This report presents the inorganic, organic and radioisotopic analytical results for a composite sample obtained from tank 241-AP-101 (AR 101). This work was conducted in response to a request by BNFL? The results of the analyses are used to assess the waste composition relative to the contract limits defined in Specification 7 for envelope A. Hanford waste tank 241-AP-101 was sampled on February 8,2000 from Riser 002 at depths of 10, 100, 190,290, and 400 inches from the tank bottom, collecting nominally 130 mL per sample! These samples were received under chain-of-custody by the Radiochemical Processing Laboratory Shielded Analytical Laboratory. All samples were clear yellow with no visible settled or suspended solids. The AP-1 01 grab samples were mixed to form one large composite sample according to Test Plan BNFL-TP-29953-083. Sub-samples from this homogenized AP-101 composite sample were then delivered to various laboratories for specific analyses as defined in the analytical service request (ASR) 5778. The sample was given an internal tracking number of 00-1701. All analyses were run in triplicate. The PNNL standards based management system (SBMS) quality assurance plan was used in support of all analytical operations and is in compliance with HASQARD. The inorganic, radioisotopic, and organic analytes of interest, recommended methods, detection limits, and quality assurance parameters were defined by BNFL. The quality requirements were included in ASR 5778. Analyte determinations were performed according to project-approved procedures. This report presents the physical observations from AP-101 and individual density measurements from the various tank depths sampled. Precipitate production was evaluated at 10"C for seven days on a composite subsample. Also presented are the inorganic, radioisotopic, and organic analytical results for the triplicate AP-101 composite samples. Analyte results are compared to Specification 7 Envelope A limits, where applicable. Data limitations are also described. Quality control, detection limits, and other quality control indicators are discussed relevant to the reporting method. Revision 1 includes addition of PCB results as well as minor editorial corrections. 1.1
This report describes the Hanford Tank S-110 sludge caustic leaching test conducted in FY 2001 at the Pacific Northwest National Laboratory. The data presented here can be used to develop the baseline and alternative flowsheets for pretreating Hanford tank sludge. The U.S. Department of Energy funded the work through the Efficient Separations and Processing Crosscutting Program (ESP; EM-50). The S-110 sludge sample was first subjected to washing with dilute sodium hydroxide solution at ambient temperature. Following the dilute hydroxide washing, several aliquots of the washed solids were taken for leaching tests. The washed solids were subjected to leaching with 1, 3, or 5 M NaOH at 60, 80, or 100°C for up to 168 h. The leachates were sampled at 4, 8, 24, 72, and 168 h. The leached solids were dried to constant mass at 105°C and then analyzed. The work presented here indicates caustic leaching to be a very effective method of pretreating Hanford Tank S-110 sludge. Because of the predominance of boehmite in the water-insoluble S-110 solids, high caustic and temperature are required to sufficiently remove Al. It would also be necessary to leach for several days to realize the full benefits of caustic leaching. As expected, Al removal improves with increasing temperature, NaOH concentration, and leaching time. The Cr behavior parallels that of Al. At a maximum of 0.5 wt% Cr 2 O 3 in the high-level waste form, the mass of immobilized high-level waste (IHLW) would be constrained by the Cr content of the leached S-110 solids. Nevertheless, an 80 to 90% reduction in IHLW mass from the S-110 solids should be readily achievable. The results of this work underscore the need to continue process optimization studies. If subjected to the baseline leaching approach (3 M NaOH, 80 to 90°C, for 8 h), only about 25% of the Al would be leached from the dilute hydroxide-washed S-110 solids. Clearly, this would not be sufficient to adequately reduce the IHLW mass.
