EBookClubs

Read Books & Download eBooks Full Online

EBookClubs

Read Books & Download eBooks Full Online

Book REAL WASTE TESTING OF SLUDGE BATCH 5 MELTER FEED RHEOLOGY

Download or read book REAL WASTE TESTING OF SLUDGE BATCH 5 MELTER FEED RHEOLOGY written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Clogging of the melter feed loop at the Defense Waste Processing Facility (DWPF) has reduced the throughput of Sludge Batch 5 (SB5) processing. After completing a data review, DWPF attributed the clogging to the rheological properties of the Slurry Mix Evaporator (SME) project. The yield stress of the SB5 melter feed material was expected to be high, based on the relatively high pH of the SME product and the rheological results of a previous Chemical Process Cell (CPC) demonstration performed at the Savannah River National Laboratory (SRNL).

Book Sludge Mass Reduction

Download or read book Sludge Mass Reduction written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Savannah River National Laboratory (SRNL) was tasked to provide an assessment of the downstream impacts to the Defense Waste Processing Facility (DWPF) of decisions regarding the implementation of Al-dissolution to support sludge mass reduction and processing. Based on future sludge batch compositional projections from the Liquid Waste Organization's (LWO) sludge batch plan, assessments have been made with respect to the ability to maintain comparable projected operating windows for sludges with and without Al-dissolution. As part of that previous assessment, candidate frits were identified to provide insight into melt rate for average sludge batches representing with and without Al-dissolution flowsheets. Initial melt rate studies using the melt rate furnace (MRF) were performed using five frits each for Cluster 2 and Cluster 4 compositions representing average without and with Al-dissolution. It was determined, however, that the REDOX endpoint (Fe{sup 2+}/[Sigma]Fe for the glass) for Clusters 2 and 4 resulted in an overly oxidized feed which negatively affected the initial melt rate tests. After the sludge was adjusted to a more reduced state, additional testing was performed with frits that contained both high and low concentrations of sodium and boron oxides. These frits were selected strictly based on the ability to ascertain compositional trends in melt rate and did not necessarily apply to any acceptability criteria for DWPF processing. The melt rate data are in general agreement with historical trends observed at SRNL and during processing of SB3 (Sludge Batch 3)and SB4 in DWPF. When MAR acceptability criteria were applied, Frit 510 was seen to have the highest melt rate at 0.67 in/hr for Cluster 2 (without Al-dissolution), which is compositionally similar to SB4. For Cluster 4 (with Al-dissolution), which is compositionally similar to SB3, Frit 418 had the highest melt rate at 0.63 in/hr. Based on this data, there appears to be a slight advantage of the Frit 510 based system without Al-dissolution relative to the Frit 418 based system with Al-dissolution. Though the without aluminum dissolution scenario suggests a slightly higher melt rate with frit 510, several points must be taken into consideration: (1) The MRF does not have the ability to assess liquid feeds and, thus, rheology impacts. Instead, the MRF is a 'static' test bed in which a mass of dried melter feed (SRAT product plus frit) is placed in an 'isothermal' furnace for a period of time to assess melt rate. These conditions, although historically effective in terms of identifying candidate frits for specific sludge batches and mapping out melt rate versus waste loading trends, do not allow for assessments of the potential impact of feed rheology on melt rate. That is, if the rheological properties of the slurried melter feed resulted in the mounding of the feed in the melter (i.e., the melter feed was thick and did not flow across the cold cap), melt rate and/or melter operations (i.e., surges) could be negatively impacted. This could affect one or both flowsheets. (2) Waste throughput factors were not determined for Frit 510 and Frit 418 over multiple waste loadings. In order to provide insight into the mission life versus canister count question, one needs to define the maximum waste throughput for both flowsheets. Due to funding limitations, the melt rate testing only evaluated melt rate at a fixed waste loading. (3) DWPF will be processing SB5 through their facility in mid-November 2008. Insight into the over arching questions of melt rate, waste throughput, and mission life can be obtained directly from the facility. It is recommended that processing of SB5 through the facility be monitored closely and that data be used as input into the decision making process on whether to implement Al-dissolution for future sludge batches.

