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Selecting Compositions for Phase 1 of the Product Consistency Test (PCT) Assessment Study

Description: The purpose of this task is to generate the glass property/composition data and model necessary for enhancing operational processing windows. This effort is intended to be both generally applicable to all Department of Energy (DOE) High-Level Waste (HLW) glasses and specific to individual waste processing plants such as the DWPF and the planned High-Level and Low Activity Waste (HLW and LAW) plants at Hanford. Phase 1 consists of determining the glass compositional region where the existing durability model is not dependable in identifying durable glasses. Phase 2 will be devoted to developing a method of ensuring that durable glass compositions are not excluded from processing.
Date: October 15, 2002
Creator: Cozzi, A.D.
Partner: UNT Libraries Government Documents Department

Durability Assessment of High Alkali Glasses in Support of the Accelerated Clean-Up Mission: Experimental Results of the ''ND'' Glasses

Description: In support of accelerated mission goals, glass formulation efforts have been focused on melt rate, waste loading, and waste throughput for the DWPF. With respect to melt rate, the general trend to improve melt rate has been to enhance the total alkali concentration in the glass system by increasing the alkali concentration in the frit, utilizing (or targeting) a less washed sludge, or using a combination of the two. Cozzi et al. (2002) defined thirty-one glasses that intentionally challenged either the current durability model over an extremely broad compositional region or the Salkali and Al2O3 criteria proposed by Herman et al. (2002). These glasses were batched, melted, and subjected to the PCT. In this report, the results of both compositional analysis and PCT response are discussed.
Date: October 29, 2003
Creator: Cozzi, A. D.
Partner: UNT Libraries Government Documents Department

Technical Status Report on the Effect of Phosphate and Aluminum on the Development of Amorphous Phase Separation in Sodium

Description: The objective of the Tank Focus Area ''Optimize Waste Loading'' task is to enhance the definition of the acceptable processing window for high-level waste vitrification plants. One possible manner in which the acceptable processing window may be enhanced is by reducing the uncertainty of various compositional/property models through a specifically defined experimental plan. A reduction in model uncertainty can reduce limitations on current acceptance constraints and may allow for a larger processing or operational window. Enhanced composition/property model predictions coupled with an increased waste loading may decrease the processing time and waste glass disposal costs (i.e., overall lifecycle costs). One of the compositional/property models currently being evaluated by the Tanks Focus Area is related to the development of amorphous phase separation in multi-component borosilicate glasses.Described in this report is the current status for evaluating the effect of phosphorus and alumina on both simple sodium borosilicate and high-level waste glasses on the formation of amorphous phase separation. The goal of this subtask is to increase the understanding of the formation of phase separation by adding significant amounts (3-5 wt. percent) of phosphorus and alumina to well-characterized glasses. Additional scope includes evaluating the effects of thermal history on the formation of amorphous phase separation and durability of select glasses.The development of data, understanding, and quantitative description for composition and kinetic effects on the development of amorphous phase separation will continue in FY99. This effort will provide insight into the compositional and thermal effects on phase stability and will lead to a better understanding of the methods used to predict the development of amorphous phase separation in HLW glasses.
Date: November 3, 1998
Creator: Cozzi, A.D.
Partner: UNT Libraries Government Documents Department

Volatile impurities in the ceramic form for the Plutonium Immobilization Project (PIP)

Description: The primary goal for the impurity tests performed at SRS was to determine the maximum level of volatile impurities that can be accommodated into the ceramic form without significantly affecting product properties. The properties investigated in this study are the apparent porosity and the phase assemblage.
Date: March 2, 2000
Creator: Cozzi, A.D.
Partner: UNT Libraries Government Documents Department

