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Pegg, Ian L.

Publications and source records attributed to Pegg, Ian L..

At least 19 records

Integrated DM1200 Melter Testing of HLW AZ-102 Composition Using Bubblers (Final Report)

This report documents melter and off-gas performance results obtained on the DM1200 HLW Pilot Melter during processing of simulated HLW AZ-102 feed. The principal objectives of the DM1200 melter testing were to determine the achievable glass production rates for simulated HLW AZ-102 feed; determine the effect of bubbling rate on production rate; characterize melter off-gas emissions; characterize the performance of the prototypical off-gas system components as well as their integrated performance; characterize the feed, glass product, and off-gas effluents; and to perform pre- and post test inspections of system components.

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DM1200 Tests with C-104/AY-101 HLW Simulants (Final Report)

This report documents melter and off-gas performance results obtained on the DM1200 HLW Pilot Melter during processing of simulated HLW C-104/AY-101 feed. The principal objectives of the DM1200 melter testing were to determine the achievable glass production rates for simulated HLW C-104/AY-101 feed; determine the effect of bubbling rate on production rate; characterize melter off-gas emissions; characterize the performance of the prototypical off-gas system components as well as their integrated performance; characterize the feed, glass product, and off-gas effluents; and to perform pre- and post test inspections of system components.

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Compositional Variation Tests on DuraMelter 100 with LAW Sub-Envelope C2 Feed in Support of the LAW Pilot Melter (Final Report)

One of the principal objectives of the DM100 melter tests was to demonstrate that the LAW Sub-Envelope C2 feeds with ± 15% variations in the amounts of waste simulant are suitable for large-scale tests on the LAW Pilot melter. The other principle objective for the DM100 tests was to determine the relative effects of sugar versus waste organics on glass redox state, NOx emissions, sulfur emissions, sulfur retention in the glass, secondary sulfate layer formation, and glass-melt foaming. Additional objectives included measurement of the feed rheological properties and collection of melter emissions data. Screening tests are conducted at the DM100 scale in order to identify and correct potential problems before testing at the larger scale LAW Pilot melter. Testing goals were met in that the results of the DM100 melter test resulted in selection of LAW Sub-Envelope C2 feed suitable for Pilot Melter testing.

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Integrated Off-Gas System Tests on the DM1200 Melter with RPP-WTP LAW Sub-Envelope C1 Simulants (Final Report)

The report documents melter and off-gas performance results obtained on the DM1200 during processing of LAW Sub-Envelope Cl feed. The principal objectives of the DM1200 melter testing were to demonstrate suitable processing and production rates for LAW Cl feed; characterize the glass product for elemental composition, the presence of organic compounds, and TCLP response for metals; and measure destruction and removal efficiencies (DREs) for organic compounds across the melter and off-gas treatment components. The feed was spiked with organic compounds for part of the testing duration. Data were collected for both process engineering needs and to support regulatory activities. The data needed for regulatory support were collected using EPA methods and independent data analyses and data checking were performed.

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Compositional Variation Tests on DuraMelter 100 with LAW Sub-Envelope C1 Feed (LAWC22) Glass in Support of the LAW Pilot Melter (Final Report)

The Vitreous State Laboratory at The Catholic University of America (VSL) is developing and testing glass formulations for RPP-WTP waste envelopes to provide data to meet the RPP-WTP contract requirements and to support system design activities. That work is based upon small-scale batch melts (“crucible melts”) using waste envelope simulants. Selected formulations have also been tested in small-scale continuously-fed joule-heated melters (DM10 and DM100 systems) and, ultimately, in the LAW Pilot Melter. Such melter tests provide information on key process factors such as feed processing behavior, dynamic effects during processing, sulfate incorporation, processing rates, off-gas amounts and compositions, foaming control, etc., that cannot be reliably obtained from crucible melts. This sequential scale-up approach in the vitrification testing program ensures that maximum benefit is obtained from the more costly pilot-scale tests and that the most effective use is made of that resource. The principal objective of the work described in this report was to collect the necessary small-scale melter test data with a LAW Sub-Envelope C1 waste simulant in order to support the next series of tests with the same melter feed on the LAW Pilot Melter. This work was conducted under a corresponding Test Specification and Test Plan.

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Noble Metals Testing on the DM1200 Pilot Melter System with AZ-101 HLW Simulants, VSL-03R3740-2, Rev. 0

This report documents the results obtained with respect to the behavior of noble metals in tests on the DM1200 HLW Pilot Melter during processing of simulated HLW AZ-101 feed. The principal objective of these tests was to collect data to determine the extent of retention of noble metals in the melter since that is an important uncertainty in determining the expected life of the WTP HLW melter. The present results constitute one part of an integrated testing strategy that has been developed to address this risk.