Book MELT RATE FURNACE TESTING FOR SLUDGE BATCH 5 FRIT OPTIMIZATION

Download or read book MELT RATE FURNACE TESTING FOR SLUDGE BATCH 5 FRIT OPTIMIZATION written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Savannah River National Laboratory (SRNL) was requested to provide the Defense Waste Processing Facility (DWPF) with a frit composition for Sludge Batch 5 (SB5) to optimize processing. A series of experiments were designed for testing in the Melt Rate Furnace (MRF). This dry fed tool can be used to quickly determine relative melt rates for a large number of candidate frit compositions and lead to a selection for further testing. Simulated Sludge Receipt and Adjustment Tank (SRAT) product was made according to the most recent SB5 sludge projections and a series of tests were conducted with frits that covered a range of boron and alkali ratios. Several frits with relatively large projected operating windows indicated melt rates that would not severely impact production. As seen with previous MRF testing, increasing the boron concentration had positive impacts on melt rate on the SB5 system. However, there appears to be maximum values for both boron and sodium above which the there is a negative effect on melt rate. Based on these data and compositional trends, Frit 418 and a specially designed frit (Frit 550) have been selected for additional melt rate testing. Frit 418 and Frit 550 will be run in the Slurry Fed Melt Rate Furnace (SMRF), which is capable of distinguishing rheological properties not detected by the MRF. Frit 418 will be used initially for SB5 processing in DWPF (given its robustness to compositional uncertainty). The Frit 418-SB5 system will provide a baseline from which potential melt rate advantages of Frit 550 can be gauged. The data from SMRF testing will be used to determine whether Frit 550 should be recommended for implementation in DWPF.

Book Rheological and Elemental Analyses of Simulant SB5 Slurry Mix Evaporator Melter Feed Tank Slurries

Download or read book Rheological and Elemental Analyses of Simulant SB5 Slurry Mix Evaporator Melter Feed Tank Slurries written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Defense Waste Processing Facility (DWPF) will complete Sludge Batch 5 (SB5) processing in fiscal year 2010. DWPF has experienced multiple feed stoppages for the SB5 Melter Feed Tank (MFT) due to clogs. Melter throughput is decreased not only due to the feed stoppage, but also because dilution of the feed by addition of prime water (about 60 gallons), which is required to restart the MFT pump. SB5 conditions are different from previous batches in one respect: pH of the Slurry Mix Evaporator (SME) product (9 for SB5 vs. 7 for SB4). Since a higher pH could cause gel formation, due in part to greater leaching from the glass frit into the supernate, SRNL studies were undertaken to check this hypothesis. The clogging issue is addressed by this simulant work, requested via a technical task request from DWPF. The experiments were conducted at Aiken County Technology Laboratory (ACTL) wherein a non-radioactive simulant consisting of SB5 Sludge Receipt and Adjustment Tank (SRAT) product simulant and frit was subjected to a 30 hour SME cycle at two different pH levels, 7.5 and 10; the boiling was completed over a period of six days. Rheology and supernate elemental composition measurements were conducted. The caustic run exhibited foaming once, after 30 minutes of boiling. It was expected that caustic boiling would exhibit a greater leaching rate, which could cause formation of sodium aluminosilicate and would allow gel formation to increase the thickness of the simulant. Xray Diffraction (XRD) measurements of the simulant did not detect crystalline sodium aluminosilicate, a possible gel formation species. Instead, it was observed that caustic conditions, but not necessarily boiling time, induced greater thickness, but lowered the leach rate. Leaching consists of the formation of metal hydroxides from the oxides, formation of boric acid from the boron oxide, and dissolution of SiO2, the major frit component. It is likely that the observed precipitation of Mg(OH)2 and Mn(OH)2 caused the increase in yield stress. The low pH run exhibited as much as an order of magnitude greater B and Li (frit components) leachate concentrations in the supernate. At high pH a decrease of B leaching was found and this was attributed to adsorption onto Mg(OH)2. A second leaching experiment was performed without any sludge to deconvolute the leach rate behavior of Frit 418 from those of the SB5 sludge-Frit 418 system. At high pH, the sludgeless system demonstrated very fast leaching of all the frit components, primarily due to fast dissolution of the main component, silica, by hydroxide anion; various semiconductor studies have established this reactivity. Overall, the frit-water system exhibited greater leaching from a factor two to almost three orders of magnitude (varying by conditions and species). The slower leaching of the sludge system is possibly due to a greater ionic strength or smaller driving force. Another possible reason is a physical effect, coating of the frit particles with sludge; this would increase the mass transfer resistance to leaching. Based on this study, the cause of clogs in the melter feed loop is still unknown. A possible explanation is that the SME product, like the simulant, is too thin and could contribute to a loss of two-phase flow which could cause plugging of a restricted and poorly mixed zone like the melter feed loop. This is feasible since a previous study of a slurry showed an increase in resistance to flow at lower flow rates. Testing with a radioactive SME sample is underway and should help understand this potential mechanism.

