Evaluation of special safety issues associated with handling the Three Mile Island Unit 2 core debris

Henrie, J.O.; Appel, J.N.

doi:10.2172/5745202

Cited by 8 publications

(4 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The gamma-ray dose rate Balanced with total anion concentration F − , BO 3 2− and others in seawater Ignored during shutdown operation was evaluated by multiplying average decay heat of fuels by 0.1. This method was used to evaluate the radiolytic hydrogen production rate from the Three Mile Island core debris [18]. Concentrations of radiolytic species were calculated for 10 5 s because the high temperature (>100 • C) period of reactor water during the shutdown was 1 day.…”

Section: Calculation Conditionsmentioning

confidence: 99%

Effects of seawater components on radiolysis of water at elevated temperature and subsequent integrity of fuel materials

Wada

Tachibana

Watanabe

et al. 2015

Journal of Nuclear Science and Technology

View full text Add to dashboard Cite

Effects of seawater components on radiolysis of water at elevated temperature have been studied with a radiolysis model and a corrosion test under gamma-ray irradiation conditions to evaluate the subsequent influence on integrity of fuel materials used in an advanced boiling water reactor. In 2011, seawater flowed into the nuclear power plant system of the Hamaoka Nuclear Power Station Reactor No. 5 during the plant shutdown operation. The reactor water temperature was 250 • C and its maximum Cl − concentration was ca. 450 ppm when seawater was mixed with reactor water. The radiolysis model predicted that the main radiolytic species were hydrogen, oxygen and hydrogen peroxide. Concentrations of radiolytic products originating from Cl − and other seawater components were found to be rather low. The dominant product among them was ClO 3 − and its concentration was found to be below 0.01 ppm for a 10 5 s irradiation period. No significant corrosion of zircaloy-2 and 316L stainless steel was found in the corrosion test. These results led to the conclusion that the harmful influence of radiolytic products originating from seawater components on integrity of fuel materials must be smaller than that of Cl − which is the main ionic species in seawater.

show abstract

Section: Calculation Conditionsmentioning

confidence: 99%

Effects of seawater components on radiolysis of water at elevated temperature and subsequent integrity of fuel materials

Wada

Tachibana

Watanabe

et al. 2015

Journal of Nuclear Science and Technology

View full text Add to dashboard Cite

show abstract

“…2) During the decommissioning of Three Mile Island Unit 2 (TMI-2), radioactive waste and water were processed and stored in tanks with Pd-Pt-Al 2 O 3 catalyst to promote hydrogen and oxygen recombination. 3) On the other hand, the Fukushima Daiichi Nuclear Power Plant must operate multiple radionuclide removal and other water treatment systems, which will generate a lot more water-carrying radioactive waste than the one of TMI-2. 2) Therefore, it is very important to develop a costfriendly catalyst and a support composed of metal or inorganic materials and have long-term chemical stability.…”

Section: Introductionmentioning

confidence: 99%

Effect of dehydration time and air tightness on pore distribution of potassium and metakaolin-based geopolymer

Yang¹,

Le²,

Kudou³

et al. 2022

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

As a catalyst support in the nuclear waste containers in the Fukushima Daiichi Nuclear Power Station, geopolymer is required to show high strength, high porosity and durability. The aim of this study is to evaluate the mechanical properties and pore size distribution of hardened samples based on two test variables, which include early-age dehydration time and air tightness. The early-age dehydration time ranges from 1–4 d, and air tightness is implemented using the two methods of total sealing and air contact. However, the average pore size was around 2.0 × 102 μm, the Vickers hardness was around 90 MPa, and the relative weight change on the 14th day was within 10% for all the samples that were not affected by the curing time and air tightness. It can be inferred that the pores of the sample may have been formed within a day and may not be affected by the curing time.

show abstract

“…Thus, the radioactive slurry should be stored in containers with catalysts that promote hydrogen–oxygen recombination 2 . In a similar accident at Three Mile Island Nuclear Power Station, a Pt‐Pd‐Al 2 O 3 catalyst was used 3 . Due to the large amount of nuclear waste in Fukushima, this solution is not feasible due to the high cost and large volume.…”

Section: Introductionmentioning

confidence: 99%

Pore‐forming process in dehydration of metakaolin‐based geopolymer

Yang

Kudo

et al. 2021

Int J Ceramic Engine & Sci

View full text Add to dashboard Cite

The geopolymer catalyst supports utilized in the nuclear waste containers for the Fukushima Daiichi Nuclear Power Station, will be required to have high porosity, and durability. This work presents the synthesis of a potassium and metakaolin based geopolymer and its performance upon dehydration. During water content measurements of the samples, it was seen that in the demolded samples, the water content quickly decreased to less than 30% within 7 days, while the samples, that had the cap removed from the container retained more than 50% of the water Accepted ArticleThis article is protected by copyright. All rights reserved after 28 days. The pore size distribution of the samples that were post-cured at different temperatures up to 28 days did not vary greatly with respect to the average pore size. We can infer that structurally stable pores were formed in the first 4 days and were not affected by the post-curing rate, which may be related to rheological properties and the drainage path of water or hydrogen gas during post-curing.

show abstract

Evaluation of special safety issues associated with handling the Three Mile Island Unit 2 core debris

Cited by 8 publications

References 3 publications

Effects of seawater components on radiolysis of water at elevated temperature and subsequent integrity of fuel materials

Effects of seawater components on radiolysis of water at elevated temperature and subsequent integrity of fuel materials

Effect of dehydration time and air tightness on pore distribution of potassium and metakaolin-based geopolymer

Pore‐forming process in dehydration of metakaolin‐based geopolymer

Contact Info

Product

Resources

About