Download or read book Development of the Plutonium Oxide Vitrification System written by and published by . This book was released on 1998 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Repository disposal of plutonium in a suitable, immobilized form is being considered as one option for the disposition of surplus weapons-usable plutonium. Accelerated development efforts were completed in 1997 on two potential immobilization forms to facilitate downselection to one form for continued development. The two forms studied were a crystalline ceramic based on Synroc technology and a lanthanide borosilicate (LaBS) glass. As part of the glass development program, melter design activities and component testing were completed to demonstrate the feasibility of using glass as an immobilization medium. A prototypical melter was designed and built in 1997. The melter vessel and drain tube were constructed of a Pt/Rh alloy. Separate induction systems were used to heat the vessel and drain tube. A Pt/Rh stirrer was incorporated into the design to facilitate homogenization of the melt. Integrated powder feeding and off-gas systems completed the overall design. Concurrent with the design efforts, testing was conducted using a plutonium surrogate LaBS composition in an existing (near-scale) melter to demonstrate the feasibility of processing the LaBS glass on a production scale. Additionally, the drain tube configuration was successfully tested using a plutonium surrogate LaBS glass.

Download or read book Vitrification of Simulated Radioactive Rocky Flats Plutonium Containing Ash Residue with a Stir Melter System written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A demonstration trial has been completed in which a simulated Rocky Flats ash consisting of an industrial fly-ash material doped with cerium oxide was vitrified in an alloy tank Stir-Melter[trademark] System. The cerium oxide served as a substitute for plutonium oxide present in the actual Rocky Flats residue stream. The glass developed falls within the SiO[sub 2]+ Al[sub 2]O[sub 3]/[Sigma]Alkali/B[sub 2]O[sub 3] system. The glass batch contained approximately 40 wt% of ash, the ash was modified to contain[approximately] 5 wt% CeO[sub 2] to simulate plutonium chemistry in the glass. The ash simulant was mixed with water and fed to the Stir-Melter as a slurry with a 60 wt% water to 40 wt% solids ratio. Glass melting temperature was maintained at approximately 1,050 C during the melting trials. Melting rates as functions of impeller speed and slurry feed rate were determined. An optimal melting rate was established through a series of evolutionary variations of the control variables' settings. The optimal melting rate condition was used for a continuous six hour steady state run of the vitrification system. Glass mass flow rates of the melter were measured and correlated with the slurry feed mass flow. Melter off-gas was sampled for particulate and volatile species over a period of four hours during the steady state run. Glass composition and durability studies were run on samples collected during the steady state run.

Download or read book ERDA Energy Research Abstracts written by and published by . This book was released on 1977 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Disposal of Weapon Plutonium written by E.R. Merz and published by Springer Science & Business Media. This book was released on 1995-12-31 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: This NATO Advanced Research Workshop on Disposal of Weapons Plutonium is a follow-up event to two preceding workshops, each dealing with a special subject within the overall disarmament issue: "Disposition of Weapon Plutonium", sponsored by the NATO Science Committee. The first workshop of this series was held at the Royal Institute of International Affairs in London on 24-25 January 1994, entitled "Managing the Plutonium Surplus, Applications, and Options". Its over all goal was to clarify the current situation with respect to pluto nium characteristics and availability, the technical options for use or disposal, and their main technical, environmental, and economic constraints. In the immediate term, plutonium recovered from dismantled nuclear warheads will have to be stored securely, and under international safeguards if possible. In the intermediate term, the principal alter natives for disposition of this plutonium are: irradiation in mixed oxide (MOX) fuel assemblies in existing commercial light-water reac tors or in specially adapted light-water reactors capable of operation with full cores of MOX fuel .and irradiation in future fast reactors. Another option is to blend plutonium with high-level waste as it is vitrified for final disposal in a geologic repository. In both cases, the high radioactivity of the resulting products provides "self shielding" and prevents separation of plutonium without already developed and available sophisticated technology. The so-called "spent fuel standard" as an effective protection barrier is - quired in either case.