Book SLUDGE BATCH 4 BASELINE MELT RATE FURNACE AND SLURRY FED MELT RATE FURNACE TESTS WITH FRITS 418 AND 510  U

Download or read book SLUDGE BATCH 4 BASELINE MELT RATE FURNACE AND SLURRY FED MELT RATE FURNACE TESTS WITH FRITS 418 AND 510 U written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Several Slurry-Fed Melt Rate Furnace (SMRF) tests with earlier projections of the Sludge Batch 4 (SB4) composition have been performed. 1,2 The first SB4 SMRF test used Frits 418 and 320, however it was found after the test that the REDuction/OXidation (REDOX) correlation at that time did not have the proper oxidation state for manganese. Because the manganese level in the SB4 sludge was higher than previous sludge batches tested, the impact of the higher manganese oxidation state was greater. The glasses were highly oxidized and very foamy, and therefore the results were inconclusive. After resolving this REDOX issue, Frits 418, 425, and 503 were tested in the SMRF with the updated baseline SB4 projection. Based on dry-fed Melt Rate Furnace (MRF) tests and the above mentioned SMRF tests, two previous frit recommendations were made by the Savannah River National Laboratory (SRNL) for processing of SB4 in the Defense Waste Processing Facility (DWPF). The first was Frit 503 based on the June 2006 composition projections. 3 The recommendation was changed to Frit 418 as a result of the October 2006 composition projections (after the Tank 40 decant was implemented as part of the preparation plan). However, the start of SB4 processing was delayed due to the control room consolidation outage and the repair of the valve box in the Tank 51 to Tank 40 transfer line. These delays resulted in changes to the projected SB4 composition. Due to the slight change in composition and based on preliminary dry-fed MRF testing, SRNL believed that Frit 510 would increase throughput in processing SB4 in DWPF. Frit 418, which was used in processing Sludge Batch 3 (SB3), was a viable candidate and available in DWPF. Therefore, it was used during the initial SB4 processing. Due to the potential for higher melt rates with Frit 510, SMRF tests with the latest SB4 composition (1298 canisters) and Frits 510 and 418 were performed at a targeted waste loading (WL) of 35%. The '1298 canisters' describes the number of equivalent canisters that would be produced from the beginning of the current contract period before SB3 is blended with SB4. The melt rate for the SMRF SB4/Frit 510 test was 14.6 grams/minute. Due to cold cap mounding problems with the SMRF SB4/Frit 418 feed at 50 weight % solids that prevented a melt rate determination, this feed was diluted to 45 weight % solids. The melt rate for this diluted feed was 8.9 grams/minute. A correction factor of 1.2 for estimating the melt rate at 50 weight % solids from 45 weight % solids test results (based on previous SMRF testing5) was then used to estimate a melt rate of 10.7 grams/minute for SB4/Frit 418 at 50 weight % solids. Therefore, the use of Frit 510 versus Frit 418 with SB4 resulted in a higher melt rate (14.6 versus an estimated 10.7 grams/minute). For reference, a previous SMRF test with SB3/Frit 418 feed at 35% waste loading and 50 weight % solids resulted in a melt rate of 14.1 grams/minute. Therefore, depending on the actual feed rheology, the use of Frit 510 with SB4 could result in similar melt rates as experienced with SB3/Frit 418 feed in the DWPF.