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Regulatory Testing of WTP HL W Glasses for Compliance with Delisting Requirements, VSL-03R3780-1, Rev. 1

(Part of the data collected for this work and discussed in this report was subject to data quality and bias issues. All the affected tests have subsequently been repeated, as directed by the Waste Treatment Plant Project, and new statistical analyses have been performed on the revised data set. A subsequently-issued report supercedes this report and describes the revised data, together with the revised composition-property models (Kot et al. 2004). The reader should refer to the new report for discussion of the revised data set and composition-property (TCLP cadmium release) models. None of the data for the spike glasses, designed for Case 1 and Case 2 COPCs testing, were affected by this issue.)

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Off-line Tests of the DM1200 Thermal Catalytic Oxidation (TCO) Unit (Final Report)

The River Protection Project-Waste Treatment Plant (RPP-WTP) Low-Activity Waste (LAW) and High-Level Waste (HLW) feed streams are listed for a variety of hazardous organic compounds. The permitting basis for the WTP systems may necessitate the demonstration of minimum Destruction/Removal Efficiencies (DREs) of such species from any released emissions of up to 99.99%. Results from a previous study on the fate of hazardous organics in the melter itself indicated, not only that DREs for selected test compounds approached 99.99% only at extreme melter conditions, but also that organic compounds not originally present in the feed were actually produced in the melter, In order to ensure that the required DREs for hazardous organics are met, Thermal Catalytic Oxidation (TCO) units were therefore added to both the HLW and LAW off-gas treatment systems, The extent to which these species can be destroyed or removed in the TCO units is therefore an important issue in the design and permitting of the LAW and HLW off-gas treatment systems. A further consideration is that it would be desirable, if possible, to be able to achieve all of the required DRE across the TCO alone. If that is not the case, the DRE would be distributed across several unit operations, which may then become subject to additional operational constraints that may reduce process flexibility. Compliance with the DRE requirements on the basis of the TCO unit alone is also an approach that lends itself to periodic confirmation during operations, since the TCO is located at the back-end of the off-gas treatment system where radioactivity levels are lowest.

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Corrosion Testing of Bubbler Materials for LAW Vitrification (Rev. 0)

This work involved crucible-scale corrosion tests using coupons of selected materials in the baseline glass formulations for the seven LAW Sub-Envelopes. The tests were performed with Inconel 690 and MA 758; per the Test Plan, selected tests were also performed with a proprietary high temperature alloy supplied by SRTC. Coupons of these materials were tested for their corrosion resistance to LAW baseline glasses in two test series: the first series was with a baseline glass only, the second series was with a baseline glass and an added salt layer.

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Regulatory Spike Testing of RPP-WTP LAW and HLW Glasses for Compliance with Land Disposal Restrictions, VSL-03R3760-1, Rev. 1

The United States Department of Energy’s (DOE’s) Hanford site is the current location of storage of about 50 million gallons of mixed waste. This waste is stored in underground tanks at the Hanford site and is both a listed and characteristic waste, as defined in 40 CFR Part 261, and a dangerous waste according to Chapter 173-303 of the Washington Administrative Code (WAC). The waste is also subject to the Land Disposal Restrictions (LDR) (40 CFR Part 268 and WAC 173-303-140). The River Protection Project - Waste Treatment Plant (RPP-WTP) will provide DOE with a means for treating this waste by vitrification (for subsequent disposal). The tank waste will be partitioned into low and high activity fractions, which will then be vitrified respectively into Immobilized Low Activity Waste (ILAW) and Immobilized High Level Waste (IHLW) products. The ILAW product will be disposed of in an engineered facility on the Hanford site while the IHLW product will be directed to the national deep geological disposal facility for high level nuclear waste. The ILAW and IHLW products must meet a variety of requirements with respect to protection of the environment.

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Integrated Off-Gas System Tests on the DM1200 Melter with RPP-WTP LAW Sub-Envelope Bl Simulants, VSL-03R3851-1, Rev. 0 (Oct 2003)

The report documents melter and off-gas performance results obtained on the DM1200 melter during processing of LAW Sub-Envelope B1 feed. The principal objectives of the DM1200 melter testing were to demonstrate suitable processing and production rates for LAW B1 feed; characterize the glass product for elemental composition; measure elemental emission rates and decontamination factors (DFs) across the melter and off-gas treatment components; and provide additional data on the performance of the thermal catalytic oxidation and selective catalytic reduction (TCO/SCR) unit efficiency in treating organic emissions. The feed was spiked with organic compounds for part of the testing duration. All data were collected for use in engineering and system design purposes. No sampling and analysis to collect environmental data was performed during these tests.