Download or read book 106 1 Hearings Energy And Water Development Appropriations For 2000 Part 6 March 16 1999 written by and published by . This book was released on 1999 with total page 752 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book OFFGAS GENERATION FROM THE DISPOSITION OF SCRAP PLUTONIUM BY VITRIFICATION SIMULANT TESTS written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Department of Energy Office of Environmental Management is supporting R & D for the conceptual design of the Plutonium Disposition Project at the Savannah River Site in Aiken, SC to reduce the attractiveness of plutonium scrap by fabricating a durable plutonium oxide glass form and immobilizing this form within the high-level waste glass prepared in the Defense Waste Processing Facility. A glass formulation was developed that is capable of incorporating large amounts of actinides as well as accommodating many impurities that may be associated with impure Pu feed streams. The basis for the glass formulation was derived from commercial glasses that had high lanthanide loadings. A development effort led to a Lanthanide BoroSilicate (LaBS) glass that accommodated significant quantities of actinides, tolerated impurities associated with the actinide feed streams and could be processed using established melter technologies. A Cylindrical Induction Melter (CIM) was used for vitrification of the Pu LaBS glass. Induction melting for the immobilization of americium and curium (Am/Cm) in a glass matrix was first demonstrated in 1997. The induction melting system was developed to vitrify a non-radioactive Am/Cm simulant combined with a glass frit. Most of the development of the melter itself was completed as part of that work. This same melter system used for Am/Cm was used for the current work. The CIM system used consisted of a 5 inch (12.7 cm) diameter inductively heated platinum-rhodium (Pt-Rh) containment vessel with a control system and offgas characterization. Scrap plutonium can contain numerous impurities including significant amounts of chlorides, fluorides, sodium, potassium, lead, gallium, chromium, and nickel. Smaller amounts of additional elements can also be present. The amount of chlorides present is unusually high for a melter feed. In commercial applications there is no reason to have chloride at such high concentrations. Because the melter operates at 1400-1475 C, many of the impurities present are extremely volatile. An alternative being considered is to pre-treat the impure PuO2 by water washing to remove the soluble salts, which would significantly reduce the melter emissions. The disadvantage of the washing alternative is the criticality concerns of using water with plutonium. In this paper, the testing that has been conducted at the Savannah River National Laboratory (SRNL) to demonstrate induction melting of impure plutonium simulants will be described. The work described concentrates on quantification of the gaseous and particulate emissions from the induction melter. The Pt-Rh melter vessel is a cylinder with a conical bottom and a tubular drain as shown in Figure 1. A 5-inch (12.7 cm) diameter CIM was used for all of the emissions tests. A 6-inch (15.24 cm) diameter CIM, which is the size of the full-scale melter, has since been constructed for further testing. The 5-inch CIM is heated by three induction coils: one for the 5 inch cylinder, one for the conical section, and one for the 1/4-inch (6.35 mm) drain tube. The 6-inch CIM is similar except the cylinder heater extends lower and also heats the cone. The induction heating system is manufactured by Ameritherm{trademark}. The heating system is controlled by a PC to maintain a specific heat up profile and then maintain a constant energy input that maintains a constant temperature. The CIM is operated in batch mode where the plutonium simulant and the glass-forming frit are first thoroughly mixed in an attrittor mill, then added to the melter. Hafnium oxide (HfO2) is used as a simulant for the radioactive PuO2. The melter is heated until the mixture begins to melt at about 1100 C, then completely melts at about 1400-1450 C. This temperature is maintained for about three hours. While the temperature is maintained at (almost equal to) 1400 C, an air bubbler is normally used to promote mixing of the glass-forming frit and the waste simulant.

