the testing and scale-up of process equipment. The results presented in this report should be useful for estimating process and equipment performance and provide a technical basis for development of simulants for testing.The purpose of this document is to provide an updated summary of the Hanford waste characterization data pertinent to safe storage, retrieval, transport and processing operations for both the tank farms and the WTP and thereby identify gaps in understanding and data. Important waste parameters for these operations are identified by examining examples of relevant mathematical models of selected phenomena including: The data sets in (UDS composition and particle density, UDS primary particle size and shape, UDS particle size distributions [PSDs], and estimated particle size and density distributions [PSDDs]) and Poloski et al. (2007) ...

Executive SummaryThe External Flowsheet Review Team (EFRT) expressed concern about the potential for Waste Treatment and Immobilization Plant (WTP) pipe plugging. Per the review's executive summary, "Piping that transports slurries will plug unless it is properly designed to minimize this risk. This design approach has not been followed consistently, which will lead to frequent shutdowns due to line plugging." To evaluate the potential for plugging, critical-velocity tests were performed on several physical simulants to determine if the design approach is conservative. Critical velocity is defined as the point where particles begin to deposit to form a moving bed of particles on the bottom of a straight horizontal pipe during slurry transport operations. The critical velocity depends on the physical properties of the particles, fluid, and system geometry.This report gives the results from critical-velocity testing and provides an indication of slurry stability as a function of fluid rheological properties and transport conditions that are typical of what the plant will see. The experimental results are compared to the WTP design guide on slurry-transport velocity in an effort to confirm minimum waste-velocity and flushing-velocity requirements as established by calculations and critical-velocity correlations in the design guide. The major findings of this testing are as follows:Experimental results indicate that for Newtonian fluids, the design guide is conservative. The design guide is based on the Oroskar and Turian (1980) correlation, a traditional industry-derived equation that focuses on particles larger than 100 m in size. Slurry viscosity has a greater effect on particles with a larger surface area to mass ratio, i.e. smaller particles. The increased viscous forces on small particles result in a smaller critical velocities. Since the Hanford slurry particles generally have large surface area to mass ratios, the reliance on such equations in the 24590-WTP-GPG-M-0058, Rev 0 design guide (Hall 2006) is conservative. Additionally, the use of the 95% percentile particle size as an input to this equation is conservative. The design guide specifies the use of the d 95 density, this term is ambiguous and needs clarification in the design guide. Nonetheless, this value is interpreted to mean the density of the d 95 particle. This density value is irrelevant for critical velocity calculations. Often this value is unknown, and Equation 1 of the 24590-WTP-GPG-M-0058, Rev 0 design guide (Hall 2006) will be used for design purposes. This equation calculates an average or composite density of all solids in the slurry. However, test results indicate that the use of an average particle density as an input to the equation is not conservative. Particle density has a large influence on the overall critical-velocity result returned by the correlation. The viscosity correlation used in the WTP design guide has been shown to be inaccurate for Hanford waste feed materials. Additionally, the recommendation of a 30% minimum margi...

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The actual testing activities were performed and reported separately in referenced documentation. Because of this, many of the required topics below do not apply and are so noted. Test ObjectivesThis section is not applicable. No testing was performed for this investigation. Test ExceptionsThis section is not applicable. No test specification as well as test exception applies to this investigation as there was no testing was performed. Results and Performance Against Success CriteriaThis section is not applicable. No success criteria were established as there was no testing performed for this investigation. Quality RequirementsSince This report is based on data from testing as referenced. The PNNL assumes that the data from these references has been fully reviewed and documented in accordance with the analysts' QA Programs. PNNL only analyzed data from the referenced documentation. At PNNL, the performed calculations, the documentation and reporting of results and conclusions were performed in accordance with the RPP-WTP Quality Assurance Manual (RPP-WTP-QA-003, QAM). Internal verification and validation activities were addressed by conducting an independent technical review of the final data report in accordance with PNNL procedure QA-RPP-WTP-604. This review verifies that the reported results are traceable, that inferences and conclusions are soundly based, and that the reported work satisfies the Test Specification Success Criteria. This review procedure is part of PNNL's RPP-WTP Quality Assurance Manual). Test ConditionsThe scope of the RWG effort is specified in the approved WTP issue response plan (24590-WTP-PL-ENG-06-0013) and defined in subcontractor change notice (SCN) 007 and Test Specification 24590-PTF-TSP-RT-06-007, Rev 0.Demonstrate the simulant properties used for testing bracket expected actual waste properties. For non-cohesive solids (Phase 1) this includes particle size, solids density, solids concentration, liquid density, and liquid viscosity. For cohesive solids (Phase 2) this includes bulk slurry density, particle size, particle density, slurry rheology (such as consistency and yield stress) and shear strength of settled, aged sediments, as well as settled layer (heel) thickness.Waste received at the WTP will be subject to a feed specification supporting plant design and as agreed to in an Interface Control Document. This report compiles the existing Hanford Tank Farm rheological data addressed in italicized text above and establishes expected ranges for these properties for as-retrieved Hanford Tank Farm wastes. Various processes will be performed on these retrieved wastes which are expected to alter these property ranges from the as-retrieved conditions. Simulant development activities should focus on the expected properties of the waste streams under such processing conditions. v Simulant UseThis section is not applicable. No testing was performed for this investigation.