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Compositional Variation Tests on DuraMelter 100 with LAW Sub-Envelope A1 Feed (LAWA44 Glass) in Support of the LAW Pilot Melter, VSL-02R62N0-4, Rev. 0 (Nov 2002)

The two tests described in this report utilized blended feed (glass formers plus waste simulant) prepared by Optima Chemicals according to VSL specifications generating about 1. 7 metric tons of glass. Sugar was added (at VSL) to the nominal feed at a "sugar ratio" of 0.5 for each of the two variation tests1; however, since the sugar addition is assumed to be "blind" to the variations, the actual sugar ratios were 0.57 and 0.44. The DMl00-WV melter was used in order to provide a direct comparison with the LAW tests previously conducted on the same melter. Two 100-hour melter tests were conducted: one with a 15% deficiency in simulant and one with 15% excess in simulant. Key operating parameters including cold cap coverage, feed rate, and glass pool temperature were held constant to investigate the effects of the glass compositional changes on processing characteristics (including salt formation) and the product glass. The bubbling rate was adjusted to provide the desired glass production rate with a near complete cold cap (90-100% of melt surface covered with feed). Quantitative measurements of glass production rates, melter operating conditions (temperatures, pressures, power, flows, etc.), and off-gas characteristics (NOx, SO 2, CO, particulate load and composition, and acid gases) were made for each test.

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Compositional Variation Tests on DuraMelter 100 with LAW Sub-Envelope B1 Feed in Support of the LAW Pilot Melter, VSL-02R62N0-5, Rev. 0 (May 2003)

The principal objective of the DM100 tests was to demonstrate the robustness of the vitrification process with respect to feed and glass compositional changes resulting from variations in the simulant-to-additive ratio. The DM100-WV unit was selected for these tests; this melter was used for all of the Part B 1 tests on LAW Envelopes A, B, and C sulfate incorporation that were used to support the subsequent tests on the Pilot Melter as well as for the more recent LAW Sub-Envelope Al, A2, A3 and Cl tests. The same melter was selected for the present tests in order to maintain comparisons between the data sets. In addition, the somewhat smaller glass volume for the same melt surface area as compared to the DM100-BL melter means that more glass turnovers are achieved for a given test duration. The DM100 tests used nominal feed and feed with a 15% surplus in waste simulant. Previous Pilot Melter tests on Envelope A with 10% variations (but with sulfate removal) showed significant impacts on glass production rates that were ultimately corrected by adjustments in the sugar additions. Consequently, robustness with respect to throughput as well as sulfate tolerance are important motivations for these tests.

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Regulatory Testing of RPP-WTP HLW Glasses to Support Delisting Compliance, VSL-04R4780-1, Rev. 0 (Sep 2004)

The primary goal of the testing described in this report was to collect data to demonstrate compliance of the immobilized high-level waste (IHLW) glasses with delisting requirements. The collected data will be used to support a petition to delist the IHLW glasses destined for the national disposal facility. The Delisting Data Quality Objectives (DQO) (Cook and Blumenkranz 2003) identified a list of (16) inorganic constituents of potential concern (COPCs) and their associated limits for delisting. These COPCs can be divided into three groups, Cases 1, 2, and 3, based on their Toxicity Characteristic Leaching Procedure (TCLP) responses versus their respective delisting limits. To briefly summarize, Case 1 COPCs are those that, when loaded at their highest expected concentration in Waste Treatment Plant (WTP) glasses, are not expected to leach at their respective delisting limits when the glasses are exposed to the TCLP. Case 2 COPCs may reach the delisting limits in TCLP leachates of WTP glasses if loaded to concentrations near their maximum expected concentrations in glass. Finally, Case 3 COPCs are components that are likely to be present in concentrations sufficient to exceed their respective delisting limits in TCLP leachates of some possible glasses. The test objective was to show that, for (i) the expected range of inorganic contents in the waste feed to the Hanford WTP high level waste (HLW) vitrification facility, (ii) the expected range of glass product compositions, and (iii) the Case 1 and Case 2 COPCs identified by the DQO, the IHLW glasses meet all the relevant requirements for delisting. For Case 3 COPCs (i.e., Cd), the testing was to demonstrate the relationship between glass composition and TCLP cadmium (Cd) release, and then employ the results to develop TCLP-composition response models. During WTP operations, TCLP-composition models can be used to predict, within the required statistical uncertainties, TCLP responses of IHLW production glasses that are within the compositional region used to develop the model.