Download or read book Advances in Plutonium Chemistry 1967 2000 written by Darleane C. Hoffman and published by Gwasg y Bwthyn. This book was released on 2002 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book ERDA Energy Research Abstracts written by United States. Energy Research and Development Administration. Technical Information Center and published by . This book was released on 1977 with total page 1680 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nuclear Safety written by and published by . This book was released on 1977-03 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Direct Vitrification of Plutonium containing Materials PCM s with the Glass Material Oxidation and Dissolution System GMODS written by and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy and Water Development Appropriations for 1999 Department of Energy fiscal year 1999 budget justifications written by United States. Congress. House. Committee on Appropriations. Subcommittee on Energy and Water Development and published by . This book was released on 1998 with total page 3256 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1976 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy and Water Development Appropriations for 1999 written by United States. Congress. House. Committee on Appropriations. Subcommittee on Energy and Water Development and published by . This book was released on 1998 with total page 1258 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1980 with total page 1280 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Office of Environmental Management Technical Reports written by and published by . This book was released on 1997 with total page 972 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book MacroscoMacroscopic Cracking Determination in LaBS Glasspic Cracking Determination in LaBS Glass written by James Marra and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The DOE/EM plans to conduct the Plutonium Vitrification Project at the Savannah River Site (SRS). An important part of this project is to reduce the attractiveness of the plutonium by fabricating a plutonium glass form and immobilizing the Pu form within the high level waste (HLW) glass prepared in the Defense Waste Processing Facility (DWPF). This requires that a project schedule that is consistent with EM plans for DWPF and cleanup of the SRS be developed. Critical inputs to key decisions in the vitrification project schedule are near-term data that will increase confidence that the lanthanide borosilicate (LaBS) glass product is suitable for disposal in the Yucca Mountain Repository. A workshop was held on April 28, 2005 at Bechtel SAIC Company (BSC) facility in Las Vegas, NV to define the near term data needs. Dissolution rate data and the fate of plutonium oxide and the neutron absorbers during the dissolution process were defined as key data needs. A suite of short-term tests were defined at the workshop to obtain the needed data. The objectives of these short-term tests are to obtain data that can be used to show that the dissolution rate of a LaBS glass is acceptable and to show that the extent of Pu separation from neutron absorbers, as the glass degrades and dissolves, is not likely to lead to criticality concerns. An additional data need was identified regarding the degree of macroscopic cracking and/or voiding that occurs during processing of the Pu glass waste form and subsequent pouring of HLW glass in the DWPF. A final need to evaluate new frit formulations that may increase the durability of the plutonium glass and/or decrease the degree to which neutron absorbers separate from the plutonium during dissolution was identified. This task plan covers the need to evaluate the degree of macroscopic cracking and/or voiding that occurs during processing of the Vitrified Plutonium Waste Form (i.e. the can-in-canister configuration containing the vitrified Pu product). Separate task plans were developed for Pu glass performance testing of the current baseline LaBS glass composition and development of alternative frit formulations. Recent results from Pressurized Unsaturated Flow (PUF) testing showed the potential separation of Pu from Gd during the glass dissolution process [3]. Post-test analysis of the LaBS glass from a 6-year PUF test showed a region where Pu had apparently accumulated in a Pu-bearing disk-like phase that had become separated from neutron absorber (Gd). It should be noted that this testing was conducted on the early LaBS Frit A glass composition that was devoid of HfO{sub 2} as a neutron absorber. PUF testing is currently being initiated using the LaBS Frit B composition that contains HfO{sub 2}. The potential for fissile material and neutron absorber separation is a criticality risk for the repository. The surface area that is available for leaching (i.e. due to the degree of cracking or voiding within the Pu glass cylinder) is a factor in modeling the amount of fissile material and neutron absorber released during the dissolution process. A mathematical expression for surface area is used in the Total Systems Performance Assessment (TSPA) performed by BSC personnel. Specifically, the surface area available for leaching is being used in current external criticality assessments. The planned processing steps for producing a VPWF assembly involves processing Pu feed and LaBS frit to produce a can of Pu LaBS glass, packaging this can into a second can (i.e. bagless transfer) for removal from the glovebox processing environment, placing a series of bagless transfer cans into a DWPF canister, and pouring HLW glass into the DWPF canister to encapsulate bagless transfer cans. The objective of this task is to quantify the degree of cracking and/or voiding that will occur during the processing of the VPWF.

Download or read book Energy Research Abstracts written by and published by . This book was released on 1995 with total page 782 pages. Available in PDF, EPUB and Kindle. Book excerpt: