Demonstration of the defense waste processing facility vitrification process for tank 42 radioactive sludge – glass preparation and characterization

1999 ◽  
Vol 556 ◽  
Author(s):  
Ned E. Bibler ◽  
Terri L. Fellinger ◽  
Kathryn M. Marshall ◽  
Charles L. Crawford ◽  
A. D. Cozzi ◽  
...  

AbstractThe Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) is currently processing and immobilizing the radioactive high level waste sludge at SRS into a durable borosilicate glass for final geological disposal. The DWPF has recently finished processing the first radioactive sludge batch, and is ready for the second batch ofradioactive sludge. The second batch is primarily sludge from Tank 42. Before processing this batch in the DWPF, the DWPF process flowsheet has to be demonstrated with a sample of Tank 42 sludge to ensure that an acceptable melter feed and glass can be made. This demonstration was recently completed in the Shielded Cells Facility at SRS. An earlier paper in these proceedings described the sludge composition and processes necessary for producing an acceptable melter feed [1]. This paper describes the preparation and characterization of the glass from that demonstration. Results substantiate that Tank 42 sludge after mixing with the proper amount of glass forming frit (Frit 200) can be processed to make an acceptable glass.

1999 ◽  
Vol 556 ◽  
Author(s):  
T. L. Fellinger ◽  
N. E. Bibler ◽  
K. M. Marshall ◽  
C. L. Crawford ◽  
M. S. Hay

AbstractThe Defense Waste Processing Facility (DWPF), at the Savannah River Site (SRS), is processing and immobilizing the radioactive high level waste sludge at SRS into a durable borosilicate glass for final geological disposal. The DWPF is currently processing the second, million gallon batch of radioactive sludge. This second batch is primarily from Tank 42. Each time a new batch of radioactive sludge is to be processed by the DWPF, the process flowsheet is to be tested and demonstrated to ensure an acceptable melter feed and glass can be made. This demonstration was completed in the Shielded Cells Facility in the Savannah River Technology Center at SRS.This paper presents the processing and offgas data, and compositional analyses obtained during the preparation of a melter feed for this demonstration. A second paper in this conference describes the properties of the glass produced from this feed. The demonstration used Tank 42 sludge slurry and the DWPF process control strategy for blending the sludge slurry with Frit 200 to make an acceptable melter feed. To prepare feed for the melter, the flowsheet requires that the radioactive sludge slurry be treated with nitric and formic acid to adjust rheology and remove mercury. During this step, hydrogen is formed from the decomposition of the formic acid. The acidified sludge slurry is then mixed with the prescribed amount of glass forming frit and evaporated to the proper weight percent solids to prepare feed to the melter. During this step hydrogen is also formed. Results indicate that the H2 generation rate is below the DWPF safety limits and an acceptable melter feed was produced.


2010 ◽  
Vol 1265 ◽  
Author(s):  
Sergey Stefanovsky ◽  
Alexander Ptashkin ◽  
Oleg Knyazev ◽  
Olga Stefanovsky ◽  
James C Marra

AbstractSavannah River Site Defense Waste Processing Facility (DWPF) Sludge Batch 4 (SB4) high level waste (HLW) simulant at 55 wt % waste loading was produced in the demountable cold crucible and cooled to room temperature in the cold crucible. Appreciable losses of Cs, S and Cl took place during the melting. A second glass sample was subjected to canister centerline cooling (CCC) regime in an alumina crucible in a resistive furnace. X-ray diffraction (XRD) study showed that the glass blocks were composed of vitreous and spinel structure phases. No separate U-bearing phases were found.