Volatile Impurities in the Plutonium Immobilization Ceramic Wasteform

Description: Approximately 18 of the 50 metric tons of plutonium identified for disposition contain significant quantities of impurities. A ceramic waste form is the chosen option for immobilization of the excess plutonium. The impurities associated with the stored plutonium have been identified (CaCl2, MgF2, Pb, etc.). For this study, only volatile species are investigated. The impurities are added individually. Cerium is used as the surrogate for plutonium. Three compositions, including the baseline composition, were used to verify the ability of the ceramic wasteform to accommodate impurities. The criteria for evaluation of the effect of the impurities were the apparent porosity and phase assemblage of sintered pellets.
Date: October 15, 1999
Creator: Cozzi, A.D.
Partner: UNT Libraries Government Documents Department

Technical Status Report on the Effect of Phosphate and Aluminum on the Development of Amorphous Phase Separation in Sodium Borosilicate Glasses

Description: The objective of the Tank Focus Area ''Optimize Waste Loading'' task is to enhance the definition of the acceptable processing window for high-level waste vitrification plants. One possible manner in which the acceptable processing window may be enhanced is by reducing the uncertainty of various compositional/property models through a specifically defined experimental plan. A reduction in model uncertainty can reduce limitations on current acceptance constraints and may allow for a larger processing or operational window. Enhanced composition/property model predictions coupled with an increased waste loading may decrease the processing time and waste glass disposal costs (i.e., overall lifecycle costs). One of the compositional/property models currently being evaluated by the Tanks Focus Area is related to the development of amorphous phase separation in multi-component borosilicate glasses.Described in this report is the current status for evaluating the effect of phosphorus and alumina on both simple sodium borosilicate and high-level waste glasses on the formation of amorphous phase separation. The goal of this subtask is to increase the understanding of the formation of phase separation by adding significant amounts (3-5 wt. percent) of phosphorus and alumina to well-characterized glasses. Additional scope includes evaluating the effects of thermal history on the formation of amorphous phase separation and durability of select glasses.The development of data, understanding, and quantitative description for composition and kinetic effects on the development of amorphous phase separation will continue in FY99. This effort will provide insight into the compositional and thermal effects on phase stability and will lead to a better understanding of the methods used to predict the development of amorphous phase separation in HLW glasses.
Date: December 3, 1998
Creator: Cozzi, A. D.
Partner: UNT Libraries Government Documents Department

Plutonium Immobilization Project (PIP) Precursor Material Calcine Temperature

Description: As a result of the end of the Cold War, approximately 50 metric tons of plutonium are no longer needed and have been identified for disposition. A ceramic waste form is the chosen option for immobilization of the excess plutonium. The plutonium ceramic form then will be encased in high-level waste glass using can-in-canister technology for final disposition. The precursor materials are the non-radioactive components that are added to the plutonium feed stream to form the desired phases in the immobilization product. The precursor materials are blended and calcined prior to being mixed with the plutonium feed stream. The purpose of the calcine step is to remove any physical or chemical water retained in the precursors and convert any hydroxides or carbonates to the oxides. Initially, a temperature of 750 degrees C for a period of one hour was chosen for the calcining of the precursors. In this effort, several different calcine temperatures were investigated to evaluate the effect on initial phase formation (in the calcined precursors), thermal expansion of the pressed pellets during heating, and mineralogy and porosity of the final product.
Date: July 29, 1999
Creator: Cozzi, A.D.
Partner: UNT Libraries Government Documents Department

Characterization of DWPF Melter One Glasses

Description: The Defense Waste Processing Facility's first melter operated continuously for more than eight years. In November 2002 it was decided to replace the melter. As part of the decommissioning and replacement of the first DWPF melter, three samples were collected from the melter, one from the melter surface and two from the core sampler. The melter samples were analyzed for chemical composition and crystal content.
Date: December 15, 2003
Creator: Cozzi, A.D.
Partner: UNT Libraries Government Documents Department

Slurry Fed Melt Rate Furnace Runs to Support Glass Formulation Development for INEEL Sodium-Bearing Waste

Description: The Savannah River Technology Center (SRTC) in conjunction with the Pacific Northwest National Laboratory (PNNL) is developing frit compositions and adjusting waste loading to minimize the potential of forming a sulfate salt during melter processing. The overall objective of the glass formulation effort is to retain all of the sulfur from the melter feed into the glass. The objective of retaining all of the sulfur in the glass is being driven by the baseline flowsheet assumption that sulfur partitioned to the offgas will be recycled back to the melter.
Date: July 8, 2002
Creator: Cozzi, A.D.
Partner: UNT Libraries Government Documents Department