Book MELT RATE TESTING FOR SLUDGE BATCH 6

Download or read book MELT RATE TESTING FOR SLUDGE BATCH 6 written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Savannah River National Laboratory (SRNL) was requested to provide Savannah River Remediation (SRR) with a recommended frit composition for Sludge Batch 6 (SB6) to optimize processing at the Defense Waste Processing Facility (DWPF). This report discusses the results of a series of melt rate experiments that were completed in support of the frit recommendation and the preparation of the feed used in the testing. The objective of the work was to identify the impact of individual frit component concentrations on melt rate for both SB6 and for DWPF sludge batches in general. The dry fed, Melt Rate Furnace (MRF) was used to compare the relative melt rate performance of several candidate frit compositions. Sludge composition projection changes and variation led to the fabrication and testing of several new frits along with Frit 418, which is currently utilized at the DWPF for Sludge Batch 5 (SB5) processing. The melt rate testing results show that changes in the frit composition, such as increases in B2O3 or Li2O concentrations, can provide a faster melt rate for SB6 relative to Frit 418. However, the composition of SB6 as currently projected (February 2010 blended with a 40 inch heel of SB5) does not allow for significant changes in frit composition relative to Frit 418 without compromising the projected operating windows. Only one of the new frits tested, Frit IS7, remains viable for SB6 processing based on the current composition projections. The melt rate results also demonstrated that a low Na2O concentration frit (particularly Frit IS7) can provide reasonable melt rates if the concentrations of Li2O or B2O3 in the frit are increased. The measured melt rate for Frit IS7 with the simulated SB6 feed was about 15% faster than that for Frit 418. The projected operating windows for Frits 418 and IS7 are very similar with the current SB6 projections. However, waste loadings with Frit IS7 are limited by low viscosity predictions, while waste loadings with Frit 418 are limited by predictions of nepheline crystallization. It is recommended that SRNL reevaluate the final SB6 composition once washing and blending are complete to determine whether a change in frit composition could provide improved operating windows, improved sulfate solubility, and/or increased waste throughput.

Book Sludge Batch 5 Slurry Fed Melt Rate Furnace Test with Frits 418 and 550

Download or read book Sludge Batch 5 Slurry Fed Melt Rate Furnace Test with Frits 418 and 550 written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Based on Melt Rate Furnace (MRF) testing for the Sludge Batch 5 (SB5) projected composition and assessments of the potential frits with reasonable operating windows, the Savannah River National Laboratory (SRNL) recommended Slurry Fed Melt Rate Furnace (SMRF) testing with Frits 418 and 550. DWPF is currently using Frit 418 with SB5 based on SRNL's recommendation due to its ability to accommodate significant sodium variation in the sludge composition. However, experience with high boron containing frits in DWPF indicated a potential advantage for Frit 550 might exist. Therefore, SRNL performed SMRF testing to assess Frit 550's potential advantages. The results of SMRF testing with SB5 simulant indicate that there is no appreciable difference in melt rate between Frit 418 and Frit 550 at a targeted 34 weight % waste loading. Both batches exhibited comparable behavior when delivered through the feed tube by the peristaltic pump. Limited observation of the cold cap during both runs showed no indication of major cold cap mounding. MRF testing, performed after the SMRF runs due to time constraints, with the same two Slurry Mix Evaporator (SME) dried products led to the same conclusion. Although visual observations of the cross-sectioned MRF beakers indicated differences in the appearance of the two systems, the measured melt rates were both (almost equal to)0.6 in/hr. Therefore, SRNL does not recommend a change from Frit 418 for the initial SB5 processing in DWPF. Once the actual SB5 composition is known and revised projections of SB5 after the neptunium stream addition and any decants is provided, SRNL will perform an additional compositional window assessment with Frit 418. If requested, SRNL can also include other potential frits in this assessment should processing of SB5 with Frit 418 result in less than desirable melter throughput in DWPF. The frits would then be subjected to melt rate testing at SRNL to determine any potential advantages.

Book Radioactive Waste Management

Download or read book Radioactive Waste Management written by and published by . This book was released on 1981 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Rheological Properties of Defense Waste Slurries

Download or read book Rheological Properties of Defense Waste Slurries written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The major objective of this two-year project has been to obtain refined and reliable experimental data about the rheological properties of melter feeds. The research has involved both experimental studies and model development. Two experimental facilities have been set up to measure viscosity and pressure drop. Mathematical models have been developed as a result of experimental observation and fundamental rheological theory. The model has the capability to predict the viscosity of melter slurries in a range of experimental conditions. The final results of the investigation could be used to enhance the current design base for slurry transportation systems and improve the performance of the slurry mixing process. If successful, the cost of this waste treatment will be reduced, and disposal safety will be increased. The specific objectives for this project included: (1) the design, implementation, and validation of the experimental facility in both batch and continuous operating modes; (2) the identification and preparation of melter feed samples of both the SRS and Hanford waste slurries at multiple solids concentration levels; (3) the measurement and analysis of the melter feeds to determine the effects of the solids concentration, pH value, and other factors on the rheological properties of the slurries; (4) the correlation of the rheological properties as a function of the measured physical and chemical parameters; and (5) transmission of the experimental data and resulting correlation to the DOE site user to guide melter feed preparation and transport equipment design.