Author(s):  
William R. Wilmarth ◽  
Nicholas P. Machara ◽  
Reid A. Peterson ◽  
Sheryl R. Bush

Within the U.S. Department of Energy’s (DOE) Office of Technology Innovation and Development, the Office of Waste Processing manages a research and development program related to the treatment and disposition of radioactive waste. At the Savannah River (South Carolina) and Hanford (Washington) Sites, approximately 90 million gallons of waste are distributed among 226 storage tanks (grouped or collocated in “tank farms”). This waste may be considered to contain mixed and stratified high activity and low activity constituent waste liquids, salts and sludges that are collectively managed as high level waste (HLW). A large majority of these wastes and associated facilities are unique to the DOE, meaning many of the programs to treat these materials are “first-of-a-kind” and unprecedented in scope and complexity. As a result, the technologies required to disposition these wastes must be developed from basic principles, or require significant reengineering to adapt to DOE’s specific applications. Of particular interest recently, the development of In-tank or At-Tank separation processes have the potential to treat waste with high returns on financial investment. The primary objective associated with In-Tank or At-Tank separation processes is to accelerate waste processing. Insertion of the technologies will (1) maximize available tank space to efficiently support permanent waste disposition including vitrification; (2) treat problematic waste prior to transfer to the primary processing facilities at either site (i.e., Hanford’s Waste Treatment and Immobilization Plant (WTP) or Savannah River’s Salt Waste Processing Facility (SWPF)); and (3) create a parallel treatment process to shorten the overall treatment duration. This paper will review the status of several of the R&D projects being developed by the U.S. DOE including insertion of the ion exchange (IX) technologies, such as Small Column Ion Exchange (SCIX) at Savannah River. This has the potential to align the salt and sludge processing life cycle, thereby reducing the Defense Waste Processing Facility (DWPF) mission by 7 years. Additionally at the Hanford site, problematic waste streams, such as high boehmite and phosphate wastes, could be treated prior to receipt by WTP and thus dramatically improve the capacity of the facility to process HLW. Treatment of boehmite by continuous sludge leaching (CSL) before receipt by WTP will dramatically reduce the process cycle time for the WTP pretreatment facility, wile treatment of posphate will significantly reduce the number of HLW borosilicate glass canisters produced at the WTP. These and other promising technologies will be discussed.


2001 ◽  
Vol 7 (S2) ◽  
pp. 498-499
Author(s):  
J. S. Young ◽  
Y. Su ◽  
L. Li ◽  
M. L. Balmer

Millions of gallons of high-level radioactive waste are contained in underground tanks at U. S. Department of Energy sites such as Hanford and Savannah River. Most of the radioactivity is due to 137Cs and 90Sr, which must be extracted in order to concentrate the waste. An ion exchanger, crystalline silicotitanate IONSIV® IE911, is being considered for separation of Cs at the Savannah River Site (SRS). While the performance of this ion exchanger has been well characterized under normal operating conditions, Cs removal at slightly elevated temperatures, such as those that may occur in a process upset, is not clear. Our recent study indicates that during exposure to SRS simulant at 55°C and 80°C, an aluminosilicate coating formed on the exchanger surface. There was concern that the coating would affect its ion exchange properties. A LEO 982 field emission scanning electron microscope (FESEM) and an Oxford ISIS energy dispersive x-ray spectrometer (EDS) were used to characterize the coating.


Author(s):  
Vladimir Lebedev ◽  
Sergey Stefanovsky ◽  
Alexander Kobelev ◽  
Fyodor Lifanov ◽  
Sergey Dmitriev

Results of feasibility tests of application of Cold Crucible Inductive Melting (CCIM) technology to high level waste (HLW) treatment on examples of Savannah River Site, USA, and PA “Mayak”, Russia, HLW, carried out at SIA Radon, and results of design of new perspective bench-scale HLW vitrification facility are presented in this report. Full-scale low level waste (LLW) vitrification plant is under operation at Radon since 2003. Successful Radon experience aroused an interest to this technology from US DOE. Since 2001 Radon performed tests on vitrification of surrogates of various types of HLW stored at US DOE Sites. Process variables were determined and vitrified wastes were characterized in details. Since 2007 Radon was a subcontractor in the project on design and construction of a new CCIM based vitrification facility at PA “Mayak”. From preliminary tests on Mayak HLW surrogates the main technological features of CCIM process were determined and principles of the process control were formulated. Radon performed the design of the cold crucible and automated control system. On the base of analysis of previously and newly obtained data the main requirements to designing of cold crucible melters and auxiliary equipment, intended for actual HLW treatment, were worked out.


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