Impact Of Standing Bleed Water On Saltstone Placement

Description: The amount of water present during placement and subsequent curing of saltstone has the potential to impact several properties important for grout quality. An active drain water system can remove residual standing water and expose the surface of the placed saltstone to air. Oxidation of the saltstone may result in an increase in the leachability of redox sensitive elements. A dry surface can lead to cracking, causing an increase in hydraulic conductivity. An inactive drain water system can allow standing water that generates unnecessary hydrostatic head on the vault walls. Standing water that cannot be removed via the drain system will be available for potential incorporation into subsequent grout placements. The objective of this work is to study the impact of standing water on grout quality pertaining to disposal units. A series of saltstone mixes were prepared, and cured at ambient temperature to evaluate the impact of standing water on saltstone placement. The samples were managed to control drying effects on leachability by either exposing or capping the samples. The water to premix ratio was varied to represent a range of processing conditions. Samples were analyzed for density, leachability, and hydraulic conductivity. A monolith of each composition was cut into four sections to analyze the homogeneity of the sample with respect to vertical position within the sample. The density of each section was measured by two methods, helium pycnometry and by ASTM 642-06. The results show a trend of increasing density with increasing depth in the samples. This effect is more pronounced with the inclusion of excess bleed water and indicative of increased settling. The leachability of the eight different samples was analyzed by ANS/ANSI 16.1 method. These results indicate that drying of the saltstone during curing leads to decreased Leachability Indices (indicative of more release) for potassium, sodium, rhenium, ...
Date: September 28, 2012
Creator: Cozzi, A. D. & Pickenheim, B. R.
Partner: UNT Libraries Government Documents Department

Impact Of Standing Water On Saltstone Placement II - Hydraulic Conductivity Data

Description: The amount of water present during placement and subsequent curing of saltstone has the potential to impact several properties important for grout quality. An active drain water system can remove residual standing water and expose the surface of the placed saltstone to air. Oxidation of the saltstone may result in an increase in the leachability of redox sensitive elements. A dry surface can lead to cracking, causing an increase in hydraulic conductivity. An inactive drain water system can allow standing water that generates unnecessary hydrostatic head on the vault walls. Standing water that cannot be removed via the drain system will be available for potential incorporation into subsequent grout placements. The objective of this work is to study the impact of standing water on grout quality pertaining to disposal units. A series of saltstone mixes was prepared and cured at ambient temperature to evaluate the impact of standing water on saltstone placement. The samples were managed to control drying effects on leachability by either exposing or capping the samples. The water to premix ratio was varied to represent a range of processing conditions. Samples were analyzed for density, leachability, and hydraulic conductivity. Report SRNL-STI-2012-00546 was issued detailing the experimental procedure, results, and conclusions related to density and leachability. In the previous report, it was concluded that: density tends to increase toward the bottom of the samples. This effect is pronounced with excess bleed water; drying of the saltstone during curing leads to decreased Leachability Index (more leaching) for potassium, sodium, rhenium, nitrite, and nitrate; there is no noticeable effect on saltstone oxidation/leachability by changing the water to premix ratio (over the range studied), or by pouring into standing water (when tested up to 10 volume percent). The hydraulic conductivity data presented in this report show that samples cured exposed to ...
Date: December 6, 2012
Creator: Cozzi, A. D. & Pickenheim, B. R.
Partner: UNT Libraries Government Documents Department

