Download or read book Sulfate Solubility Limit Verification for DWPF Sludge Batch 7A written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: During processing at the Defense Waste Processing Facility (DWPF), high sulfate concentrations in the feed are a concern to DWPF as it can lead to the formation of a detrimental, sulfate-rich, molten salt phase on the surface of the glass melt pool. To avoid these issues, a sulfate concentration limit was implemented into the Product Composition Control System (PCCS). Related to SB7a frit development efforts, the Savannah River National Laboratory (SRNL) assessed the viability of using the current 0.6 wt % SO42− limit set for SB6 (in glass) and the possibility of increasing the SO42− solubility limit in PCCS to account for anticipated sulfur concentrations, targeted waste loadings, and inclusion of secondary streams (e.g., Actinide Removal Process (ARP)) with two recommended frits (Frit 418 and Frit 702) for SB7a processing. For a nominal SB7a blend with a 63 inch SB6 heel remaining in Tank 40 (projection SB7a-63), a 0.60 wt% SO42− in glass limit was determined for waste loadings of 34 wt% up to 40 wt% with Frit 418 based on crucible melts with batched chemicals. SRNL also examined the inclusion of ARP for the same blending scenario (SB7a-63-ARP) with Frit 418 and at least a 0.6 wt% SO42− level, and waste loadings of 34 wt% to 40 wt% were also acceptable. When a visible yellow and/or white sulfate salt layer was visible on the surface of any cooled glass, it was assumed to have surpassed the solubility limit of SO42− for that particular composition. All of the glasses fabricated at these concentrations did not exhibit a sulfate rich salt layer on the surface of the glass melt and retained the majority of the batched SO42−. At higher levels of SO42− 'spiked' into the projected sludge compositions over the aforementioned interval of waste loadings, with Frit 418, low viscosity sulfur layers were observed on the surface of glass melts which confirm exceeding the solubility limit. The same sludge scenarios were also tested with Frit 702 and all glasses did not exhibit sulfur layers on the surfaces of the glass melts at spiking levels up to 0.80 wt% SO42−. An ultimate SO42− limit was not defined with Frit 702, but if projected SO42− concentrations are expected to increase with the onset of SB7a processing, a higher limit is achievable with Frit 702 than is achievable with Frit 418. Given the anticipated concentration of SO42− for SB7a, a SO42− limit of 0.6 wt % SO42− is recommended for processing using Frit 418. Once the confirmed SB7a composition is known and should a higher limit be needed, SRNL can re-evaluate the limit based on the actual composition and provide an updated recommendation. It has been observed that higher levels of SO42− in glass can be retained with compositional changes to the frit, as was demonstrated by the glasses fabricated using Frit 702. SRNL also recommends the continuation of studies to define a more 'global' sulfate concentration limit to account for future sludge batch composition uncertainties.