Book Rheological Properties of Defense Waste Processing Facility Melter Feeds

Download or read book Rheological Properties of Defense Waste Processing Facility Melter Feeds written by and published by . This book was released on 1998 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the present investigation, viscosity measurements have been carried out for two types of simulated Defense waste slurries, a Savannah River slurry and a Hanford slurry. The measurements were conducted in two experimental options. A rotational viscometer was used to measure viscosity under well-defined temperature and pH value operating conditions. The solids concentration used for this option was lower than 15 wt.%. Both the slurries have been investigated using this experimental option. The Savannah River slurry has also been investigated in a pipeline flow system, which measured the pressure drop as the slurry flowed through the pipe. The slurry's viscosity can be extracted from the pressure drop information. These investigations have been performed in relatively wide parameter ranges. The solids concentration of the slurry tested in the pipeline system was as high as 25 wt.%. The slurry pH in both experimental options covered a range of 4 to 13.5. The highest operating temperature was 66 C for the rotational viscometer and 55 C for the pipeline system. In FY97, the experiments for the Hanford slurry in the pipeline system will be performed.

Book Rheology of Savannah River Site Tank 51 HLW Radioactive Sludge

Download or read book Rheology of Savannah River Site Tank 51 HLW Radioactive Sludge written by and published by . This book was released on 1993 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Savannah River Site (SRS) Tank 51 HLW radioactive sludge represents a major portion of the first batch of sludge to be vitrified in the Defense Waste Processing Facility (DWPF) at SRS. The rheological properties of Tank 51 sludge will determine if the waste sludge can be pumped by the current DWPF process cell pump design and the homogeneity of melter feed slurries. The rheological properties of Tank 51 sludge and sludge/frit slurries at various solids concentrations were measured remotely in the Shielded Cells Operations (SCO) at the Savannah River Technology Center (SRTC) using a modified Haake Rotovisco viscometer system. Rheological properties of Tank 51 radioactive sludge/Frit 202 slurries increased drastically when the solids content was above 41 wt %. The yield stresses of Tank 51 sludge and sludge/frit slurries fall within the limits of the DWPF equipment design basis. The apparent viscosities also fall within the DWPF design basis for sludge consistency. All the results indicate that Tank 51 waste sludge and sludge/frit slurries are pumpable throughout the DWPF processes based on the current process cell pump design, and should produce homogeneous melter feed slurries.

Book SLUDGE BATCH 5 SIMULANT FLOWSHEET STUDIES

Download or read book SLUDGE BATCH 5 SIMULANT FLOWSHEET STUDIES written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Defense Waste Processing Facility (DWPF) will transition from Sludge Batch 4 (SB4) processing to Sludge Batch 5 (SB5) processing in early fiscal year 2009. Tests were conducted using non-radioactive simulants of the expected SB5 composition to determine the impact of varying the acid stoichiometry during the Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME) processes. The work was conducted to meet the Technical Task Request (TTR) HLW/DWPF/TTR-2007-0007, Rev. 1 and followed the guidelines of a Task Technical and Quality Assurance Plan (TT & QAP). The flowsheet studies are performed to evaluate the potential chemical processing issues, hydrogen generation rates, and process slurry rheological properties as a function of acid stoichiometry. Initial SB5 flowsheet studies were conducted to guide decisions during the sludge batch preparation process. These studies were conducted with the estimated SB5 composition at the time of the study. The composition has changed slightly since these studies were completed due to changes in the washing plan to prepare SB5 and the estimated SB4 heel mass. Nine DWPF process simulations were completed in 4-L laboratory-scale equipment using both a batch simulant (Tank 51 simulant after washing is complete) and a blend simulant (Tank 40 simulant after Tank 51 transfer is complete). Each simulant had a set of four SRAT and SME simulations at varying acid stoichiometry levels (115%, 130%, 145% and 160%). One additional run was made using blend simulant at 130% acid that included additions of the Actinide Removal Process (ARP) waste prior to acid addition and the Modular Caustic Side Solvent Extraction (CSSX) Unit (MCU) waste following SRAT dewatering. There are several parameters that are noteworthy concerning SB5 sludge: (1) This is the first batch DWPF will be processing that contains sludge that has had a significant fraction of aluminum removed through aluminum dissolution. (2) The sludge is high in mercury. (3) The sludge is high in noble metals. (4) The sludge is high in U and Pu--components that are not added in sludge simulants. Two SB5 processing issues were noted during testing. First, high hydrogen generation rates were measured during experiments with both the blend and batch simulant at high acid stoichiometry. Also, the reflux time was extended due to the high mercury concentration in both the batch and blend simulant. Adding ARP will extend processing times in DWPF. The ARP caustic boil took approximately six hours. The boiling time during the experiment with added MCU was 14 hours at the maximum DWPF steam flux rate. This is comparable to the DWPF processing time for dewatering plus reflux without MCU at a 5000 lbs/hr boil-up rate, but would require significantly more time at boiling at 2000-2500 lbs/hr boil-up rate. The addition of ARP and MCU did not cause any other processing issues, since foaming, rheology and hydrogen generation were less of an issue while processing with ARP/MCU.