Analytical Results Of MOX Colemanite Concrete Sample PBC-44.2

Description: The Mixed Oxide Fuel Fabrication Facility (MFFF) will use colemanite bearing concrete neutron absorber panels credited with attenuating neutron flux in the criticality design analyses and shielding operators from radiation. The Savannah River National Laboratory is tasked with measuring the total density, partial hydrogen density, and partial boron density of the colemanite concrete. Sample PBC-44.2 was received on 9/20/2012 and analyzed. The average total density measured by the ASTM method C 642 was 2.03 g/cm{sup 3}, within the lower bound of 1.88 g/cm{sup 3}. The average partial hydrogen density was 6.64E-02 g/cm{sup 3} as measured using method ASTM E 1311 and met the lower bound of 6.04E-02 g/cm{sup 3}. The average measured partial boron density was 1.97E-01 g/cm{sup 3} which met the lower bound of 1.65E-01 g/cm{sup 3} measured by the ASTM C 1301 method.
Date: October 18, 2012
Creator: Cozzi, A. D.; Best, D. R. & Reigel, M. M.
Partner: UNT Libraries Government Documents Department

ANALYTICAL RESULTS OF MOX COLEMANITE CONCRETE SAMPLE POURED JULY 25, 2012 - CURED 28 DAYS

Description: The Mixed Oxide Fuel Fabrication Facility (MFFF) will use Colemanite bearing concrete neutron absorber panels credited with attenuating neutron flux in the criticality design analyses and shielding operators from radiation. The Savannah River National Laboratory is tasked with measuring the total density, partial hydrogen density, and partial boron density of the colemanite concrete. Samples 8.1.2, 8.2.2, 8.3.2, and 8.4.2 were received on 8/1/2012 and analyzed after curing for 28 days. The average total density measured by the ASTM method C 642 was 2.09 g/cm{sup 3}, within the lower bound of 1.88 g/cm{sup 3}. The average partial hydrogen density was 7.48E-02 g/cm{sup 3} as measured using method ASTM E 1311 and met the lower bound of 6.04E-02 g/cm{sup 3}. The average measured partial boron density was 1.71E-01 g/cm{sup 3} which met the lower bound of 1.65E-01 g/cm{sup 3} measured by the ASTM C 1301 method.
Date: September 18, 2012
Creator: Cozzi, A. D.; Best, D. R. & Reigel, M. M.
Partner: UNT Libraries Government Documents Department

Analytical Results of DWPF Glass Sample Taken During Pouring of Canister S01913: Summary Report

Description: In order to comply with the Waste Acceptance Product Specifications in Sludge Batch 2, Savannah River National Laboratory personnel performed characterization analysis of the Defense Waste Processing Facility (DWPF) radioactive glass pour stream sample taken during filling of Canister S01913. This report summarizes results of the characterization that indicate that the DWPF produced glass is significantly more durable than the Environmental Assessment glass. Results and further details are documented in the report, ''Analytical Results of DWPF Glass Sample Taken during Pouring of Canister S01913'', WSRC-TR-2004-00316, Rev. 2, (2005).
Date: October 1, 2005
Creator: Cozzi, A. D.; Bibler, N.E. & Bannochie, C. J.
Partner: UNT Libraries Government Documents Department

Process Control for Simultaneous Vitrification of Two Mixed Waste Streams in the Transportable Vitrification System

Description: Two highly variable mixed (radioactive and hazardous) waste sludges were simultaneously vitrified in an EnVitCo Transportable Vitrification System (TVS) deployed at the Oak Ridge Reservation. The TVS was the result of a cooperative effort between the Westinghouse Savannah River Company and EnVitCo to design and build a transportable melter capable of vitrifying a variety of mixed low level wastes.The two waste streams for the demonstration were the dried B and C Pond sludges at the K-25 site and waste water sludge produced in the Central Neutralization Facility from treatment of incinerator blowdown. Large variations occurred in the sodium, calcium, silicon, phosphorus, fluorine and iron content of the co- blended waste sludges: these elements have a significant effect on the process ability and performance of the final glass product. The waste sludges were highly reduced due to organics added during processing, coal-pile runoff (coal and sulfides), and other organics, including wood chips. A batch-by-batch process control model was developed to control glass viscosity, liquidus, and reduction/oxidation, assuming that the melter behaved as a Continuously Stirred Tank Reactor.
Date: May 1998
Creator: Cozzi, A. D.; Jantzen, C. M.; Brown, K. G. & Cicero-Herman, C.
Partner: UNT Libraries Government Documents Department