Download or read book Sulfate Solubility Limit Verification for DWPF Sludge Batch 7B written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this study was to determine a sulfate solubility limit in glass for Sludge Batch 7b (SB7b). The SB7b composition projection provided by Savannah River Remediation (SRR) on May 25, 2011 was used as the basis for formulating glass compositions to determine the sulfate limit. Additions of Na2O to the projected sludge composition were made by the Savannah River National Laboratory (SRNL) due to uncertainty in the final concentration of Na2O for SB7b, which is dependent on washing effectiveness and the potential need to add NaOH to ensure an acceptable projected operating window. Additions of 4, 6, and 8 wt % Na2O were made to the nominal May 25, 2011 composition projection. An updated SB7b composition projection was received from SRR on August 4, 2011. Due to compositional similarities, no additional experimental work using the August 4, 2011 compositions was considered to be necessary for this study. Both Frit 418 and Frit 702 were included in this study. The targeted sulfate (SO42−) concentrations of the study glasses were selected within the range of 0.6 to 0.9 wt % in glass. A total of 52 glass compositions were selected based on the compositional variables of Na2O addition, Actinide Removal Process (ARP) stream addition, waste loading, frit composition, and sulfate concentration. The glasses were batched, melted, and characterized following SRNL procedures. Visual observations were recorded for each glass after it cooled and used as in indicator of sulfur retention. Representative samples of each of the glasses fabricated were subjected to chemical analysis to determine whether the targeted compositions were met, as well as to determine the quantity of sulfate that was retained after melting. In general, the measured composition data showed that there were only minor issues in meeting the targeted compositions for the study glasses, and the measured sulfate concentrations for each study glass were within 10% of the targeted values. The results for the SB7b glasses fabricated with Frit 418 showed an apparent trend of increasing sulfate retention with increasing Na2O additions to the 5/25/11 sludge projection. This trend appears contradictory to other recent studies of sulfate retention in Defense Waste Processing Facility (DWPF) type glasses. Additional apparent contradictions to this trend were found in the data collected in the present study. Overall, the results for the SB7b sulfate study glasses with Frit 418 and the 5/25/11 projection with Na2O additions showed that subtle changes in this complex glass composition impacted the degree of sulfate retention. These results do however provide confidence that a 0.6 wt % sulfate limit in glass is warranted for Frit 418 with the SB7b compositions evaluated in this study. The results for the SB7b glasses fabricated with Frit 702 are consistent with those of the previous SB7a study in that Frit 702 allowed for higher sulfate retention as compared to Frit 418 for the same sludge compositions. It is recommended that the DWPF implement a sulfate concentration limit of 0.6 wt % in glass for SB7b processing with Frit 418. If a higher than projected sulfate concentration is measured when SB7b processing begins (i.e., if a sulfate concentration higher than 0.6 wt % becomes necessary to achieve targeted waste loadings), DWPF should consider a transition to Frit 702. The sulfate limit could likely be raised to 0.8 wt % by transitioning to this frit. However, if DWPF considers transitioning from Frit 418 to Frit 702, additional glasses should be fabricated to confirm this higher limit due to the issues with incorrect B2O3 concentrations for some of the glasses made with Frit 702 in this study. There are several factors other than sulfate retention that must also be carefully considered prior to changing frit compositions.

Download or read book An Assessment of the Sulfate Solubility Limit for the FRIT 418 Sludge Batch 2 written by and published by . This book was released on 2004 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this report is to establish a ''single point'' sulfate solubility limit or constraint for the Frit 418 - Sludge Batch 2/3 (SB2/3) system. Based on the results of this study, it is recommended that the glass limit in the Product Composition Control System (PCCS) for the Frit 418 - SB2/3 system be set at 0.60 wt%. The new limit has been set based solely on sealed crucible scale data and does not take credit or account for potential volatilization that may occur in the Defense Waste Processing Facility (DWPF) melter. Although the limit is established based on sealed crucible scale tests, supplementary testing using the Slurry-Fed Melt Rate Furnace (SMRF) provides a measure of confidence that applying the 0.6 wt% limit in PCCS will prevent the formation of a salt layer in the melter. The critical data point that was used to define the solubility limit for this system was from a ''spiked'' 30% waste loading (WL) glass targeting 0.65 wt%. The measured content in this glass was 0.62 wt%. Applying the Savannah River Technology Center - Mobile Laboratory (SRTCML) inductively coupled plasma (ICP) atomic emission spectroscopy (AES) uncertainties to establish a solubility limit for the Frit 418 - SB2/3 system of 0.60 wt% (in glass) provides a ''single point'' limit that covers the anticipated WL interval of interest. It is noted that there are glasses above the 0.60 wt% limit that were homogeneous, thus reinforcing the theory of a compositional effect on solubility within this specific system. In general, higher solubilities were observed at higher targeted waste loadings.