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LAW Glass Formulation to Support Melter Runs with Simulants

The major objective of this work was to prepare and characterize glass formulations in order to develop and select formulations that are compliant with contractual and processing requirements to support melter tests with each of the LAW Sub-Envelopes. Glasses that cover composition ranges of interest were prepared and characterized to ensure that selected glass compositions can tolerate expected composition variations resulting from process errors without adversely affecting processing characteristics or product quality. Glass compositions that are expected to result during transitions from one waste stream to another were also prepared and characterized. Other objectives of the work included preparation and characterization of glasses with respect to the properties of interest, optimization of sulfate loading in the glasses, evaluation of ability to achieve waste loading limits, testing to demonstrate compatibility of glass melts with melter materials of construction, and identification of glass formulation issues with respect to contract specifications and processing requirements.

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Low Activity Waste Tuning Feed Material Testing VSL-18R4350-1 (Final Report)

High level waste (HLW) from the Hanford tank farms will be retrieved and transferred to the Hanford Tank Waste Treatment and Immobilization Plant (WTP). The waste will be pretreated to separate the soluble chemical salts (mostly sodium nitrate/nitrite and sodium hydroxide) from the bulk of the radioactive materials. This decontaminated salt solution is the low activity waste (LAW) stream which constitutes most of the total waste volume. The remaining HLW contains most of the radioactive materials but a fraction of the volume. Each of these waste streams is directed to an independent processing facility where the waste is mixed with glass forming chemicals (mostly silica and borax or boric acid) and fed into the melters for stabilization by conversion into glass. The molten glass is poured into stainless steel containers to produce packages for disposal: local shallow burial for the LAW containers and a future geologic repository for the HLW containers. The LAW facility melters produce significant quantities of NOx-laden off-gas that require abatement in accordance with 10 CFR 830 and air emission requirements. The NOx emissions also pose a safety risk. The LAW facility commissioning sequence requires that the melters be operated and process control loops tuned prior to introducing waste or waste feed materials that produce NOx. Therefore, a temporary or permanent system architecture is needed that provides a feed supply to the melters for the purpose of melter testing and off-gas tuning that does not result in the production of significantly hazardous off-gas products.

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Iodine Removal in the DFLAW Flow-Sheet

In support of the WTP project, off-gas system and regulatory testing has been conducted previously on the DM1200 pilot melter equipped with a prototypical off-gas system installed at The Catholic University of America’s Vitreous State Laboratory (VSL). During the regulatory tests, an AC-S test bed filled with Kombisorb BAT 37 was included in the prototypical off-gas system and evaluated for response to HLW and LAW exhaust streams. Offline testing and small-scale testing of that media were also conducted. Testing demonstrated that a temperature rise occurred in the activated carbon media when water vapor was first introduced to virgin Kombisorb BAT 37, in response to high nitrogen oxide concentrations, and in response to the presence of organic compounds. Conditioning of the test bed by gradually increasing the NOx concentration prior to the introduction of organics was found to be an important operational strategy for preventing larger temperature excursions. However, no mercury was present in the exhaust stream during DM1200 testing and therefore comparable test data for mercury removal efficiency or temperature response of the carbon media in the presence of mercury were not collected in the DM1200 tests. In view of the need for data on mercury removal performance, BNI contracted with Atkins and the VSL to install and operate a suitable test system at VSL to collect the required data. That testing was designed to assess the performance of Kombisorb BAT-37 and the guard bed material, Sofnolime RG, for simulated melter exhaust streams that contain the highest concentrations of mercury, nitrogen oxides, acid gases, and organic compounds expected in WTP LAW melter exhaust. During shakedown testing with the new system, however, it became evident that a number of issues with Sofnolime RG as the guard bed material would render it unsuitable for this application. BNI subsequently determined that the guard bed was redundant for removal of acid gases since they could be adequately removed by the SBS and WESP. However, since the guard bed material was also credited with significant iodine removal , there was a need for a replacement material that would adequately perform that role. BNI identified several candidate media but performance data in gas compositions that are representative of the WTP LAW off-gas were not available. Accordingly, there was a need to test and evaluate the performance of these candidate media prior to performing the originally-planned tests. To that end, small scale tests were conducted to assess the performance of various adsorbents in simulated melter exhaust streams that contain mercury, iodine, nitrogen oxides, acid gases, and acetonitrile, which are expected to be present in WTP LAW melter exhaust.

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FY2021 Rotating Bed Reactor for Iodine Removal from ETF Feed to Support DFLAW Start-Up

In FY20, Washington River Protection Solutions, LLC (WRPS) began a program of work to evaluate potential technologies for removal of iodine from the ETF feed. Work at the Pacific Northwest National Laboratory (PNNL) focused on ion exchange media and conventional column based deployment while Atkins and VSL focused on ion exchange media in a Rotating Bed Reactor (RBR) system. In the RBR system, the ion exchange media is loaded into a packed bed, which is rotated in the liquid to be treated. The work described in this report builds on the results from FY20 work, in particular, with regard to improving iodate removal, extending the data set to support process modeling, further comparison of RBR versus column performance, and RBR scale-up testing.

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