Book The Impact of the Source of Alkali on Sludge Batch 3 Melt Rate  U

Download or read book The Impact of the Source of Alkali on Sludge Batch 3 Melt Rate U written by M. Smith and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Previous Savannah River National Laboratory (SRNL) melt rate tests in support of the Defense Waste Processing Facility (DWPF) have indicated that improvements in melt rate can be achieved through an increase in the total alkali of the melter feed. Higher alkali can be attained by the use of an ''underwashed'' sludge, a high alkali frit, or a combination of the two. Although the general trend between melt rate and total alkali (in particular Na{sub 2}O content) has been demonstrated, the question of ''does the source of alkali (SOA) matter?'' still exists. Therefore the purpose of this set of tests was to determine if the source of alkali (frit versus sludge) can impact melt rate. The general test concept was to transition from a Na{sub 2}O-rich frit to a Na{sub 2}O-deficient frit while compensating the Na{sub 2}O content in the sludge to maintain the same overall Na{sub 2}O content in the melter feed. Specifically, the strategy was to vary the amount of alkali in frits and in the sludge batch 3 (SB3) sludge simulant (midpoint or baseline feed was SB3/Frit 418 at 35% waste loading) so that the resultant feeds had the same final glass composition when vitrified. A set of SOA feeds using frits ranging from 0 to 16 weight % Na{sub 2}O (in 4% increments) was first tested in the Melt Rate Furnace (MRF) to determine if indeed there was an impact. The dry-fed MRF tests indicated that if the alkali is too depleted from either the sludge (16% Na{sub 2}O feed) or the frit (the 0% Na{sub 2}O feed), then melt rate was negatively impacted when compared to the baseline SB3/Frit 418 feed currently being processed at DWPF. The MRF melt rates for the 4 and 12% SOA feeds were similar to the baseline SB3/Frit 418 (8% SOA) feed. Due to this finding, a smaller subset of SOA feeds that could be processed in the DWPF (4 and 12% SOA feeds) was then tested in the Slurry-fed Melt Rate Furnace (SMRF). The results from a previous SMRF test with SB3/Frit 418 (Smith et al. 2004) were used as the SMRF melt rate of the baseline feed. The SOA SMRF test results agreed with those of the MRF tests for these two feeds as the melt rates were similar to the baseline SB3/Frit 418 feed. In other words, the source of alkali was close enough to the baseline feed as to not negatively impact melt rate. Based on these results, there appears to be an acceptable range of the source of alkali that results in the highest melt rate for a particular sludge batch. If, however, the alkali is too depleted from either the sludge or the frit, then melt rate will be lower. Although SB3 simulant sludge and Frit 418 were used for these tests, it was not the intent of these tests to determine an optimum source of alkali range for SB3. Rather, the findings of these tests should be used to help in the decision process for future sludge batch washing and/or blending strategies. The results, however, do confirm that the current processing of SB3 is being performed in the proper source of alkali range. Because all of this testing was performed on small-scale equipment with slurried, non-radioactive simulant, the exact impact of the source of alkali with SB3 in the DWPF melter could not be fully evaluated.

Book CST Melter Feed Characterization in Support of the 1999 and 2000 Thermal Fluids Lab Hydragard Testing

Download or read book CST Melter Feed Characterization in Support of the 1999 and 2000 Thermal Fluids Lab Hydragard Testing written by and published by . This book was released on 2001 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Immobilization Technology Section measured properties of the melter feed simulants used in the 1999 and 2000 Hydragard sample loop tests. These tests used simulated Sludge Batch 1B (Macrobatch 2) melter feeds. The melter feeds were characterized for wt. percent total and insoluble solids, pH, composition, particle size distribution, and rheology.

