Technical summary:  Nuclear Waste Vitrification Project

Wheelwright, E.J.; Bjorklund, W.J.; Browne, Larry M.; Bryan, G.H.; Holton, L.K.; Irish, E.R.; Siemens, D.H.

doi:10.2172/6086723

Cited by 7 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The project was eventually placed in a standby mode by the U.S. Department of Energy in 1980. The NWVP is discussed in reports published by PNNL (Wheelwright et al 1979(Wheelwright et al , 1996.…”

Section: Historymentioning

confidence: 99%

Radiochemical Processing Laboratory High-Level Vault Characterization Report

Steen¹,

Baker²,

Valdez³

et al. 2007

View full text Add to dashboard Cite

SummaryThe High Level Vaults (HLV) consists of three underground concrete vaults containing seven tanks. The tanks were used to support a variety of radiochemical processes conducted in the High Level Radiochemistry Facility (HLRF) hot cells. The HLRF is located adjacent to the east wall of the 325 Building, which also is known as the Radiochemical Processing Facility (RPL).Initial radiological and chemical conditions and video documentation of the interior of the HLV were obtained by disassembling the HLV high efficiency particulate air (HEPA) filter housings and inserting remote monitoring equipment through the openings. The radiological dose rates obtained near the filter housing inlets ranged from less than the minimum detectable amount (MDA) to 150 mRem/hr. The results indicated that the HLV access cover block could be safely removed.The weather barrier covering the HLV cover blocks was removed and discarded. To extend the working surface, a two-foot strip of concrete was installed around the perimeter of the HLV. Reinforced plastic sheeting was secured over the cover blocks to prevent rainwater incursion into the HLV.A work structure (containment) was erected over the HLV so the vault could be accessed while maintaining a radiologically controlled environment over the work area. The containment was installed so that both the key cover block and the inlet HEPA filter were enclosed. Positioning the containment in this manner was instrumental in maintaining proper air flow when removing and replacing the vault cover blocks. The vaults were exhausted via the RPL Radioactive Exhaust Ventilation System, and the existing system design and configuration was adequate to exhaust the containment and the vault being accessed.A portable gantry hoist erected inside the containment was used to remove the HLV key access cover block. A remotely operated vehicle (ROV), hand-held reach tools, and associated sampling equipment were inserted into each HLV via an open access cover block. The ROV was equipped with a robotic arm that was used to transport and maneuver radiological survey and characterization sampling equipment through the interior of the HLV. Hand-held extension tools manipulated through the HLV access openings were also used to obtain radiological dose rates and characterization samples.Characterization samples consisted of several removable contamination smears from the surfaces of the HLV walls and tanks, liquid obtained from the HLV sump trenches, and samples of debris (soil) from the HLV floor. Samples were submitted to the analytical laboratory and analyzed for total alpha (TA), total beta (TB), alpha energy analysis (AEA), gamma energy analysis (GEA), and beryllium by inductively coupled plasma (ICP) spectrophotometry. The analytical results indicated that the radiological characteristics were consistent within each HLV, and no beryllium was detected in the characterization samples.The dose data obtained during characterization activities indicate the maximum dose rates on the tanks are approximately 160 m...

show abstract

Section: Historymentioning

confidence: 99%

Radiochemical Processing Laboratory High-Level Vault Characterization Report

Steen¹,

Baker²,

Valdez³

et al. 2007

View full text Add to dashboard Cite

show abstract

“…ATM-5 is fully loaded with actual waste from the reprocessing of commercial nuclear fuel. This waste was generated during the Nuclear Waste Vitrification Project (NWVP) at PNL (Wheelwright et al 1979).…”

Section: Fully Radioactivementioning

confidence: 99%

Approved reference and testing materials for use in Nuclear Waste Management Research and Development Programs

Mellinger¹,

Daniel²

1984

View full text Add to dashboard Cite

“…This full-scale unit has solidified ~390,000 L of simulated wastes during 1830 h of processing time • To complete spray calciner/melter process development for plant application, a process verification program (Nuclear Waste Vitrification Program) was implemented. The program included the processing of actual high-level waste from spent nuclear power-reactor fuels into borosilicate glass and filling two canisters with this glass in 1979 (Wheelwright et al 1979;Bonner et al 1980;Hanson and Bjorklund 1980). The pilot-scale unit (about a 15-L/h feed capacity) produced two canisters [20 em (8 in.…”

Section: Introductionmentioning

confidence: 99%

Design and performance of a full-scale spray calciner for nonradioactive high-level-waste-vitrification studies

Miller¹

1981

View full text Add to dashboard Cite

Since 1977, the Pacific Northwest Laboratory has tested a large-scale spray calciner for the solidification of simulated high-level neutralized and acid radioactive wastes. This is a report of valuable operating experience gained during 1830 h of processing time in which ~390,000 L of simulated wastes were solidified.Experience from spray calciner operations has demonstrated that atomizing-nozzle flow conditions that produce 100-~ median-volume-diameter or smaller droplets are required for large-scale spray calciners. Both internal-and external-mix nozzles have been tested. Due to its lower airflow requirements and the fewer large droplets produced, the internal-mix nozzle has been chosen for primary development in the spray calciner program at PNL. Atomizing nozzle air caps made of reaction-bonded or hot-pressed silicon nitride should provide satisfactory wear resistance and thermal shock resistance for long-term spray calciner operation.While several alternative feed system components exist, spray calciner feed system experience at PNL has been primarily with a centrifugal pump, control valve, and magnetic flowmeter. This system has performed satisfactorily, and problems have been limited to the following:• occasional plugging in the magnetic flowmeter by large foreign particles. (This problem was solved by reducing the size of the strainer-screen mesh to remove particles larger than the flowmeter orifice and by installing a larger flowmeter that had a 0.64-cm orifice instead of a 0.40-cm opening.)• erosion of the pump impeller housing, pipe elbows and ball valve in the feed tank's 304L stainless steel recirculation line resulting from feeds containing a high percentage of solids. (Solutions to this problem include use of a more erosion-resistant piping material, long-radius elbows or piping bends, ball valves with port diameters at least as large as the pipe's inside diameter, and lower fluid velocities.)• minor settling of solids around the outside edges on the bottom of the flat-bottomed tank. (Use of tank with a conical or dished bottom would be a solution to this problem.)The spray calciner has been operated at chamber wall temperatures from 400° to 900°C, depending on the type of waste feed and the feedrate. Calcine sintering, corrosion, and thermal stresses limit the maximum temperature. Rates up to 400 L/h have been demonstrated.Total furnace power requirements (not including heat losses) can be predicted by assuming that the waste feed is water and calculating the sensible and latent heat required to raise the inlet feed and atomizing air to the desired offgas outlet temperature. Furnace power consumption is not axially uniform. Data from actual calciner operation indicate that 60% of the power input is supplied by the lower half of the furnace. This is likely due to convective flow patterns inside the spray chamber.

show abstract

Technical summary: Nuclear Waste Vitrification Project

Cited by 7 publications

References 0 publications

Radiochemical Processing Laboratory High-Level Vault Characterization Report

Radiochemical Processing Laboratory High-Level Vault Characterization Report

Approved reference and testing materials for use in Nuclear Waste Management Research and Development Programs

Design and performance of a full-scale spray calciner for nonradioactive high-level-waste-vitrification studies

Contact Info

Product

Resources

About