Characterization of Defense Waste Processing Facility (DWPF) Glass and Deposit Samples from Melter No.2

Description: The Defense Waste Processing Facility (DWPF) Engineering requested characterization of three glass samples that were taken from Melter number 2 after the waste loading had been increased, e.g. after the new quasicrystalline liquidus model had been implemented and after DWPF switched from processing with Frit 200 to Frit 320. These samples were taken after DWPF observed very rapid buildup of deposits in the upper pour spout bore and on the pour spout insert while processing the high waste loading (approximate 38 wt percent feedstock). Rapid deposition in these locations had not occurred prior to this and, in turn, stopped after waste loading decreased. These samples were evaluated at SRTC using various analytical techniques for potential impacts on pouring problems recently experienced by the DWPF.
Date: July 8, 2004
Creator: Jantzen, Carol M.; Cozzi, A. D. & Bibler, N. E.
Partner: UNT Libraries Government Documents Department

Radioactive Demonstrations Of Fluidized Bed Steam Reforming (FBSR) With Hanford Low Activity Wastes

Description: Several supplemental technologies for treating and immobilizing Hanford low activity waste (LAW) are being evaluated. One immobilization technology being considered is Fluidized Bed Steam Reforming (FBSR) which offers a low temperature (700-750?C) continuous method by which wastes high in organics, nitrates, sulfates/sulfides, or other aqueous components may be processed into a crystalline ceramic (mineral) waste form. The granular waste form produced by co-processing the waste with kaolin clay has been shown to be as durable as LAW glass. The FBSR granular product will be monolithed into a final waste form. The granular component is composed of insoluble sodium aluminosilicate (NAS) feldspathoid minerals such as sodalite. Production of the FBSR mineral product has been demonstrated both at the industrial, engineering, pilot, and laboratory scales on simulants. Radioactive testing at SRNL commenced in late 2010 to demonstrate the technology on radioactive LAW streams which is the focus of this study.
Date: October 22, 2012
Creator: Jantzen, C. M.; Crawford, C. L.; Burket, P. R.; Bannochie, C. J.; Daniel, W. G.; Nash, C. A. et al.
Partner: UNT Libraries Government Documents Department

Measurements of Flammable Gas Generation from Saltstone Containing Actual Tank 48H Waste (Interim Report)

Description: The Savannah River National Laboratory was tasked with determining the benzene release rates in saltstone prepared with tetraphenylborate (TPB) concentrations ranging from 30 mg/L to 3000 mg/L in the salt fraction and with test temperatures ranging from ambient to 95 C. Defense Waste Processing Facility Engineering (DWPF-E) provided a rate of benzene evolution from saltstone of 2.5 {micro}g/L/h saltstone (0.9 {micro}g/kg saltstone/h [1.5 {micro}g/kg saltstone/h x 60%]) to use as a Target Rate of Concern (TRC). The evolution of benzene, toluene, and xylenes from saltstone containing actual Tank 48H salt solution has been measured as a function of time at several temperatures and concentrations of TPB. The Tank 48H salt solution was aggregated with a DWPF recycle simulant to obtain the desired TPB concentrations in the saltstone slurry. The purpose of this interim report is to provide DWPF-E with an indication of the trends of benzene evolution. The data presented are preliminary; more data are being collected and may alter the preliminary results. A more complete description of the methods and materials will be included in the final report. The benzene evolution rates approximately follow an increasing trend with both increasing temperature and TPB concentration. The benzene release rates from 1000 mg/L TPB at 95 C and 3000 mg/L TPB at 75 C and 95 C exceeded the recovery-adjusted 0.9 mg/kg saltstone/h TRC (2.5 {micro}g/L saltstone/h), while all other conditions resulted in benzene release rates below this TRC. The toluene evolution rates for several samples exceeded the TRC initially, but all dropped below the TRC within 2-5 days. The toluene emissions appear to be mainly dependent on the fly ash and are independent of the TPB level, indicating that toluene is not generated from TPB.
Date: June 1, 2005
Creator: Cozzi, A. D.; Crowley, D. A.; Duffey, J. M.; Eibling, R. E.; Jones, T. M.; Marinik, A. R. et al.
Partner: UNT Libraries Government Documents Department