Download or read book Initial Sulfate Solubility Study for Sludge Batch 4 SB4 written by T. Lorier and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this task is to provide the Defense Waste Processing Facility (DWPF) of the Savannah River Site (SRS) with an assessment of the viability of using the current 0.6 wt% SO{sub 4}{sup =} limit (in glass) and/or the possibility of increasing the SO{sub 4}{sup =} solubility limit to account for anticipated sulfur concentrations in Sludge Batch 4 (SB4). The 0.6 wt% SO{sub 4}{sup =} limit was implemented for processing of Frit 418-Sludge Batch 3 (SB3) to avoid the formation of sulfate inclusions in the glass and/or the formation of a molten sulfate-rich phase on the melt pool in the DWPF melter. The presence of such a phase on the surface of the melt pool increases corrosion rates of melter components, enhances the potential for steam excursions in a slurry-fed waste glass melter, and creates the potential for undesirable current paths that could deplete energy delivered to the melter due to the electrical conductivity of the molten salt layer. This suite of sulfate-solubility tests began by testing the 1200-canister, 2nd transfer case for SB4 (as defined by Lilliston and Shah, 2004)--based on this being the most conservative (having the highest predicted viscosity when coupled with specific frits, it could potentially have the greatest impact on SO{sub 4}{sup =} solubility) blending scenario of SB4 with the heel of SB3 for SO{sub 4}{sup =} solubility. Frits 320 and 418 were tested with SB4 and the tests indicated that at the current SO{sub 4}{sup =} limit (in glass) and the tested waste loadings (30% and 40%), neither Frit 320 nor Frit 418 could be utilized with SB4 (for the 1200-canister, 2nd transfer case composition originally provided). More specifically, SO{sub 4}{sup =} was observed on the surface with the SB4 composition and Frit 320 at 40% waste loading (WL) and 0.6 wt% SO{sub 4}{sup =}, and with Frit 418 at 30% and 40% WL and 0.5 wt% SO{sub 4}{sup =}. As alternative frits were being developed--Frits 447, 448, and 449, that contained CaO and/or V2O5 to enhance SO{sub 4}{sup =} solubility based on suggestions of previous studies--testing began of the 1100-canister, 1st transfer case for SB4 (from Lilliston, 2005), which is the baseline flowsheet for the DWPF. The results of the study with the revised compositions have indicated that the SO{sub 4}{sup =} solubility limit in the DWPF of 0.6 wt% can be applicable for the 1100-canister, 1st transfer case of SB4 for certain frits. Five frits were tested in closed-crucible studies--Frits 320, 418, 447, 448, and 449. Tests with Frit 418 showed that SO{sub 4}{sup =} was apparent on the glass surface of tests at 40% WL and 0.6 wt% SO{sub 4}{sup =}. No salt layer formation was evident in any test (30% or 40% WL) with Frits 320, 447, 448, or 449 until SO{sub 4}{sup =} concentrations of 0.8 wt% were targeted. The crucible tests of this study and model predictions (from Jantzen and Smith, 2004) indicated that the SO{sub 4}{sup =} solubility limit for SB4 with those four frits would be similar. However, even with the additions of CaO and V2O5, the solubility of SO{sub 4}{sup =} was not greatly enhanced by Frits 447, 448, and 449 over Frit 320 for the 1100-canister, 1st transfer case. The following recommendation is made regarding the SO{sub 4}{sup =} solubility limit for SB4 in the DWPF: Reinvestigate the solubility of SO{sub 4}{sup =} for SB4 once the final blending and/or washing strategies for SB4 are determined--based on the decisions for the inclusion of Tank 4 and the exact volume and composition of the Np stream--in order to determine if the current SO{sub 4}{sup =} solubility limit (0.6 wt% SO{sub 4}{sup =}) in the DWPF needs to be increased for the processing of SB4.

Download or read book Verification of the Defense Waste Processing Facility s DWPF Process Digestion Method for the Sludge Batch 7A Qualification Sample written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) performs confirmation of the applicability of the digestion method to be used by the DWPF lab for elemental analysis of Sludge Receipt and Adjustment Tank (SRAT) receipt samples and SRAT product process control samples. DWPF SRAT samples are typically dissolved using a room temperature HF-HNO3 acid dissolution (i.e., DWPF Cold Chem Method, see DWPF Procedure SW4-15.201) and then analyzed by inductively coupled plasma - atomic emission spectroscopy (ICP-AES). This report contains the results and comparison of data generated from performing the Aqua Regia (AR), Sodium peroxide/Hydroxide Fusion (PF) and DWPF Cold Chem (CC) method digestions of Sludge Batch 7a (SB7a) SRAT Receipt and SB7a SRAT Product samples. The SB7a SRAT Receipt and SB7a SRAT Product samples were prepared in the SRNL Shielded Cells, and the SRAT Receipt material is representative of the sludge that constituates the SB7a Batch or qualification composition. This is the sludge in Tank 51 that is to be transferred into Tank 40, which will contain the heel of Sludge Batch 6 (SB6), to form the Sb7a Blend composition.

Download or read book SUMMARY REPORT FOR THE ANALYSIS OF THE SLUDGE BATCH 7A MACROBATCH 8 DWPF POUR STREAM GLASS SAMPLE FOR CANISTER S03619 written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In order to comply with the Waste Acceptance Specifications in Sludge Batch 7a (Macrobatch 8), Savannah River National Laboratory personnel characterized the Defense Waste Processing Facility (DWPF) pour stream glass sample collected while filling canister S03619. This report summarizes the results of the compositional analysis for reportable oxides and radionuclides, and the normalized Product Consistency Test (PCT) results. The PCT responses indicate that the DWPF produced glass that is significantly more durable than the Environmental Assessment glass. Results and further details are documented in 'Analysis of DWPF Sludge Batch 7a (Macrobatch 8) Pour Stream Samples, ' SRNL-STI-2012-00017.