Book Initial SB4 Melt Rate Furnace Testing  U

Download or read book Initial SB4 Melt Rate Furnace Testing U written by M. Smith and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Defense Waste Processing Facility (DWPF) is presently vitrifying Sludge Batch 3 (SB3) and preparing to process Sludge Batch 4 (SB4) in late 2006 or early 2007. The final composition of SB4 has not been finalized, as various blending and/or washing strategies are still being considered. SB4 will be comprised of the contents of Tanks 5, 6, 7, 8, and 11 (which will be transferred to Tank 51) along with plutonium and neptunium solutions from F and H Canyons, and possibly material from Tank 4. Tank 4 was originally included in projections, but plans have since changed (after completion of these tests) and Tank 4 is no longer part of SB4 due to problems with sludge removal. Even though the final SB4 composition was not finalized at the time of this study, there were 20 bounding options documented that could be used for preliminary melt rate tests. At the time of these tests, the SB4 compositions described as ''SB4 1200 canister baseline'' and ''SB4 1200 canister baseline (one less washed)'' documented elsewhere were chosen for these tests. The 1200 canister describes the number of equivalent canisters that would be produced from the beginning of the current contract period before SB3 is blended with SB4. These compositions were chosen as they had the highest amount of SB4 in the blend and were therefore considered as worse case SB4 feeds with regards to melt rate. This is because SB4 has higher alumina levels of any sludge batch yet processed and alumina has a negative impact on the DWPF melt rate. This baseline sludge includes Tank 4 but does not include auxiliary waste streams such as the Actinide Removal Process (ARP) stream, which contains monosodium titanate (MST), entrained sludge, and various soluble sodium compounds as the result of filter cleaning and stream adjustment for transfer. These preliminary dry-fed Melt Rate Furnace (MRF) tests were needed to initially evaluate melt rate/waste throughput. This study addressed SB4 with Frits 418 and 320, the impact of waste loading, the impact of the higher amount of Al in SB4, the amount of sludge washing, the possible addition of the ARP stream, the possible need to use a new frit to increase sulfur solubility, and the impact of the use of low Li frits to minimize the formation of an Al-Li-silicate phase that may be an intermediate reaction phase that could possibly hinder melt rate for SB4. For the SB4 sludge tested in the MRF for this preliminary work, the melt rate for SB4 simulant was lower than SB3. The higher alumina content in SB4 is probably the reason for the lower SB4 melt rate. Because the actual SB4 composition has not yet been finalized and may be different enough from the simulant SB4 sludges tested for these tests, the actual difference in melt rate for the two sludge batches cannot be projected. Therefore, further melt rate testing, including slurry testing in the Slurry-Fed Melt Rate Furnace (SMRF) will be needed as the SB4 compositions are further refined. Tests were performed with non-radioactive, simulated SB4 material. Due to the small-scale of the test equipment and the design of the equipment, as well as the use of dry, non-radioactive simulant feed, the behavior of the actual radioactive SB4 feed in the DWPF melter cannot be fully proven.

Book OVERVIEW OF TESTING TO SUPPORT PROCESSING OF SLUDGE BATCH 4 IN THE DEFENSE WASTE PROCESSING FACILITY

Download or read book OVERVIEW OF TESTING TO SUPPORT PROCESSING OF SLUDGE BATCH 4 IN THE DEFENSE WASTE PROCESSING FACILITY written by C. Herman and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Defense Waste Processing Facility (DWPF) at the Savannah River Site began processing of its third sludge batch in March 2004. To avoid a feed outage in the facility, the next sludge batch will have to be prepared and ready for transfer to the DWPF by the end of 2006. The next sludge batch, Sludge Batch 4 (SB4), will consist of a significant volume of HM-type sludge. HM-type sludge is very high in aluminum compared to the mostly Purex-type sludges that have been processed to date. The Savannah River National Laboratory (SRNL) has been working with Liquid Waste Operations to define the sludge preparation plans and to perform testing to support qualification and processing of SB4. Significant challenges have arisen during SB4 preparation and testing to include poor sludge settling behavior and lower than desired projected melt rates. An overview of the testing activities is provided.