Radioactive Demonstration Of Mineralized Waste Forms Made From Hanford Low Activity Waste (Tank Farm Blend) By Fluidized Bed Steam Reformation (FBSR)

Description: The U.S. Department of Energy’s Office of River Protection (ORP) is responsible for the retrieval, treatment, immobilization, and disposal of Hanford’s tank waste. A key aspect of the River Protection Project (RPP) cleanup mission is to construct and operate the Hanford Tank Waste Treatment and Immobilization Plant (WTP). The WTP will separate the tank waste into high-level and low-activity waste (LAW) fractions, both of which will subsequently be vitrified. The projected throughput capacity of the WTP LAW Vitrification Facility is insufficient to complete the RPP mission in the time frame required by the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement (TPA), i.e. December 31, 2047. Supplemental Treatment is likely to be required both to meet the TPA treatment requirements as well as to more cost effectively complete the tank waste treatment mission. The Supplemental Treatment chosen will immobilize that portion of the retrieved LAW that is not sent to the WTP’s LAW Vitrification facility into a solidified waste form. The solidified waste will then be disposed on the Hanford site in the Integrated Disposal Facility (IDF). Fluidized Bed Steam Reforming (FBSR) offers a moderate temperature (700-750°C) continuous method by which LAW can be processed irrespective of whether the waste contain organics, nitrates, sulfates/sulfides, chlorides, fluorides, volatile radionuclides or other aqueous components. The FBSR technology can process these wastes into a crystalline ceramic (mineral) waste form. The mineral waste form that is produced by co-processing waste with kaolin clay in an FBSR process has been shown to be comparable to LAW glass, i.e. leaches Tc-99, Re and Na at <2g/m2 during ASTM C1285 (Product Consistency) durability testing. Monolithing of the granular FBSR product was investigated to prevent dispersion during transport or burial/storage. Monolithing in an inorganic geopolymer binder, which is amorphous, macro-encapsulates the granules, and ...
Date: August 21, 2013
Creator: Jantzen, C. M.; Crawford, C. L.; Bannochie, C. J.; Burket, P. R.; Cozzi, A. D.; Daniel, W. E. et al.
Partner: UNT Libraries Government Documents Department

Radioactive Demonstration Of Mineralized Waste Forms Made From Hanford Low Activity Waste (Tank SX-105, Tank AN-103, And AZ-101/102) By Fluidized Bed Steam Reformation (FBSR)

Description: Fluidized Bed Steam Reforming (FBSR) is a robust technology for the immobilization of a wide variety of radioactive wastes. Applications have been tested at the pilot scale for the high sodium, sulfate, halide, organic and nitrate wastes at the Hanford site, the Idaho National Laboratory (INL), and the Savannah River Site (SRS). Due to the moderate processing temperatures, halides, sulfates, and technetium are retained in mineral phases of the feldspathoid family (nepheline, sodalite, nosean, carnegieite, etc). The feldspathoid minerals bind the contaminants such as Tc-99 in cage (sodalite, nosean) or ring (nepheline) structures to surrounding aluminosilicate tetrahedra in the feldspathoid structures. The granular FBSR mineral waste form that is produced has a comparable durability to LAW glass based on the short term PCT testing in this study, the INL studies, SPFT and PUF testing from previous studies as given in the columns in Table 1-3 that represent the various durability tests. Monolithing of the granular product was shown to be feasible in a separate study. Macro-encapsulating the granular product provides a decrease in leaching compared to the FBSR granular product when the geopolymer is correctly formulated.
Date: September 18, 2013
Creator: Jantzen, C. M.; Crawford, C. L.; Bannochie, C. J.; Burket, P. R.; Cozzi, A. D.; Daniel, W. E. et al.
Partner: UNT Libraries Government Documents Department