Download or read book Verification of the Defense Waste Processing Facility s DWPF Process Digestion Method for the Sludge Batch 7B Blend Sample written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis Of DWPF Sludge Batch 7a Macrobatch 8 Pour Stream Samples written by and published by . This book was released on 2012 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Defense Waste Processing Facility (DWPF) began processing Sludge Batch 7a (SB7a), also referred to as Macrobatch 8 (MB8), in June 2011. SB7a is a blend of the heel of Tank 40 from Sludge Batch 6 (SB6) and the SB7a material that was transferred to Tank 40 from Tank 51. SB7a was processed using Frit 418. During processing of each sludge batch, the DWPF is required to take at least one glass sample to meet the objectives of the Glass Product Control Program (GPCP), which is governed by the DWPF Waste Compliance Plan, and to complete the necessary Production Records so that the final glass product may be disposed of at a Federal Repository. Three pour stream glass samples and two Melter Feed Tank (MFT) slurry samples were collected while processing SB7a. These additional samples were taken during SB7a to understand the impact of antifoam and the melter bubblers on glass redox chemistry. The samples were transferred to the Savannah River National Laboratory (SRNL) where they were analyzed.

Download or read book SLUDGE BATCH 7 SB7 WASHING DEMONSTRATION TO DETERMINE SULFATE written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: To support Sludge Batch 7 (SB7) washing, a demonstration of the proposed Tank Farm washing operation was performed utilizing a real-waste test slurry generated from Tank 4, 7, and 12 samples. The purpose of the demonstration was twofold: (1) to determine the settling time requirements and washing strategy needed to bring the SB7 slurry to the desired endpoint; and (2) to determine the impact of washing on the chemical and physical characteristics of the sludge, particularly those of sulfur content, oxalate content, and rheology. Seven wash cycles were conducted over a four month period to reduce the supernatant sodium concentration to approximately one molar. The long washing duration was due to the slow settling of the sludge and the limited compaction. Approximately 90% of the sulfur was removed through washing, and the vast majority of the sulfur was determined to be soluble from the start. In contrast, only about half of the oxalate was removed through washing, as most of the oxalate was initially insoluble and did not partition to the liquid phase until the latter washes. The final sulfur concentration was 0.45 wt% of the total solids, and the final oxalate concentration was 9,900 mg/kg slurry. More oxalate could have been removed through additional washing, although the washing would have reduced the supernatant sodium concentration. The yield stress of the final washed sludge (35 Pa) was an order of magnitude higher than that of the unwashed sludge ((almost equal to)4 Pa) and was deemed potentially problematic. The high yield stress was related to the significant increase in insoluble solids that occurred ((almost equal to)8 wt% to (almost equal to)18 wt%) as soluble solids and water were removed from the slurry. Reduction of the insoluble solids concentration to (almost equal to)14 wt% was needed to reduce the yield stress to an acceptable level. However, depending on the manner that the insoluble solids adjustment was performed, the final sodium concentration and extent of oxalate removal would be prone to change. As such, the strategy for completing the final wash cycle is integral to maintaining the proper balance of chemical and physical requirements.

Download or read book Strategy and Methodology for Radioactive Waste Characterization written by International Atomic Energy Agency and published by IAEA. This book was released on 2007 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade significant progress has been achieved in the development of waste characterization and control procedures and equipment as a direct response to ever-increasing requirements for quality and reliability of information on waste characteristics. Failure in control procedures at any step can have important, adverse consequences and may result in producing waste packages which are not compliant with the waste acceptance criteria for disposal, thereby adversely impacting the repository. The information and guidance included in this publication corresponds to recent achievements and reflects the optimum approaches, thereby reducing the potential for error and enhancing the quality of the end product. -- Publisher's description.

Download or read book Design and Operation of High Level Waste Vitrification and Storage Facilities written by International Atomic Energy Agency and published by . This book was released on 1992 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report gives an up to date review of high level waste vitrification and storage facilities currently in an advanced stage of implementation.