Pulsed dye laser excitation spectroscopy of the 7F0----5D0 transition of Eu(III) reveals only a single peak as this ion is titrated into apocalmodulin. A titration based on the intensity of this transition shows that the first two Eu(III) ions bind quantitatively to two tight sites, followed by weaker binding (Kd = 2 microM) to two additional sites under conditions of high ionic strength (0.5 M KC1). This excitation experiment is also shown to be a general method for measuring contaminating levels of EDTA down to 0.2 microM in proton solutions. Experiments with Tb(III) using both direct laser excitation and indirect sensitization of Tb(III) luminescence through tyrosine residues in calmodulin also give evidence for two tight and two weaker binding sites (Kd = 2-3 microM). The indirect sensitization results primarily upon binding to the two weaker sites, implying that Tb(III) binds first to domains I and II, which are remote from tyrosine-containing domains III and IV. The 7F0----5D0 excitation signal of Eu(III) was used to measure the relative overall affinities of the tripositive lanthanide ions, Ln(III), across the series. Ln(III) ions at the end of the series are found to bind more weakly than those at the beginning and middle of the series. Eu(III) excited-state lifetime measurements in H2O and D2O reveal that two water molecules are coordinated to the Eu(III) at each of the four metal ion binding sites. Measurements of Förster-type nonradiative energy-transfer efficiencies between Eu(III) and Nd(III) in the two tight sites were carried out by monitoring the excited-state lifetimes of Eu(III) in the presence and absence of the energy acceptor ion Nd(III).(ABSTRACT TRUNCATED AT 250 WORDS)

The properties of reverse micelle and water-in-oil type microemulsion phases in supercritical xenon and ethane have been investigated. Structure, size, and the solvent environment of sodium bis(2-ethylhexyl) sulfosuccinate aggregates in these fluids were studied by using dynamic light scattering and view cell determinations of phase behavior. In addition, a new spectroscopic probe technique is reported for study of the solvent environment of the micelle and, indirectly, micelle size. The formation of a xenon-water clathrate in equilibrium with a xenon microemulsion is observed, and the effect of clathrate formation upon the polar core of reverse micelles in supercritical xenon is discussed. Properties such as size and solvent environment of the aqueous region under isothermal conditions are found to be somewhat dependent on the density of the continuous phase. Evidence of strongly pressure dependent micelle-micelle attractive interactions is presented. The properties of microemulsions in near-critical and supercritical fluids are compared to those in conventional liquid systems.

Reverse micelle and water-in-oil (w/o) microemulsion phases can be formed in near-critical and supercritical fluids, giving rise to uniquely pressure dependent phase behavior. The solvating power of reverse micelles formed from the surfactant sodium bis(2-ethylhexyl) sulfosuccinate (AOT) in fluids with moderate critical temperatures (e.g., ethane, propane, or xenon) depends largely upon the water-to-surfactant ratio of the micelle phase (Wm), which at large Wm can approach that of bulk water. The maximum water-to-surfactant ratio (W0), which defines the boundary between a one-phase and a two-phase fluid system (where a second, predominantly aqueous phase exists), is strongly pressure dependent. The physical size of a reverse micelle in one-phase AOT/H20 systems at constant Wm has been shown to be nearly independent of the continuous-phase identity and pressure. In contrast, the apparent hydrodynamic size increases dramatically as W0 is approached due to increased micelle-micelle attractive interactions (e.g., clustering). The maximum reverse micelle size (IEm <* diameter) increases with pressure for fluids such as ethane and propane, approaching Wm = 40, corresponding to a droplet size of ~17 nm. Significant micelle densities are obtained for two phase systems, even at relatively low pressure (<100 bar). These systems can be used to efficiently extract hydrophilic substances, including proteins, from dilute aqueous solution with substantial selectivity without the need for any chemical change to the system.