SummaryThe U.S. Department of Energy (DOE) Office of River Protection (ORP) has acquired Hanford tank waste treatment services at a demonstration scale. The River Protection Project Waste Treatment Plant (RPP-WTP) team is responsible for producing an immobilized (vitrified) high-level waste (IHLW) waste form. Pacific Northwest National Laboratory, hereafter referred to as PNNL, has been contracted to produce and test a vitrified IHLW waste form from two Envelope D high-level waste (HLW) samples previously supplied to the RPP-WTP project by DOE.The primary objective for vitrifying the HLW samples is to generate glass products for subsequent product testing. The scope of the Vitrification and Product Testing has been divided into eight work elements: 1) Glass Fabrication, 2) Chemical Composition, 3) Radiochemical Composition, 4) Crystalline and Non-crystalline Phase Determination, 5) Release Rate (PCT), 6) Toxicity Characteristic Leaching Procedure (TCLP), 7) Total volatile organic and semi-volatile organic analyses (VOA and SVOA), and 8) WAPS, regulatory, and de-listing testing. The work presented in this report is from only the following 5 work elements: 1) Glass Fabrication, 2) Chemical Composition, 3) Radiochemical Composition, 4) Crystalline and Non-crystalline Phase Determination, and 5) Release Rate (PCT). These work elements will help demonstrate the RPP-WTP projects ability to satisfy the product requirements concerning, chemical and radionuclide reporting, waste loading, identification and quantification of crystalline and non-crystalline phases, and waste form leachability. Results from work elements 6 through 8, i.e. VOA, SVOA, dioxins, furans, PCBs, and total cyanide and sulfide analyses are reported in a separate document (Goheen et al., WTP-RPT-010).Two pretreated tank sludge samples, high-level wastes (241-C-104 and 241-AZ-102) hereafter referred to as C-104 and AZ-102 along with a HLW process simulant (know as the HLW Process Blank) were prepared as melter feeds for vitrification. Due to scheduling constraints and small initial sample size of the pretreated tank 241-AZ-102 sludge, this sample was divided into two samples that were vitrified separately (i.e. AZ-102, Melt 1 and AZ-102, Melt 2). The analyzed compositions of the pretreated C-104 and AZ-102 sludge wastes were used by Catholic University of America's (CUA) Vitreous State Laboratory (VSL) to determine the target glass composition.The two tank sludge samples, were processed through pretreatment chemical washing and leaching processes, and the pretreated sludges were converted to high-level waste (HLW) glass after flowsheet quantities of secondary wastes, i.e. Sr/TRU precipitate and Cs and Tc ion exchange eluants, generated from LAW supernatant pretreatment unit operations were added. Both sludge samples were processed through the following unit operations to simulate the RPP-WTP project flowsheet: 1) initial characterization; 2) washing; 3) leaching; and 4) filtration in a crossflow filtration system (Brooks et al., 2000a) (Brooks et al.,...
This report describes the caustic leaching test conducted on Hanford Tank T-110 sludge during FY 2002 at the Pacific Northwest National Laboratory. The data presented here can be used to develop the baseline and alternative flowsheets for pretreating Hanford tank sludge. The U.S. Department of Energy funded the work through the Efficient Separations and Processing Crosscutting Program (ESP; EM-50). The T-110 sludge sample was first subjected to washing with dilute sodium hydroxide solution at ambient temperature. Following the dilute hydroxide washing, several aliquots of the washed solids were taken for leaching tests. The washed solids were subjected to leaching with 1, 3, or 5 M NaOH at 60, 80, or 100°C for up to 168 h. The leachates were sampled at 4, 8, 24, 72, and 168 h. The leached solids were dried to constant mass at 105°C and then analyzed. Bismuth, Fe, Na, P, and Si are the dominant elements present in the T-110 sludge. As expected, Na is largely (> 90%) removed by dilute hydroxide washing. However, dilute hydroxide washing is ineffectual at removing Bi, Fe, or Si. For this particular sludge, the behavior of P is of major concern due to the relatively low tolerance for this element in the high-level waste (HLW) immobilization process and the high concentration of P in the waste. Only 33% of the P was removed by dilute hydroxide washing, resulting in washed solids that were 8.8 wt% P. This is presumably because the P is present as bismuth phosphate in the T-110 solids. More rigorous pretreatment (e.g., caustic leaching) will be required to remove enough P so that it is not a limiting component in the sludge solids. The minor sludge component, Cr, can also adversely affect the HLW immobilization process. The Cr in the T-110 sludge was largely insoluble in 0.01 M NaOH, with only 3% being removed by dilute hydroxide washing. The solution obtained by washing the T-110 solids with dilute hydroxide could likely be immobilized as a Class A low-level waste (LLW), even without removing 137 Cs. The work presented here indicates caustic leaching to be a very effective method for pretreating Hanford Tank T-110 sludge, primarily because this method essentially quantitatively removes P from the water-washed T-110 solids. Assuming a P 2 O 5 limit of 3 wt% in the immobilized high-level waste (IHLW) glass, it is estimated that caustic leaching will result in an ~80% reduction in the IHLW mass. Unlike high-Al tanks (see for example, Lumetta et al. 2001), relatively mild leaching conditions (1 M NaOH at 60°C) should sufficiently remove P from the T-110 solids. However, more rigorous leaching conditions (or oxidative leaching) may be needed to avoid encountering the Cr limit in the glass formulation. The leaching of P from the sludge solids is rapid and largely independent of temperature and NaOH concentration. On the other hand, the leaching of Cr is much slower and is highly dependent on temperature and NaOH concentration. Some of the caustic-leaching solutions contained significant concentrations of transuranic (TRU) el...
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