Download or read book Radioactive Waste Forms for the Future written by Werner Lutze and published by North Holland. This book was released on 1988 with total page 802 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents a compilation of important information on the full range of radioactive waste forms that have been developed, or at least suggested, for the incorporation of high-level nuclear waste. Many of the results were published in the ''gray literature'' of final reports of national laboratories or in various, generally less available, proceedings volumes. This is the first publication to draw information on nuclear waste forms for high-level wastes together into a single volume. Although borosilicate glass has become the standard waste form, additional research in this compound is still necessary. With improved technology (particularly processing technologies) and with a more detailed knowledge of repository conditions, glasses and second generation waste forms with improved performance properties can be developed. Sustained research programs on nuclear waste form development will yield results that can only add to public confidence and the final, safe disposal of nuclear waste. The aim of this volume is to provide a 'spring board' for these future research efforts. A detailed presentation is given on the properties and performance of non-crystalline waste forms (borosilicate glass, sintered glass, and lead-iron phosphate glass), and crystalline waste forms (Synroc, tailored ceramics, TiO 2 - ceramic matrix, glass-ceramics and FUETAP concrete). A chapter on Novel Waste Forms reviews a number of methods that warrant further development because of their potential superior performance and unique applications. The final chapter includes a tabulated comparison of important waste form properties and an extended discussion on the corrosion process and radiation damage effects for each waste form. Of particular interest is a performance assessment of nuclear waste borosilicate glass and the crystalline ceramic Synroc. This is the first detailed attempt to compare these two important waste forms on the basis of their materials properties. The discussion emphasizes the difficulties in making such a comparison and details the types of data that are required. Each chapter has been written by an expert and includes a current compilation of waste form properties with an extensive list of references. This volume will provide a stimulus for future research as well as useful reference material for scientists working in the field of nuclear waste disposal and materials science.

Download or read book Waste Forms Technology and Performance written by National Research Council and published by National Academies Press. This book was released on 2011-09-05 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Department of Energy's Office of Environmental Management (DOE-EM) is responsible for cleaning up radioactive waste and environmental contamination resulting from five decades of nuclear weapons production and testing. A major focus of this program involves the retrieval, processing, and immobilization of waste into stable, solid waste forms for disposal. Waste Forms Technology and Performance, a report requested by DOE-EM, examines requirements for waste form technology and performance in the cleanup program. The report provides information to DOE-EM to support improvements in methods for processing waste and selecting and fabricating waste forms. Waste Forms Technology and Performance places particular emphasis on processing technologies for high-level radioactive waste, DOE's most expensive and arguably most difficult cleanup challenge. The report's key messages are presented in ten findings and one recommendation.

Download or read book Green Biocomposites written by Mohammad Jawaid and published by Springer. This book was released on 2017-02-11 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces the concept, design and application of green biocomposites, with a specific focus on the current demand for green biocomposites for automotive and aerospace components. It discusses the mathematical background, innovative approaches to physical modelling, analysis and design techniques. Including numerous illustrations, tables, case studies and exercises, the text summarises current research in the field. It is a valuable reference resource for researchers, students and scientists working in the field of materials science.

Download or read book Capital Programming Guide written by United States. Office of Management and Budget and published by . This book was released on 1997 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The 1996 Baseline Environmental Management Report Report written by and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Plant Growth Promoting Microbes for Sustainable Biotic and Abiotic Stress Management written by Heba I. Mohamed and published by Springer Nature. This book was released on 2021-05-02 with total page 672 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abiotic and biotic stress factors, including drought, salinity, waterlog, temperature extremes, mineral nutrients, heavy metals, plant diseases, nematodes, viruses, and diseases, adversely affect growth as well as yield of crop plants worldwide. Plant growth-promoting microorganisms (PGPM) are receiving increasing attention from agronomists and environmentalists as candidates to develop an effective, eco-friendly, and sustainable alternative to conventional agricultural (e.g., chemical fertilizers and pesticide) and remediation (e.g., chelators-enhanced phytoremediation) methods employed to deal with climate change-induced stresses. Recent studies have shown that plant growth-promoting bacteria (PGPB), rhizobia, arbuscular mycorrhizal fungi (AMF), cyanobacteria have great potentials in the management of various agricultural and environmental problems. This book provides current research of biofertilizers and the role of microorganisms in plant health, with specific emphasis on the mitigating strategies to combat plant stresses.